Venous Oxygen Saturation In Patients Research Articles

Comparison of Mixed Venous Oxygen Saturation and Premembranous Venous Oxygen Saturation in Patients on Peripheral Venous-Arterial Extracorporeal Membrane Oxygenation.

In patients on veno-arterial extracorporeal membrane oxygenation (ECMO) premembranous venous oxygen saturation (Spm-vO2) is continuously displayed on the ECMO console. However, the concordance between Spm-vO2 and mixed venous oxygen saturation (SvO2) remains largely unexplored. Our single-center retrospective study included adult patients who had paired SvO2 and Spm-vO2 readings within 15 minutes of each other, on peripherally cannulated Vf ivc-A ECMO and a pulmonary artery using catheter (PAC). The 82 pairs of observations showed a mean difference of 11.37% (95% limits of agreement -6.0 to 28.74, p < 0.001) between Spm-vO2 and SvO2. Although the two values correlated with each other (r = 0.51, p < 0.01), the difference between the paired measurements was larger at lower values of SvO2 (3.72 ± 6.38% when SvO2 >80%, 11.79±7.46% when SvO2 between 60% and 80%, and 18.81±12.09% when SvO2 <60%). The equation SvO2 = 1.2* Spm-vO2 - 28.03 was obtained by Passing Bablok regression. Cardiac index calculated by Spm-vO2 and SvO2 differed by 0.8L/minute/m2 (95% limits of agreement -0.52 to 2.17, p < 0.001). In peripheral VA-ECMO, Spm-vO2 is consistently higher than SvO2, with more discordance at lower saturation levels. Using Spm-vO2 to estimate cardiac output using Fick method yields inaccurate results.

Prognostic value of central venous oxygen saturation during anesthesia for cardiac surgery.

Background:During cardiac surgery, CPB machine pumps blood instead of the heart affecting blood flow and hence blood perfusion of all tissues. One important marker of blood perfusion is central venous oxygen saturation. Relationship between central venous oxygen saturation and patient morbidity and mortality is an indicator for the reliability of blood lactate as a perfusion marker.Methods:In a prospective observational study, 66 patients admitted to Sohag university hospital and Sohag Heart Institute in the period between October 2017 and April 2019 for open cardiac surgery were enrolled. Immediately after induction of anesthesia, the first sample of venous blood gas was obtained from central venous catheter. For measuring of central venous oxygen saturation, the next samples were obtained just before CPB weaning, the next after 24 hours of staying ICU and the last sample were obtained after 48 hours of staying ICU.Results:Central venous oxygen saturation in correlation to ICU length of stay showed significant change in central venous oxygen saturation in patients with favorable outcome. Central venous oxygen saturation in correlation to postoperative duration of mechanical ventilation showed significant change in central venous oxygen saturation in patients with favorable outcome. Central venous oxygen saturation in correlation to postoperative complications showed significant change in central venous oxygen saturation in patients with favorable outcome.Conclusion: Measuring ScvO2 at 4 points during and after open-heart surgery showed their prognostic value, regarding results for ScvO2: ICU length of stay, duration of mechanical ventilation and complications.

Predictive role of central venous oxygen saturation in patients with acute type i respiratory failure

