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Kouz K, Thiele R, Michard F, Saugel B. Haemodynamic monitoring during noncardiac surgery: past, present, and future. J Clin Monit Comput 2024; 38:565-580. [PMID: 38687416 PMCID: PMC11164815 DOI: 10.1007/s10877-024-01161-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 04/02/2024] [Indexed: 05/02/2024]
Abstract
During surgery, various haemodynamic variables are monitored and optimised to maintain organ perfusion pressure and oxygen delivery - and to eventually improve outcomes. Important haemodynamic variables that provide an understanding of most pathophysiologic haemodynamic conditions during surgery include heart rate, arterial pressure, central venous pressure, pulse pressure variation/stroke volume variation, stroke volume, and cardiac output. A basic physiologic and pathophysiologic understanding of these haemodynamic variables and the corresponding monitoring methods is essential. We therefore revisit the pathophysiologic rationale for intraoperative monitoring of haemodynamic variables, describe the history, current use, and future technological developments of monitoring methods, and finally briefly summarise the evidence that haemodynamic management can improve patient-centred outcomes.
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Affiliation(s)
- Karim Kouz
- Department of Anesthesiology, Center of Anesthesiology and Intensive Care Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, Hamburg, 20246, Germany
- Outcomes Research Consortium, Cleveland, OH, USA
| | - Robert Thiele
- Department of Anesthesiology, University of Virginia, Charlottesville, VA, USA
| | | | - Bernd Saugel
- Department of Anesthesiology, Center of Anesthesiology and Intensive Care Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, Hamburg, 20246, Germany.
- Outcomes Research Consortium, Cleveland, OH, USA.
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Kandil S, Sedra A. Hemodynamic monitoring in liver transplantation 'the hemodynamic system'. Curr Opin Organ Transplant 2024; 29:72-81. [PMID: 38032246 DOI: 10.1097/mot.0000000000001125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
PURPOSE OF REVIEW The purpose of this article is to provide a comprehensive review of hemodynamic monitoring in liver transplantation. RECENT FINDINGS Radial arterial blood pressure monitoring underestimates the aortic root arterial blood pressure and causes excessive vasopressor and worse outcomes. Brachial and femoral artery monitoring is well tolerated and should be considered in critically ill patients expected to be on high dose pressors. The pulmonary artery catheter is the gold standard of hemodynamic monitoring and is still widely used in liver transplantation; however, it is a highly invasive monitor with potential for serious complications and most of its data can be obtained by other less invasive monitors. Rescue transesophageal echocardiography relies on few simple views and should be available as a standby to manage sudden hemodynamic instability. Risk of esophageal bleeding from transesophageal echocardiography in liver transplantation is the same as in other patient populations. The arterial pulse waveform analysis based cardiac output devices are minimally invasive and have the advantage of real-time beat to beat monitoring of cardiac output. No hemodynamic monitor can improve clinical outcomes unless integrated into a goal-directed hemodynamic therapy. The hemodynamic monitoring technique should be tailored to the patient's medical status, surgical technique, and the anesthesiologist's level of expertise. SUMMARY The current article provides a review of the current hemodynamic monitoring systems and their integration in goal-directed hemodynamic therapy.
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Affiliation(s)
- Sherif Kandil
- Department of Anesthesiology, Keck Medical School of USC, Los Angeles, California, USA
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Horejsek J, Balík M, Kunstýř J, Michálek P, Kopecký P, Brožek T, Bartošová T, Fink A, Waldauf P, Porizka M. Internal jugular vein collapsibility does not predict fluid responsiveness in spontaneously breathing patients after cardiac surgery. J Clin Monit Comput 2023; 37:1563-1571. [PMID: 37572237 DOI: 10.1007/s10877-023-01066-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 07/30/2023] [Indexed: 08/14/2023]
Abstract
PURPOSE The objective of our study was to evaluate the diagnostic accuracy of internal jugular vein (IJV) collapsibility as a predictor of fluid responsiveness in spontaneously breathing patients after cardiac surgery. METHODS In this prospective observational study, spontaneously breathing patients were enrolled on the first postoperative day after coronary artery bypass grafting. Hemodynamic data coupled with simultaneous ultrasound assessment of the IJV were collected at baseline and after passive leg raising test (PLR). Continuous cardiac index (CI), stroke volume (SV), and stroke volume variation (SVV) were assessed with FloTracTM/EV1000™. Fluid responsiveness was defined as an increase in CI ≥ 10% after PLR. We compared the differences in measured variables between fluid responders and non-responders and tested the ability of ultrasonographic IJV indices to predict fluid responsiveness. RESULTS Fifty-four patients were included in the study. Seventeen (31.5%) were fluid responders. The responders demonstrated significantly lower inspiratory and expiratory diameters of the IJV at baseline, but IJV collapsibility was comparable (P = 0.7). Using the cut-off point of 20%, IJV collapsibility predicted fluid responsiveness with a sensitivity of 76.5% and specificity of 38.9%, ROC AUC 0.55. CONCLUSION In spontaneously breathing patients after surgical coronary revascularisation, collapsibility of the internal jugular vein did not predict fluid responsiveness.
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Affiliation(s)
- Jan Horejsek
- Department of Anaesthesiology and Intensive Care Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, 12808, Czech Republic
| | - Martin Balík
- Department of Anaesthesiology and Intensive Care Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, 12808, Czech Republic
| | - Jan Kunstýř
- Department of Anaesthesiology and Intensive Care Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, 12808, Czech Republic
| | - Pavel Michálek
- Department of Anaesthesiology and Intensive Care Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, 12808, Czech Republic
- Department of Anaesthesia, Antrim Area Hospital, Antrim, BT41 2RL, UK
| | - Petr Kopecký
- Department of Anaesthesiology and Intensive Care Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, 12808, Czech Republic
| | - Tomáš Brožek
- Department of Anaesthesiology and Intensive Care Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, 12808, Czech Republic
| | - Tereza Bartošová
- Department of Anaesthesiology and Intensive Care Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, 12808, Czech Republic
| | - Adam Fink
- First Faculty of Medicine, Charles University in Prague, Prague, 12808, Czechia
| | - Petr Waldauf
- Department of Anaesthesiology and Resuscitation, Third Faculty of Medicine, Charles University in Prague and University Hospital Královské Vinohrady in Prague, Prague, 10034, Czechia
| | - Michal Porizka
- Department of Anaesthesiology and Intensive Care Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, 12808, Czech Republic.
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Parulekar P, Powys-Lybbe J, Bassett P, Roques S, Snazelle M, Millen G, Harris T. Comparison of cardiac index measurements in intensive care patients using continuous wave vs. pulsed wave echo-Doppler compared to pulse contour cardiac output. Intensive Care Med Exp 2023; 11:23. [PMID: 37106217 PMCID: PMC10140233 DOI: 10.1186/s40635-023-00499-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 02/10/2023] [Indexed: 04/29/2023] Open
Abstract
PURPOSE Cardiac index (CI) assessments are commonly used in critical care to define shock aetiology and guide resuscitation. Echocardiographic assessment is non-invasive and has high levels of agreement with thermodilution assessment of CI. CI assessment is derived from the velocity time integral (VTI) assessed using pulsed wave (PW) doppler at the level of the left ventricular outflow tract divided by body mass index. Continuous wave (CW) doppler through the aortic valve offers an alternative means to assess VTI and may offer better assessment at high velocities. METHODS We performed a single centre, prospective, observational study in a 15-bed intensive care unit in a busy district general hospital. Patients had simultaneous measurements of cardiac index by Pulse Contour Cardiac Output (PiCCO) (thermodilution), transthoracic echocardiographic PW-VTI and CW-VTI. Mean differences were measured with Bland-Altman limits of agreement and percentage error (PE) calculations. RESULTS Data were collected on 52 patients. 71% were supported with noradrenaline with or without additional inotropic or vasopressor agents. Mean CIs were: CW-VTI 2.7 L/min/m2 (range 0.78-5.11, SD 0.92). PW-VTI 2.33 L/min/m2 (range 0.77-5.40, SD 0.90) and PiCCO 2.86 L/min/m2 (range 1.50-5.56, SD 0.93). CW-VTI and PiCCO mean difference was - 0.16 L/min/m2 PE 43.5%. PW-VTI and PiCCO had a mean difference of - 0.54 L/min/m2 PE 38.6%. CW-VTI and PW-VTI had a mean difference of 0.38 L/min/m2 PE 46.0%. CONCLUSIONS CI derived from both CW-VTI and PW-VTI methods underestimate CI compared to PiCCO, with the CW-VTI method having closer values overall to PiCCO. CW-VTI may offer a more accurate assessment of CI. If using Critchley's PE cutoff of 30%, none of the doppler methods may accurately reflect the actual cardiac index.
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Affiliation(s)
- Prashant Parulekar
- Intensive Care and Acute Medicine, East Kent Hospitals University NHS Foundation Trust, William Harvey Hospital, London, UK.
| | | | | | - Seb Roques
- East Kent Hospitals University NHS Foundation Trust, William Harvey, London, UK
| | - Mark Snazelle
- East Kent Hospitals University NHS Foundation Trust, William Harvey, London, UK
| | - Gemma Millen
- East Kent Hospitals University NHS Foundation Trust, William Harvey, London, UK
| | - Tim Harris
- East Kent Hospitals University NHS Foundation Trust, William Harvey, London, UK
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Horejsek J, Balík M, Kunstýř J, Michálek P, Brožek T, Kopecký P, Fink A, Waldauf P, Pořízka M. Prediction of Fluid Responsiveness Using Combined End-Expiratory and End-Inspiratory Occlusion Tests in Cardiac Surgical Patients. J Clin Med 2023; 12:jcm12072569. [PMID: 37048651 PMCID: PMC10094769 DOI: 10.3390/jcm12072569] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/24/2023] [Accepted: 03/28/2023] [Indexed: 03/31/2023] Open
Abstract
End-expiratory occlusion (EEO) and end-inspiratory occlusion (EIO) tests have been successfully used to predict fluid responsiveness in various settings using calibrated pulse contour analysis and echocardiography. The aim of this study was to test if respiratory occlusion tests predicted fluid responsiveness reliably in cardiac surgical patients with protective ventilation. This single-centre, prospective study, included 57 ventilated patients after elective coronary artery bypass grafting who were indicated for fluid expansion. Baseline echocardiographic measurements were obtained and patients with significant cardiac pathology were excluded. Cardiac index (CI), stroke volume and stroke volume variation were recorded using uncalibrated pulse contour analysis at baseline, after performing EEO and EIO tests and after volume expansion (7 mL/kg of succinylated gelatin). Fluid responsiveness was defined as an increase in cardiac index by 15%. Neither EEO, EIO nor their combination predicted fluid responsiveness reliably in our study. After a combined EEO and EIO, a cut-off point for CI change of 16.7% predicted fluid responsiveness with a sensitivity of 61.8%, specificity of 69.6% and ROC AUC of 0.593. In elective cardiac surgical patients with protective ventilation, respiratory occlusion tests failed to predict fluid responsiveness using uncalibrated pulse contour analysis.
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Hon S, Martin-Flores M, Koehler P, Gleed R, Campoy L. Evaluation of transpulmonary ultrasound dilution cardiac output in piglets: accuracy, precision and trending ability with room temperature injectate. Vet Anaesth Analg 2023; 50:163-169. [PMID: 36641330 DOI: 10.1016/j.vaa.2022.11.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Transpulmonary ultrasound dilution (TPUD) is a minimally invasive technique to measure cardiac output (CO) using a 1 mL kg-1 isotonic 37 °C saline injectate indicator. The objective was to evaluate the performance of TPUD using a room temperature saline injectate. STUDY DESIGN Prospective experimental trial. ANIMALS A total of seven anesthetized male Yorkshire piglets. METHODS Piglets aged 1 month and weighing 7.7-9.0 kg were anesthetized with detomidine-ketamine-hydromorphone-isoflurane and a pulmonary artery flow probe (PAFP) placed via a median sternotomy. The thoracic cavity remained open during measurement of CO by PAFP and TPUD. The TPUD indicators of 1 mL kg-1 0.9% saline at 37 °C and 20 °C were compared during infusions of phenylephrine and dobutamine, blood withdrawal and replacement. Bias, limits of agreement (LoAs) and percentage error (PE) between each iteration of PAFP and TPUD were measured with Bland-Altman plots. Trending ability via concordance, angular bias and radial LoA were compared. RESULTS Bland-Altman plots showed negligible bias with varying LoAs. PEs of 22% and 38% were found for 37 °C and 20 °C saline injectates, respectively. In the four-quadrant plots, the concordance rate was 94% and 100% for measurements obtained with 37 °C and 20 °C saline injectates, respectively. Angular bias for both were < ±5 °, with radial LoA < ±7 °. CONCLUSIONS TPUD was accurate when using 1 mL kg-1 of isotonic saline at 37 °C in a range of CO within 0.2-0.8 L minute-1, and it reliably tracked positive and negative changes in CO. Room temperature (20 °C) indicator was less accurate but equally able to track direction of changes in CO. CLINICAL RELEVANCE The use of room temperature injectates allows an easy, readily available clinical application of TPUD CO monitoring while preserving the trending ability of the monitor.
