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Mixed Venous Oxygen Saturation (mixed + venous_oxygen_saturation)
Selected AbstractsMixed Venous Oxygen Saturation in the Diagnosis of Cardiac TamponadeJOURNAL OF CARDIAC SURGERY, Issue 2 2008David A. Fullerton M.D. No abstract is available for this article. [source] Mixed venous oxygen saturation is a prognostic marker after surgery for aortic stenosisACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2010J. HOLM Background: Adequate monitoring of the hemodynamic state is essential after cardiac surgery and is vital for medical decision making, particularly concerning hemodynamic management. Unfortunately, commonly used methods to assess the hemodynamic state are not well documented with regard to outcome. Mixed venous oxygen saturation (SvO2) was therefore investigated after cardiac surgery. Methods: Detailed data regarding mortality were available on all patients undergoing aortic valve replacement for isolated aortic stenosis during a 5-year period in the southeast region of Sweden (n=396). SvO2 was routinely measured on admission to the intensive care unit (ICU) and registered in a database. A receiver operating characteristics (ROC) analysis of SvO2 in relation to post-operative mortality related to cardiac failure and all-cause mortality within 30 days was performed. Results: The area under the curve (AUC) was 0.97 (95% CI 0.96,1.00) for mortality related to cardiac failure (P=0.001) and 0.76 (95% CI 0.53,0.99) for all-cause mortality (P=0.011). The best cutoff for mortality related to cardiac failure was SvO2 53.7%, with a sensitivity of 1.00 and a specificity of 0.94. The negative predictive value was 100%. The best cutoff for all-cause mortality was SvO2 58.1%, with a sensitivity of 0.75 and a specificity of 0.84. The negative predictive value was 99.4%. Post-operative morbidity was also markedly increased in patients with a low SvO2. Conclusion: SvO2, on admission to the ICU after surgery for aortic stenosis, demonstrated excellent sensitivity and specificity for post-operative mortality related to cardiac failure and a fairly good AUC for all-cause mortality, with an excellent negative predictive value. [source] Intranasal cooling with or without intravenous cold fluids during and after cardiac arrest in pigsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2010L. COVACIU Background: Intranasal balloon catheters circulated with cold saline have previously been used for the induction and maintenance of selective brain cooling in pigs with normal circulation. In the present study, we investigated the feasibility of therapeutic hypothermia initiation, maintenance and rewarming using such intranasal balloon catheters with or without addition of intravenous ice-cold fluids during and after cardiac arrest treatment in pigs. Material and methods: Cardiac arrest was induced in 20 anaesthetised pigs. Following 8 min of cardiac arrest and 1 min of cardiopulmonary resuscitation (CPR), cooling was initiated after randomisation with either intranasal cooling (N) or combined with intravenous ice-cold fluids (N+S). Hypothermia was maintained for 180 min, followed by 180 min of rewarming. Brain and oesophageal temperatures, haemodynamic variables and intracranial pressure (ICP) were recorded. Results: Brain temperatures reductions after cooling did not differ (3.8 ± 0.7 °C in the N group and 4.3 ± 1.5 °C in the N+S group; P=0.47). The corresponding body temperature reductions were 3.6 ± 1.2 °C and 4.6 ± 1.5 °C (P=0.1). The resuscitation outcome was similar in both groups. Mixed venous oxygen saturation was lower in the N group after cooling and rewarming (P=0.024 and 0.002, respectively) as compared with the N+S group. ICP was higher after rewarming in the N group (25.2 ± 2.9 mmHg; P=0.01) than in the N+S group (15.7 ± 3.3 mmHg). Conclusions: Intranasal balloon catheters can be used for therapeutic hypothermia initiation, maintenance and rewarming during CPR and after successful resuscitation in pigs. [source] Mixed venous oxygen desaturation during early mobilization after coronary artery bypass surgeryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2005I. Kirkeby-Garstad Background:, Early postoperative mobilization induces a marked reduction in mixed venous oxygen saturation (SvO2) after aortic valve replacement. We investigated whether a similar desaturation occurs among coronary artery bypass grafting (CABG) patients, and if the desaturation was related to the preoperative ejection fraction (EF). Methods:, Thirty-one CABG patients with a wide range in EF were included in an open observational study. We recorded hemodynamic and oxygenation variables during mobilization on postoperative day 1 and day 2 using a pulmonary artery catheter. Results:, Patients with an EF ranging from 24 to 87% were mobilized without clinical problems. SvO2 at rest was 65.4 ± 4.9% (mean ± SD) on day 1 and 64.3 ± 5.8% on day 2 (NS). During mobilization, cardiac index and oxygen delivery were reduced while oxygen consumption was increased (P -values: 0.000, 0.007 and 0.000, respectively). Consequently, oxygen extraction increased, resulting in a marked reduction in SvO2,42.9 ± 8.3% on day 1 and 47.4 ± 8.5% on day 2 (P = 0.025 between days). Several pre-, intra- and postoperative factors were tested as possible predictors for SvO2 during mobilization. No factor contributed substantially. Conclusion:, Patients with CABG exhibit a marked desaturation during early postoperative mobilization. Preoperative ejection fraction did not affect SvO2 during exercise. The clinical consequences and underlying mechanism require further investigation. [source] The angiotensin II receptor blocker candesartan improves survival and mesenteric perfusion in an acute porcine endotoxin modelACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2004M. Laesser Background:, Blockade of the angiotensin II type 1 (AT1) receptor has been demonstrated to ameliorate splanchnic hypoperfusion in acute experimental circulatory failure. This study focused on hemodynamic changes and survival in pigs treated with AT1 blockade prior to or during acute endotoxinemia. Methods:,Escherichia coli lipopolysaccharide endotoxin was infused in anesthetized and mechanically ventilated pigs. Systemic, renal, mesenteric and jejunal mucosal perfusion as well as systemic oxygen and acid-base balance were monitored. The selective AT1 receptor blocker candesartan was administered prior to as well as during endotoxinemia. Control animals received the saline vehicle. Results:, Pre-treatment with candesartan resulted in higher survival rate (83%, 10 out of 12 animals) compared with 50% (6 of 12) in control animals and 27% (3 of 11) in animals treated during endotoxinemia. Pre-treatment with candesartan resulted in higher cardiac output, mixed venous oxygen saturation, arterial standard base-excess, portal venous blood flow during endotoxin infusion compared with controls and animals treated during endotoxinemia. No adverse effects were found on neither systemic nor renal circulation. Conclusion:, The favorable results of AT1 receptor blockade prior to endotoxinemia are lost when blockade is established during endotoxinemia demonstrating the importance of the renin-angiotensin system and its dynamic involvement in acute endotoxinemic shock. [source] A noninvasive estimation of mixed venous oxygen saturation using near-infrared spectroscopy by cerebral oximetry in pediatric cardiac surgery patientsPEDIATRIC ANESTHESIA, Issue 6 2005TIA A. TORTORIELLO MD FAAP Summary Background :,Near-infrared spectroscopy (NIRS) is a noninvasive optical monitor of regional cerebral oxygen saturation (rSO2). The aim of this study was to validate the use of NIRS by cerebral oximetry in estimating invasively measured mixed venous oxygen saturation (SvO2) in pediatric postoperative cardiac surgery patients. Methods :,Twenty patients were enrolled following cardiac surgery with intraoperative placement of a pulmonary artery (PA) or superior vena cava (SVC) catheter. Five patients underwent complete biventricular repair , complete atrioventricular canal (n = 3) and other (n = 2). Fifteen patients with functional single ventricle underwent palliative procedures , bidirectional Glenn (n = 11) and Fontan (n = 4). Cerebral rSO2 was monitored via NIRS (INVOS 5100) during cardiac surgery and 6 h postoperatively. SvO2 was measured from blood samples obtained via an indwelling PA or SVC catheter and simultaneously correlated with rSO2 by NIRS at five time periods: in the operating room after weaning from cardiopulmonary bypass, after sternal closure, and in the CICU at 2, 4, and 6 h after admission. Results :,Each patient had five measurements (total = 100 comparisons). SvO2 obtained via an indwelling PA or SVC catheter for all patients correlated with rSO2 obtained via NIRS: Pearson's correlation