Background Global oxygenation can be indirectly measured by the measurement of venous oxygen saturation.Objective To estimate the value of central venous oxygen saturation (ScvO2) to predict the outcome in type 1 acute respiratory failure (ARF) patients admitted to the respiratory ICU and to assess its potential association with mortality.Patients and methods The study included 62 type 1 ARF patients admitted to respiratory ICU with indication for a central venous catheter. ScvO2 was measured from right atrium blood samples at admission, 3 and 7 days later. Arterial blood gas was assessed simultaneously. The patients were classified into three groups according to the ScvO2 level (at admission): high more than 75%, normal 65–75%, and low less than 65% (9, 34, and 19 patients, respectively). The best ScvO2 cutoff value associated with the mortality was considered the critical value of ScvO2. Acute physiology and chronic health evaluation (APACHE) II score severity, ICU, and hospital stay, and hospital mortality were reported.Results Sixty-two type 1 ARF patients with a mean age of 60±17.4 years were included. Seventy-nine percent patients had pneumonia. Mechanical ventilation was indicated in 77.4% of the patients with a mean duration of 6±3.6 days. The mean ScvO2 at day 0, 3, and 7 were 67.7±8.1, 66±11, and 69.3±9.3, respectively. The mean hospital stay was 6.8±4 days; 72.6% of the patients died in the hospital. Overall mortality in patients with low, normal, and high ScvO2 (at admission) were 42.2, 40, and 17.8%, respectively. Abnormal low and high ScvO2 was significantly related to mortality (P<0.0001). The cutoff point of ScvO2 at admission for mortality prediction was less than or equal to 65% (P=0.0008), 100 specificity, 49 sensitivity, 100 positive predictive value, and 42.5 negative predictive value. Mechanical ventilation, APACHE II score more than 27, development of complications, low initial arterial oxygen saturation and partial arterial oxygen pressure, the ScvO2 cutoff point less than or equal to 65% at admission, less than or equal to 70% at third and less than or equal to 66% at seventh day were significantly related to the mortality (<0.0001, <0.0001, <0.0001, 0.01, 0.03, 0.0008, 0.04 and 0.04, respectively).Conclusion In type1 ARF patients, abnormal low and high ScvO2 after day 0, 3, and 7, % of ScvO2 change in third and seventh day, and high APACHE II score were significantly linked to high mortality.Clinical implications In critically ill patients, ScvO2 is useful in the estimation of tissue oxygenation and may replace the use of mixed venous oxygen saturation.

Agreement of Central Venous Saturation and Mixed Venous Oxygen Saturation in Patients With Pulmonary Arterial Hypertension After Cardiac Surgery

Agreement of Central Venous Saturation and Mixed Venous Oxygen Saturation in Patients With Pulmonary Arterial Hypertension After Cardiac Surgery

Predictive Role of Central Venous Oxygen Saturation in Patients With Acute Type I Respiratory Failure

Predictive Role of Central Venous Oxygen Saturation in Patients With Acute Type I Respiratory Failure

165 - The Peripherally Inserted Central Catheter is a Reliable Tool to Obtain Venous Oxygen Saturation in Patients with Heart Failure

Background: For heart failure (HF) patients in the intensive care unit (ICU), venous oxygen saturations, which are used to calculate Fick cardiac output, are routinely measured from the distal port of the pulmonary artery catheter (PAC), which is typically in place to deliver inotropes. However, the PAC is not meant for long-term use and many patients require inotropes outside the ICU. The peripherally inserted central catheter (PICC) offers increased mobility, is intended for long-term use, and is used to deliver inotropes to patients outside of the ICU; yet, venous oxygen saturations are not currently measured via the PICC line. Objective: To determine if patients' oxygen saturation values differ between the PICC line and the distal Pulmonary artery (PA) and the proximal central venous pressure (CVP) ports on the PAC line. Methods: HF patients in the ICU were prospectively enrolled at the Baylor University Medical Center, Dallas, Texas. A total of 3 blood samples were taken per person (one sample at each PICC, CVP, and distal location). We performed repeated measures analysis of variance, as well as correlation and reliability analyses to assess the venous oxygen saturations. Results: There were 31 subjects included in the analysis; 77.4% were male, 71.0% were Caucasian, their mean (±standard deviation) age was 60.2 ± 8.46 years, and 80.0% received inotropes. The average oxygen saturation was 62.3 ± 10.7, 62.4 ± 11.7, and 61.4 ± 9.3 for the PICC line, CVP port, and distal port, respectively (PHuynh-Feldt = 0.66). The values from the PICC line had a strong, positive, linear correlation with those from the CVP and distal ports (r = 0.89, 0.76, respectively). Similarly, the correlation between the CVP and distal port was 0.72. The reliability of the values obtained across the 3 locations was excellent (Shrout-Fleiss reliability = 0.79). Conclusions: The venous oxygen saturation did not differ significantly between the PICC line, CVP port, or distal port, on average. Further, the majority (61.3%) of the patients' saturations differed by 5 or less percentage points between the PICC line and distal port of the PAC. This work indicates that reliable values of venous oxygen saturation may be obtained via the PICC line, after initial evaluation from the PAC. In turn, this may provide long-term hemodynamic assessment out of the ICU while improving patient comfort and mobility