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Affiliation(s)
- Stephanie Hon
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
| | - Manuel Martin-Flores
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Perry Koehler
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Robin Gleed
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Luis Campoy
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
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Komanek T, Rabis M, Omer S, Peters J, Frey UH. Quantification of left ventricular ejection fraction and cardiac output using a novel semi-automated echocardiographic method: a prospective observational study in coronary artery bypass patients. BMC Anesthesiol 2023; 23:65. [PMID: 36855077 PMCID: PMC9972694 DOI: 10.1186/s12871-023-02025-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 02/21/2023] [Indexed: 03/02/2023] Open
Abstract
BACKGROUND Echocardiographic quantification of ejection fraction (EF) by manual endocardial tracing requires training, is time-consuming and potentially user-dependent, whereas determination of cardiac output by pulmonary artery catheterization (PAC) is invasive and carries a risk of complications. Recently, a novel software for semi-automated EF and CO assessment (AutoEF) using transthoracic echocardiography (TTE) has been introduced. We hypothesized that AutoEF would provide EF values different from those obtained by the modified Simpson's method in transoesophageal echocardiography (TOE) and that AutoEF CO measurements would not agree with those obtained via VTILVOT in TOE and by thermodilution using PAC. METHODS In 167 patients undergoing coronary artery bypass graft surgery (CABG), TTE cine loops of apical 4- and 2-chamber views were recorded after anaesthesia induction under steady-state conditions. Subsequently, TOE was performed following a standardized protocol, and CO was determined by thermodilution. EF and CO were assessed by TTE AutoEF as well as TOE, using the modified Simpson's method, and Doppler measurements via velocity time integral in the LV outflow tract (VTILVOT). We determined Pearson's correlation coefficients r and carried out Bland-Altman analyses. The primary endpoints were differences in EF and CO. The secondary endpoints were differences in left ventricular volumes at end diastole (LVEDV) and end systole (LVESV). RESULTS AutoEF and the modified Simpson's method in TOE showed moderate EF correlation (r = 0.38, p < 0.01) with a bias of -12.6% (95% limits of agreement (95%LOA): -36.6 - 11.3%). AutoEF CO correlated poorly both with VTILVOT in TOE (r = 0.19, p < 0.01) and thermodilution (r = 0.28, p < 0.01). The CO bias between AutoEF and VTILVOT was 1.33 l min-1 (95%LOA: -1.72 - 4.38 l min-1) and 1.39 l min-1 (95%LOA -1.34 - 4.12 l min-1) between AutoEF and thermodilution, respectively. AutoEF yielded both significantly lower EF (EFAutoEF: 42.0% (IQR 29.0 - 55.0%) vs. EFTOE Simpson: 55.2% (IQR 40.1 - 70.3%), p < 0.01) and CO values than the reference methods (COAutoEF biplane: 2.30 l min-1 (IQR 1.30 - 3.30 l min-1) vs. COVTI LVOT: 3.64 l min-1 (IQR 2.05 - 5.23 l min-1) and COPAC: 3.90 l min-1 (IQR 2.30 - 5.50 l min-1), p < 0.01)). CONCLUSIONS AutoEF correlated moderately with TOE EF determined by the modified Simpson's method but poorly both with VTILVOT and thermodilution CO. A systematic bias was detected overestimating LV volumes and underestimating both EF and CO compared to the reference methods. TRIAL REGISTRATION German Register for Clinical Trials (DRKS-ID DRKS00010666, date of registration: 08/07/2016).
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Affiliation(s)
- Thomas Komanek
- Klinik für Anästhesiologie, operative Intensivmedizin, Schmerz- und Palliativmedizin, Marien Hospital Herne - Universitätsklinikum der Ruhr-Universität Bochum, Hölkeskampring 40, 44625, Herne, Germany.,Klinik für Anästhesiologie und Intensivmedizin, Universität Duisburg-Essen und Universitätsklinikum Essen, Essen, Germany
| | - Marco Rabis
- Klinik für Anästhesiologie und Intensivmedizin, Universität Duisburg-Essen und Universitätsklinikum Essen, Essen, Germany
| | - Saed Omer
- Klinik für Anästhesiologie, operative Intensivmedizin, Schmerz- und Palliativmedizin, Marien Hospital Herne - Universitätsklinikum der Ruhr-Universität Bochum, Hölkeskampring 40, 44625, Herne, Germany.,Klinik für Anästhesiologie und Intensivmedizin, Universität Duisburg-Essen und Universitätsklinikum Essen, Essen, Germany
| | - Jürgen Peters
- Klinik für Anästhesiologie und Intensivmedizin, Universität Duisburg-Essen und Universitätsklinikum Essen, Essen, Germany
| | - Ulrich H Frey
- Klinik für Anästhesiologie, operative Intensivmedizin, Schmerz- und Palliativmedizin, Marien Hospital Herne - Universitätsklinikum der Ruhr-Universität Bochum, Hölkeskampring 40, 44625, Herne, Germany. .,Klinik für Anästhesiologie und Intensivmedizin, Universität Duisburg-Essen und Universitätsklinikum Essen, Essen, Germany.
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Gomez LA, Shen Q, Doyle K, Vrosgou A, Velazquez A, Megjhani M, Ghoshal S, Roh D, Agarwal S, Park S, Claassen J, Kleinberg S. Classification of Level of Consciousness in a Neurological ICU Using Physiological Data. Neurocrit Care 2023; 38:118-128. [PMID: 36109448 PMCID: PMC9935697 DOI: 10.1007/s12028-022-01586-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 08/08/2022] [Indexed: 10/14/2022]
Abstract
BACKGROUND Impaired consciousness is common in intensive care unit (ICU) patients, and an individual's degree of consciousness is crucial to determining their care and prognosis. However, there are no methods that continuously monitor consciousness and alert clinicians to changes. We investigated the use of physiological signals collected in the ICU to classify levels of consciousness in critically ill patients. METHODS We studied 61 patients with subarachnoid hemorrhage (SAH) and 178 patients with intracerebral hemorrhage (ICH) from the neurological ICU at Columbia University Medical Center in a retrospective observational study of prospectively collected data. The level of consciousness was determined on the basis of neurological examination and mapped to comatose, vegetative state or unresponsive wakefulness syndrome (VS/UWS), minimally conscious minus state (MCS-), and command following. For each physiological signal, we extracted time-series features and performed classification using extreme gradient boosting on multiple clinically relevant tasks across subsets of physiological signals. We applied this approach independently on both SAH and ICH patient groups for three sets of variables: (1) a minimal set common to most hospital patients (e.g., heart rate), (2) variables available in most ICUs (e.g., body temperature), and (3) an extended set recorded mainly in neurological ICUs (absent for the ICH patient group; e.g., brain temperature). RESULTS On the commonly performed classification task of VS/UWS versus MCS-, we achieved an area under the receiver operating characteristic curve (AUROC) in the SAH patient group of 0.72 (sensitivity 82%, specificity 57%; 95% confidence interval [CI] 0.63-0.81) using the extended set, 0.69 (sensitivity 83%, specificity 51%; 95% CI 0.59-0.78) on the variable set available in most ICUs, and 0.69 (sensitivity 56%, specificity 78%; 95% CI 0.60-0.78) on the minimal set. In the ICH patient group, AUROC was 0.64 (sensitivity 56%, specificity 65%; 95% CI 0.55-0.74) using the minimal set and 0.61 (sensitivity 50%, specificity 80%; 95% CI 0.51-0.71) using the variables available in most ICUs. CONCLUSIONS We find that physiological signals can be used to classify states of consciousness for patients in the ICU. Building on this with intraday assessments and increasing sensitivity and specificity may enable alarm systems that alert physicians to changes in consciousness and frequent monitoring of consciousness throughout the day, both of which may improve patient care and outcomes.
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Affiliation(s)
- Louis A Gomez
- Stevens Institute of Technology, 1 Castle Point on Hudson, Hoboken, NJ, 07030, USA
| | - Qi Shen
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
| | - Kevin Doyle
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
| | - Athina Vrosgou
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
| | - Angela Velazquez
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
| | - Murad Megjhani
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
| | - Shivani Ghoshal
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
- New York Presbyterian Hospital, New York, NY, USA
| | - David Roh
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
- New York Presbyterian Hospital, New York, NY, USA
| | - Sachin Agarwal
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
- New York Presbyterian Hospital, New York, NY, USA
| | - Soojin Park
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
- New York Presbyterian Hospital, New York, NY, USA
| | - Jan Claassen
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, USA
- New York Presbyterian Hospital, New York, NY, USA
| | - Samantha Kleinberg
- Stevens Institute of Technology, 1 Castle Point on Hudson, Hoboken, NJ, 07030, USA.
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Bahouth MN, Negoita S, Tenberg A, Zink EK, Abshire MA, Davidson PM, Suarez JI, Szanton SL, Gottesman RF. Noninvasive cardiac output monitor to quantify hydration status in ischemic stroke patients: A feasibility study. J Neurol Sci 2022; 442:120413. [PMID: 36215798 DOI: 10.1016/j.jns.2022.120413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 08/25/2022] [Accepted: 09/04/2022] [Indexed: 10/31/2022]
Abstract
BACKGROUND Individuals who are dehydrated, volume contracted or both at the time of hospitalization for acute ischemic stroke have worse clinical outcomes than do individuals with optimal volume status. Currently, there is no gold standard method for measuring hydration status, except indirect markers of a volume contracted state (VCS) including elevated blood urea nitrogen (BUN)/creatinine ratio. We sought to test the feasibility and acceptability of a non-invasive cardiac output monitor (NICOM) for the measurement of hydration status in a group of hospitalized ischemic stroke patients, and explore the relationship with a common indirect laboratory-based measure of VCS. METHODS We performed a prospective observational feasibility study of hospitalized acute ischemic stroke patients. We collected hemodynamic parameters using the NICOM device before and after fluid auto-bolus via passive leg raise and BUN/creatinine ratio. Successful acquisition of relevant hemodynamic data was the primary objective of this study. We explored agreement between the NICOM results and BUN/creatinine ratio using Cohen's kappa statistic. RESULTS Thirty patients hospitalized with acute ischemic stroke were enrolled. We found that 29/30 patients tolerated assessment with NICOM. Hemodynamic data were collected in all 30 patients. Data capture took an average of 10 min(SD ± 112 s). Agreement between NICOM and BUN/creatinine ratio was 70%; (expected agreement 51%; kappa 0.38). Agreement was stronger in the cohort without history of diabetes (81% agreement, kappa 0.61). CONCLUSIONS NICOM assessment was feasible in hospitalized stroke patients. The identification of an objective, real-time measure of hydration status would be clinically useful, and could allow precise, goal-directed care.
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Affiliation(s)
- M N Bahouth
- Department of Neurology, Johns Hopkins School of Medicine, United States of America.
| | - S Negoita
- Department of Neurology, Johns Hopkins School of Medicine, United States of America
| | - A Tenberg
- Johns Hopkins Hospital, United States of America
| | - E K Zink
- Johns Hopkins Hospital, United States of America
| | - M A Abshire
- Johns Hopkins School of Nursing, United States of America
| | - P M Davidson
- Johns Hopkins School of Nursing, United States of America
| | - J I Suarez
- Department of Neurology, Johns Hopkins School of Medicine, United States of America
| | - S L Szanton
- Johns Hopkins School of Nursing, United States of America
| | - R F Gottesman
- Department of Neurology, Johns Hopkins School of Medicine, United States of America; Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, United States of America
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Dmytriiev D, Nazarchuk O, Melnychenko M, Levchenko B. Optimization of the target strategy of perioperative infusion therapy based on monitoring data of central hemodynamics in order to prevent complications. Front Med (Lausanne) 2022; 9:935331. [PMID: 36262276 PMCID: PMC9573976 DOI: 10.3389/fmed.2022.935331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 09/12/2022] [Indexed: 11/13/2022] Open
Abstract
Enhanced Recovery After Surgery (ERAS) protocols are increasingly used in the perioperative period around the world. The concept of goal-directed fluid therapy (GDT) is a key element of the ERAS protocols. Inadequate perioperative infusion therapy can lead to a number of complications, including the development of an infectious process, namely surgical site infections, pneumonia, urinary tract infections. Optimal infusion therapy is difficult to achieve with standard parameters (e.g., heart rate, blood pressure, central venous pressure), so there are various methods of monitoring central hemodynamics - from invasive, minimally invasive to non-invasive. The latter are increasingly used in clinical practice. The current evidence base shows that perioperative management, specifically the use of GDT guided by real-time, continuous hemodynamic monitoring, helps clinicians maintain a patient's optimal fluid balance. The manuscript presents the analytical data, which describe the benefits and basic principles of perioperative targeted infusion therapy based on central hemodynamic parameters to reduce the risk of complications.
