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Szucs B, Petrekanits M, Fekete M, Varga JT. The use of near-infrared spectroscopy for the evaluation of a 4-week rehabilitation program in patients with COPD. Physiol Int 2021; 108:427-439. [PMID: 34662293 DOI: 10.1556/2060.2021.00185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 08/28/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND Near-infrared spectroscopy (NIRS) technology can evaluate muscle metabolism and oxygenation. NIRS-based oximeters can measure skeletal muscle oxygen delivery and utilization during static and dynamic work non-invasively. Our goal was to assess the value and usability of NIRS technology in chronic obstructive pulmonary disease (COPD) rehabilitation program. METHODS Forty patients with COPD participated in a 4-week inpatient rehabilitation program that included breathing exercises and personalized cycle/treadmill training adjusted to the functional capacity, physical activity and comorbidities of the patients. A NIRS muscle oxygen monitor was used to measure tissue oxygenation and hemoglobin levels. Total hemoglobin index, average muscle oxygenation, minimal and maximal muscle oxygenation were recorded before and after the rehabilitation program. RESULTS Rehabilitation resulted improvement in 6 min walking distance (6MWD:335.3 ± 110. vs. 398.3 ± 126.2 m; P < 0.01), maximal inspiratory pressure (MIP: 57.7 ± 22.7 vs. 63.6 ± 18.0 cmH2O; P < 0.01), chest wall expansion (CWE: 2.84 ± 1.26 vs, 4.00 ± 1.76 cm; P < 0.01), breath hold time (BHT: 25.8 ± 10.6 vs. 29.2 ± 11.6 s; P < 0.01) and grip strength (GS: 24.9 ± 11.9 vs. 27.0 ± 11.4 kg; P < 0.01). Quality of life improvement was monitored by COPD Assessment Test (CAT: 17.00 ± 8.49 vs. 11.89 ± 7.3, P < 0.05). Total hemoglobin index (tHb: 12.8 ± 1.3% vs. 12.8 ± 1.4), average muscle oxygenation (SmO2: 67.5 ± 14.4% vs. 65.2 ± 20.4%) showed a tendency for improvement. Maximal muscle oxygenation decreased (SmO2 max: 98.0 ± 20.5% vs. 90.1 ± 14.3%; P < 0.01). Minimal muscle oxygenation increased (SmO2 min: 42.6 ± 12.6% vs. 54.8 ± 14.3%; P < 0.01). CONCLUSIONS NIRS results showed that muscle oxygenation and microcirculation can be described as a high-risk factor in COPD patients. The 4-week rehabilitation improves functional parameters, quality of life and tissue oxygenation levels in COPD patients.
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Affiliation(s)
- Botond Szucs
- 1 PharmaFlight Research and Training Center, Debrecen, Hungary
| | - Mate Petrekanits
- 2 Institute of Exercise Physiology and Sport Medicine, University of Physical Education, Budapest, Hungary
| | - Monika Fekete
- 3 Department of Public Health, Faculty of Medicine, Semmelweis University, Budapest, Hungary
| | - Janos T Varga
- 4 Department of Pulmonology, Semmelweis University, Budapest, Hungary
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Nicolescu LC, Nicolescu CM, Mihu AG, Balta C. The effect of red blood cell transfusion on peripheral tissue oxygen delivery and consumption in septic patients. Transfus Clin Biol 2020; 28:5-10. [PMID: 33307215 DOI: 10.1016/j.tracli.2020.12.002] [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: 08/13/2020] [Revised: 11/30/2020] [Accepted: 12/01/2020] [Indexed: 10/22/2022]
Abstract
OBJECTIVES The impact of blood transfusion on tissue oxygen delivery (DO2) and tissue oxygen consumption (VO2) is a subject of current clinical studies. The primary objective of this observational study is to evaluate and measure the parameters involved in determining DO2 and VO2, in early phase of septic patients. A secondary objective of this study is to assess the potential benefit of blood transfusion on tissue metabolism by serial measurements of lactic acid (Ac. Lac.). MATERIAL AND METHODS A group of 29 patients were studied, each patient received between one to three units of fresh packed red blood cells (pRBC). Clinical and paraclinical criteria for sepsis as well as the plasma value of haemoglobin (Hb) below 10g/dL represented the inclusion criteria in this study. We evaluated Hb, haematocrit (HCT), arterial blood oxigen saturation (SAO2), central venous oxygen saturation (SCVO2), parameters which are involved in determination of DO2 and VO2, before and after the transfusion of one unit of pRBC. Values of Ac. Lac. were also assessed in order to determine the type of metabolism (aerobic or anaerobic). SCVO2, SAO2, Hb, HCT and Ac. Lac. were determined using Epoc blood analyser. The cardiac output (CO) and systemic vascular resistance (SVR) were monitored during blood transfusion, using Vigileo monitor (Edward's Life Science, PreSep catheter kit). SAO2 was also monitored by pulse-oximetry. RESULTS Changes in Hb, HCT and SCVO2 before and after pRBC transfusion (which further determine VO2) were statistically significant (P<0.001). A statistically significant increase (P<0.001) was obtained in Ac. Lac. values, before and after pRBC transfusion. SAO2 and CO directly involved in producing DO2, were clinically monitored during blood transfusion and the results remained constant. CONCLUSION Results obtained in this clinical study show an increase in DO2 in critically ill septic patients and also an increase in oxygen tissue uptake which is similar to VO2, clearly pointing out the benefit of pRBC transfusion. The benefits of pRBC transfusion on tissue metabolism in critically ill septic patients remain elusive because of lactic acid values increase during and after transfusion. Based on our findings we recommend that Hb values used as a single trigger for pRBC transfusion should be further studied and that additional parameters such as SCVO2 and lactic acid should be considered as possible triggers for transfusion. Values of Hb and HCT should never be neglected.
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Affiliation(s)
- L C Nicolescu
- Department of Public Health, Faculty of Medicine "Vasile Goldis" Western University, str. Liviu Rebreanu nr.86, 310048, Arad, Romania
| | - C M Nicolescu
- Department of Anesthesia and Intensive Care, Emergency County Hospital, Str. Andreny Karoly nr. 2-4, 310037, Arad, Romania.
| | - A G Mihu
- Department of Microbiology, Faculty of Medicine "Vasile Goldis" Western University, str. Liviu Rebreanu, nr. 86, 310048, Arad, Romania; Bioclinica, str. Dreptatii nr. 23,bl. 717, 310300, Arad, Romania
| | - C Balta
- Department of Experimental and Applied Biology, "Aurel Ardelean" Institute of Life Sciences, "Vasile Goldis" Western University, str. Liviu Rebreanu, nr. 86, 310048, Arad, Romania
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Xu LY, Xu D. [Changes in blood oxygen metabolism indices and their clinical significance in children with septic shock]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2017; 19:1124-1128. [PMID: 29046213 PMCID: PMC7389280 DOI: 10.7499/j.issn.1008-8830.2017.10.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 07/21/2017] [Indexed: 06/07/2023]
Abstract
The key to the treatment of septic shock is to provide adequate oxygen supply and improve tissue perfusion. Lactate and central venous oxygen saturation (ScvO2) are commonly used as the indices of oxygen metabolism, but tissue hypoxia may still exist even when lactate and ScvO2 are within the normal range. Arteriovenous difference in carbon dioxide partial pressure (CO2 gap) can accurately reflect oxygen delivery when ScvO2 is in the normal range. This article reviews the advantages and shortages of lactate, lactate clearance rate, ScvO2, and CO2 gap in evaluating tissue hypoxia, in order to provide a reference for treatment and severity evaluation of septic shock.
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Affiliation(s)
- Ling-Yang Xu
- Department of Pediatrics, Second Hospital of Lanzhou University, Lanzhou 730000, China.
