Measurement Of ScvO2 Research Articles

Prognostic value of combined central venous oxygen saturation and lactate in pediatric patients after cardiac surgery

ObjectivesThis study assessed the value of measuring both arterial lactate levels and central venous oxygen saturation (ScvO2) in predicting cardiac surgery outcomes in pediatric patients.MethodsA prospective cohort study was conducted on 73 patients who underwent surgery for congenital heart disease. Vasoactive-inotropic score (VIS), serial mean arterial blood pressures (MAP), lactate levels, and ScvO2 were measured immediately and 3, 6, 12, 18, and 24 h after admission to the pediatric intensive care unit (PICU). To test the prognostic values of these markers, we calculated the areas under the receiver operating characteristic curves (AUCs). Binary logistic regression was used to identify the determinants of postsurgical complications.ResultsThe most common complications after cardiac surgery were the prolonged need for mechanical ventilation (38.36%), chest infection (30.14%), prolonged stay in the PICU (24.66%), and sepsis (9.59%). ScvO2 6 h after admission was most predictive of complications (AUC = 85.5%), followed by ScvO2/lactate (AUC = 83.0%), lactate level 12 h after admission (AUC = 75.0%), MAP (AUC = 73.6%), and VIS (AUC = 63.4). In multivariate analysis, body weight and ScvO2 6 h after PICU admission were the main predictors of complications (OR = 0.01, 95% CI 0.001–0.689, p = 0.033), and (OR = 0.87, 95% CI 0.798–0.948, p = 0.002) respectively.ConclusionsTo predict complications after pediatric cardiac surgery, lactate measurement does not add value to ScvO2 measurement 6 h after admission.The Cochrane TRNPACTR202104905893217.Date of registration 12 April 2021.

Oxygen Extraction and Mortality in Patients Undergoing Chronic Haemodialysis Treatment: A Multicentre Study.

Patients on haemodialysis (HD) suffer a high mortality rate linked to developing subclinical hypoxic parenchymal stress during HD sessions. The oxygen extraction ratio (OER), an estimate of the oxygen claimed by peripheral tissues, might represent a new prognostic factor in HD patients. This study evaluated whether the intradialytic change in OER (ΔOER) identified patients with higher mortality risks. We enrolled chronic HD patients with permanent central venous catheters with available central venous oxygen saturation (ScvO2) measurements; the arterial oxygen saturation was measured with peripheral oximeters (SpO2). We measured OER before and after HD at enrolment; deaths were recorded during two-years of follow-up. In 101 patients (age: 72.9 ± 13.6 years, HD vintage: 9.6 ± 16.6 years), 44 deaths were recorded during 11.6 ± 7.5 months of follow-up. Patients were divided into two groups according to a 40% ΔOER threshold (ΔOER < 40%, n = 56; ΔOER ≥ 40%, n = 45). The ΔOER ≥ 40% group showed a higher incidence of death (60% vs. 30%; p = 0.005). The survival curve (log-rank-test: p = 0.0001) and multivariate analysis (p = 0.0002) confirmed a ΔOER ≥ 40% as a mortality risk factor. This study showed the intradialytic ΔOER ≥ 40% was a mortality risk factor able to highlight critical hypoxic damage. Using a ΔOER ≥ 40% could be clinically applicable to characterise the most fragile patients.

MO786: Monitoring of Arterio-Venous Fistula Maturation using Central-Venous Oxygen Saturation and Estimated Upper-Body Blood Flow: Impact on Catheter Residence Time