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Affiliation(s)
- Dmytro Dmytriiev
- Department of Anesthesiology and Intensive Care, National Pirogov Memorial Medical University, Vinnytsya, Ukraine
| | - Oleksandr Nazarchuk
- Department of Microbiology, National Pirogov Memorial Medical University, Vinnytsya, Ukraine
| | - Mykola Melnychenko
- Department of Anesthesiology and Intensive Care, National Pirogov Memorial Medical University, Vinnytsya, Ukraine
| | - Bohdan Levchenko
- Department of Anesthesiology and Intensive Care, National Pirogov Memorial Medical University, Vinnytsya, Ukraine
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Reliability of bioreactance-derived hemodynamic monitoring during simulated sustained gravitational transitions induced by short-arm human centrifugation. Med Eng Phys 2022; 107:103868. [DOI: 10.1016/j.medengphy.2022.103868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 06/27/2022] [Accepted: 08/03/2022] [Indexed: 11/20/2022]
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12
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Hamilton DB, Jooma Z. Haemodynamic monitoring in patients undergoing high-risk surgery: a survey of current practice among anaesthesiologists at the University of the Witwatersrand. SOUTHERN AFRICAN JOURNAL OF ANAESTHESIA AND ANALGESIA 2022. [DOI: 10.36303/sajaa.2022.28.4.2614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- DB Hamilton
- Department of Anaesthesiology, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand,
South Africa
| | - Z Jooma
- Department of Anaesthesiology, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand,
South Africa
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Abstract
PURPOSE OF REVIEW The purpose of this article is to review various contemporary cardiac output (CO) measurement technologies available and their utility in critically ill patients. RECENT FINDINGS CO measurement devices can be invasive, minimally invasive, or noninvasive depending upon their method of CO measurement. All devices have pros and cons, with pulmonary artery catheter (PAC) being the gold standard. The invasive techniques are more accurate; however, their invasiveness can cause more complications. The noninvasive devices predict CO via mathematical modeling with several assumptions and are thus prone to errors in clinical situations. Recently, PAC has made a comeback into clinical practice especially in cardiac intensive care units (ICUs). Critical care echocardiography (CCE) is an upcoming tool that not only provides CO but also helps in differential diagnosis. Lack of proper training and nonavailability of equipment are the main hindrances to the wide adoption of CCE. SUMMARY PAC thermodilution for CO measurement is still gold standard and most suitable in patients with cardiac pathology and with experienced user. CCE offers an alternative to thermodilution and is suitable for all ICUs; however, structural training is required.
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Affiliation(s)
- Virendra K Arya
- Department of Anesthesiology, Perioperative and Pain Medicine, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada
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14
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Recco DP, Roy N, Gregory AJ, Lobdell KW. Invasive and noninvasive cardiovascular monitoring options for cardiac surgery. JTCVS OPEN 2022; 10:256-263. [PMID: 36004243 PMCID: PMC9390282 DOI: 10.1016/j.xjon.2022.02.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 02/17/2022] [Indexed: 11/10/2022]
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15
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Caballer A, Nogales S, Gruartmoner G, Mesquida J. Monitorización hemodinámica en la sepsis y el shock séptico. Med Intensiva 2022. [DOI: 10.1016/j.medin.2022.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Caballer A, Nogales S, Gruartmoner G, Mesquida J. [Haemodynamic monitoring in sepsis and septic shock]. Med Intensiva 2022; 46 Suppl 1:38-48. [PMID: 38341259 DOI: 10.1016/j.medine.2022.02.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 02/23/2022] [Accepted: 02/26/2022] [Indexed: 02/12/2024]
Abstract
Cardiovascular disturbances associated with sepsis cause hypoperfusion situations, which will negatively impact these patients' prognosis. The aim of haemodynamic monitoring is to guide the detection and correction of this hypoperfusion, and assist in decision making in optimising oxygen transport to tissues, primarily by manipulating cardiac output. This review seeks to summarise the different parameters of haemodynamic monitoring, the objectives of resuscitation, the physiological parameters, and the tools available to us for appropriate cardiac output manipulation.
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Affiliation(s)
- Alba Caballer
- Àrea de Crítics, Hospital Universitari Parc Taulí, Sabadell, Barcelona, España.
| | - Sara Nogales
- Àrea de Crítics, Hospital Universitari Parc Taulí, Sabadell, Barcelona, España
| | - Guillem Gruartmoner
- Àrea de Crítics, Hospital Universitari Parc Taulí, Sabadell, Barcelona, España
| | - Jaume Mesquida
- Àrea de Crítics, Hospital Universitari Parc Taulí, Sabadell, Barcelona, España
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Kenny JÉS, Barjaktarevic I, Eibl AM, Parrotta M, Long BF, Elfarnawany M, Eibl JK. Temporal concordance between pulse contour analysis, bioreactance and carotid doppler during rapid preload changes. PLoS One 2022; 17:e0265711. [PMID: 35320307 PMCID: PMC8942202 DOI: 10.1371/journal.pone.0265711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/07/2022] [Indexed: 11/18/2022] Open
Abstract
PURPOSE We describe the temporal concordance of 3 hemodynamic monitors. MATERIALS AND METHODS Healthy volunteers performed preload changes while simultaneously wearing a non-invasive, pulse-contour stroke volume (SV) monitor, a bioreactance SV monitor and a wireless, wearable Doppler ultrasound patch over the common carotid artery. The sensitivity and specificity for detecting preload change over 3 temporal windows (early, middle and late) was assessed. RESULTS 40 preload changes were recorded in total (20 increase, 20 decrease). Immediately, the wearable Doppler had high sensitivity (100%) and specificity (100%) for detecting preload change with an area under the receiver operator curve (AUROC) of 0.98 for both velocity time integral (VTI, 10.5% threshold) and corrected flow time (FTc, 2.5% threshold). The sensitivity, specificity and AUROC for non-invasive pulse contour were equally good (9% SV threshold). For bioreactance, a 13% SV threshold immediately detected preload change with a sensitivity, specificity and AUROC of 60%, 95% and 0.75, respectively. After two SV outputs following preload change, the sensitivity, specificity and AUROC of bioreactance improved to 70%, 90% and 0.85, respectively. CONCLUSIONS Carotid Doppler ultrasound and non-invasive pulse contour detected rapid hemodynamic change with equal accuracy; bioreactance improved over time. Algorithm-lag should be considered when interpreting clinical studies.
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Affiliation(s)
| | - Igor Barjaktarevic
- Division of Pulmonary and Critical Care, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States of America
| | - Andrew M. Eibl
- Health Sciences North Research Institute, Sudbury, ON, Canada
| | | | - Bradley F. Long
- Health Sciences North Research Institute, Sudbury, ON, Canada
- Northern Ontario School of Medicine, Sudbury, ON, Canada
| | - Mai Elfarnawany
- Health Sciences North Research Institute, Sudbury, ON, Canada
| | - Joseph K. Eibl
- Health Sciences North Research Institute, Sudbury, ON, Canada
- Northern Ontario School of Medicine, Sudbury, ON, Canada
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Norepinephrine versus phenylephrine infusion for preventing postspinal hypotension during cesarean section for twin pregnancy: a double-blinded randomized controlled clinical trial. BMC Anesthesiol 2022; 22:17. [PMID: 34998371 PMCID: PMC8742356 DOI: 10.1186/s12871-022-01562-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/31/2021] [Indexed: 02/08/2023] Open
Abstract
Background Compared with singleton pregnancy, twin gestation is featured by a greater increase in cardiac output. Therefore, norepinephrine might be more suitable than phenylephrine for maintaining blood pressure during cesarean section for twins, as phenylephrine causes reflex bradycardia and a resultant decrease in cardiac output. This study was to determine whether norepinephrine was superior to phenylephrine in maintaining maternal hemodynamics during cesarean section for twins. Methods Informed consent was obtained from all the patients before enrollment. In this double-blinded, randomized clinical trial, 100 parturients with twin gestation undergoing cesarean section with spinal anesthesia were randomized to receive prophylactic norepinephrine (3.2 μg/min) or phenylephrine infusion (40 μg/min). The primary outcome was the change of heart rate and blood pressure during the study period. The secondary outcomes were to compare maternal complications, neonatal outcomes, Apgar scores and umbilical blood acid-base status between the two vasopressors. Results There was no significant difference observed for the change of heart rate between two vasopressors. The mean standardized area under the curve of heart rate was 78 ± 12 with norepinephrine vs. 74 ± 11 beats/min with phenylephrine (mean difference 4.4, 95%CI − 0.1 to 9.0; P = .0567). The mean standardized area under the curve of systolic blood pressure (SBP) was significantly lower in parturients with norepinephrine, as the mean of differences in standardized AUC of SBP was 6 mmHg, with a 95% CI from 2 to 9 mmHg (P = .0013). However, requirements of physician interventions for correcting maternal hemodynamical abnormalities (temporary cessation of vasopressor infusion for reactive hypertension, rescuing vasopressor bolus for hypotension and atropine for heart rate less < 50 beats/min) and neonatal outcomes were also not significantly different between two vasopressors. Conclusion Infusion of norepinephrine was not associated with less overall decrease in heart rate during cesarean section for twins, compared with phenylephrine. Trial registration Chinese Clinical Trial Registry (ChiCTR1900021281).
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A performance comparison of the most commonly used minimally invasive monitors of cardiac output. Can J Anaesth 2021; 68:1668-1682. [PMID: 34374024 DOI: 10.1007/s12630-021-02085-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 06/25/2021] [Accepted: 06/28/2021] [Indexed: 10/20/2022] Open
Abstract
BACKGROUND Shock is common in critically ill and injured patients. Survival during shock is highly dependent on rapid restoration of tissue oxygenation with therapeutic goals based on cardiac output (CO) optimization. Despite the clinical availability of numerous minimally invasive monitors of CO, limited supporting performance data are available. METHODS Following approval of the University of Saskatchewan Animal Research Ethics Board, we assessed the performance and trending ability of PiCCOplus™, FloTrac™, and CardioQ-ODM™ across a range of CO states in pigs. In addition, we assessed the ability of invasive mean arterial blood pressure (iMAP) to follow changes in CO using a periaortic transit-time flow probe as the reference method. Statistical analysis was performed with function-fail, bias and precision, percent error, and linear regression at all flow, low-flow (> 1 standard deviation [SD] below the mean), and high-flow (> 1 SD above the mean) CO conditions. RESULTS We made a total of 116,957 paired CO measurements. The non-invasive CO monitors often failed to provide a CO value (CardioQ-ODM: 40.6% failed measurements; 99% confidence interval [CI], 38.5 to 42.6; FloTrac: 9.6% failed measurements; 99% CI, 8.7 to 10.5; PiCCOplus: 4.7% failed measurements; 99% CI, 4.5 to 4.9; all comparisons, P < 0.001). The invasive mean arterial pressure provided zero failures, failing less often than any of the tested CO monitors (all comparisons, P < 0.001). The PiCCOplus was most interchangeable with the flow probe at all flow states: PiCCOplus (20% error; 99% CI, 19 to 22), CardioQ-ODM (25% error; 99% CI, 23 to 27), FloTrac (34% error; 99% CI, 32 to 38) (all comparisons, P < 0.001). At low-flow states, CardioQ-ODM (43% error; 99% CI, 32 to 63) and Flotrac (45% error; 99% CI, 33 to 70) had similar interchangeability (P = 0.07), both superior to PiCCOplus (48% error; 99% CI, 42 to 60) (P < 0.001). Regarding CO trending, the CardioQ-ODM (correlation coefficient, 0.82; 99% CI, 0.81 to 0.83) was statistically superior to other monitors including iMAP, but at low flows iMAP (correlation coefficient, 0.58; 99% CI, 0.58 to 0.60) was superior to all minimally invasive CO monitors (all comparisons P < 0.001). CONCLUSIONS None of the minimally invasive monitors of CO performed well at all tested flows. Invasive mean arterial blood pressure most closely tracked CO change at critical flow states.