Retinal oximetry during treatment of retinal vein occlusion by ranibizumab in patients with high blood pressure and dyslipidemia

In the present study, we examined retinal vascular oxygen saturation in patients with retinal vein occlusion (RVO), high blood pressure (HBP) and dyslipidemia, before and during intravitreal vascular endothelial growth factor (VEGF) injection (ranibizumab). We retrospectively reviewed the medical records of six patients with visual acuity (VA) reduced by macular edema (ME) secondary to RVO with HBP and dyslipidemia, who underwent intravitreal anti-VEGF injection between October 2014 and February 2015 in the department of ophthalmology of François-Quesnay Hospital at Mantes-la-Jolie (France). The main inclusion criterion was the presence of RVO with ME and decreased VA. The primary endpoint was improvement of retinal venous oxygen saturation in patients with RVO before and 3months after intravitreal ranibizumab injection. Secondary outcomes were improvement of retinal arterial oxygen saturation, improvement of best-corrected visual acuity (BCVA) on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, regression of ME measured by the central macular thickness (CMT) in nm and studying the correlation between blood pressure (BP) and retinal venous oxygen saturation before and after ranibizumab. Six eyes of six patients were included. Before treatment, the mean (standard deviation [SD]) of the retinal venous saturation (%) was 38.1±14.2. Three months after the injections, the mean (SD) of the retinal venous saturation (%) increased statistically significantly 49.2±11 (P=0.03). In this study, retinal venous oxygen saturation in patients with RVO, HBP and dyslipidemia was partially normalized during intravitreal ranibizumab treatment.

Comparison between mixed and central venous oxygen saturation in patients with severe acute heart failure after cardiac surgery: A prospective observational study

[1] Maron BJ, Towbin JA, Thiene G, et al. Contemporary definitions and classification ofthe cardiomyopathies.An American Heart Associationscientific statementfromtheCouncil on Clinical Cardiology, Heart Failure and Transplantation Committee;Quality of Care and Outcomes Research and Functional Genomics and TranslationalBiology Interdisciplinary Working Groups; and Council on Epidemiology andPrevention. Circulation April 2006;113(14):1807–16.[2] Elliott P, Andersson B, Arbustini E, et al. Classification of the cardiomyopathies: aposition statement from the European Society Of Cardiology Working Group onMyocardial and Pericardial Diseases. Eur Heart J Jan 2008;29(2):270–6.0167-5273/$ – see front matter © 2014 Elsevier Ireland Ltd. All rights reserved.http://dx.doi.org/10.1016/j.ijcard.2014.05.038

Comparison of the effect of fluid resuscitation as guided either by lactate clearance rate or by central venous oxygen saturation in patients with sepsis