Abstract BACKGROUND AND AIMS In hemodialysis patients, assessment of arterio-venous fistula (AVF) maturation is key to reduce the residence time of central venous catheters (CVC). We have introduced the use of central-venous oxygen saturation (ScvO2) and estimated upper-body blood flow (eUBBF) as means to monitor AVF maturation [1]. We now report CVC residence time in patients with and without ScvO2-based AVF maturation monitoring. METHOD We studied hemodialysis patients in who ScvO2-based AVF maturation monitoring was implemented within the framework of a clinical quality improvement project (QIP). ScvO2 and hematocrit were measured with Crit-Line (Fresenius Medical Care, Waltham, MA). eUBBF was computed as described previously [1]. We used time-to-event analysis to compare the CVC residence time post-AVF creation between patients who participated in the QIP (intervention group) and non-QIP patients (control group). Both groups were dialyzed in the same geography. Patients were censored at the time of death, change of dialytic modality, transplantation, lost to follow up, recovery of kidney function and end of the observation period (15 November 2021). RESULTS The intervention group comprised 44 patients [age 57 ± 17 years; 27 (61%) males]. In five patients, two AVF were created; in 34 (69%) CVC were removed. The control group comprised of 378 patients (age 59 ± 15 years, 61% males). CVC was removed in 199 (53%) control patients. In the intervention group, CVC were removed 125 days [95% confidence interval (95% CI): 102–171] after AVF creation. In the control group, this time was 236 days (95% CI: 173–404) (P &amp;lt; 0.0003; log rank test; Figure). CONCLUSION Compared to controls, the CVC residence time post AVF-creation was shortened significantly— by about 3.6 months—in patients who participated in a QIP that used ScvO2-baseed assessment of AVF maturation. Measurement of ScvO2 and computation of eUBBF are simple, non-invasive means to track AVF maturation, trigger timely interventions and AVF cannulation and shorten CVC residence time.

Correlation Between Venous Oxygen Saturations Obtained From Pulmonary Artery Catheter And Peripherally Inserted Central Catheter In Patients Receiving Inotrope Support

Correlation Between Venous Oxygen Saturations Obtained From Pulmonary Artery Catheter And Peripherally Inserted Central Catheter In Patients Receiving Inotrope Support

Accuracy, Precision, and Trending Ability of Perioperative Central Venous Oxygen Saturation Compared to Mixed Venous Oxygen Saturation in Unselected Cardiac Surgical Patients

To determine whether central venous oxygen saturation (ScvO2) measurements could be used interchangeably with mixed venous oxygen saturation (SvO2) measurements in adult cardiac surgery patients. A single-center prospective observational study. A university hospital. Eighty-five adult patients undergoing cardiac surgery. The study authors compared the oxygen saturations in 590 pairs of venous blood samples drawn from the pulmonary artery catheter (PAC) at three different time points during surgery and four different time points in the intensive care unit. They compared samples obtained from the distal pulmonary artery line (SvO2) to those drawn from the proximal central venous line of the PAC (ScvO2) with the Bland-Altman test and the four-quadrant method. The mean bias between SvO2 and ScvO2 was -1.9 (95% confidence interval [CI], -2.3 to -1.5) and the limits of agreement (LOA) were -11.5 to 7.6 (95% CI, -12.5 to -10.7 and 6.8-8.5, respectively). The percentage error (PE) was 13.2%. Based on the four-quadrant plot, only 50% of the measurement pairs were in agreement, indicating deficient trending ability. ScvO2 values showed acceptable accuracy as the mean bias was low. The precision was inadequate; although the PE was acceptable, the LOA were wide. Trending ability was inadequate. The authors cannot recommend the use of ScvO2 values interchangeably with SvO2 measurements in the management of adult cardiac surgery patients.