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Souza RSE, Melo WBD, Freire CMV, Vilas Boas WW. Comparative study between suprasternal and apical windows: a user-friendly cardiac output measurement for the anesthesiologist. Braz J Anesthesiol 2021:S0104-0014(21)00264-5. [PMID: 34246688 PMCID: PMC10362443 DOI: 10.1016/j.bjane.2021.02.063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 02/18/2021] [Accepted: 02/27/2021] [Indexed: 10/20/2022] Open
Abstract
INTRODUCTION Transthoracic echocardiography is a safe and readily available tool for noninvasive monitoring of Cardiac Output (CO). The use of the suprasternal window situated at the sternal notch can be an alternative approach for estimating blood flow. The present study aimed to compare two methods of CO calculation. We compared the descending aorta Velocity-Time Integral (VTI) measurement from the suprasternal window view with the standard technique to determine CO that uses VTI measurements from the LVOT (Left Ventricular Outflow Tract) view. We also aimed to find out whether after basic training a non-echocardiographer operator can obtain reproducible measurements of VTI using this approach. METHODS In the first part of the study, 26 patients without known cardiovascular diseases were evaluated and VTI data were acquired from the suprasternal window by a non-echocardiographer and an echocardiographer. Next, 17 patients were evaluated by an echocardiographer only and VTI and CO measurements were obtained from suprasternal and apical windows. Data were analyzed using the Bland and Altman method (BA), correlation and regression. RESULTS We found a strong correlation between measurements obtained by a non-expert and an expert echocardiographer and detected that an inexperienced trainee can acquire VTI measurements from the suprasternal window view. Regarding agreement between CO measurements, data obtained showed a positive correlation and the Bland and Altman analysis presented a total variation of 38.9%. CONCLUSION Regarding accuracy, it is likely that TTE (Transthoracic Echocardiogram) measurements of CO from the suprasternal window view are comparable to other minimally invasive techniques currently available. Due to its user-friendliness and low cost, it can be a convenient technique for obtaining perioperative hemodynamic measurements, even by inexperienced operators.
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Affiliation(s)
- Rafaela Souto E Souza
- Hospital das Clínicas da Universidade Federal de Minas Gerais (HC/UFMG), Belo Horizonte, MG, Brazil.
| | - Wendhell Barros de Melo
- Hospital das Clínicas da Universidade Federal de Minas Gerais (HC/UFMG), Belo Horizonte, MG, Brazil
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21
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Ansari S, Golbus JR, Tiba MH, McCracken B, Wang L, Aaronson KD, Ward KR, Najarian K, Oldham KR. Detection of Low Cardiac Index using a Polyvinylidene Fluoride-Based Wearable Ring and Convolutional Neural Networks. IEEE SENSORS JOURNAL 2021; 21:14281-14289. [PMID: 34504397 PMCID: PMC8423366 DOI: 10.1109/jsen.2020.3022273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
This study investigated the use of a wearable ring made of polyvinylidene fluoride film to identify a low cardiac index (≤2 L/min). The waveform generated by the ring contains patterns that may be indicative of low blood pressure and/or high vascular resistance, both of which are markers of a low cardiac index. In particular, the waveform contains reflection waves whose timing and amplitude are correlated with pulse travel time and vascular resistance, respectively. Hence, the pattern of the waveform is expected to vary in response to changes in blood pressure and vascular resistance. By analyzing the morphology of the waveform, our aim was to create a tool to identify patients with low cardiac index. This was done using a convolutional neural network which was trained on data from animal models. The model was then tested on waveforms that were collected from patients undergoing pulmonary artery catheterization. The results indicate high accuracy in classifying patients with a low cardiac index, achieving an area under the receiver operating characteristics and precision-recall curves of 0.88 and 0.71, respectively.
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Affiliation(s)
- Sardar Ansari
- Department of Emergency Medicine, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Jessica R Golbus
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109 USA
| | - Mohamad H Tiba
- Department of Emergency Medicine, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Brendan McCracken
- Department of Emergency Medicine, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Lu Wang
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Keith D Aaronson
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109 USA
| | - Kevin R Ward
- Department of Emergency Medicine and the Biomedical Engineering Department, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Kayvan Najarian
- Department of Computational Medicine and Bioinformatics, the Department of Emergency Medicine and the Electrical Engineering and Computer Science Department, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Kenn R Oldham
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
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22
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Abstract
PURPOSE OF REVIEW The current article reviews recent findings on the monitoring and hemodynamic support of septic shock patients. RECENT FINDINGS The ultimate goal of hemodynamic resuscitation is to restore tissue oxygenation. A multimodal approach combining global and regional markers of tissue hypoxia seems appropriate to guide resuscitation. Several multicenter clinical trials have provided evidence against an aggressive fluid resuscitation strategy. Fluid administration should be personalized and based on the evidence of fluid responsiveness. Dynamic indices have proven to be highly predictive of responsiveness. Recent data suggest that balanced crystalloids may be associated with less renal failure. When fluid therapy is insufficient, a multimode approach with different types of vasopressors has been suggested as an initial approach. Dobutamine remains the firs inotropic option in patients with persistent hypotension and decrease ventricular systolic function. Calcium sensitizer and phosphodiesterase inhibitors may be considered, but evidence is still limited. Veno-arterial extracorporeal membrane oxygenation may be considered in selected unresponsive patients, particularly with myocardial depression, and in a highly experienced center. SUMMARY Resuscitation should be personalized and based on global and regional markers of tissue hypoxia as well as the fluid responsiveness indices. The beneficial effect of multimode approach with different types of vasopressors, remains to be determined.
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Kim KK, Krause M, Brandes IF, Khanna AK, Bartels K. Transesophageal echocardiography for perioperative management in thoracic surgery. Curr Opin Anaesthesiol 2021; 34:7-12. [PMID: 33315644 DOI: 10.1097/aco.0000000000000947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
PURPOSE OF REVIEW Perioperative transesophageal echocardiography (TEE) is most often employed during cardiac surgery. This review will summarize some of the recent findings relevant to TEE utilization during thoracic surgical procedures. RECENT FINDINGS Hemodynamic monitoring is a key component of goal-directed fluid therapy, which is also becoming more common for management of thoracic surgical procedures. Although usually not required for the anesthetic management of common thoracic surgeries, TEE is frequently used during lung transplantation and pulmonary thromboendarterectomy. Few clinical studies support current practice patterns, and most recommendations are based on expert opinion. SUMMARY Currently, routine use of TEE in thoracic surgery is often limited to specific high-risk patients and/or procedures. As in other perioperative settings, TEE may be utilized to elucidate the reasons for acute hemodynamic instability without apparent cause. Contraindications to TEE apply and have to be taken into consideration before performing a TEE on a thoracic surgical patient.
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Affiliation(s)
- Kevin K Kim
- Department of Anesthesiology, University of Colorado, School of Medicine, Aurora, Colorado, USA
| | - Martin Krause
- Department of Anesthesiology, University of Colorado, School of Medicine, Aurora, Colorado, USA
| | - Ivo F Brandes
- Universitätsmedizin Göttingen, Klinik für Anästhesiologie, Göttingen, Germany
| | - Ashish K Khanna
- Department of Anesthesiology, Section on Critical Care Medicine, Wake Forest University, School of Medicine, Winston-Salem, North Carolina, USA
- Outcomes Research Consortium, Cleveland, OH, USA
| | - Karsten Bartels
- Department of Anesthesiology, University of Colorado, School of Medicine, Aurora, Colorado, USA
- Outcomes Research Consortium, Cleveland, OH, USA
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Kanazawa H, Maeda T, Miyazaki E, Hotta N, Ito S, Ohnishi Y. Accuracy and Trending Ability of Blood Pressure and Cardiac Index Measured by ClearSight System in Patients With Reduced Ejection Fraction. J Cardiothorac Vasc Anesth 2020; 34:3293-3299. [DOI: 10.1053/j.jvca.2020.03.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 03/22/2020] [Accepted: 03/24/2020] [Indexed: 01/01/2023]
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Abstract
PURPOSE OF REVIEW To appraise the basic and more advanced methods available for hemodynamic monitoring, and describe the definitions and criteria for the use of hemodynamic variables. RECENT FINDINGS The hemodynamic assessment in critically ill patients suspected of circulatory shock follows a step-by-step algorithm to help determine diagnosis and prognosis. Determination of accurate diagnosis and prognosis in turn is crucial for clinical decision-making. Basic monitoring involving clinical examination in combination with hemodynamic variables obtained with an arterial catheter and a central venous catheter may be sufficient for the majority of patients with circulatory shock. In case of uncertainty of the underlying cause or to guide treatment in severe shock may require additional advanced hemodynamic technologies, and each is utilized for different indications and has specific limitations. Future developments include refining the clinical examination and performing studies that demonstrate better patient outcomes by targeting hemodynamic variables using advanced hemodynamic monitoring. SUMMARY Determination of accurate diagnosis and prognosis for patients suspected of circulatory shock is essential for optimal decision-making. Numerous techniques are available, and each has its specific indications and value.
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Technological Assessment and Objective Evaluation of Minimally Invasive and Noninvasive Cardiac Output Monitoring Systems. Anesthesiology 2020; 133:921-928. [PMID: 32773696 DOI: 10.1097/aln.0000000000003483] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Bachmann KF, Zwicker L, Nettelbeck K, Casoni D, Heinisch PP, Jenni H, Haenggi M, Berger D. Assessment of Right Heart Function during Extracorporeal Therapy by Modified Thermodilution in a Porcine Model. Anesthesiology 2020; 133:879-891. [PMID: 32657798 DOI: 10.1097/aln.0000000000003443] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Veno-arterial extracorporeal membrane oxygenation therapy is a growing treatment modality for acute cardiorespiratory failure. Cardiac output monitoring during veno-arterial extracorporeal membrane oxygenation therapy remains challenging. This study aims to validate a new thermodilution technique during veno-arterial extracorporeal membrane oxygenation therapy using a pig model. METHODS Sixteen healthy pigs were centrally cannulated for veno-arterial extracorporeal membrane oxygenation, and precision flow probes for blood flow assessment were placed on the pulmonary artery. After chest closure, cold boluses of 0.9% saline solution were injected into the extracorporeal membrane oxygenation circuit, right atrium, and right ventricle at different extracorporeal membrane oxygenation flows (4, 3, 2, 1 l/min). Rapid response thermistors in the extracorporeal membrane oxygenation circuit and pulmonary artery recorded the temperature change. After calculating catheter constants, the distributions of injection volumes passing each circuit were assessed and enabled calculation of pulmonary blood flow. Analysis of the exponential temperature decay allowed assessment of right ventricular function. RESULTS Calculated blood flow correlated well with measured blood flow (r2 = 0.74, P < 0.001). Bias was -6 ml/min [95% CI ± 48 ml/min] with clinically acceptable limits of agreement (668 ml/min [95% CI ± 166 ml/min]). Percentage error varied with extracorporeal membrane oxygenation blood flow reductions, yielding an overall percentage error of 32.1% and a percentage error of 24.3% at low extracorporeal membrane oxygenation blood flows. Right ventricular ejection fraction was 17 [14 to 20.0]%. Extracorporeal membrane oxygenation flow reductions increased end-diastolic and end-systolic volumes with reductions in pulmonary vascular resistance. Central venous pressure and right ventricular ejection fractions remained unchanged. End-diastolic and end-systolic volumes correlated highly (r2 = 0.98, P < 0.001). CONCLUSIONS Adapted thermodilution allows reliable assessment of cardiac output and right ventricular behavior. During veno-arterial extracorporeal membrane oxygenation weaning, the right ventricle dilates even with stable function, possibly because of increased venous return. EDITOR’S PERSPECTIVE
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Okwose NC, Bouzas-Cruz N, Fernandez OG, Koshy A, Green T, Woods A, Robinson-Smith N, Tovey S, Mcdiarmid A, Parry G, Schueler S, Macgowan GA, Jakovljevic DG. Validity of Hemodynamic Monitoring Using Inert Gas Rebreathing Method in Patients With Chronic Heart Failure and Those Implanted With a Left Ventricular Assist Device. J Card Fail 2020; 27:414-418. [PMID: 33035686 DOI: 10.1016/j.cardfail.2020.09.479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 08/24/2020] [Accepted: 09/29/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVE The present study assessed agreement between resting cardiac output estimated by inert gas rebreathing (IGR) and thermodilution methods in patients with heart failure and those implanted with a left ventricular assist device (LVAD). METHODS AND RESULTS Hemodynamic measurements were obtained in 42 patients, 22 with chronic heart failure and 20 with implanted continuous flow LVAD (34 males, aged 50 ± 11 years). Measurements were performed at rest using thermodilution and IGR methods. Cardiac output derived by thermodilution and IGR were not significantly different in LVAD (4.4 ± 0.9 L/min vs 4.7 ± 0.8 L/min, P = .27) or patients with heart failure (4.4 ± 1.4 L/min vs 4.5 ± 1.3 L/min, P = .75). There was a strong relationship between thermodilution and IGR cardiac index (r = 0.81, P = .001) and stroke volume index (r = 0.75, P = .001). Bland-Altman analysis showed acceptable limits of agreement for cardiac index derived by thermodilution and IGR, namely, the mean difference (lower and upper limits of agreement) for patients with heart failure -0.002 L/min/m2 (-0.65 to 0.66 L/min/m2), and -0.14 L/min/m2 (-0.78 to 0.49 L/min/m2) for patients with LVAD. CONCLUSIONS IGR is a valid method for estimating cardiac output and should be used in clinical practice to complement the evaluation and management of chronic heart failure and patients with an LVAD.
