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Bertacchi M, Wendel-Garcia PD, Hana A, Ince C, Maggiorini M, Hilty MP. Nitroglycerin challenge identifies microcirculatory target for improved resuscitation in patients with circulatory shock. Intensive Care Med Exp 2024; 12:76. [PMID: 39222259 PMCID: PMC11369126 DOI: 10.1186/s40635-024-00662-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 08/21/2024] [Indexed: 09/04/2024] Open
Abstract
BACKGROUND Circulatory shock and multi-organ failure remain major contributors to morbidity and mortality in critically ill patients and are associated with insufficient oxygen availability in the tissue. Intrinsic mechanisms to improve tissue perfusion, such as up-regulation of functional capillary density (FCD) and red blood cell velocity (RBCv), have been identified as maneuvers to improve oxygen extraction by the tissues; however, their role in circulatory shock and potential use as resuscitation targets remains unknown. To fill this gap, we examined the baseline and maximum recruitable FCD and RBCv in response to a topical nitroglycerin stimulus (FCDNG, RBCvNG) in patients with and without circulatory shock to test whether this may be a method to identify the presence and magnitude of a microcirculatory reserve capacity important for identifying a resuscitation target. METHODS Sublingual handheld vital microscopy was performed after initial resuscitation in mechanically ventilated patients consecutively admitted to a tertiary medical ICU. FCD and RBCv were quantified using an automated computer vision algorithm (MicroTools). Patients with circulatory shock were retrospectively identified via standardized hemodynamic and clinical criteria and compared to patients without circulatory shock. RESULTS 54 patients (57 ± 14y, BMI 26.3 ± 4.9 kg/m2, SAPS 56 ± 19, 65% male) were included, 13 of whom presented with circulatory shock. Both groups had similar cardiac index, mean arterial pressure, RBCv, and RBCvNG. Heart rate (p < 0.001), central venous pressure (p = 0.02), lactate (p < 0.001), capillary refill time (p < 0.01), and Mottling score (p < 0.001) were higher in circulatory shock after initial resuscitation, while FCD and FCDNG were 10% lower (16.9 ± 4.2 and 18.9 ± 3.2, p < 0.01; 19.3 ± 3.1 and 21.3 ± 2.9, p = 0.03). Nitroglycerin response was similar in both groups, and circulatory shock patients reached FCDNG similar to baseline FCD found in patients without shock. CONCLUSION Critically ill patients suffering from circulatory shock were found to present with a lower sublingual FCD. The preserved nitroglycerin response suggests a dysfunction of intrinsic regulation mechanisms to increase the microcirculatory oxygen extraction capacity associated with circulatory shock and identifies a potential resuscitation target. These differences in microcirculatory hemodynamic function between patients with and without circulatory shock were not reflected in blood pressure or cardiac index.
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Affiliation(s)
- Massimiliano Bertacchi
- Institute of Intensive Care Medicine, University Hospital of Zurich, Zurich, Switzerland
| | - Pedro D Wendel-Garcia
- Institute of Intensive Care Medicine, University Hospital of Zurich, Zurich, Switzerland
| | - Anisa Hana
- Institute of Intensive Care Medicine, University Hospital of Zurich, Zurich, Switzerland
| | - Can Ince
- Laboratory of Translational Intensive Care, Department of Intensive Care, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Marco Maggiorini
- Institute of Intensive Care Medicine, University Hospital of Zurich, Zurich, Switzerland
| | - Matthias P Hilty
- Institute of Intensive Care Medicine, University Hospital of Zurich, Zurich, Switzerland.
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2
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De Cuyper H, Poelaert J. Microcirculatory Alterations in Cardiac Surgery: A Comprehensive Guide. J Cardiothorac Vasc Anesth 2024; 38:829-838. [PMID: 38195271 DOI: 10.1053/j.jvca.2023.11.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 11/09/2023] [Accepted: 11/29/2023] [Indexed: 01/11/2024]
Abstract
Microcirculation is essential for cellular life and its functions. It comprises a complex network of capillaries, arterioles, and venules, which distributes oxygenated blood across and within organs based on regional metabolic demands. Because previous research indicated that organ function is linked to microcirculatory function, it is crucial to maintain sufficient and effective microcirculatory function during major surgery. Impaired microcirculation can lead to inadequate tissue perfusion, potentially resulting in perioperative complications and an unfavorable outcome. Indeed, changes in microcirculation in cardiovascular disease and cardiac surgery have a direct correlation with prolonged stays in the postoperative intensive care unit and high mortality rates within 30 days. Additionally, cardiopulmonary bypass, a regularly employed method in cardiac surgery, has been proven to induce microcirculatory malfunction and, thus, lead to postoperative multiple organ dysfunction. As global hemodynamic parameters can remain stable or improve, whereas microcirculation is still compromised, tracking microcirculatory variables could lead to the development of targeted microcirculatory treatment within hemodynamic management. Therefore, it is necessary to enhance the use of microcirculatory monitoring in the medical domain to assist physicians in the therapeutic management of patients undergoing cardiac surgery. This potentially can lead to better hemodynamic management and outcomes. This review article concentrates on the use of handheld video microscopes for real-time microcirculatory assessment of cardiac surgery patients in the immediate and early postoperative period. Emphasis is placed on integrating microcirculatory monitoring with conventional hemodynamic monitoring in the therapeutic management of patients undergoing cardiac surgery.