MO821OXYGEN EXTRACTION RATIO AND MORTALITY RISK IN HAEMODIALYSIS PATIENT: A MULTICENTRE STUDY

Abstract Background and Aims Patients on haemodialysis (HD) suffer a very high rate of cardiovascular mortality with some evidence suggesting a possible association with decreasing blood oxygen saturation (SO2) during sessions. The ratio between arterial SO2 (SaO2) and central venous SO2 (ScvO2) or Oxygen Extraction Ratio (OER), which represents an estimate of the amount of oxygen claimed by peripheral tissues and of the haemodialysis related hypoxic stress, might represent a new prognostic factor. Method We evaluate the relationship between OER values and mortality risks in HD patients in a prospective multicentre observational study. We enrolled chronic HD patients with permanent central venous catheter (CVC) and no fistula, in whom ScvO2 measurement is at hand and SaO2 is available with a peripheral oxymeter. OER ([(SaO2−ScvO2)/SaO2]×100) was measured before and after HD at enrolment (HD OER sessions) in each patients, and a one-year follow-up was planned to record the number of deaths. Results In 101 patients (age 71.5 ± 14 years on dialysis for 47 ± 38 months), during 9 ± 6 months of follow up, we recorded 35 deaths. Patients were then divided into two groups, above or below the median value of pre-HD OER, which was 30%. In these groups, the average incidence of deaths was 12% (24 deaths) and 5,5% (11 deaths) respectively (p&amp;lt;0.05), with significantly different survival curves (Kaplan-Meier log rank test = 0.04, fig). No difference in mortality was evident if we divided patients according to the median intradialytic change in OER value. Conclusion Patients with pre-HD OER &amp;gt; 30% have a higher mortality risk, most probably secondary to reduced capability to respond to HD related oxygen requirements. OER is novel biomarker to identify patients at greatest clinical risk.

Analysis of structure indicators influencing 3-h and 6-h compliance with the surviving sepsis campaign guidelines in China: a systematic review

BackgroundCompliance with the surviving sepsis campaign (SSC) guidelines (Cssc) is a key factor affecting the effects of sepsis treatment. We designed this study to investigate the relationships of the structure indicators of ICU on 3 and 6-h Cssc in China.MethodsA total of 1854 hospitals were enrolled in a survey, led by the China National Critical Care Quality Control Center (China-NCCQC) from January 1, 2018, through December 31, 2018. We investigated the 1854 hospitals’ 3 and 6-h Cssc, including compliance with each specific measure of the 3-h and 6-h SSC bundles. We also investigated the actual level of the structure indicators of ICU, released by China-NCCQC in 2015.The outcomes were in adherence with the SSC guidelines (2016). Monitoring indicators included 3 and 6-h Cssc.ResultsIn the subgroup, the rate of broad-spectrum antibiotic therapy was the highest, and the rate of CVP and ScvO2 measurement was the lowest among the items of 3 and 6-h Cssc. Structure indicators related to 3 and 6-h Cssc include the predicted mortality rate and the standardized mortality ratio (SMR). The relationships between 3 and 6-h Cssc and the proportion of ICU in total inpatient bed occupancy, the proportion of acute physiology and chronic health evaluation (APACHE) II score ≥ 15 in all ICU patients were uncertain. There was no relationship of 3 and 6-h Cssc with the proportion of ICU patients among total inpatients.ConclusionsStructure indicators influencing 3 and 6-h Cssc in China are the predicted mortality rate and the standardized mortality rate.

Oxygen extraction ratio to identify patients at increased risk of intradialytic hypotension

Intradialytic hypotension (IDH) is a hemodynamic phenomenon recently associated with decreased blood oxygen saturation (SO2). The ratio between peripheral oxygen saturation (SpO2) and central venous SO2 (ScvO2) or Oxygen Extraction Ratio (OER), which represents a roughly estimate of the amount of oxygen claimed by peripheral tissues, might be used to estimate haemodialysis (HD) related hypoxic stress. Aim of this pilot study was to evaluate the relationship between OER increments during dialysis sessions (ΔOER) and episodes of IDH. We enrolled chronic HD patients with permanent central venous catheter (CVC) and no fistula, in whom ScvO2 measurement is at hand. OER ([(SpO2 − ScvO2)/SpO2] × 100) was measured in three consecutive HD sessions (HD OER sessions) before HD, after 15′, 30′ and 60′ min and at the end of HD. Then, a one-year follow-up was planned to record the number of IDH episodes. In the 28 enrolled patients (age 74 ± 2.6 years), during 12 ± 1.2 months of follow up, incidence of IDH was 3.6%. We divided patients into two groups, above or below the median value of ΔOER at the end of HD, which was 36%. In these groups, the average incidence of IDH was 7% and 2% respectively (p < 0.01), while OER values before HD were not different. Notably, in the high ΔOER group the OER increment was evident since after 15′ and was significantly higher than in the low ∆OER group (∆OER-15′ = 19 ± 3.0% vs. 9.0 ± 3.0%; p < 0.05). By comparison, blood volume changes overlapped in the two groups (average change − 9 ± 0.8%). Values of ∆OER > 19% after only 15′ of HD treatment or > 36% at the end of the session characterize patients with higher rates of hypotension. Intradialytic ∆OER, a parameter of tissue hypoxic stress, identifies more fragile patients at greater risk of IDH.