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Affiliation(s)
- Nduka C Okwose
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Noelia Bouzas-Cruz
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Oscar Gonzalez Fernandez
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Aaron Koshy
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Thomas Green
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Andrew Woods
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Nicola Robinson-Smith
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Sian Tovey
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Adam Mcdiarmid
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Gareth Parry
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Stephan Schueler
- Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Guy A Macgowan
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK; Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Djordje G Jakovljevic
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK; Departments of Cardiology and Cardiothoracic Surgery, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK; Cardiovascular Research Division, Faculty of Health and Life Sciences, Coventry University, Coventry, UK.
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Pandhita BAW, Okwose NC, Koshy A, Fernández ÓG, Cruz NB, Eggett C, Velicki L, Popovic D, MacGowan GA, Jakovljevic DG. Noninvasive Assessment of Cardiac Output in Advanced Heart Failure and Heart Transplant Candidates Using the Bioreactance Method. J Cardiothorac Vasc Anesth 2020; 35:1776-1781. [PMID: 33059979 DOI: 10.1053/j.jvca.2020.09.109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 08/18/2020] [Accepted: 09/16/2020] [Indexed: 11/11/2022]
Abstract
OBJECTIVES The aim of the present study was to assess the validity and trending ability of the bioreactance method in estimating cardiac output at rest and in response to stress in advanced heart failure patients and heart transplant candidates. DESIGN This was a prospective single-center study. SETTING This study was conducted at the heart transplant center at the Freeman Hospital, Newcastle upon Tyne, UK. PARTICIPANTS Eighteen patients with advanced chronic heart failure due to reduced left ventricular ejection fraction (19 ± 7%), and peak oxygen consumption 12.3 ± 3.9 mL/kg/min. INTERVENTIONS Participants underwent right heart catheterization using the Swan-Ganz catheter. MEASUREMENTS AND MAIN RESULTS Cardiac output was measured simultaneously using thermodilution and bioreactance at rest and during active straight leg raise test to volitional exertion. There was no significant difference in cardiac index values obtained by the thermodilution and bioreactance methods (2.26 ± 0.59 v 2.38 ± 0.50 L/min, p > 0.05) at rest and peak straight leg raise test (2.92 ± 0.77 v 3.01 ± 0.66 L/min, p > 0.05). In response to active leg raise test, thermodilution cardiac output increased by 22% and bioreactance by 21%. There was also a strong relationship between cardiac outputs from both methods at rest (r = 0.88, p < 0.01) and peak straight leg raise test (r = 0.92, p < 0.01). Cartesian plot analysis showed good trending ability of bioreactance compared with thermodilution (concordance rate = 93%) CONCLUSIONS: `Cardiac output measured by the bioreactance method is comparable to that from the thermodilution method. Bioreactance method may be used in clinical practice to assess hemodynamics and improve management of advanced heart failure patients undergoing heart transplant assessment.
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Affiliation(s)
- Bashar A W Pandhita
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Nduka C Okwose
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Aaron Koshy
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Óscar G Fernández
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Noelia B Cruz
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Christopher Eggett
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Lazar Velicki
- Faculty of Medicine, University of Novi Sad, and Department of Cardiovascular Surgery, Institute of Cardiovascular Diseases Vojvodina, Novi Sad, Serbia
| | - Dejana Popovic
- Division of Cardiology, University Clinical Centre Serbia, Faculty of Pharmacy University of Belgrade, Belgrade, Serbia
| | - Guy A MacGowan
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
| | - Djordje G Jakovljevic
- Cardiovascular Research, Clinical and Translational and Biosciences Research Institutes, Faculty of Medical Sciences, Newcastle University and Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom.
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Sengupta SP, Mungulmare K, Okwose NC, MacGowan GA, Jakovljevic DG. Comparison of cardiac output estimates by echocardiography and bioreactance at rest and peak dobutamine stress test in heart failure patients with preserved ejection fraction. Echocardiography 2020; 37:1603-1609. [PMID: 32949037 DOI: 10.1111/echo.14836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/25/2020] [Accepted: 08/02/2020] [Indexed: 11/28/2022] Open
Abstract
PURPOSE To assess the agreement between cardiac output estimated by two-dimensional echocardiography and bioreactance methods at rest and during dobutamine stress test in heart failure patients with preserved left ventricular ejection fraction (HFpEF). METHODS Hemodynamic measurements were assessed in 20 stable HFpEF patients (12 females; aged 61 ± 7 years) using echocardiography and bioreactance methods during rest and dobutamine stress test at increment dosages of 5, 10, 15, and 20 μg/kg/min until maximal dose was achieved or symptoms and sign occurred, that is, chest pain, abnormal blood pressure elevation, breathlessness, ischemic changes, or arrhythmia. RESULTS Resting cardiac output and cardiac index estimated by bioreactance and echocardiography were not significantly different. At peak dobutamine stress test, cardiac output and cardiac index estimated by echocardiography and bioreactance were significantly different (7.06 ± 1.43 vs 5.71 ± 1.59 L/min, P < .01; and 4.27 ± 0.67 vs 3.43 ± 0.87 L/m2 /min; P < .01) due to the significant differences in stroke volume. There was a strong positive relationship between cardiac outputs obtained by the two methods at peak dobutamine stress (r = .79, P < .01). The mean difference (lower and upper limits of agreement) between bioreactance and echocardiography cardiac outputs at rest and peak dobutamine stress was -0.45 (1.71 to -2.62) L/min and -1.35 (0.60 to -3.31) L/min, respectively. CONCLUSION Bioreactance and echocardiography methods provide different cardiac output values at rest and during stress thus cannot be used interchangeably. Ability to continuously monitor key hemodynamic variables such as cardiac output, stroke volume, and heart rate is the major advantage of bioreactance method.
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Affiliation(s)
- Shantanu P Sengupta
- Cardiology, Sengupta Hospital and Research Institute, Ravinagar Nagpur, Maharashtra, India.,Faculty of Medical Sciences, Cardiovascular Research Translational and Clinical Research Institute, Newcastle upon Tyne, UK
| | - Kunda Mungulmare
- Cardiology, Sengupta Hospital and Research Institute, Ravinagar Nagpur, Maharashtra, India
| | - Nduka C Okwose
- Faculty of Medical Sciences, Cardiovascular Research Translational and Clinical Research Institute, Newcastle upon Tyne, UK
| | - Guy A MacGowan
- Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK.,Faculty of Medical Sciences, Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Djordje G Jakovljevic
- Faculty of Medical Sciences, Cardiovascular Research Translational and Clinical Research Institute, Newcastle upon Tyne, UK.,Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK.,Faculty of Health and Life Sciences, Coventry University, Coventry, UK
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Piuzzi E, Pisa S, Pittella E, Podestà L, Sangiovanni S. Wearable Belt With Built-In Textile Electrodes for Cardio-Respiratory Monitoring. SENSORS 2020; 20:s20164500. [PMID: 32806534 PMCID: PMC7472108 DOI: 10.3390/s20164500] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 08/02/2020] [Accepted: 08/10/2020] [Indexed: 12/27/2022]
Abstract
Unobtrusive and continuous monitoring of vital signs is becoming more and more important both for patient monitoring in the home environment and for sports activity tracking. Even though many gadgets and clinical systems exist, the need for simple, low-cost and easily applicable solutions still remains, especially in view of a more widespread use within everyone’s reach. The paper presents a fully wearable and wireless sensorized belt, suitable to simultaneously acquire respiratory and cardiac signals employing a single acquisition channel. The adopted method relies on a 50-kHz current injected in the subject thorax through a couple of textile electrodes and on envelope detection of the trans-thoracic voltage acquired from a couple of different embedded electrodes. The resulting signal contains both the baseband electrocardiogram (ECG) signal and the trans-thoracic impedance signal, which encodes respiratory acts. The two signals can be easily separated through suitable filtering and the cardio–respiratory rates extracted. The proposed solution yields performances comparable to those of a spirometer and a two-lead ECG. The whole system, with a realization cost below 100 €, a wireless interface, and several hours (or even days) of autonomy, is a suitable candidate for everyday use, especially if complemented by motion artifact removal techniques, currently under implementation.
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Affiliation(s)
- Emanuele Piuzzi
- Department of Information Engineering, Electronics and Telecommunications (DIET), Sapienza University of Rome, via Eudossiana 18, 00184 Rome, Italy;
- Correspondence:
| | - Stefano Pisa
- Department of Information Engineering, Electronics and Telecommunications (DIET), Sapienza University of Rome, via Eudossiana 18, 00184 Rome, Italy;
| | - Erika Pittella
- Department of Legal and Economic Sciences, Pegaso University, via di S. Pantaleo 66, 00186 Rome, Italy;
| | - Luca Podestà
- Department of Astronautics, Electrical and Energetics Engineering (DIAEE), Sapienza University of Rome, via Eudossiana 18, 00184 Rome, Italy; (L.P.); (S.S.)
| | - Silvia Sangiovanni
- Department of Astronautics, Electrical and Energetics Engineering (DIAEE), Sapienza University of Rome, via Eudossiana 18, 00184 Rome, Italy; (L.P.); (S.S.)
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Vignon P. Continuous cardiac output assessment or serial echocardiography during septic shock resuscitation? ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:797. [PMID: 32647722 PMCID: PMC7333154 DOI: 10.21037/atm.2020.04.11] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Septic shock is the leading cause of cardiovascular failure in the intensive care unit (ICU). Cardiac output is a primary component of global oxygen delivery to organs and a sensitive parameter of cardiovascular failure. Any mismatch between oxygen delivery and rapidly varying metabolic demand may result in tissue dysoxia, hence organ dysfunction. Since the intricate alterations of both vascular and cardiac function may rapidly and widely change over time, cardiac output should be measured repeatedly to characterize the type of shock, select the appropriate therapeutic intervention, and evaluate patient's response to therapy. Among the numerous techniques commercially available for measuring cardiac output, transpulmonary thermodilution (TPT) provides a continuous monitoring with external calibration capability, whereas critical care echocardiography (CCE) offers serial hemodynamic assessments. CCE allows early identification of potential sources of inaccuracy of TPT, including right ventricular failure, severe tricuspid or left-sided regurgitations, intracardiac shunt, very low flow states, or dynamic left ventricular outflow tract obstruction. In addition, CCE has the unique advantage of depicting the distinct components generating left ventricular stroke volume (large cavity size vs. preserved contractility), providing information on left ventricular diastolic properties and filling pressures, and assessing pulmonary artery pressure. Since inotropes may have deleterious effects if misused, their initiation should be based on the documentation of a cardiac dysfunction at the origin of the low flow state by CCE. Experts widely advocate using CCE as a first-line modality to initially evaluate the hemodynamic profile associated with shock, as opposed to more invasive techniques. Repeated assessments of both the efficacy (amplitude of the positive response) and tolerance (absence of side-effect) of therapeutic interventions are required to best guide patient management. Overall, TPT allowing continuous tracking of cardiac output variations and CCE appear complementary rather than mutually exclusive in patients with septic shock who require advanced hemodynamic monitoring.