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Blattner CN, Santos RSD, Dias FS, Dias AS, Mestriner RG, Vieira SRR. Acute bag-valve breathing maneuvers plus manual chest compression is safe during stable septic shock: a randomized clinical trial. Rev Bras Ter Intensiva 2017; 29:14-22. [PMID: 28444068 PMCID: PMC5385981 DOI: 10.5935/0103-507x.20170004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 11/03/2016] [Indexed: 11/20/2022] Open
Abstract
Objective To evaluate the effects of bag-valve breathing maneuvers combined with
standard manual chest compression techniques on safety, hemodynamics and
oxygenation in stable septic shock patients. Design A parallel, assessor-blinded, randomized trial of two groups. A
computer-generated list of random numbers was prepared by an independent
researcher to allocate treatments. Setting The Intensive Care Unit at Hospital São Lucas,
Pontifícia Universidade Católica do Rio Grande do
Sul. Participants Fifty-two subjects were assessed for eligibility, and 32 were included. All
included subjects (n = 32) received the allocated intervention (n = 19 for
the Experimental Group and n = 13 for the Control Group). Intervention Twenty minutes of bag-valve breathing maneuvers combined with manual chest
compression techniques (Experimental Group) or chest compression, as
routinely used at our intensive care unit (Control Group). Follow-up was
performed immediately after and at 30 minutes after the intervention. Main outcome measure Mean artery pressure. Results All included subjects completed the trial (N = 32). We found no relevant
effects on mean artery pressure (p = 0.17), heart rate (p = 0.50) or mean
pulmonary artery pressure (p = 0.89) after adjusting for subject age and
weight. Both groups were identical regarding oxygen consumption after the
data adjustment (p = 0.84). Peripheral oxygen saturation tended to increase
over time in both groups (p = 0.05), and there was no significant
association between cardiac output and venous oxygen saturation (p = 0.813).
No clinical deterioration was observed. Conclusion A single session of bag-valve breathing maneuvers combined with manual chest
compression is hemodynamically safe for stable septic-shocked subjects over
the short-term.
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Affiliation(s)
- Clarissa Netto Blattner
- Faculdade de Enfermagem, Nutrição e Fisioterapia, Pontifícia Universidade Católica do Rio Grande do Sul - Porto Alegre (RS), Brasil
| | | | - Fernando Suparregui Dias
- Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul - Porto Alegre (RS), Brasil.,Unidade de Terapia Intensiva, Hospital Pompeia - Caxias do Sul (RS), Brasil
| | - Alexandre Simões Dias
- Departamento de Fisioterapia, Hospital das Clínicas de Porto Alegre, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul - Porto Alegre (RS), Brasil
| | - Régis Gemerasca Mestriner
- Faculdade de Enfermagem, Nutrição e Fisioterapia, Pontifícia Universidade Católica do Rio Grande do Sul - Porto Alegre (RS), Brasil
| | - Silvia Regina Rios Vieira
- Unidade de Terapia Intensiva, Hospital das Clínicas de Porto Alegre, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul - Porto Alegre (RS), Brasil
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Perioperative fluid therapy: defining a clinical algorithm between insufficient and excessive. J Clin Anesth 2016; 35:384-391. [DOI: 10.1016/j.jclinane.2016.08.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 08/09/2016] [Indexed: 01/03/2023]
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Prospective evaluation of regional oxygen saturation to estimate central venous saturation in sepsis. J Clin Monit Comput 2015; 29:443-53. [PMID: 25757404 DOI: 10.1007/s10877-015-9683-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 02/27/2015] [Indexed: 01/01/2023]
Abstract
Current treatment guidelines for sepsis claim an early goal-directed hemodynamic optimization including fluid resuscitation, use of vasopressors and inotropic agents. We investigated the correlation between the prominent treatment goal central venous saturation (ScvO2) and the frontal and the thenar regional oxygen saturation (rSO2) measured by near infrared spectroscopy. Secondary, we examined the value of ScvO2, lactate levels and rSO2 as surrogate markers of an impaired tissue oxygenation for outcome prediction in sepsis. This prospective, observational study was performed at the surgical intensive care unit of the University Hospital Giessen. A total of 50 patients with sepsis, severe sepsis or septic shock were included. ScvO2, rSO2 and lactate were measured at sepsis diagnosis (baseline), 24 and 48 h, thereafter. We investigated the predictive value of frontal and thenar rSO2 for a decreased SvcO2 under 70%. For survivor and non-survivors ScvO2, rSO2 and lactate were analysed. Patients with ScvO2 >70% showed a trend to higher levels of fontal rSO2 (62.81 ± 8.06 vs. 53.54 ± 15.48; p = 0.058). ROC-analysis revealed a minor prediction of a decreased ScvO2 by frontal rSO2 levels at baseline (AUC = 0.687; 95% CI 0.511-0.863; p = 0.047). Combined measurements of lactate and ScvO2 showed significantly elevated mortality for patients with ScvO2 ≥70% and lactate levels ≥2.5 mmol/l (log rank test p = 0.004). In the group with ScvO2 <70% and lactate levels <2.5 mmol/l no patients died during the observation period. Frontal rSO2 correlates with ScvO2 but both frontal and thenar rSO2 do not exactly discriminate between patients with high or low ScvO2 in sepsis. The combination of elevated lactate >2.5 mmol/l and ScvO2 >70 % is highly associated with poor outcome in ICU patients with sepsis, severe sepsis and septic shock.