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Affiliation(s)
- Hélène De Cuyper
- Department Anesthesiology and Perioperative Medicine, UZ Brussels, Brussels, Belgium; Free University Brussels VUB, Brussels, Belgium.
| | - Jan Poelaert
- Free University Brussels VUB, Brussels, Belgium; Department Anesthesiology, ICU and Chronic Pain Therapy, Maria Middelares, Ghent, Belgium
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3
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Flick M, Hilty MP, Duranteau J, Saugel B. The microcirculation in perioperative medicine: a narrative review. Br J Anaesth 2024; 132:25-34. [PMID: 38030549 DOI: 10.1016/j.bja.2023.10.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 09/25/2023] [Accepted: 10/10/2023] [Indexed: 12/01/2023] Open
Abstract
The microcirculation describes the network of the smallest vessels in our cardiovascular system. On a microcirculatory level, oxygen delivery is determined by the flow of oxygen-carrying red blood cells in a given single capillary (capillary red blood cell flow) and the density of the capillary network in a given tissue volume (capillary vessel density). Handheld vital videomicroscopy enables visualisation of the capillary bed on the surface of organs and tissues but currently is only used for research. Measurements are generally possible on all organ surfaces but are most often performed in the sublingual area. In patients presenting for elective surgery, the sublingual microcirculation is usually intact and functional. Induction of general anaesthesia slightly decreases capillary red blood cell flow and increases capillary vessel density. During elective, even major, noncardiac surgery, the sublingual microcirculation is preserved and remains functional, presumably because elective noncardiac surgery is scheduled trauma and haemodynamic alterations are immediately treated by anaesthesiologists, usually restoring the macrocirculation before the microcirculation is substantially impaired. Additionally, surgery is regional trauma and thus likely causes regional, rather than systemic, impairment of the microcirculation. Whether or not the sublingual microcirculation is impaired after noncardiac surgery remains a subject of ongoing research. Similarly, it remains unclear if cardiac surgery, especially with cardiopulmonary bypass, impairs the sublingual microcirculation. The effects of therapeutic interventions specifically targeting the microcirculation remain to be elucidated and tested. Future research should focus on further improving microcirculation monitoring methods and investigating how regional microcirculation monitoring can inform clinical decision-making and treatment.
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Affiliation(s)
- Moritz Flick
- Department of Anesthesiology, Center of Anesthesiology and Intensive Care Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Matthias P Hilty
- Institute of Intensive Care Medicine, University Hospital of Zurich, Zurich, Switzerland
| | - Jacques Duranteau
- Department of Anesthesiology and Intensive Care, Paris-Saclay University, Bicêtre Hospital, Assistance Publique Hôpitaux de Paris (AP-HP), Le Kremlin-Bicêtre, France
| | - Bernd Saugel
- Department of Anesthesiology, Center of Anesthesiology and Intensive Care Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Outcomes Research Consortium, Cleveland, OH, USA
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4
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Beukers AM, Hugo JDV, Haumann RG, Boltje JWT, Ie ELK, Loer SA, Bulte CSE, Vonk A. Changes in colloid oncotic pressure during cardiac surgery with different prime fluid strategies. Perfusion 2023:2676591231193626. [PMID: 37553122 DOI: 10.1177/02676591231193626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
OBJECTIVE In cardiac surgery, colloid oncotic pressure (COP) is affected by haemodilution that results from composition and volume of prime fluid of cardiopulmonary bypass (CPB). However, the extent to which different priming strategies alter COP is largely unknown. Therefore, we investigated the effect of different priming strategies on COP in on-pump cardiac surgery. METHODS Patients (n = 60) were divided into 3 groups (n = 20 each), based on the center in which they were operated and the specific prime fluid strategy used in that center during the inclusion period. CPB prime fluids were either gelofusine-, albumin-, or crystalloid based, the latter two with or without retrograde autologous priming. RESULTS In all groups, COP was lowest after weaning from CPB and one hour after CPB. Between groups, COP was lowest with gelofusine prime fluid (16.4, 16.8 mmHg, respectively) compared with crystalloids (MD: -1.9; 95% CI:-3.6, -0.2; p = .02 and MD: -2.4, 95% CI: -4.2, -0.7; p = .002) and albumin (MD: -1.8, 95% CI: -3.5, -0.50; p = .041 and MD: -2.4, 95% CI: -4.1, -0.7; p = .002). In all groups, the decrease in COP one hour after bypass compared to baseline correlated positively with fluid balance at the end of surgery (p < .001). CONCLUSIONS COP significantly decrease during CPB surgery with the largest decrease in COP at the end of surgery, while at the same time fluid balance increases. We suggest that prime fluid strategy should be carefully selected when maintenance of COP during cardiac surgery is desirable.