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Affiliation(s)
- Philippe Vignon
- Medical-Surgical Intensive Care Unit, Dupuytren Teaching hospital, Limoges, France.,Inserm CIC 1435, Dupuytren Teaching hospital, Limoges, France.,Faculty of Medicine, University of Limoges, Limoges, France
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Baysan M, Arbous MS, Mik EG, Juffermans NP, van der Bom JG. Study protocol and pilot results of an observational cohort study evaluating effect of red blood cell transfusion on oxygenation and mitochondrial oxygen tension in critically ill patients with anaemia: the INsufficient Oxygenation in the Intensive Care Unit (INOX ICU-2) study. BMJ Open 2020; 10:e036351. [PMID: 32423938 PMCID: PMC7239524 DOI: 10.1136/bmjopen-2019-036351] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 04/06/2020] [Accepted: 04/17/2020] [Indexed: 01/12/2023] Open
Abstract
INTRODUCTION The recently developed protoporphyrin IX-triple state lifetime technique measures mitochondrial oxygenation tension (mitoPO2) in vivo at the bedside. MitoPO2might be an early indicator of oxygen disbalance in cells of critically ill patients and therefore may support clinical decisions regarding red blood cell (RBC) transfusion. We aim to investigate the effect of RBC transfusion and the associated changes in haemoglobin concentration on mitoPO2 and other physiological measures of tissue oxygenation and oxygen balance in critically ill patients with anaemia. We present the protocol and pilot results for this study. METHODS AND ANALYSIS We perform a prospective multicentre observational study in three mixed intensive care units in the Netherlands with critically ill patients with anaemia in whom an RBC transfusion is planned. The skin of the anterior chest wall of the patients is primed with a 5-aminolevulinic acid patch for 4 hours for induction of mitochondrial protoporphyrin-IX to enable measurements of mitoPO2, which is done with the COMET monitoring device. At multiple predefined moments, before and after RBC transfusion, we assess mitoPO2 and other physiological parameters of oxygen balance and tissue oxygenation. Descriptive statistics will be used to describe the data. A linear mixed-effect model will be used to study the association between RBC transfusion and mitoPO2 and other traditional parameters of oxygenation, oxygen delivery and oxygen balance. Missing data will be imputed using multiple imputation methods. ETHICS AND DISSEMINATION The institutional ethics committee of each participating centre approved the study (reference P16.303), which will be conducted according to the 1964 Helsinki declaration and its later amendments. The results will be submitted for publication in peer-reviewed journals and presented at scientific conferences. TRIAL REGISTRATION NUMBER NCT03092297.
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Affiliation(s)
- Meryem Baysan
- Department of Intensive Care, LUMC, Leiden, The Netherlands
- Clinical Transfusion Research, Sanquin Research Clinical Transfusion Research, Leiden, Zuid-Holland, The Netherlands
- Department of Clinical Epidemiology, LUMC, Leiden, Zuid-Holland, The Netherlands
| | - Mendi S Arbous
- Department of Intensive Care, LUMC, Leiden, The Netherlands
- Department of Clinical Epidemiology, LUMC, Leiden, Zuid-Holland, The Netherlands
| | - Egbert G Mik
- Department of Anesthesiology, Laboratory of Experimental Anesthesiology, Erasmus Medical Center, Rotterdam, Zuid-Holland, The Netherlands
| | - Nicole P Juffermans
- Department of Intensive Care, Amsterdam UMC - Location AMC, Amsterdam, North Holland, The Netherlands
| | - Johanna G van der Bom
- Clinical Transfusion Research, Sanquin Research Clinical Transfusion Research, Leiden, Zuid-Holland, The Netherlands
- Department of Clinical Epidemiology, LUMC, Leiden, Zuid-Holland, The Netherlands
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Milam AJ, Ghoddoussi F, Lucaj J, Narreddy S, Kumar N, Reddy V, Hakim J, Krishnan SH. Comparing the Mutual Interchangeability of ECOM, FloTrac/Vigileo, 3D-TEE, and ITD-PAC Cardiac Output Measuring Systems in Coronary Artery Bypass Grafting. J Cardiothorac Vasc Anesth 2020; 35:514-529. [PMID: 32622708 DOI: 10.1053/j.jvca.2020.03.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/18/2020] [Accepted: 03/24/2020] [Indexed: 01/19/2023]
Abstract
OBJECTIVE The aim of this study was to compare the mutual interchangeability of 4 cardiac output measuring devices by comparing their accuracy, precision, and trending ability. DESIGN A single-center prospective observational study. DESIGN Nonuniversity teaching hospital, single center. PARTICIPANTS Forty-four consecutive patients scheduled for elective, nonemergent coronary artery bypass grafting (CABG). INTERVENTIONS The cardiac output was measured for each participant using 4 methods: intermittent thermodilution via pulmonary artery catheter (ITD-PAC), Endotracheal Cardiac Output Monitor (ECOM), FloTrac/Vigileo System (FLOTRAC), and 3-dimensional transesophageal echocardiography (3D-TEE). MEASUREMENTS AND MAIN RESULTS Measurements were performed simultaneously at 5 time points: presternotomy, poststernotomy, before cardiopulmonary bypass, after cardiopulmonary bypass, and after sternal closure. A series of statistical and comparison analyses including ANOVA, Pearson correlation, Bland-Altman plots, quadrant plots, and polar plots were performed, and inherent precision for each method and percent errors for mutual interchangeability were calculated. For the 6 two-by-two comparisons of the methods, the Pearson correlation coefficients (r), the percentage errors (% error), and concordance ratios (CR) were as follows: ECOM_versus_ITD-PAC (r = 0.611, % error = 53%, CR = 75%); FLOTRAC_versus_ITD-PAC (r = 0.676, % error = 49%, CR = 77%); 3D-TEE versus ITD-PAC (r = 0.538, % error = 64%, CR = 67%); FLOTRAC_versus_ECOM (r = 0.627, % error = 51%, CR = 75%); 3D-TEE_versus ECOM (r = 0.423, % error = 70%, CR = 60%), and 3D-TEE_versus_FLOTRAC (r = 0.602, % error = 59%, CR = 61%). CONCLUSIONS Based on the recommended statistical measures of interchangeability, ECOM, FLOTRAC, and 3D-TEE are not interchangeable with each other or to the reference standard invasive ITD-PAC method in patients undergoing nonemergent cardiac bypass surgery. Despite the negative result in this study and the majority of previous studies, these less-invasive methods of CO have continued to be used in the hemodynamic management of patients. Each device has its own distinct technical features and inherent limitations; it is clear that no single device can be used universally for all patients. Therefore, different methods or devices should be chosen based on individual patient conditions, including the degree of invasiveness, measurement performance, and the ability to provide real-time, continuous CO readings.
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Affiliation(s)
- Adam J Milam
- Department of Anesthesiology, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Farhad Ghoddoussi
- Department of Anesthesiology, Wayne State University School of Medicine, Detroit, MI
| | - Jon Lucaj
- Department of Anesthesiology, Wayne State University School of Medicine, Detroit, MI; Department of Anesthesiology, St. Joseph Mercy Oakland Hospital, Pontiac, MI
| | - Spurthy Narreddy
- Department of Anesthesiology, Wayne State University School of Medicine, Detroit, MI; Department of Anesthesiology, St. Joseph Mercy Oakland Hospital, Pontiac, MI
| | - Nakul Kumar
- Department of Anesthesiology, Cleveland Clinic, Cleveland, OH
| | - Vennela Reddy
- Department of Anesthesiology, Wayne State University School of Medicine, Detroit, MI; Department of Anesthesiology, St. Joseph Mercy Oakland Hospital, Pontiac, MI
| | - Joffer Hakim
- Department of Anesthesiology, Wayne State University School of Medicine, Detroit, MI; Department of Anesthesiology, St. Joseph Mercy Oakland Hospital, Pontiac, MI
| | - Sandeep H Krishnan
- Department of Anesthesiology, Wayne State University School of Medicine, Detroit, MI; Department of Anesthesiology, St. Joseph Mercy Oakland Hospital, Pontiac, MI.
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Abstract
PURPOSE OF REVIEW Bedside cardiac output (CO) measurement is an important part of routine hemodynamic monitoring in the differential diagnosis of circulatory shock and fluid management. Different choices of CO measurement devices are available. The purpose of this review is to review the importance of CO [or stroke volume (SV)] measurement and to discuss the various methods (devices) used in determination of CO. RECENT FINDINGS CO measurement devices can be classified into two types: those use simple physical principles with minimal assumptions, and those predicting CO via mathematical modelling with a number of assumptions. Both have pros and cons, with the former being more accurate but with limited continuous monitoring capability whereas the latter less accurate but usually equipped with continuous monitoring functionality. With frequent updates in mathematical models, research data constantly become outdated in this area. Recent data suggest devices based on mathematical modelling have limited accuracies and poor precisions. SUMMARY Measurement of CO or SV is important in critically ill patients. Most devices have accuracy and reliability issues. The choice of device should depend on the purpose of measurement. For diagnostic purposes, devices based on simple physical principles, especially thermodilution and transthoracic echocardiography are more reliable due to accuracy.
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Performance of Electrical Velocimetry for Noninvasive Cardiac Output Measurements in Perioperative Patients After Subarachnoid Hemorrhage. J Neurosurg Anesthesiol 2020; 31:422-427. [PMID: 29939977 DOI: 10.1097/ana.0000000000000519] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Fluid therapy guided by cardiac output measurements is of particular importance for adequate cerebral perfusion and oxygenation in neurosurgical patients. We examined the usefulness of a noninvasive electrical velocimetry (EV) device based on the thoracic bioimpedance method for perioperative hemodynamic monitoring in patients after aneurysmal subarachnoid hemorrhage. PATIENTS AND METHODS In total, 18 patients who underwent surgical clipping or endovascular coiling for ruptured aneurysms were examined prospectively. Simultaneous cardiac index (CI) measurements obtained with EV (CIEV) and reference transpulmonary thermodilution (CITPTD) were compared. A total of 223 pairs of data were collected. RESULTS A significant correlation was found between CIEV and CITPTD (r=0.86; P<0.001). Bland and Altman analysis revealed a bias between CIEV and CITPTD of -0.06 L/min/m, with limits of agreement of ±1.14 L/min/m and a percentage error of 33%. Although the percentage error for overall data was higher than the acceptable limit of 30%, subgroup analysis during the postoperative phase showed better agreement (23% vs. 42% during the intraprocedure phase). Four-quadrant plot and polar plot analyses showed fair-to-poor trending abilities (concordance rate of 90% to 91%, angular bias of +17 degrees, radial limits of agreement between ±37 and ±40 degrees, and polar concordance rate of 72% to 75%), including the subgroup analysis. CONCLUSIONS Absolute CI values obtained from EV and TPTD are not interchangeable with TPTD for perioperative use in subarachnoid hemorrhage patients. However, considering the moderate levels of agreement with marginal trending ability during the early postoperative phase, this user-friendly device can provide an attractive monitoring option during neurocritical care.
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A Carotid Doppler Patch Accurately Tracks Stroke Volume Changes During a Preload-Modifying Maneuver in Healthy Volunteers. Crit Care Explor 2020; 2:e0072. [PMID: 32166292 PMCID: PMC7063906 DOI: 10.1097/cce.0000000000000072] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Objectives: Detecting instantaneous stroke volume change in response to altered cardiac preload is the physiologic foundation for determining preload responsiveness. Design: Proof-of-concept physiology study. Setting: Research simulation laboratory. Subjects: Twelve healthy volunteers. Interventions: A wireless continuous wave Doppler ultrasound patch was used to measure carotid velocity time integral and carotid corrected flow time during a squat maneuver. The Doppler patch measurements were compared with simultaneous stroke volume measurements obtained from a noninvasive cardiac output monitor. Measurements and Main Results: From stand to squat, stroke volume increased by 24% while carotid velocity time integral and carotid corrected flow time increased by 32% and 9%, respectively. From squat to stand, stroke volume decreased by 13%, while carotid velocity time integral and carotid corrected flow time decreased by 24% and 10%, respectively. Both changes in carotid velocity time integral and corrected flow time were closely correlated with changes in stroke volume (r2 = 0.81 and 0.62, respectively). The four-quadrant plot found a 100% concordance rate between changes in stroke volume and both changes in carotid velocity time integral and changes in corrected flow time. A change in carotid velocity time integral greater than 15% predicted a change in stroke volume greater than 10% with a sensitivity of 95% and a specificity of 92%. A change in carotid corrected flow time greater than 4% predicted a change in stroke volume greater than 10% with a sensitivity of 90% and a specificity of 92%. Conclusions: In healthy volunteers, both carotid velocity time integral and carotid corrected flow time measured by a wireless Doppler patch were useful to track changes in stroke volume induced by a preload-modifying maneuver with high sensitivity and specificity.