To compare the efficacy of fluid resuscitation as guided by lactate clearance rate (LCR) and central venous oxygen saturation (ScvO2) in patients with sepsis. A prospective randomized control study was conducted. Fifty patients diagnosed with severe sepsis or septic shock from January 2011 to February 2012 in department of critical care medicine of Fourth Hospital of Hebei Medical University were enrolled in the study. The patients were randomly divided into two groups according to the sequence (each n=25): ScvO2 group and LCR group. After ICU admission, the patients were treated symptomatically timely, and fluid resuscitation was started as early as possible according to Surviving Sepsis Campaign guidance for management of severe sepsis and septic shock 2008. Central venous pressure (CVP)≥8 mm Hg (1 mm Hg=0.133 kPa), mean arterial pressure (MAP)≥65 mm Hg and ScvO2≥0.70 served as goal values to accomplish the fluid resuscitation therapy in ScvO2 group, while CVP≥8 mm Hg, MAP≥65 mm Hg, LCR≥10% served as goal value to accomplish the fluid resuscitation therapy in LCR group. The general condition and clinical characteristics on arrival in ICU, changes in CVP, MAP, ScvO2, lactate level and/or LCR before (0 hour) and 3, 6, 72 hours after the start of fluid resuscitation and the other related conditions during the therapy were recorded. There was no significant difference in general data or clinical characteristics before the start of therapy, occurrence of organ dysfunction, or treatment measures during different time periods after start of fluid resuscitation. Compared with the condition immediately before fluid resuscitation, at 3 hours after start of fluid resuscitation, CVP were improved in LCR and ScvO2 groups (8.58±1.17 mm Hg vs. 6.33±1.21 mm Hg, 9.08±2.43 mm Hg vs. 5.33±0.98 mm Hg, both P<0.05); at 6 hours after start of fluid resuscitation, heart rate (HR) and respiratory rate (RR) were lowered in LCR and ScvO2 groups (HR: 96±18 bpm vs. 127±13 bpm, 98±13 bpm vs. 116±19 bpm, RR: 23±3 times/min vs. 33±9 times/min, 24±5 times/min vs. 35±6 times/min, all P<0.05), oxygenation index (PaO2/FiO2) was increased in LCR and ScvO2 groups (179±41 mm Hg vs. 86±21 mm Hg, 202±33 mm Hg vs. 95±17 mm Hg, both P<0.05), and there was no significant difference in MAP in both groups. There was no significant difference in all indexes between two groups. In LCR group, 3 hours after start of fluid resuscitation, lactate level was significantly decreased (2.81±0.18 mmol/L vs. 3.43±1.31 mmol/L, P<0.05). Compared with the value 3 hours after start of fluid resuscitation, LCR was significantly improved at 6 hours and 72 hours after start of fluid resuscitation in LCR group [(42.69±8.75)%, (48.87±9.69)% vs. (20.32±4.58)%, both P<0.05]. Compared with that immediately before fluid resuscitation, ScvO2 was significant improved in ScvO2 group at 3 hours after start of fluid resuscitation (0.65±0.04 vs. 0.53±0.06, P<0.05). There was no significant difference in success rate of fluid resuscitation comparing that of 6 hours and that of 72 hours [6 hours: 72% (18/25) vs. 64% (16/25), χ(2)=0.368, P=0.762; 72 hours: 88% (22/25) vs. 88% (22/25) ,χ(2)=0.000, P=1.000], length of ICU stay (8±3 days vs. 10±4 days, t=0.533, P=0.874), length of hospital stay (29±11 days vs. 35±16 days, t=0.692, P=0.531), improvement rate [84% (21/25) vs. 76%(19/25), χ(2)=0.500, P=0.480] or 28-day mortality [20% (5/25) vs. 28% (7/25), χ(2)=0.439, P=0.742] between LCR and ScvO2 groups. Both LCR and ScvO2 can be taken as the index in confirming the endpoint of fluid resuscitation for patients with severe sepsis and septic shock. Fluid resuscitation therapy under the guidance of LCR is accurate and reliable in patients with severe sepsis and septic shock.

Phenylephrine 5% added to Tropicamide 0.5% eye drops does not influence retinal oxygen saturation values or retinal vessel diameter in glaucoma patients

To test whether adding topical phenylephrine 5% to tropicamide 0.5% eye drops in the protocol for pupil dilation affects the retinal vessel oximeter measurements in patients with glaucoma. To test whether phenylephrine 5% has an influence as a vasoconstrictor on the retinal vessel width and can improve the proportion of high-quality retinal images in patients with glaucoma. Retinal images of 66 patients with chronic open-angle glaucoma were obtained before and after the administration of phenylephrine 5% eye drops to patients already dilated with tropicamide 0.5% with the Oxymap Retinal Oximeter (Oxymap ehf, Reykjavik, Iceland). Specialized software, Oxymap Analyzer, analysed the images and measured the oxygen saturation and vessel diameter. Oxygen saturation was measured in first- and second-degree vessels. A Mann-Whitney U-test was used to compare both groups. Quality of the images was assessed, and a Fisher's exact test was used to compare the proportion of high- and poor-quality images. There was no significant difference in arterial and venous oxygen saturation in patients with glaucoma whether dilated by tropicamide alone or a combination of tropicamide and phenylephrine (97 ± 6% versus 96 ± 5%, p = 0.88 for arterial saturation and 66 ± 6% versus 67 ± 6%, p = 0.78 for venous saturation, n = 27). There was no significant difference in vessel diameter between both conditions for the different vessels (p = 0.61 for arterial saturation and p = 0.51 for venous saturation, n = 27). The proportion of high-quality images was significantly higher after the combination regimen compared with tropicamide only (p = 0.0001). The addition of topical phenylephrine 5% after tropicamide 0.5% improved the proportion of high-quality retinal oximetry images without influencing the retinal oxygen saturation values or the retinal vessel diameter in patients with glaucoma.