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Affiliation(s)
- Anne Maria Beukers
- Department of Anaesthesiology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | - Juan de Villiers Hugo
- Department of Cardiothoracic Surgery, LUMC, Leiden University, Leiden, The Netherlands
| | | | - Jan Willem Taco Boltje
- Department of Cardiothoracic Surgery, Amsterdam UMC location University of Amsterdam, Amsterdam, The Netherlands
| | - Evy Loan Khiam Ie
- Department of Anaesthesiology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Stephan Alexander Loer
- Department of Anaesthesiology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Carolien Suzanna Enna Bulte
- Department of Anaesthesiology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | - Alexander Vonk
- Department of Cardiothoracic Surgery, Amsterdam UMC location University of Amsterdam, Amsterdam, The Netherlands
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Jávor P, Donka T, Horváth T, Sándor L, Török L, Szabó A, Hartmann P. Impairment of Mesenteric Perfusion as a Marker of Major Bleeding in Trauma Patients. J Clin Med 2023; 12:jcm12103571. [PMID: 37240677 DOI: 10.3390/jcm12103571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/17/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
The majority of potentially preventable mortality in trauma patients is related to bleeding; therefore, early recognition and effective treatment of hemorrhagic shock impose a cardinal challenge for trauma teams worldwide. The reduction in mesenteric perfusion (MP) is among the first compensatory responses to blood loss; however, there is no adequate tool for splanchnic hemodynamic monitoring in emergency patient care. In this narrative review, (i) methods based on flowmetry, CT imaging, video microscopy (VM), measurement of laboratory markers, spectroscopy, and tissue capnometry were critically analyzed with respect to their accessibility, and applicability, sensitivity, and specificity. (ii) Then, we demonstrated that derangement of MP is a promising diagnostic indicator of blood loss. (iii) Finally, we discussed a new diagnostic method for the evaluation of hemorrhage based on exhaled methane (CH4) measurement. Conclusions: Monitoring the MP is a feasible option for the evaluation of blood loss. There are a wide range of experimentally used methodologies; however, due to their practical limitations, only a fraction of them could be integrated into routine emergency trauma care. According to our comprehensive review, breath analysis, including exhaled CH4 measurement, would provide the possibility for continuous, non-invasive monitoring of blood loss.
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Affiliation(s)
- Péter Jávor
- Department of Traumatology, University of Szeged, H-6725 Szeged, Hungary
| | - Tibor Donka
- Department of Traumatology, University of Szeged, H-6725 Szeged, Hungary
| | - Tamara Horváth
- Institute of Surgical Research, University of Szeged, H-6724 Szeged, Hungary
| | - Lilla Sándor
- Department of Traumatology, University of Szeged, H-6725 Szeged, Hungary
| | - László Török
- Department of Traumatology, University of Szeged, H-6725 Szeged, Hungary
- Department of Sports Medicine, University of Szeged, H-6725 Szeged, Hungary
| | - Andrea Szabó
- Institute of Surgical Research, University of Szeged, H-6724 Szeged, Hungary
| | - Petra Hartmann
- Department of Traumatology, University of Szeged, H-6725 Szeged, Hungary
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De Backer D. Novelties in the evaluation of microcirculation in septic shock. JOURNAL OF INTENSIVE MEDICINE 2023; 3:124-130. [PMID: 37188120 PMCID: PMC10175708 DOI: 10.1016/j.jointm.2022.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 08/25/2022] [Accepted: 09/01/2022] [Indexed: 05/17/2023]
Abstract
Microvascular alterations were first described in critically ill patients about 20 years ago. These alterations are characterized by a decrease in vascular density and presence of non-perfused capillaries close to well-perfused vessels. In addition, heterogeneity in microvascular perfusion is a key finding in sepsis. In this narrative review, we report our actual understanding of microvascular alterations, their role in the development of organ dysfunction, and the implications for outcome. Herein, we discuss the state of the potential therapeutic interventions and the potential impact of novel therapies. We also discuss how recent technologic development may affect the evaluation of microvascular perfusion.
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Elia J, Diwan M, Deshpande R, Brainard JC, Karamchandani K. Perioperative Fluid Management and Volume Assessment. Anesthesiol Clin 2023; 41:191-209. [PMID: 36871999 DOI: 10.1016/j.anclin.2022.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
Fluid therapy is an integral component of perioperative care and helps maintain or restore effective circulating blood volume. The principal goal of fluid management is to optimize cardiac preload, maximize stroke volume, and maintain adequate organ perfusion. Accurate assessment of volume status and volume responsiveness is necessary for appropriate and judicious utilization of fluid therapy. To accomplish this, static and dynamic indicators of fluid responsiveness have been widely studied. This review discusses the overarching goals of perioperative fluid management, reviews the physiology and parameters used to assess fluid responsiveness, and provides evidence-based recommendations on intraoperative fluid management.
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Affiliation(s)
- Jennifer Elia
- Department of Anesthesiology, University of California, Irvine School of Medicine, 101 The City Drive South, Building 53-225, Orange, CA 92868, USA.