Noninvasive monitoring of central venous oxygen saturation by jugular transcutaneous near-infrared spectroscopy in pediatric patients undergoing congenital cardiac surgery

Background and aimIn patients undergoing congenital cardiac surgery, it is crucial to maintain oxygen demand-consumption balance. Central venous oxygen saturation (ScvO2) is a useful indicator of oxygen demand and consumption balance which is an invasive method. Near-infrared spectroscopy (NIRS) is a noninvasive, continuous monitoring technique that measures regional tissue oxygenation. NIRS that is placed over the internal jugular vein cutaneous area (NIRSijv) has the potential to show ScvO2 indirectly. In this study, we aimed to determine the correlation between ScvO2 with NIRSijv in pediatric patients undergoing congenital cardiac surgery.Materials and methodsFifty children participated in the study. Four patients were excluded for the inability of internal jugular vein (IJV) catheterization due to technical difficulties. After anesthesia induction, NIRS probes were placed on the IJV site with ultrasound guidance for the measurement of continuous transcutaneous oxygen saturation. The catheter insertion was also done through the IJV from the other side using ultrasound guidance. Cerebral oxygenation monitoring was done using NIRS with a single pediatric probe placed on the right forehead. Values of NIRSijv, cerebral NIRS (NIRSc) and ScvO2, were recorded at certain times until postoperative 24th hour.ResultsData were collected at 8 different time points. There was a significant correlation between ScvO2 and NIRSijv in all measurement time points (r = 0.91), (P = 0.001). The mean bias between ScvO2 and NIRSijv was 2.92% and the limits of agreement were from 11% to –5.2%. There was a moderate correlation between ScvO2 and NIRSc (r = 0.45), (P = 0.001). The mean bias between ScvO2 and NIRSc was 2.7% and the limits of agreement were from +26% to –20%.ConclusionIn this study, we found a strong correlation between ScvO2 and NIRS measurements taken from the internal jugular vein site. Accordingly, continuous noninvasive monitoring with transcutaneous NIRSijv can be an alternative method as a trend monitor for the central venous oxygen saturation in pediatric cardiac patients undergoing congenital cardiac surgery.

Serum lactate poorly predicts central venous oxygen saturation in critically ill patients: a retrospective cohort study

BackgroundSerum lactate and central venous oxygen saturation (ScvO2) are commonly used and commonly recommended as markers of tissue oxygenation in shock states. Medical literature has both explicitly stated and implied that the two biomarkers are interchangeable in the management of patients with shock. However, there have been relatively few direct comparisons of these tests in clinical circumstances, and the relationship between them is uncertain. The objective of our study was to evaluate whether simultaneous or near-simultaneous measurements of lactate and ScvO2 reveal a consistent relationship between these two biomarkers.MethodsA retrospective cohort study was conducted in an urban, academic US hospital. All adults in ICUs between March 2007 and March 2017 who had a lactate measurement and ScvO2 or mixed venous oxygen saturation (SvO2) measurement made +/− 1 h from the lactate were included. Linear and non-linear correlations of ScvO2 and lactate were assessed in a variety of shock states.ResultsTwo thousand sixty-two patients were included. Lactate and ScvO2 correlated poorly (r2 = 0.0041, p = 0.0019). This was true for patients with ScvO2 ≤ 65% (r2 = 0.0431, p < 0.001), patients with normal kidney and liver function (r2 = 0.0517, p < 0.001), and septic shock patients (r2 = 0.0037, p = 0.17). For patients with an O2 extraction ratio ≥ 50%, lactate and ScvO2 were strongly correlated (r2 = 0.93, p = 0.0019), but these patients represented only 2.8% of patients in whom the ratio could be calculated.ConclusionsLactate can predict ScvO2 when patients are at or below the critical oxygen delivery threshold, but relatively few shock patients meet this criterion. In the overall population of critically ill patients, serum lactate predicts ScvO2 poorly, even after controlling for factors that may affect lactate production. Lactate and ScvO2 should not be assumed to be interchangeable markers of tissue oxygenation/perfusion.