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Abstract
Despite the multiple causes of the shock state, all causes possess the common abnormality of oxygen supply not meeting tissue metabolic demands. Compensatory mechanisms may mask the severity of hypoxemia and hypoperfusion, since catecholamines and extracellular fluid shifts initially compensate for the physiologic derangements associated with patients in shock. Despite the achievement of normal physiologic parameters after resuscitation, significant metabolic acidosis may continue to be present in the tissues, as evidenced by increased lactate levels and metabolic acidosis. This review discusses the major endpoints of resuscitation in clinical use.
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Affiliation(s)
- Ramon F Cestero
- Division of Trauma and Emergency Surgery, Department of Surgery, UT Health Science Center San Antonio, 7703 Floyd Curl Drive, Mail Code 7740, San Antonio, TX 78229-3900, USA.
| | - Daniel L Dent
- Division of Trauma and Emergency Surgery, Department of Surgery, UT Health Science Center San Antonio, 7703 Floyd Curl Drive, Mail Code 7740, San Antonio, TX 78229-3900, USA
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Kocsi S, Demeter G, Érces D, Kaszaki J, Molnár Z. Central venous-to-arterial CO2-gap may increase in severe isovolemic anemia. PLoS One 2014; 9:e105148. [PMID: 25137377 PMCID: PMC4138121 DOI: 10.1371/journal.pone.0105148] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 06/25/2014] [Indexed: 11/18/2022] Open
Abstract
Despite blood transfusions are administered to restore adequate tissue oxygenation, transfusion guidelines consider only hemoglobin as trigger value, which gives little information about the balance between oxygen delivery and consumption. Central venous oxygen saturation is an alternative, however its changes reflect systemic metabolism and fail to detect regional hypoxia. A complementary parameter to ScvO2 may be central venous-to-arterial carbon dioxide difference (CO2-gap). Our aim was to investigate the change of alternative transfusion trigger values in experimental isovolemic anemia. After splenectomy, anesthetized Vietnamese mini pigs (n = 13, weight range: 18–30 kg) underwent controlled bleeding in five stages (T1–T5). During each stage approximately 10% of the estimated starting total blood volume was removed and immediately replaced with an equal volume of colloid. Hemodynamic measurements and blood gas analysis were then performed. Each stage of bleeding resulted in a significant fall in hemoglobin, the O2-extraction increased significantly from T3 and ScvO2 showed a similar pattern and dropped below the physiological threshold of 70% at T4. By T4 CO2-gap increased significantly and well correlated with VO2/DO2 and ScvO2. To our knowledge, this is the first study to show that anemia caused altered oxygen extraction may have an effect on CO2-gap.