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Yamashita K. Pulse-wave transit time with ventilator-induced variation for the prediction of fluid responsiveness. Acute Med Surg 2020; 7:AMS2484. [PMID: 32002187 PMCID: PMC6985177 DOI: 10.1002/ams2.484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 12/18/2019] [Accepted: 12/26/2019] [Indexed: 12/05/2022] Open
Abstract
Aim Although pulse pressure variation is a good predictor of fluid responsiveness, its measurement is invasive. Therefore, a technically simple, non‐invasive method is needed for evaluating circulatory status to prevent fluid loading and optimize hemodynamic status. We focused in the pulse‐wave transit time (PWTT) defined as the time interval between electrocardiogram R wave to plethysmograph upstroke, which has been recently introduced to non‐invasively assess cardiovascular response. In the present study, we evaluated the efficacy of pulse‐wave transit time (PWTT) with ventilator‐induced variation (PWTTV) in predicting fluid responsiveness. Methods We evaluated six domestic pigs weighing 46.0 ± 3.5 kg. After anesthesia induction, electrocardiogram, femoral arterial blood pressure, plethysmograph on the tail, and carotid artery blood flow were monitored and hemorrhage was induced by withdrawing 20 mL/kg blood over 20 min; 5 mL/kg blood volume was then autotransfused over 10 min. Then PWTTV and pulse pressure variation were measured at tidal volumes of 6 and 12 mL/kg. Results Area under the receiver operating curve values for the prediction of a >10% change in carotid artery blood flow were 0.979 for pulse pressure variation and 0.993 for PWTTV at a tidal volume of 6 mL/kg and 0.979 and 0.979, respectively, at a tidal volume of 12 mL/kg (all P < 0.0001). Conclusions Measured non‐invasively, PWTTV showed similar utility to pulse pressure variation in predicting >10% changes in carotid artery blood flow induced by autotransfusion.
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Affiliation(s)
- Koichi Yamashita
- Division of Critical Care CenterKochi Red Cross HospitalKochiJapan
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40
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Bond O, Pozzebon S, Franchi F, Zama Cavicchi F, Creteur J, Vincent JL, Taccone FS, Scolletta S. Comparison of estimation of cardiac output using an uncalibrated pulse contour method and echocardiography during veno-venous extracorporeal membrane oxygenation. Perfusion 2019; 35:397-401. [DOI: 10.1177/0267659119883204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Introduction: During veno-venous extracorporeal membrane oxygenation, cardiac output monitoring is essential to assess tissue oxygen delivery. Adequate arterial oxygenation depends on the ratio between the extracorporeal pump blood flow and the cardiac output. The aim of this study was to compare estimates of cardiac output and blood flow/cardiac output ratios made using an uncalibrated pulse contour method with those made using echocardiography in patients treated with veno-venous extracorporeal membrane oxygenation. Methods: Cardiac output was estimated simultaneously using a pulse contour method (MostCareUp; Vygon, Encouen, France) and echocardiography in 17 hemodynamically stable patients treated with veno-venous extracorporeal membrane oxygenation. Comparisons were made using Bland–Altman and linear regression analysis. Results: There were significant correlations between cardiac output estimated using pulse contour method and echocardiography and between blood flow/cardiac output estimated using pulse contour method and blood flow/cardiac output estimated using echocardiography (r = 0.84, p < 0.001 and r = 0.87, p < 0.001, respectively). Bland–Altman analysis showed a good agreement (bias −0.20 ± 0.50 L/min) and a low percentage of error (25%) for the cardiac output values estimated by the two methods. The bias between the blood flow/cardiac output ratios obtained with the two methods was 5.19% ± 12.3% (percentage of error = 28.1%). Conclusions: The pulse contour method is a valuable alternative to echocardiography for the assessment of cardiac output and the blood flow/cardiac output ratio in patients treated with veno-venous extracorporeal membrane oxygenation.
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Affiliation(s)
- Ottavia Bond
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Selene Pozzebon
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Federico Franchi
- Departments of Emergency and Urgency, Medicine, Surgery and Neurosciences, Unit of Intensive Care Medicine, Siena University Hospital, Siena, Italy
| | - Federica Zama Cavicchi
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Jacques Creteur
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Jean-Louis Vincent
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Fabio Silvio Taccone
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Sabino Scolletta
- Departments of Emergency and Urgency, Medicine, Surgery and Neurosciences, Unit of Intensive Care Medicine, Siena University Hospital, Siena, Italy
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Bubenek-Turconi ŞI, Hendy A, Băilă S, Drăgan A, Chioncel O, Văleanu L, Moroșanu B, Iliescu VA. The value of a superior vena cava collapsibility index measured with a miniaturized transoesophageal monoplane continuous echocardiography probe to predict fluid responsiveness compared to stroke volume variations in open major vascular surgery: a prospective cohort study. J Clin Monit Comput 2019; 34:491-499. [PMID: 31278544 PMCID: PMC7223808 DOI: 10.1007/s10877-019-00346-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 06/27/2019] [Indexed: 11/28/2022]
Abstract
Superior vena cava collapsibility index (SVC-CI) and stroke volume variation (SVV) have been shown to predict fluid responsiveness. SVC-CI has been validated only with conventional transoesophageal echocardiography (TEE) in the SVC long axis, on the basis of SVC diameter variations, but not in the SVC short axis or by SVC area variations. SVV was not previously tested in vascular surgery patients. Forty consecutive adult patients undergoing open major vascular surgical procedures received 266 intraoperative volume loading tests (VLTs), with 500 ml of gelatine over 10 min. The hSVC-CI was measured using a miniaturized transoesophageal echocardiography probe (hTEE). The SVV and cardiac index (CI) were measured using Vigileo-FloTrac technology. VLTs were considered 'positive' (≥ 11% increase in CI) or 'negative' (< 11% increase in CI). We compared SVV and hSVC-CI measurements in the SVC short axis to predict fluid responsiveness. Areas under the receiver operating characteristic curves for hSVC-CI and SVV were not significantly different (P = 0.56), and both showed good predictivity at values of 0.92 (P < 0.001) and 0.89 (P < 0.001), respectively. The cutoff values for hSVC-CI and SVV were 37% (sensitivity 90%, specificity of 83%) and 15% (sensitivity 78%, specificity of 100%), respectively. Our study validated the value of the SVC-CI measured as area variations in the SVC short axis to predict fluid responsiveness in anesthetized patients. An hTEE probe was used to monitor and measure the hSVC-CI but conventional TEE may also offer this new dynamic parameter. In our cohort of significant preoperative hypovolemic patients undergoing major open vascular surgery, hSVC-CI and SVV cutoff values of 37% and 15%, respectively, predicted fluid responsiveness with good accuracy.
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Affiliation(s)
- Şerban-Ion Bubenek-Turconi
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bulevardul Eroii Sanitari Nr. 8, 050474, Bucharest, Romania. .,1-st Department of Cardiovascular Anaesthesiology and Intensive Care, "Prof. C. C. Iliescu" Emergency Institute for Cardiovascular Diseases, Șos. Fundeni Nr. 258, 022328, Bucharest, Romania.
| | - Adham Hendy
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bulevardul Eroii Sanitari Nr. 8, 050474, Bucharest, Romania
| | - Sorin Băilă
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bulevardul Eroii Sanitari Nr. 8, 050474, Bucharest, Romania.,Department of Cardiovascular Surgery, "Prof. C. C. Iliescu" Emergency Institute for Cardiovascular Diseases, Șos. Fundeni Nr. 258, 022328, Bucharest, Romania
| | - Anca Drăgan
- 1-st Department of Cardiovascular Anaesthesiology and Intensive Care, "Prof. C. C. Iliescu" Emergency Institute for Cardiovascular Diseases, Șos. Fundeni Nr. 258, 022328, Bucharest, Romania
| | - Ovidiu Chioncel
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bulevardul Eroii Sanitari Nr. 8, 050474, Bucharest, Romania.,1-st Department of Cardiology, "Prof. C. C. Iliescu" Emergency Institute for Cardiovascular Diseases, Șos. Fundeni Nr. 258, 022328, Bucharest, Romania
| | - Liana Văleanu
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bulevardul Eroii Sanitari Nr. 8, 050474, Bucharest, Romania.,1-st Department of Cardiovascular Anaesthesiology and Intensive Care, "Prof. C. C. Iliescu" Emergency Institute for Cardiovascular Diseases, Șos. Fundeni Nr. 258, 022328, Bucharest, Romania
| | - Bianca Moroșanu
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bulevardul Eroii Sanitari Nr. 8, 050474, Bucharest, Romania.,1-st Department of Cardiovascular Anaesthesiology and Intensive Care, "Prof. C. C. Iliescu" Emergency Institute for Cardiovascular Diseases, Șos. Fundeni Nr. 258, 022328, Bucharest, Romania
| | - Vlad-Anton Iliescu
- University of Medicine and Pharmacy "Carol Davila" Bucharest, Bulevardul Eroii Sanitari Nr. 8, 050474, Bucharest, Romania.,Department of Cardiovascular Surgery, "Prof. C. C. Iliescu" Emergency Institute for Cardiovascular Diseases, Șos. Fundeni Nr. 258, 022328, Bucharest, Romania
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42
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Hao GW, Liu Y, Ma GG, Hou JY, Zhu DM, Liu L, Zhang Y, Liu H, Zhuang YM, Luo Z, Tu GW, Yang XM, Chen HY. Reliability of three-dimensional color flow Doppler and two-dimensional pulse wave Doppler transthoracic echocardiography for estimating cardiac output after cardiac surgery. Cardiovasc Ultrasound 2019; 17:5. [PMID: 30944001 PMCID: PMC6448273 DOI: 10.1186/s12947-019-0155-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 03/01/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Three-dimensional color flow Doppler (3DCF) is a new convenient technique for cardiac output (CO) measurement. However, to date, no one has evaluated the accuracy of 3DCF echocardiography for CO measurement after cardiac surgery. Therefore, this single-center, prospective study was designed to evaluate the reliability of three-dimensional color flow and two-dimensional pulse wave Doppler (2D-PWD) transthoracic echocardiography for estimating cardiac output after cardiac surgery. METHODS Post-cardiac surgical patients with a good acoustic window and a low dose or no dose of vasoactive drugs (norepinephrine < 0.05 μg/kg/min) were enrolled for CO estimation. Three different methods (third generation FloTrac/Vigileo™ [FT/V] system as the reference method, 3DCF, and 2D-PWD) were used to estimate CO before and after interventions (baseline, after volume expansion, and after a dobutamine test). RESULTS A total of 20 patients were enrolled in this study, and 59 pairs of CO measurements were collected (one pair was not included because of increasing drainage after the dobutamine test). Pearson's coefficients were 0.260 between the CO-FT/V and CO-PWD measurements and 0.729 between the CO-FT/V and CO-3DCF measurements. Bland-Altman analysis showed the bias between the absolute values of CO-FT/V and CO-PWD measurements was - 0.6 L/min with limits of agreement between - 3.3 L/min and 2.2 L/min, with a percentage error (PE) of 61.3%. The bias between CO-FT/V and CO-3DCF was - 0.14 L/min with limits of agreement between - 1.42 L /min and 1.14 L/min, with a PE of 29.9%. Four-quadrant plot analysis showed the concordance rate between ΔCO-PWD and ΔCO-3FT/V was 93.3%. CONCLUSIONS In a comparison with the FT/V system, 3DCF transthoracic echocardiography could accurately estimate CO in post-cardiac surgical patients, and the two methods could be considered interchangeable. Although 2D-PWD echocardiography was not as accurate as the 3D technique, its ability to track directional changes was reliable.
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Affiliation(s)
- Guang-Wei Hao
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Yang Liu
- Department of Echocardiography, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Guo-Guang Ma
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Jun-Yi Hou
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Du-Ming Zhu
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Lan Liu
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Ying Zhang
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Hua Liu
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Ya-Min Zhuang
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Zhe Luo
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Guo-Wei Tu
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China
| | - Xiao-Mei Yang
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China.
| | - Hai-Yan Chen
- Department of Echocardiography, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui District, Shanghai, 200032, People's Republic of China.
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Coote JM, Alles EJ, Noimark S, Mosse CA, Little CD, Loder CD, David AL, Rakhit RD, Finlay MC, Desjardins AE. Dynamic physiological temperature and pressure sensing with phase-resolved low-coherence interferometry. OPTICS EXPRESS 2019; 27:5641-5654. [PMID: 30876162 PMCID: PMC6410922 DOI: 10.1364/oe.27.005641] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We report the development and characterisation of highly miniaturised fibre-optic sensors for simultaneous pressure and temperature measurement, and a compact interrogation system with a high sampling rate. The sensors, which have a maximum diameter of 250 µm, are based on multiple low-finesse optical cavities formed from polydimethylsiloxane (PDMS), positioned at the distal ends of optical fibres, and interrogated using phase-resolved low-coherence interferometry. At acquisition rates of 250 Hz, temperature and pressure changes of 0.0021 °C and 0.22 mmHg are detectable. An in vivo experiment demonstrated that the sensors had sufficient speed and sensitivity for monitoring dynamic physiological pressure waveforms. These sensors are ideally suited to various applications in minimally invasive surgery, where diminutive lateral dimensions, high sensitivity and low manufacturing complexities are particularly valuable.