Does High Ultrafiltration Volume Correlate to Occurrence of Desaturation in Patients Undergoing Hemodialysis?

Background: Hemodialysis is a metabolically stressful condition for patients that leads to reduced oxygen saturation and tissue perfusion. One of the identified drivers is a high ultrafiltration volume (UFV). Concurrently, central venous oxygen saturation (ScvO2) is a marker for global tissue hypoxia that has been used in cases of sepsis and trauma to guide fluid therapy. In dialysis patients with a central venous catheter (CVC) access ScvO2 is accessible. Here we intend to delineate the relationship of UFV to desaturation during dialysis through the measurement of ScvO2. Methods: PICO was formulated from a clinical case, and a literature search was conducted in Pubmed, Embase, Scopus, and Cochrane. Selected studies were then critically appraised using harm/etiology worksheet from CEBM1 for validity, importance, and applicability. Results: Studies by Harrison, et al., Zhang, et al. and Rotondi, et al. were chosen for answering our PICO. Harrison, et al. reported a relation of r: -0.680, p:0.015 between UFV and ScvO2. While, Zhang, et al. utilized retrospective data of Critline Monitor (CLM) reading of dialysis patients and reported a negative 0.3% slope of ScvO2 over corrected UFV (cUFV). Whilst, Rotondi, et al. demonstrated that in 20 patients separated equally to exclusively dialysis or ultrafiltration and both caused lowering of ScvO2, but only the former was statistically significant. Discussion: The mechanism of relationship may include incapability of plasma refill rate to compensate for the fluid shift during ultrafiltration, resulting in lower cardiac preload and stroke volume which is detrimental in patients who are natively prone to suffer from reflex bradycardia and intradialytic hypotension. Studies have shown that episodes of hypoxemia in dialysis patients translate to worse prognosis. Conclusion: ScvO2 is inversely proportional to UFV. As such, monitoring for ScvO2 in dialysis patients will be beneficial to prevent end-organ ischemia.

Role of central venous oxygen saturation in prognostication of patients with severe sepsis and septic shock in emergency medical services.

Introduction:All the components of early goal-directed therapy, especially central venous oxygen saturation (ScvO2) as one of the endpoints of resuscitation, may not have mortality benefit, more so after results of the Australasian Resuscitation of Sepsis Evaluation, A Randomized Trial of Protocol-Based Care for Early Septic Shock, and The Protocolised Management in Sepsis trials. However, extrapolating results from trials undertaken in the developed world may not be entirely appropriate.Materials and Methods:In this prospective observational study conducted in the emergency medical services, we aimed to find out the mean baseline ScvO2 in a cohort of 200 patients presenting with severe sepsis/septic shock and its prognostic significance. The measurement of ScvO2 was performed by sampling blood from the superior vena cava through the central venous catheter.Results:The mean age of patients was 46.70 ± 17.64 years. The mean ScvO2 at baseline of the study cohort was 65.95 ± 20.70%. Based on initial ScvO2 values, 104 (52%) patients had a lower ScvO2 level, a priori classified as the hypoxic group. Sixty-five (32.5%) patients had an initial ScvO2 level in between 70 and 89%, categorized as normoxic group, and the remaining 31 (15.5%) patients had high ScvO2, leveled as the hyperoxic group. Sixty-six (33%) patients had hospital mortality. Of 104 hypoxemic patients, 28 (26.9%) had hospital mortality. In this group, the mean ScvO2 value in 28 nonsurvivors at baseline and after 6 h of resuscitation was 46.21 ±16.66% and 48.82 ±18.81%, respectively. Twenty-five (38.5%) patients had hospital mortality among 65 patients with baseline ScvO2 value in the normoxic range. Hospital mortality figure stood at 13 (41.9%) patients in the hyperoxic group. Among patients in the hyperoxic group, the mean serum lactate value at baseline in nonsurvivors was 4.52 ± 2.95 mmol/L, significantly higher as compared to the mean value of 2.89 ± 1.55 mmol/L in survivors. The hyperoxia group had higher hospital mortality though it was not statistically significant.Conclusion:The mean baseline ScvO2 was lower in our study cohort. In the hypoxic group, patients with hospital mortality had persistently lower ScvO2 level during the first 6 h of resuscitation. Importantly, higher mortality in the hyperoxic group with high serum lactate emphasizes the point that ScvO2 value should be analyzed along with serum lactate levels as complimentary resuscitation endpoints.