| | - Murtaza Diwan
- Department of Anesthesiology, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Ranjit Deshpande
- Department of Anesthesiology, Yale School of Medicine, 333Cedars Street, TMP 3, New Haven, CT 06510, USA
| | - Jason C Brainard
- Department of Anesthesiology, University of Colorado, University of Colorado Hospital, 12401 East 17th Avenue, Mail Stop B113, Aurora, CO 80045, USA
| | - Kunal Karamchandani
- Department of Anesthesiology and Pain Management, University of Texas, Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
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8
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Jávor P, Rárosi F, Horváth T, Török L, Varga E, Hartmann P. Detection of exhaled methane levels for monitoring trauma-related haemorrhage following blunt trauma: study protocol for a prospective observational study. BMJ Open 2022; 12:e057872. [PMID: 35793921 PMCID: PMC9260765 DOI: 10.1136/bmjopen-2021-057872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Early recognition and effective treatment of internal bleeding impose a cardinal challenge for trauma teams. The reduction of the superior mesenteric artery (SMA) blood flow is among the first compensatory responses to blood loss, thus being a promising candidate as a diagnostic tool for occult haemorrhage. Unfortunately, methods for monitoring the SMA flow have not been elaborated to date. Nevertheless, animal experiments suggest that exhaled methane (CH4) levels correspond to the SMA perfusion. We hypothesise that real-time detection of CH4 concentrations in the exhaled air is an applicable technique for the early recognition of haemorrhage in severely injured patients. We also hypothesise that exhaled CH4 levels reflect the volume of blood loss more accurately than conventional markers of blood loss and shock such as shock index, haemoglobin, base deficit, lactate, end-tidal carbon dioxide and sublingual microcirculatory indices. METHODS AND ANALYSIS One hundred and eleven severely injured (Injury Severity Score ≥16), intubated, bleeding patients sustaining blunt trauma will be included in this prospective observational study. Blood loss will be detected with CT and estimated with CT-linked radiologic software. Exhaled CH4 concentrations will be monitored by attaching a near-infrared laser technique-based photoacoustic spectroscopy apparatus to the exhalation outlet of the ventilator on patient arrival. The primary outcome is the volume of blood loss. Need for massive transfusion and 24-hour mortality will constitute secondary outcomes. The relation of exhaled CH4 to study outcomes and its performance in predicting blood loss in comparison with conventional shock markers and microcirculatory indices will be tested. ETHICS AND DISSEMINATION Our protocol (ID: 5400/2021-SZTE) has been registered on ClinicalTrials.gov (NCT04987411) and complies with the Declaration of Helsinki and has been approved by the medical ethics committee at the University of Szeged (Ref.nr.:121/2021-SZTE RKEB). It is in data collection phase, theresults will be shared with the scientific community through publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER NCT04987411; ClinicalTrials.gov, registered on 27 July 2021.
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Affiliation(s)
- Péter Jávor
- Department of Traumatology, University of Szeged, Szeged, Hungary
| | - Ferenc Rárosi
- Department of Medical Physics and Informatics, University of Szeged, Szeged, Hungary
| | - Tamara Horváth
- Institute of Surgical Research, University of Szeged, Szeged, Hungary
| | - László Török
- Department of Traumatology, University of Szeged, Szeged, Hungary
- Department of Sports Medicine, University of Szeged, Szeged, Hungary
| | - Endre Varga
- Department of Traumatology, University of Szeged, Szeged, Hungary
| | - Petra Hartmann
- Department of Traumatology, University of Szeged, Szeged, Hungary
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Mallat J, Rahman N, Hamed F, Hernandez G, Fischer MO. Pathophysiology, mechanisms, and managements of tissue hypoxia. Anaesth Crit Care Pain Med 2022; 41:101087. [PMID: 35462083 DOI: 10.1016/j.accpm.2022.101087] [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: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 11/01/2022]
Abstract
Oxygen is needed to generate aerobic adenosine triphosphate and energy that is required to support vital cellular functions. Oxygen delivery (DO2) to the tissues is determined by convective and diffusive processes. The ability of the body to adjust oxygen extraction (ERO2) in response to changes in DO2 is crucial to maintain constant tissue oxygen consumption (VO2). The capability to increase ERO2 is the result of the regulation of the circulation and the effects of the simultaneous activation of both central and local factors. The endothelium plays a crucial role in matching tissue oxygen supply to demand in situations of acute drop in tissue oxygenation. Tissue oxygenation is adequate when tissue oxygen demand is met. When DO2 is severely compromised, a critical DO2 value is reached below which VO2 falls and becomes dependent on DO2, resulting in tissue hypoxia. The different mechanisms of tissue hypoxia are circulatory, anaemic, and hypoxic, characterised by a diminished DO2 but preserved capacity of increasing ERO2. Cytopathic hypoxia is another mechanism of tissue hypoxia that is due to impairment in mitochondrial respiration that can be observed in septic conditions with normal overall DO2. Sepsis induces microcirculatory alterations with decreased functional capillary density, increased number of stopped-flow capillaries, and marked heterogeneity between the areas with large intercapillary distance, resulting in impairment of the tissue to extract oxygen and to satisfy the increased tissue oxygen demand, leading to the development of tissue hypoxia. Different therapeutic approaches exist to increase DO2 and improve microcirculation, such as fluid therapy, transfusion, vasopressors, inotropes, and vasodilators. However, the effects of these agents on microcirculation are quite variable.
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Affiliation(s)
- Jihad Mallat
- Critical Care Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates; Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA; Normandy University, UNICAEN, ED 497, Caen, France.