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Affiliation(s)
- Szilvia Kocsi
- Department of Anaesthesiology and Intensive Therapy, University of Szeged, Szeged, Hungary
- Department of Anaesthesiology and Intensive Therapy, Hungarian Defence Forces Military Hospital, Budapest, Hungary
- * E-mail:
| | - Gábor Demeter
- Department of Anaesthesiology and Intensive Therapy, University of Szeged, Szeged, Hungary
| | - Dániel Érces
- Institute of Surgical Research, University of Szeged, Szeged, Hungary
| | - József Kaszaki
- Institute of Surgical Research, University of Szeged, Szeged, Hungary
| | - Zsolt Molnár
- Department of Anaesthesiology and Intensive Therapy, University of Szeged, Szeged, Hungary
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9
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Reid M. Central venous oxygen saturation: analysis, clinical use and effects on mortality. Nurs Crit Care 2013; 18:245-50. [PMID: 23968443 DOI: 10.1111/nicc.12028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 04/17/2013] [Accepted: 04/18/2013] [Indexed: 01/03/2023]
Abstract
AIMS AND OBJECTIVES The aim of this literature review was to provide a clear definition of central venous oxygen saturation (ScvO₂), highlight the differences between ScvO₂ and mixed venous oxygen saturation (SvO₂), show how it can be used clinically and the effect central venous oxygen saturation has on mortality. BACKGROUND Many articles concentrate on the individual aspects of ScvO₂, such as its use in early goal-directed therapy, but few provide a full overview of what it means, how to interpret results and how it can be used clinically. SEARCH STRATEGIES Keywords were searched for including central venous oxygen saturation ScvO₂ mixed venous oxygen saturations ScvO₂ early goal-directed therapy sepsis and mortality. Where possible only publications within the last 10 years were used but key publications were not excluded if they were out with this time frame. CONCLUSIONS Central venous oxygen saturation (ScvO₂) is a very important measurement which can be easily taken in a critical care environment by both medical and nursing staff. It provides an understanding of the patient's oxygen delivery, oxygen consumption and cardiac output. It has a key role within early goal-directed therapy and has been shown to decrease mortality when taken and analysed appropriately. RELEVANCE TO CLINICAL PRACTICE This literature review will highlight to nursing staff within the critical care environment the importance of central venous oxygen saturation measurement and interpretation. By raising awareness of the importance of this measurement it is hoped nursing staff will be proactive in both taking this test and analysing the results, therefore facilitating better care for the septic, critically ill patient and improving outcomes for these patients.
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Affiliation(s)
- Megan Reid
- Staff Nurse, Intensive Care Unit in the Royal Alexandra Hospital, Paisley, UK.
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10
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Lichtenstern C, Koch C, Röhrig R, Rosengarten B, Henrich M, Weigand MA. [Near-infrared spectroscopy in sepsis therapy : predictor of a low central venous oxygen saturation]. Anaesthesist 2012; 61:883-91. [PMID: 23011045 DOI: 10.1007/s00101-012-2087-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 08/27/2012] [Accepted: 08/30/2012] [Indexed: 12/22/2022]
Abstract
BACKGROUND Early goal-directed hemodynamic optimization has become a cornerstone of sepsis therapy. One major defined goal is to achieve adequate central venous oxygen saturation (SO(2)). This study aimed to investigate the correlation between central venous SO(2) and frontal cerebral near-infrared spectroscopy (NIRS) measurement in patients with severe sepsis and septic shock. The NIRS method provides non-invasive measurement of regional oxygen saturation (rSO(2)) in tissues approximately 2 cm below the optical NIRS sensors which depends on arterial, capillary and venous blood. Thus this system gives site-specific real-time data about the balance of oxygen supply and demand. METHODS This was a secondary analysis from a prospective study of surgical intensive care (ICU) patients in the early phase of severe sepsis or septic shock. Bilateral cerebral rSO(2), central venous SO(2), arterial oxygen saturation (S(a)O(2)) and other surrogate parameters of oxygen supply, such as hemoglobin, partial pressure of oxygen and oxygen content in arterial blood were recorded. RESULTS A total of 16 ICU patients (4 women, median age 65.5 years) were included in the study. As sepsis focus an intra-abdominal infection was detected in 62.5 % of patients, severe pneumonia was determined in 31.3 % and skin and soft tissue infections were recognized in 12.5 %. At study inclusion 50 % of patients had septic shock, the median sequential organ failure assessment (SOFA) score was 10.2 (interquartile range 5.25-8.75) and the median acute physiology and chronic health evaluation II (APACHE II) score was 26 (range 23.25-29.75). Mortality at day 28 was 37.5 %. Minimum rSO(2) (median 58) and right-sided rSO(2) (median 58) values showed a significant correlation in the analysis of receiver operating characteristics (area under the curve 0.844, p= 0.045). A central venous SO(2)< 70 % was indicated by rSO(2)< 56.5 with sensitivity and specificity of 75 % and 100 %, respectively. CONCLUSIONS Cerebral NIRS could provide a fast and easily available side effect-free monitoring that could be used in addition to established procedures for goal-directed treatment in the early phase of sepsis. Further studies should be made in a larger population to verify the correlation found and to investigate the impact of NIRS-directed resuscitation treatment in early sepsis.