coefficient of 0.67 (P < 0.0001) and linear regression of r2 = 0.45 (P < 0.0001). Separate linear regression of the complete biventricular repairs demonstrated an r = 0.71, r2 = 0.50 (P < 0.0001). Bland,Altman analysis showed a bias of +3.3% with a precision of 16.6% for rSO2 as a predictor of SvO2 for all patients. Cerebral rSO2 was a more accurate predictor of SvO2 in the biventricular repair patients (bias ,0.3, precision 11.8%), compared with the bidirectional Glenn and Fontan patients. Conclusions :,Regional cerebral oximetry via NIRS correlates with SvO2 obtained via invasive monitoring. However, the wide limits of agreement suggest that it may not be possible to predict absolute values of SvO2 for any given patient based solely on the noninvasive measurement of rSO2. Near-infrared spectroscopy, using the INVOS 5100 cerebral oximeter, could potentially be used to indicate trends in SVO2, but more studies needs to be performed under varying clinical conditions. [source] Comparison of central venous oxygen saturation and mixed venous oxygen saturation during liver transplantationANAESTHESIA, Issue 4 2009A. El Masry Summary Central venous catheterisation is commonly performed during major surgery and intensive care, and it would be useful if central venous oxygen saturation could function as a surrogate for mixed venous oxygen saturation. We studied 50 patients undergoing living related liver transplantation. Blood samples were taken simultaneously from central venous and pulmonary artery catheters at nine time points during the pre-anhepatic, anhepatic, and postanhepatic phases. Four hundred and fifty sets of measurement were obtained. There was a good correlation between central venous oxygen saturation and mixed venous oxygen saturation. The mean (SD) difference (95% limit of agreement) was lowest at the first time point (1.06 (0.65)%, ,1.94% to 2.7%) and then increased throughout the study but remained acceptable. The change in mixed venous oxygen and central venous oxygen saturations occurred mostly in parallel and as a result changes in mixed venous oxygen saturation were reflected adequately in the change in central venous oxygen saturation. The correlation between mixed venous oxygen saturation and cardiac output was poor. [source] Hemodynamic Effects of Intravenous Fat Emulsion in an Animal Model of Severe Verapamil Toxicity Resuscitated with Atropine, Calcium, and SalineACADEMIC EMERGENCY MEDICINE, Issue 2 2007Theodore C. Bania MD Background Intravenous fat emulsion (IFE) decreases cardiotoxicity from several lipid-soluble drugs, including verapamil. Objectives To verify if the addition of IFE to the standard treatment of severe verapamil toxicity would improve hemodynamics and survival. Methods Fourteen dogs were instrumented to measure systolic blood pressure, diastolic blood pressure, mean arterial pressure (MAP), heart rate, cardiac output, central venous pressures, left ventricular pressure changes over time, mixed venous oxygen saturation, pH, and base excess. Verapamil toxicity, defined as a 50% decrease in MAP, was induced with verapamil at 6 mg/kg/hr and maintained for 30 minutes by titrating the verapamil infusion rate. Following verapamil toxicity, the verapamil infusion rate was changed to 2 mg/kg/hr and continued for 90 minutes. All dogs were resuscitated with atropine (0.04 mg/kg intravenously) and calcium chloride (15 mg/kg intravenously every 5 minutes for three doses) and then randomized to receive either IFE (7 mg/kg of 20%) intravenously or equivalent volumes of 0.9% normal saline over 30 minutes. Measurements were recorded for 120 minutes by investigators blinded to the treatment. Data were analyzed using analysis of variance, survival analysis, and log-rank test. Results Before the 30-minute IFE or normal saline infusion, there were no differences in hemodynamic parameters. After IFE or normal saline infusion, the IFE-treated group had higher MAP at 30 minutes (95% confidence interval [CI] = 5.6 to 44.7 mm Hg), 45 minutes (95% CI = 10.8 to 50.0 mm Hg), and 60 minutes (95% CI = 10.2 to 53.1 mm Hg). Kaplan,Meier 120-minute survival rate was 14% (95% CI = 0.5% to 53%) for the saline group as compared with 100% (95% CI = 59% to 100%) for the IFE group (p = 0.01). Conclusions Standard resuscitation and IFE increase MAP and survival in an animal model of severe verapamil toxicity compared with standard resuscitation alone. [source] | ||||||||||