| | - Nadeem Rahman
- Critical Care Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Fadi Hamed
- Critical Care Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Glenn Hernandez
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontifcia Universidad Católica de Chile, Santiago, Chile
| | - Marc-Olivier Fischer
- Department of Anaesthesiology-Resuscitation and Perioperative Medicine, Normandy University, UNICAEN, Caen University Hospital, Normandy, Caen, France
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Abstract
PURPOSE OF REVIEW The aim of this study was to discuss the implication of microvascular dysfunction in septic shock. RECENT FINDINGS Resuscitation of sepsis has focused on systemic haemodynamics and, more recently, on peripheral perfusion indices. However, central microvascular perfusion is altered in sepsis and these alterations often persist despite normalization of various macro haemodynamic resuscitative goals. Endothelial dysfunction is a key element in sepsis pathophysiology. It is responsible for the sepsis-induced hypotension. In addition, endothelial dysfunction is also implicated involved in the activation of inflammation and coagulation processes leading to amplification of the septic response and development of organ dysfunction. It also promotes an increase in permeability, mostly at venular side, and impairs microvascular perfusion and hence tissue oxygenation.Microvascular alterations are characterized by heterogeneity in blood flow distribution, with adequately perfused areas in close vicinity to not perfused areas, thus characterizing the distributive nature of septic shock. Such microvascular alterations have profound implications, as these are associated with organ dysfunction and unfavourable outcomes. Also, the response to therapy is highly variable and cannot be predicted by systemic hemodynamic assessment and hence cannot be detected by classical haemodynamic tools. SUMMARY Microcirculation is a key element in the pathophysiology of sepsis. Even if microcirculation-targeted therapy is not yet ready for the prime time, understanding the processes implicated in microvascular dysfunction is important to prevent chasing systemic hemodynamic variables when this does not contribute to improve tissue perfusion.
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11
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Flick M, Duranteau J, Scheeren TW, Saugel B. Monitoring of the Sublingual Microcirculation During Cardiac Surgery: Current Knowledge and Future Directions. J Cardiothorac Vasc Anesth 2020; 34:2754-2765. [DOI: 10.1053/j.jvca.2019.10.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 09/29/2019] [Accepted: 10/21/2019] [Indexed: 11/11/2022]
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Bruno RR, Masyuk M, Muessig JM, Binneboessel S, Bernhard M, Bäz L, Franz M, Kelm M, Jung C. Sublingual microcirculation detects impaired perfusion in dehydrated older patients. Clin Hemorheol Microcirc 2020; 75:475-487. [DOI: 10.3233/ch-200859] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND: Dehydration occurs frequently in older patients and constitutes a significant clinical problem. OBJECTIVE: This proof-of-concept study examines whether 1) sublingual measurement in dehydrated old patients is feasible, 2) frailty and incompliance in old, awake patients affects video-quality, 3) dehydration impacts microcirculation METHODS: This prospective observational study included clinically dehydrated patients aged ≥65 years immediately after admission. Dehydration was assessed clinically. A sidestream dark field camera (SDF) was used for measurement. Video-quality was evaluated with MIQS (microcirculation image quality score). Both AVA 4.3C- and AVA POEM-software analyzed the videos. Seventeen patients ≥65 years not showing dehydration served as control. RESULTS: Thirteen patients (8 female) were included. The average age was 83±8 years. The mini-mental test was 17±15 points, the Clinical Frailty Scale 4±3, the Barthel-Index 59±39. None of these parameters correlated with MIQS (3.4±4.2 SD (“acceptable”)). Dehydrated patients had a slightly impaired microcirculation, with a significantly lower percentage of perfused small vessels compared to control (83.1±7.7% versus 88.0±6.0%, P < 0.05). After rehydration, there was acute improvement in the microcirculation. CONCLUSIONS: Sublingual microcirculatory SDF-measurement is both, safe and valid for dehydrated old patients - regardless of frailty, age or cognitive performance. Dehydration leads to an impaired microcirculation.
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Affiliation(s)
- Raphael Romano Bruno
- Department of Cardiology, Pulmonary Diseases, and Vascular Medicine, Medical Faculty, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Maryna Masyuk
- Department of Cardiology, Pulmonary Diseases, and Vascular Medicine, Medical Faculty, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Johanna M. Muessig
- Department of Cardiology, Pulmonary Diseases, and Vascular Medicine, Medical Faculty, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Stephan Binneboessel
- Department of Cardiology, Pulmonary Diseases, and Vascular Medicine, Medical Faculty, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Michael Bernhard
- Emergency Department, University Hospital of Düsseldorf, Düsseldorf, Germany
| | - Laura Bäz
- Department of Internal Medicine I, University Hospital Jena, Jena, Germany
| | - Marcus Franz
- Department of Internal Medicine I, University Hospital Jena, Jena, Germany
| | - Malte Kelm
- Department of Cardiology, Pulmonary Diseases, and Vascular Medicine, Medical Faculty, University Hospital Düsseldorf, Düsseldorf, Germany
- Cardiovascular Research Institute Düsseldorf (CARID), Düsseldorf, Germany
| | - Christian Jung
- Department of Cardiology, Pulmonary Diseases, and Vascular Medicine, Medical Faculty, University Hospital Düsseldorf, Düsseldorf, Germany
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Dilken O, Ergin B, Ince C. Assessment of sublingual microcirculation in critically ill patients: consensus and debate. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:793. [PMID: 32647718 PMCID: PMC7333125 DOI: 10.21037/atm.2020.03.222] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The main concern in shock and resuscitation is whether the microcirculation can carry adequate oxygen to the tissues and remove waste. Identification of an intact coherence between macro- and microcirculation during states of shock and resuscitation shows a functioning regulatory mechanism. However, loss of hemodynamic coherence between the macro and microcirculation can be encountered frequently in sepsis, cardiogenic shock, or any hemodynamically compromised patient. This loss of hemodynamic coherence results in an improvement in macrohemodynamic parameters following resuscitation without a parallel improvement in microcirculation resulting in tissue hypoxia and tissue compromise. Hand-held vital microscopes (HVMs) can visualize the microcirculation and help to diagnose the nature of microcirculatory shock. Although treatment with the sole aim of recruiting the microcirculation is as yet not realized, interventions can be tailored to the needs of the patient while monitoring sublingual microcirculation. With the help of the newly introduced software, called MicroTools, we believe sublingual microcirculation monitoring and diagnosis will be an essential point-of-care tool in managing shock patients.