Choroidal blood flow in central serous chorioretinopathy (CSC)

AbstractPurpose Central serous chorioretinopathy (CSC) has been linked to alterations in perfusion and metabolism. In the present study we investigated arterial and venous oxygen saturation in patients with active CSC and compared it to the data in healthy subjects.Methods A total of 13 subjects with active CSC and 13 healthy age‐ and sex‐matched control subjects were included in this study. Retinal arterial and venous oxygen saturation was measured in an annular area centered at the optic disk using the Imedos Oxygen Module for the Retinal Vessel Analyzer (RVA).Results No significant difference was observed between the patients with CCS and healthy control subjects. This was the case for retinal arterial oxygen saturation (95.0 ± 4.5 % in patients with CCS, 96.2 ± 4.2 %; p = 0.463) and for retinal venous oxygen saturation (66.6 ± 5.5 % in patients with CCS, 63.7 ± 6.1 %; p = 0.392).Conclusion Previous studies have shown that CSC is associated with abnormalities in choroidal blood flow regulation. Our data indicate, however, that retinal oxygenation is normal in CSC patients during the active phase.

Changes in plasma phenylalanine, isoleucine, leucine, and valine are associated with significant changes in intracranial pressure and jugular venous oxygen saturation in patients with severe traumatic brain injury

Changes in plasma aromatic amino acids (AAA=phenylalanine, tryptophan, tyrosine) and branched chain amino acids (BCAA=isoleucine, leucine, valine) levels possibly influencing intracranial pressure (ICP) and cerebral oxygen consumption (SjvO(2)) were investigated in 19 sedated patients up to 14days following severe traumatic brain injury (TBI). Compared to 44 healthy volunteers, jugular venous plasma BCAA were significantly decreased by 35% (p<0.001) while AAA were markedly increased in TBI patients by 19% (p<0.001). The BCAA to AAA ratio was significantly decreased by 55% (p<0.001) which persisted during the entire study period. Elevated plasma phenylalanine was associated with decreased ICP and increased SjvO(2), while higher plasma isoleucine and leucine levels were associated with increased ICP and higher plasma leucine and valine were linked to decreased SjvO(2). The amount of enterally administered amino acids was associated with significantly increased plasma levels with the exception of phenylalanine. Contrary to the initial assumption that elevated AAA and decreased BCAA levels are detrimental, increased plasma phenylalanine levels were associated with beneficial signs in terms of decreased ICP and reduced cerebral oxygen consumption reflected by increased SjvO(2); concomitantly, elevated plasma isoleucine and leucine levels were associated with increased ICP while leucine and valine were associated with decreased SjvO(2) following severe TBI, respectively. The impact of enteral nutrition on this observed pattern must be examined prospectively to determine if higher amounts of phenylalanine should be administered to promote beneficial effects on brain metabolism and if normalization of plasma BCAA levels is without cerebral side effects.

Masseter muscle oxygen saturation is associated with central venous oxygen saturation in patients with severe sepsis