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Affiliation(s)
- J. M. Coote
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
| | - E. J. Alles
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
| | - S. Noimark
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
- Materials Chemistry Research Centre, Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - C. A. Mosse
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
| | - C. D. Little
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
- The Royal Free Hospital, Pond Street, London NW3 2QG, United Kingdom
| | - C. D. Loder
- The Royal Free Hospital, Pond Street, London NW3 2QG, United Kingdom
| | - A. L. David
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
- Institute for Women’s Health, University College London, 86-96 Chenies Mews, London WC1E 6HX, United Kingdom
| | - R. D. Rakhit
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
- The Royal Free Hospital, Pond Street, London NW3 2QG, United Kingdom
| | - M. C. Finlay
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
- Barts Heart Centre, St Bartholomew’s Hospital and Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, United Kingdom
| | - A. E. Desjardins
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, Charles Bell House, 43-45 Foley Street, London W1W 7TS, United Kingdom
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Tronstad C, Høgetveit JO, Elvebakk O, Kalvøy H. Age-related Differences in the Morphology of the Impedance Cardiography Signal. JOURNAL OF ELECTRICAL BIOIMPEDANCE 2019; 10:139-145. [PMID: 33584895 PMCID: PMC7851975 DOI: 10.2478/joeb-2019-0020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Indexed: 06/12/2023]
Abstract
Impedance cardiography (ICG) is a non-invasive method of hemodynamic measurement, mostly known for estimation of stroke volume and cardiac output based on characteristic features of the signal. Compared with electrocardiography, the knowledge on the morphology of the ICG signal is scarce, especially with respect to age-dependent changes in ICG waveforms. Based on recordings from ten younger (20-29 years) and ten older (60-79) healthy human subjects after three different levels of physical activity, the typical interbeat ICG waveforms were derived based on ensemble averages. Comparison of these waveforms between the age groups indicates the following differences: a later initial upward deflection for the younger group, an additional hump in the waveform from many older subjects not presented in the younger group, and a more pronounced second wave in the younger group. The explanation for these differences is not clear, but may be related to arterial stiffness. Further studies are suggested to determine whether these morphological differences have clinical value.
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Affiliation(s)
- Christian Tronstad
- Department of Clinical and Biomedical Engineering, Oslo University Hospital, Oslo, Norway
| | - Jan Olav Høgetveit
- Department of Clinical and Biomedical Engineering, Oslo University Hospital, Oslo, Norway
- Department of Physics, University of Oslo, Oslo. Norway
| | - Ole Elvebakk
- Department of Clinical and Biomedical Engineering, Oslo University Hospital, Oslo, Norway
| | - Håvard Kalvøy
- Department of Clinical and Biomedical Engineering, Oslo University Hospital, Oslo, Norway
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Maeda T, Hamaguchi E, Kubo N, Shimokawa A, Kanazawa H, Ohnishi Y. The accuracy and trending ability of cardiac index measured by the fourth-generation FloTrac/Vigileo system™ and the Fick method in cardiac surgery patients. J Clin Monit Comput 2018; 33:767-776. [DOI: 10.1007/s10877-018-0217-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 11/01/2018] [Indexed: 12/25/2022]
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46
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Yin K, Ding J, Wu Y, Peng M. Goal-directed fluid therapy based on noninvasive cardiac output monitor reduces postoperative complications in elderly patients after gastrointestinal surgery: A randomized controlled trial. Pak J Med Sci 2018; 34:1320-1325. [PMID: 30559778 PMCID: PMC6290223 DOI: 10.12669/pjms.346.15854] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Objective: Goal-directed fluid therapy (GDFT) was associated with improved outcomes after surgery. Noninvasive Cardiac Output Monitoring (NICOM) has proved to be a good choice for guiding GDFT. This study evaluated the effect of GDFT based on NICOM on prognosis in elderly patients undergoing resection of gastrointestinal tumor. Methods: Fifty patients scheduled for elective laparoscopic radical resection for stomach, colon or rectal cancer in Yongchuan Hospital of Chongqing Medical University between November 2014 and December 2015 were included and randomly divided into two groups: conventional fluid therapy (group C, n=25) and goal-directed fluid therapy (group G, n=25). The primary outcome was moderate or severe postoperative complications within 30 days. Results: Finally, 45 patients successfully completed the study (group G, n=22; group C, n=23). There were no difference of the duration of surgery, the requirement of vasoactive agents and the bleeding volume between two groups (P>0.05). Total fluids infused were 2956±629 ml (group C) and 2259±454 ml (group G) (P<0.05), while the requirement of colloid was increased in group G (1103±285ml vs 855±226ml) (P<0.05). The MAP and the mean CI were higher in group G (P<0.05). Compared with group C, the time when the patients passed the flatus and the length of hospital stay after operation were shortened in group G (12.6±2.4day vs17.2±2.6day), the incidence of postoperative complications were significantly lower in group G (P<0.05). Conclusions: Goal-directed fluid therapy based on NICOM was significantly associated with improvement of prognosis in elderly patients undergoing resection of gastrointestinal tumor which reduced postoperative complications.
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Affiliation(s)
- Kaiyu Yin
- Kaiyu Yin, Department of Anesthesiology, Yongchuan Hospital of Chongqing Medical University, Chongqing, 402160, China
| | - Jiahui Ding
- Jiahui Ding, Department of Anesthesiology, Yongchuan Hospital of Chongqing Medical University, Chongqing, 402160, China
| | - You Wu
- You Wu, Department of Anesthesiology, Yongchuan Hospital of Chongqing Medical University, Chongqing, 402160, China
| | - Mingqing Peng
- Mingqing Peng, Department of Anesthesiology, Yongchuan Hospital of Chongqing Medical University, Chongqing, 402160, China
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Zayat R, Drosos V, Schnoering H, Lee JY, Bleilevens C, Musetti G, Jansen-Park SH, Kang H, Menon AK, Schmitz-Rode T, Autschbach R, Hatam N, Moza A. Radial Artery Tonometry to Monitor Blood Pressure and Hemodynamics in Ambulatory Left Ventricular Assist Device Patients in Comparison With Doppler Ultrasound and Transthoracic Echocardiography: A Pilot Study. Artif Organs 2018; 43:242-253. [PMID: 30040134 DOI: 10.1111/aor.13335] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 07/14/2018] [Accepted: 07/18/2018] [Indexed: 01/08/2023]
Abstract
Noninvasive measurements of blood pressure (BP) and cardiac output (CO) are crucial in the follow-up of continuous-flow left ventricular assist device (CF-LVAD) patients. For our pilot study, we sought to compare BP measurements between a tonometry blood pressure pulse analyzer (BPPA) (DMP-Life, DAEYOMEDI Co., Ltd., Gyeonggi-do, South Korea) and Doppler ultrasound in CF-LVAD patients, as well as to compare the BPPA estimated CO to LVAD calculated blood flow and to the patient's intrinsic CO estimated with transthoracic echocardiography (TTE). Ambulatory CF-LVAD patients (6 HeartMate, 26 HeartMate II), were included. According to TTE findings, patients were then subdivided in two groups: patients with an opening aortic valve (OAV) [n = 21] and those with an intermittent opening aortic valve (IOAV) [n = 11]. We found a very good correlation of systolic BP (SBP) measurements between the two methods, BPPA and Doppler ultrasound (r = 0.87, P < 0.0001). Bland-Altman plots for SBP revealed a low bias of -4.6 mm Hg and SD of ±4.7 mm Hg. In CF-LVAD patients with IOAV, the BPPA-CO had a good correlation with the LVAD-flow (r = 0.78, P < 0.0001), but in OAV patients, there was no correlation. After adding the patient's intrinsic CO, estimated from TTE in patients with OAV to the LVAD-flow, we found a very good correlation between the BPPA-CO and LVAD-flow + TTE-CO (r = 0.81, P = 0.002). Our study demonstrated that compared with the standard clinical method, Doppler ultrasound, the BPPA measured BP noninvasively with good accuracy and precision of agreement. In addition, tonometry BPPA provided further valuable information regarding the CF-LVAD patient's intrinsic CO.
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Affiliation(s)
- Rashad Zayat
- Department of Thoracic and Cardiovascular Surgery, RWTH University Hospital, Aachen, Germany
| | - Vasileios Drosos
- Department of Thoracic and Cardiovascular Surgery, RWTH University Hospital, Aachen, Germany
| | - Heike Schnoering
- Department of Thoracic and Cardiovascular Surgery, RWTH University Hospital, Aachen, Germany
| | - Ju-Yeon Lee
- Department of Oriental Biomedical Engineering, Sang-Ji University, Won-Ju, South Korea
| | - Christian Bleilevens
- Department of Anesthesiology, University Hospital RWTH Aachen, Helmholtz Institute, RWTH Aachen University, Aachen, Germany
| | - Giulia Musetti
- Department of Thoracic and Cardiovascular Surgery, RWTH University Hospital, Aachen, Germany
| | - So-Hyun Jansen-Park
- Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany
| | | | - Ares K Menon
- Department of Thoracic and Cardiovascular Surgery, RWTH University Hospital, Aachen, Germany
| | - Thomas Schmitz-Rode
- Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany
| | - Rüdiger Autschbach
- Department of Thoracic and Cardiovascular Surgery, RWTH University Hospital, Aachen, Germany
| | - Nima Hatam
- Department of Thoracic and Cardiovascular Surgery, RWTH University Hospital, Aachen, Germany
| | - Ajay Moza
- Department of Thoracic and Cardiovascular Surgery, RWTH University Hospital, Aachen, Germany
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Agreement Between Transesophageal Echocardiography and Thermodilution-Based Cardiac Output. Anesth Analg 2018; 127:329-330. [DOI: 10.1213/ane.0000000000003322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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49
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Optimizing target control of the vessel rich group with volatile anesthetics. J Clin Monit Comput 2018; 33:445-454. [PMID: 29931573 DOI: 10.1007/s10877-018-0169-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 06/07/2018] [Indexed: 10/28/2022]
Abstract
The ability to monitor the inspired and expired concentrations of volatile anesthetic gases in real time makes these drugs implicitly targetable. However, the end-tidal concentration only represents the concentration within the brain and the vessel rich group (VRG) at steady state, and very poorly approximates the VRG concentration during common dynamic situations such as initial uptake and emergence. How should the vaporization of anesthetic gases be controlled in order to optimally target VRG concentration in clinical practice? Using a generally accepted pharmacokinetic model of uptake and redistribution, a transfer function from the vaporizer setting to the VRG is established and transformed to the time domain. Targeted actuation of the vaporizer in a time-optimal manner is produced by a variable structure, sliding mode controller. Direct mathematical application of the controller produces rapid cycling at the limits of the vaporizer, further prolonged by low fresh gas flows. This phenomenon, known as "chattering", is unsuitable for operating real equipment. Using a simple and clinically intuitive modification to the targeting algorithm, a variable low-pass boundary layer is applied to the actuation, smoothing discontinuities in the control law and practically eliminating chatter without prolonging the time taken to reach the VRG target concentration by any clinically significant degree. A model is derived for optimum VRG-targeted control of anesthetic vaporizers. An alternate and further application is described, in which deliberate perturbation of the vaporization permits non-invasive estimation of parameters such as cardiac output that are otherwise difficult to measure intra-operatively.
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50
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Minimally invasive cardiac output technologies in the ICU: putting it all together. Curr Opin Crit Care 2018; 23:302-309. [PMID: 28538248 DOI: 10.1097/mcc.0000000000000417] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
PURPOSE OF REVIEW Haemodynamic monitoring is a cornerstone in the diagnosis and evaluation of treatment in critically ill patients in circulatory distress. The interest in using minimally invasive cardiac output monitors is growing. The purpose of this review is to discuss the currently available devices to provide an overview of their validation studies in order to answer the question whether these devices are ready for implementation in clinical practice. RECENT FINDINGS Current evidence shows that minimally invasive cardiac output monitoring devices are not yet interchangeable with (trans)pulmonary thermodilution in measuring cardiac output. However, validation studies are generally single centre, are based on small sample sizes in heterogeneous groups, and differ in the statistical methods used. SUMMARY Minimally and noninvasive monitoring devices may not be sufficiently accurate to replace (trans)pulmonary thermodilution in estimating cardiac output. The current paradigm shift to explore trending ability rather than investigating agreement of absolute values alone is to be applauded. Future research should focus on the effectiveness of these devices in the context of (functional) haemodynamic monitoring before adoption into clinical practice can be recommended.
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