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Affiliation(s)
- Olcay Dilken
- Department of Intensive Care Med, Laboratory of Translational Intensive Care Med, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.,Department of Intensive Care, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Bulent Ergin
- Department of Intensive Care Med, Laboratory of Translational Intensive Care Med, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Can Ince
- Department of Intensive Care Med, Laboratory of Translational Intensive Care Med, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
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14
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Malbrain MLNG, Langer T, Annane D, Gattinoni L, Elbers P, Hahn RG, De Laet I, Minini A, Wong A, Ince C, Muckart D, Mythen M, Caironi P, Van Regenmortel N. Intravenous fluid therapy in the perioperative and critical care setting: Executive summary of the International Fluid Academy (IFA). Ann Intensive Care 2020; 10:64. [PMID: 32449147 PMCID: PMC7245999 DOI: 10.1186/s13613-020-00679-3] [Citation(s) in RCA: 114] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 05/14/2020] [Indexed: 02/07/2023] Open
Abstract
Intravenous fluid administration should be considered as any other pharmacological prescription. There are three main indications: resuscitation, replacement, and maintenance. Moreover, the impact of fluid administration as drug diluent or to preserve catheter patency, i.e., fluid creep, should also be considered. As for antibiotics, intravenous fluid administration should follow the four Ds: drug, dosing, duration, de-escalation. Among crystalloids, balanced solutions limit acid–base alterations and chloride load and should be preferred, as this likely prevents renal dysfunction. Among colloids, albumin, the only available natural colloid, may have beneficial effects. The last decade has seen growing interest in the potential harms related to fluid overloading. In the perioperative setting, appropriate fluid management that maintains adequate organ perfusion while limiting fluid administration should represent the standard of care. Protocols including a restrictive continuous fluid administration alongside bolus administration to achieve hemodynamic targets have been proposed. A similar approach should be considered also for critically ill patients, in whom increased endothelial permeability makes this strategy more relevant. Active de-escalation protocols may be necessary in a later phase. The R.O.S.E. conceptual model (Resuscitation, Optimization, Stabilization, Evacuation) summarizes accurately a dynamic approach to fluid therapy, maximizing benefits and minimizing harms. Even in specific categories of critically ill patients, i.e., with trauma or burns, fluid therapy should be carefully applied, considering the importance of their specific aims; maintaining peripheral oxygen delivery, while avoiding the consequences of fluid overload.
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Affiliation(s)
- Manu L N G Malbrain
- Department of Intensive Care Medicine, University Hospital Brussels (UZB), Laarbeeklaan 101, 1090, Jette, Belgium. .,Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, Jette, 1090, Belgium. .,International Fluid Academy, Lovenjoel, Belgium.
| | - Thomas Langer
- School of Medicine and Surgery, Milano-Bicocca University, Milan, Italy.,Department of Anesthesia and Critical Care, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Djillali Annane
- General Intensive Care Unit, Raymond Poincaré Hospital (GHU APHP Université Paris Saclay), U1173 Inflammation & Infection, School of Medicine Simone Veil, UVSQ-University Paris Saclay, 104 Boulevard Raymond Poincaré, 92380, Garches, France
| | - Luciano Gattinoni
- Emergency and Intensive Care Medicine, University of Göttingen, Göttingen, Germany
| | - Paul Elbers
- Department of Intensive Care Medicine, Amsterdam UMC, Location VUmc, Amsterdam, The Netherlands
| | - Robert G Hahn
- Karolinska Institutet at Danderyds Hospital (KIDS), Stockholm, Sweden
| | - Inneke De Laet
- Department of Intensive Care Medicine, Ziekenhuis Netwerk Antwerpen, ZNA Stuivenberg, Antwerp, Belgium
| | - Andrea Minini
- Department of Intensive Care Medicine, University Hospital Brussels (UZB), Laarbeeklaan 101, 1090, Jette, Belgium
| | - Adrian Wong
- Department of Intensive Care Medicine and Anaesthesia, King's College Hospital, Denmark Hill, London, UK
| | - Can Ince
- Department of Intensive Care Medicine, Laboratory of Translational Intensive Care Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - David Muckart
- Department of Surgery, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa.,Level I Trauma Unit and Trauma Intensive Care Unit, Inkosi Albert Luthuli Central Hospital, Durban, South Africa
| | - Monty Mythen
- University College London Hospitals, National Institute of Health Research Biomedical Research Centre, London, UK
| | - Pietro Caironi
- SCDU Anestesia e Rianimazione, Azienda Ospedaliero-Universitaria S. Luigi Gonzaga, Orbassano, Italy.,Dipartimento di Oncologia, Università degli Studi di Torino, Turin, Italy
| | - Niels Van Regenmortel
- Department of Intensive Care Medicine, Ziekenhuis Netwerk Antwerpen, ZNA Stuivenberg, Antwerp, Belgium.,Department of Intensive Care Medicine, Ziekenhuis Netwerk Antwerpen, ZNA Stuivenberg, Antwerp, Belgium
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15
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Coppel J, Bountziouka V, Martin D, Gilbert-Kawai E. A comparison of the quality of image acquisition between two different sidestream dark field video-microscopes. J Clin Monit Comput 2020; 35:577-583. [PMID: 32372288 PMCID: PMC8084773 DOI: 10.1007/s10877-020-00514-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 04/27/2020] [Indexed: 12/18/2022]
Abstract