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Affiliation(s)
- C Lichtenstern
- Klinik für Anaesthesiologie und Operative Intensivmedizin, Universitätsklinikum Gießen und Marburg, Standort Gießen, Rudolf-Buchheim-Str. 7, 35392, Gießen, Deutschland.
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KOCSI S, DEMETER G, FOGAS J, ÉRCES D, KASZAKI J, MOLNÁR Z. Central venous oxygen saturation is a good indicator of altered oxygen balance in isovolemic anemia. Acta Anaesthesiol Scand 2012; 56:291-7. [PMID: 22260228 DOI: 10.1111/j.1399-6576.2011.02622.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2011] [Indexed: 01/20/2023]
Abstract
BACKGROUND Red blood cell transfusion is done primarily as a means to improve oxygen delivery (DO₂). Current transfusion guidelines are based solely on hemoglobin levels, regardless of actual DO₂ need. As central venous oxygen saturation (ScvO₂) may reflect imbalances in DO₂ and consumption (VO₂) the aim of this study was to investigate the value of ScvO₂ as an indicator of oxygen balance in isovolemic anemia. METHODS After splenectomy, anesthetized Vietnamese mini pigs (n = 13, weight range: 18-30 kg) underwent controlled bleeding in five stages (T₀-T₅). During each stage approximately 10% of the estimated starting total blood volume was removed and immediately replaced with an equal volume of colloid. Hemodynamic measurements and blood gas analysis were then performed. RESULTS Each stage of bleeding resulted in a significant fall in hemoglobin, T₀ : 125 (113-134) to T(5) : 49 (43-55) g/l [T₀ : 7.7 (6.9-8.2) to T₅ : 3.0 (2.6-3.4) mmol/l]. The O₂-extraction (VO₂/DO₂) increased significantly only from T₃ : 35 (21-40) %, P < 0.05. The change of ScvO₂ showed a similar pattern and dropped below the physiological threshold of 70% at T₄ : 68 (61-76) %. At this point, hemoglobin was below the recommended transfusion trigger value, 59 (53-67) g/l [3.6 (3.3-4.1) mmol/l]. There was a strong significant association between ScvO₂< 70%) and VO₂/DO₂ > 30%): r = -0.71, r² = 0.50, P < 0.001. CONCLUSION The results of this study show that ScvO₂ reflects changes of VO₂/DO₂ in isovolemic anemia better than Hb alone, therefore it may be used as an additional indicator of blood transfusion in clinical practice.