This monocentric prospective study was conducted to determine if tissue oxygen saturation measured non invasively over masseter muscle site (Masseter-StO2) can predict the central venous oxygen saturation (ScvO2) level in severe sepsis and septic shock. Sixteen consecutive patients with severe sepsis (n = 10) or septic shock (n = 6) were included in this study. ScvO2 was measured on blood samples taken from the superior vena cava via the distal line of a central venous catheter. Masseter-StO2 was measured with a 25 mm depth infrared probe, applied and attached to the skin using transparent adhesive shields. Fifty-seven pairs of measures were obtained. Mean ScvO2 was 76.5% (median 81, standard deviation 15, range [14-94]). Twenty percent of the ScvO2 measures were lower than 70%. Seven out of 16 patients had at least one measure of 70% or less. Mean Masseter-StO2 was 81% (median 91, standard deviation 18, range [29-98]). We found a significant association between ScvO2 and Masseter-StO2 (correlation coefficient 0.65, P < 0.01), however agreement was moderate. In patients with severe sepsis or septic shock, non invasive recording of Masseter-StO2 was significantly associated with ScvO2 Further studies are required to determine the usefulness of Masseter-StO2 guided management of severe sepsis or septic shock.

The importance of low central venous oxygen saturation levels in patients after cardiac surgery

Objectives: Reduced venous oxygen saturation reflect global tissue hypoxia. This has been associated with increased risk of morbidity and mortality. This observation was started to characterize low central venous oxygen saturation in patients after cardiac surgery.

Mixed venous versus central venous oxygen saturation in patients undergoing on pump beating coronary artery bypass grafting.

Objective:To examine the validity of central venous oxygen saturation (ScvO2) as a numerical substitution of mixed venous oxygen saturation (SvO2) in adult patients undergoing normothermic on pump beating coronary artery bypass grafting (CABG).Materials and Methods:Prospective clinical observational study was done at King Khalid University Hospital, King Saud University, Riyadh, Kingdom of Saudi Arabia. Thirty four adult patients scheduled for coronary artery surgery were included. Patients were monitored by a pulmonary artery catheter (PAC) as a part of our routine intraoperative monitoring. SvO2 and ScvO2 were simultaneously measured 15 minutes (T1) and 30 minutes (T2) after induction of anesthesia, 15 and 30 minutes after initiation of cardiopulmonary bypass (T3 and T4), and 15 and 30 minutes after admission to intensive care unit (T5 and T6).Results:ScvO2 showed higher reading than SvO2 all through our study. Our results showed perfect positive statistically significant correlation between SvO2 and ScvO2 at all data points. Individual mean of difference (MOD) between both the readings at study time showed MOD of 1.34 and 1.44 at T1 and T2 simultaneously. This MOD was statistically insignificant, but after on pump beating normothermic bypass was initiated; MOD was 5.2 and 4.4 at T3 and T4 with high statistical significance. In ICU, MOD continues to have high statistical significance, MOD was 6.3 at T5 and at T6 it was 4.6.Conclusions:In on pump beating CABG patients; ScvO2 and SvO2 are not interchangeable numerically. ScvO2 is useful in the meaning of trend; our data suggest that ScvO2 is equivalent to SvO2 , only in the course of clinical decisions as long as absolute values are not required.

A Comparison of Mixed and Central Venous Oxygen Saturation in Patients during and after Cardiac Surgery

Monitoring of mixed venous oxygen saturation (Sv̄O2) allows assessment of the global balance between oxygen supply and demand. Sv̄O2 measurement requires the insertion of a pulmonary artery catheter (PAC) whereas central venous oxygen saturation (ScvO2) monitoring only requires a central venous catheter. The aim of this study was to assess how continuous measurements of ScvO2 relate to simultaneous measurements of Sv̄O2 during and after cardiac surgery. Continuous Sv̄O2 and ScvO2 measurements in 15 patients undergoing elective cardiac surgery were recorded each minute for 24 hours. Bland-Altman analysis of 9,382 paired data points for Sv̄O2 and ScvO2 revealed a mean bias of 4.4% (95% Cl +22.3, −13.6%). Considerable inter- and intra-individual variability was noted. Based on these data and previous studies, ScvO2 and Sv̄O2 are not interchangeable variables.