Sidestream dark field (SDF) imaging enables direct visualisation of the microvasculature from which quantification of key variables is possible. The new MicroScan USB3 (MS-U) video-microscope is a hand-held SDF device that has undergone significant technical upgrades from its predecessor, the MicroScan Analogue (MS-A). The MS-U claims superior quality of sublingual microcirculatory image acquisition over the MS-A, however, this has yet to be robustly confirmed. In this manuscript, we therefore compare the quality of image acquisition between these two devices. The microcirculation of healthy volunteers was visualised to generate thirty video images for each device. Two independent raters, blinded to the device type, graded the quality of the images according to the six different traits in the Microcirculation Image Quality Score (MIQS) system. Chi-squared tests and Kappa statistics were used to compare not only the distribution of scores between the devices, but also agreement between raters. MS-U showed superior image quality over MS-A in three of out six MIQS traits; MS-U had significantly more optimal images by illumination (MS-U 95% optimal images, MS-A 70% optimal images (p-value 0.003)), by focus (MS-U 70% optimal images, MS-A 35% optimal images (p-value 0.002)) and by pressure (MS-U 72.5% optimal images, MS-A 47.5% optimal images (p-value 0.02)). For each trait, there was at least 85% agreement between the raters, and all the scores for each trait were independent of the rater (all p-values > 0.05). These results show that the new MS-U provides a superior quality of sublingual microcirculatory image acquisition when compared to old MS-A
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Affiliation(s)
- Jonny Coppel
- University College London Centre for Altitude Space and Extreme Environment Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise and Health, 170 Tottenham Court Road, London, W1T 7HA, UK.
| | - Vassiliki Bountziouka
- Statistical Support Service, Population, Policy and Practice Programme, Institute of Child Health, University College London, London, England
| | - Daniel Martin
- University College London Centre for Altitude Space and Extreme Environment Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise and Health, 170 Tottenham Court Road, London, W1T 7HA, UK.,University College London Division of Surgery and Interventional Science, Royal Free Hospital, London, NW3 2QG, UK
| | - Edward Gilbert-Kawai
- University College London Centre for Altitude Space and Extreme Environment Medicine, UCLH NIHR Biomedical Research Centre, Institute of Sport Exercise and Health, 170 Tottenham Court Road, London, W1T 7HA, UK
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16
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Abstract
PURPOSE OF REVIEW The present review discusses the current role of microcirculatory assessment in the hemodynamic monitoring of critically ill patients. RECENT FINDINGS Videomicroscopic techniques have demonstrated that microvascular perfusion is altered in critically ill patients, and especially in sepsis. These alterations are associated with organ dysfunction and poor outcome. Handheld microscopes can easily be applied on the sublingual area of critically ill patients. Among the specific limitations of these techniques, the most important is that these can mostly investigate the sublingual microcirculation. The representativity of the sublingual area may be questioned, especially as some areas may sometimes be more affected than the sublingual area. Also, evaluation of the sublingual area may be difficult in nonintubated hypoxemic patients. Alternative techniques include vasoreactivity tests using either transient occlusion or performing a thermal challenge. These techniques evaluate the maximal dilatory properties of the microcirculation but do not really evaluate the actual microvascular perfusion. Focusing on the glycocalyx may be another option, especially with biomarkers of glycocalyx degradation and shedding. Evaluation of the glycocalyx is still largely experimental, with different tools still in investigation and lack of therapeutic target. Venoarterial differences in PCO2 are inversely related with microvascular perfusion, and can thus be used as surrogate for microcirculation assessment. Several limitations prevent the regular use in clinical practice. The first is the difficult use of some of these techniques outside research teams, whereas nurse-driven measurements are probably desired. The second important limitation for daily practice use is the lack of uniformly defined endpoint. The final limitation is that therapeutic interventions affecting the microcirculation are not straightforward. SUMMARY Clinical and biological surrogates of microcirculatory assessment can be used at bedside. The role of microvideoscopic techniques is still hampered by the lack of clearly defined targets as well as interventions specifically targeting the microcirculation.
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17
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Abstract
Microvascular dysfunction is a frequent complication of many chronic and acute conditions, especially in the critically ill. Moreover, the severity of microvascular alterations is associated with development of organ dysfunction and poor outcome. The complexities and heterogeneity of critical illness, especially in the elderly patient, requires more mechanistically oriented clinical trials that monitor the effectiveness of existing therapies and of those to come. Recent advances in the ability to obtain physiologically based assessments of microcirculatory function at the bedside will make microcirculatory-guided resuscitation a point of care reality.
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Affiliation(s)
- Can Ince
- Department of Intensive Care, Laboratory of Translational Intensive Care, Erasmus MC, University Medical Center, Dr Molewaterplein 40, 3015 GD Rotterdam, the Netherlands
| | - Daniel De Backer
- Department of Intensive Care, CHIREC Hospitals and Université Libre de Bruxelles, Bd du Triomphe 201, 1160 Brussels, Belgium
| | - Philip R Mayeux
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, 4301 West Markham Street, #611, Little Rock, AR 72212, USA.