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Affiliation(s)
- S. KOCSI
- Department of Anaesthesiology and Intensive Therapy; Faculty of Medicine; University of Szeged; Szeged; Hungary
| | - G. DEMETER
- Department of Anaesthesiology and Intensive Therapy; Faculty of Medicine; University of Szeged; Szeged; Hungary
| | - J. FOGAS
- Department of Anaesthesiology and Intensive Therapy; Faculty of Medicine; University of Szeged; Szeged; Hungary
| | - D. ÉRCES
- Institute of Surgical Research; Faculty of Medicine; University of Szeged; Szeged; Hungary
| | - J. KASZAKI
- Institute of Surgical Research; Faculty of Medicine; University of Szeged; Szeged; Hungary
| | - Z. MOLNÁR
- Department of Anaesthesiology and Intensive Therapy; Faculty of Medicine; University of Szeged; Szeged; Hungary
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12
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Christensen M. Mixed venous oxygen saturation monitoring revisited: thoughts for critical care nursing practice. Aust Crit Care 2011; 25:78-90. [PMID: 22112670 DOI: 10.1016/j.aucc.2011.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 07/21/2011] [Accepted: 10/18/2011] [Indexed: 10/15/2022] Open
Abstract
BACKGROUND Less invasive methods of determining cardiac output are now readily available. Using indicator dilution technique, for example has made it easier to continuously measure cardiac output because it uses the existing intra-arterial line. Therefore gone is the need for a pulmonary artery floatation catheter and with it the ability to measure left atrial and left ventricular work indices as well the ability to monitor and measure a mixed venous saturation (SvO(2)). PURPOSE The aim of this paper is to put forward the notion that SvO(2) provides valuable information about oxygen consumption and venous reserve; important measures in the critically ill to ensure oxygen supply meets cellular demand. In an attempt to portray this, a simplified example of the septic patient is offered to highlight the changing pathophysiological sequelae of the inflammatory process and its importance for monitoring SvO(2). RELEVANCE TO CLINICAL PRACTICE SvO(2) monitoring, it could be argued, provides the gold standard for assessing arterial and venous oxygen indices in the critically ill. For the bedside ICU nurse the plethora of information inherent in SvO(2) monitoring could provide them with important data that will assist in averting potential problems with oxygen delivery and consumption. However, it has been suggested that central venous saturation (ScvO(2)) might be an attractive alternative to SvO(2) because of its less invasiveness and ease of obtaining a sample for analysis. There are problems with this approach and these are to do with where the catheter tip is sited and the nature of the venous admixture at this site. Studies have shown that ScvO(2) is less accurate than SvO(2) and should not be used as a sole guiding variable for decision-making. These studies have demonstrated that there is an unacceptably wide range in variance between ScvO(2) and SvO(2) and this is dependent on the presenting disease, in some cases SvO(2) will be significantly lower than ScvO(2). CONCLUSION Whilst newer technologies have been developed to continuously measure cardiac output, SvO(2) monitoring is still an important adjunct to clinical decision-making in the ICU. Given the information that it provides, seeking alternatives such as ScvO(2) or blood samples obtained from femorally placed central venous lines, can unnecessarily lead to inappropriate treatment being given or withheld. Instead when using ScvO(2), trending of this variable should provide clinical determinates that are useable for the bedside ICU nurse, remembering that in most conditions SvO(2) will be approximately 16% lower.
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Affiliation(s)
- Martin Christensen
- Clinical Research Centre, MD11, 10 Medical Drive, Singapore, 117597, Singapore.
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Strunden MS, Heckel K, Goetz AE, Reuter DA. Perioperative fluid and volume management: physiological basis, tools and strategies. Ann Intensive Care 2011; 1:2. [PMID: 21906324 PMCID: PMC3159903 DOI: 10.1186/2110-5820-1-2] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 03/21/2011] [Indexed: 12/21/2022] Open
Abstract
Fluid and volume therapy is an important cornerstone of treating critically ill patients in the intensive care unit and in the operating room. New findings concerning the vascular barrier, its physiological functions, and its role regarding vascular leakage have lead to a new view of fluid and volume administration. Avoiding hypervolemia, as well as hypovolemia, plays a pivotal role when treating patients both perioperatively and in the intensive care unit. The various studies comparing restrictive vs. liberal fluid and volume management are not directly comparable, do not differ (in most instances) between colloid and crystalloid administration, and mostly do not refer to the vascular barrier's physiologic basis. In addition, very few studies have analyzed the use of advanced hemodynamic monitoring for volume management. This article summarizes the current literature on the relevant physiology of the endothelial surface layer, discusses fluid shifting, reviews available research on fluid management strategies and the commonly used fluids, and identifies suitable variables for hemodynamic monitoring and their goal-directed use.
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Affiliation(s)
- Mike S Strunden
- Center of Anesthesiology and Intensive Care Medicine, Department of Anesthesiology, Hamburg-Eppendorf University Medical Center Martinistraße 52, 20246 Hamburg, Germany.
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