The value of central venous oxygen saturation in patients with implanted biventricular assist device

The value of central venous oxygen saturation in patients with implanted biventricular assist device

A Comparison of Central and Mixed Venous Oxygen Saturation in Circulatory Failure

The purpose of this study was to evaluate whether central venous oxygen saturation can be used as an alternative to mixed venous oxygen saturation in patients with cardiogenic and septic shock. Prospective clinical study. A tertiary intensive care unit in a university hospital. Twenty patients with cardiogenic or septic shock requiring a pulmonary artery catheter and inotropic support. None. The central venous oxygen saturation overestimated the mixed venous oxygen saturation by a mean bias (or an absolute difference) of 6.9%, and the 95% limits of agreement were large (-5.0% to 18.8%). The difference between central and mixed venous oxygen saturation appeared to be more significant when mixed venous oxygen saturation was <70%. The changes in central and mixed venous oxygen saturation did not follow the line of perfect agreement closely in different clinical conditions. The central or mixed venous oxygen saturation had a significant ability to predict the status of cardiac output state, but this ability was reduced when the effect of hyperoxia was not considered. Central and mixed venous oxygen saturation measurements are not interchangeable numerically.

Comparison between Regional Cerebral Oxygen Saturation and Jugular Bulb Venous Oxygen Saturation in Patients Undergoing OPCAB Surgery

Background: Hypoperfusion during manipulation of the heart in off-pump coronary artery bypass (OPCAB) surgery may lead to postoperative neurological complications. Therefore, it will be necessary to monitor cerebral function during OPCAB surgery. In this study, we compared regional cerebral oxygenation (rSO2) by near-infrared spectroscopy (NIRS) with jugular bulb venous oxygen saturation (SjvO2) and assessed whether rSO2 measured by NIRS could be an alternative method of SjvO2 during OPCAB surgery. Methods: A total of 20 patients who underwent OPCAB surgery were studied. A fiberoptic catheter was placed in the right jugular bulb to measure SjvO2 while a cerebral oximeter based on NIRS, INVOS 5100B was used to monitor rSO2. Radial arterial and jugular bulb blood samples were drawn simultaneously from baseline every hour during operation. The values of rSO2 were compared with SjvO2 values. Results: For all data points (n = 78) for all patients combined, rSO2 values were significantly correlated with SjvO2 values (r = 0.513, P ＜ 0.0001). There were significant correlations between arterial carbon dioxide and values of SjvO2 (r = 0.393, P = 0.0002) and rSO2 (r = 0.432, P ＜ 0.0001). Conclusions: We concluded that NIRS correlates with SjvO2 in this patient population. These findings suggest that near-infrared spectroscopy may be useful in assessing cerebral oxygenation during OPCAB surgery. (Korean J Anesthesiol 2008; 54: 47～52)

Comparison of Central Venous to Mixed Venous Oxygen Saturation in Patients With Low Cardiac Index and Filling Pressures After Coronary Artery Surgery

To evaluate the correlation and agreement between mixed venous oxygen saturation (SvO(2)) and central venous oxygen saturation (ScvO(2)) in patients with low cardiac index and filling pressures after coronary artery surgery. Prospective observational study. Tertiary care academic hospital. Sixty consecutive patients with a cardiac index <2 L/min/m(2) and a pulmonary artery occlusion pressure <12 mmHg after coronary artery surgery were included. Patients were monitored by a pulmonary artery catheter and a central venous catheter positioned in the superior vena cava. SvO(2) and ScvO(2) were simultaneously measured before (T0) and after (T1) normalization of the cardiac index (>2.5 L/min/m(2)) by fluid therapy. Sixty pairs of measures were obtained at T0 and at T1. Bias between SvO(2) and ScvO(2) was -0.6% (T0) and -0.8% (T1). Limits of agreement were from -19.2% to 18% (T0) and from -15.6% to 14% (T1), and the correlation coefficient was 0.463 (T0) and 0.72 (T1). SvO(2) and ScvO(2) changes from T0 to T1 (DeltaSvO(2) and DeltaScvO(2)) were calculated. The bias between DeltaSvO(2) and DeltaScvO(2) was -0.25. Limits of agreement were from -20% to 19.5%, and the correlation coefficient was 0.6. In patients with low cardiac index and filling pressures after coronary artery surgery, ScvO(2) could not be used as a direct alternative for SvO(2). After fluid therapy and normalization of the cardiac index, differences between individual values remained large, and the disagreement between ScvO(2) and SvO(2) changes was significant.