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18
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Tavy ALM, de Bruin AFJ, Smits AB, Boerma EC, Ince C, Noordzij PG, Boerma D, van Iterson M. Intestinal Mucosal and Serosal Microcirculation at the Planned Anastomosis during Abdominal Surgery. Eur Surg Res 2020; 60:248-256. [PMID: 31935725 DOI: 10.1159/000505325] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 12/10/2019] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Intestinal blood flow is often named as a key factor in the pathophysiology of anastomotic leakage. The distribution between mucosal and serosal microperfusion during surgery remains to be elucidated. OBJECTIVE The aim of this study was to assess if the mucosal microcirculation of the intestine is more vulnerable to a surgical hit than the serosal microcirculation during surgery. METHODS In an observational cohort study (n = 9 patients), the microcirculation of the bowel serosa and mucosa was visualized with incident dark-field imaging during surgery. At the planned anastomosis, the following microcirculatory parameters were determined: microvascular flow index (MFI), percentage of perfused vessels (PPV), perfused vessel density (PVD), and total vessel density (TVD). Data are presented as median (interquartile range [IQR]). RESULTS Perfusion parameters and vessel density were significantly higher for the mucosa than the serosal microcirculation at the planned site for anastomosis or stoma. Mucosal MFI was 3.00 (IQR 3.00-3.00) compared to a serosal MFI of 2.75 (IQR 2.21-2.94), p = 0.03. The PPV was 99% (IQR 98-100) versus 92% (IQR 66-94), p = 0.01. The TVD was 16.77 mm/mm2 (IQR 13.04-18.01) versus 10.42 mm/mm2 (IQR 9.36-11.81), p = 0.01, and the PVD was 15.44 mm/mm2 (IQR 13.04-17.78) versus 9.02 mm/mm2 (IQR 6.43-9.43), p = 0.01. CONCLUSIONS The mucosal microcirculation was preserved, while lower perfusion of the serosa was found at the planned anastomosis or stoma during surgery. Further research is needed to link our observations to the clinically relevant endpoint of anastomotic leakage.
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Affiliation(s)
- Arthur L M Tavy
- Department of Anesthesiology, Intensive Care and Pain Medicine, St. Antonius Hospital, Nieuwegein, The Netherlands,
| | - Anton F J de Bruin
- Department of Anesthesiology, Intensive Care and Pain Medicine, St. Antonius Hospital, Nieuwegein, The Netherlands
| | - Anke B Smits
- Department of Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands
| | - E Christiaan Boerma
- Department of Intensive Care, Medical Center Leeuwarden, Leeuwarden, The Netherlands
| | - Can Ince
- Department of Intensive Care Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Peter G Noordzij
- Department of Anesthesiology, Intensive Care and Pain Medicine, St. Antonius Hospital, Nieuwegein, The Netherlands
| | - Djamila Boerma
- Department of Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands
| | - Mat van Iterson
- Department of Anesthesiology, Intensive Care and Pain Medicine, St. Antonius Hospital, Nieuwegein, The Netherlands
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19
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Guven G, Hilty MP, Ince C. Microcirculation: Physiology, Pathophysiology, and Clinical Application. Blood Purif 2019; 49:143-150. [PMID: 31851980 DOI: 10.1159/000503775] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 09/28/2019] [Indexed: 12/17/2022]
Abstract
This paper briefly reviews the physiological components of the microcirculation, focusing on its function in homeostasis and its central function in the realization of oxygen transport to tissue cells. Its pivotal role in the understanding of circulatory compromise in states of shock and renal compromise is discussed. Our introduction of hand-held vital microscopes (HVM) to clinical medicine has revealed the importance of the microcirculation as a central target organ in states of critical illness and inadequate response to therapy. Technical and methodological developments have been made in hardware and in software including our recent introduction and validation of automatic analysis software called MicroTools, which now allows point-of-care use of HVM imaging at the bedside for instant availability of functional microcirculatory parameters needed for microcirculatory targeted resuscitation procedures to be a reality.
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Affiliation(s)
- Goksel Guven
- Department of Intensive Care, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Matthias P Hilty
- Department of Intensive Care, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Can Ince
- Department of Intensive Care, Erasmus MC, University Medical Center, Rotterdam, The Netherlands,
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20
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Journal of Clinical Monitoring and Computing 2017/2018 end of year summary: monitoring-and provocation-of the microcirculation and tissue oxygenation. J Clin Monit Comput 2019; 33:201-209. [PMID: 30796643 PMCID: PMC6420417 DOI: 10.1007/s10877-019-00270-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 01/04/2019] [Indexed: 12/22/2022]
Abstract
The microcirculation is the ultimate goal of hemodynamic optimization in the perioperative and critical care setting. In this fourth end-of-year summary of the Journal of Clinical Monitoring and Computing on this topic, we take a closer look at papers published in the last 2 years that focus on this important aspect. The majority of these papers investigated the use of either cerebral or peripheral tissue oxygen saturation, derived non-invasively using near infrared spectroscopy (NIRS). In some of these studies, the microcirculation was “provocated” by inducing short-term tissue hypoxia, allowing the assessment of functional microvascular reserve. Additionally, studies on technical differences between NIRS monitors are summarized, as well as studies investigating the feasibility of NIRS monitoring, mainly in the pediatric patient population. Last but not least, novel monitoring tools allow assessing oxygenation at a (sub)cellular level, and those papers incorporating these techniques are also reviewed here.
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