A comparison between measured and calculated central venous oxygen saturation in critically ill patients.

BackgroundCentral venous oxygen saturation (ScvO2) is often used to help to guide resuscitation of critically ill patients. The standard gold technique for ScvO2 measurement is the co-oximetry (Co-oximetry_ScvO2), which is usually incorporated in most recent blood gas analyzers. However, in some hospitals, those machines are not available and only calculated ScvO2 (Calc_ScvO2) is provided. Therefore, we aimed to investigate the agreement between Co-oximetry_ScvO2 and Calc_ScvO2 in a general population of critically ill patients and septic shock patients.MethodsA total of 100 patients with a central venous catheter were included in the study. One hundred central venous blood samples were collected and analyzed using the same point-of-care blood gas analyzer, which provides both the calculated and measured ScvO2 values. Bland and Altman plot, intra-class correlation coefficient (ICC), and Cohen’s Kappa coefficient were used to assess the agreement between Co-oximetry_ScvO2 and Calc_ScvO2. Multiple linear regression analysis was performed to investigate the independent explanatory variables of the difference between Co-oximetry_ScvO2 and Calc_ScvO2.ResultsIn all population, Bland and Altman’s analysis showed poor agreement (+4.5 [-7.1, +16.1]%) between the two techniques. The ICC was 0.754 [(95% CI: 0.393–0.880), P< 0.001], and the Cohen’s Kappa coefficient, after categorizing the two variables into two groups using a cutoff value of 70%, was 0.470 (P <0.001). In septic shock patients (49%), Bland and Altman’s analysis also showed poor agreement (+5.6 [–6.7 to 17.8]%). The ICC was 0.720 [95% CI: 0.222–0.881], and the Cohen’s Kappa coefficient was 0.501 (P <0.001). Four independent variables (PcvO2, Co-oximetry_ScvO2, venous pH, and Hb) were found to be associated with the difference between the measured and calculated ScvO2 (adjusted R2 = 0.8, P<0.001), with PcvO2 being the main independent explanatory variable because of its highest absolute standardized coefficient. The area under the receiver operator characteristic curves (AUC) of PcvO2 to predict Co-oximetry_ScvO2 ≥ 70% was 0.911 [95% CI: 0.837–0.959], in all patients, and 0.903 [95% CI: 0.784–0.969], in septic shock patients. The best cutoff value was ≥ 36 mmHg (sensitivity, 88%; specificity, 83%), in all patients, and ≥ 35 mmHg (sensitivity, 94%; specificity, 71%) in septic shock patients.ConclusionsThe discrepancy between the measured and calculated ScvO2 is clinically not acceptable. We do not recommend the use of calculated ScvO2 to guide resuscitation in critically ill patients. In situations where the Co-oximetry technique is not available, relying on PcvO2 to predict the measured ScvO2 value above or below 70% could be an option.

Accuracy and precision of ScvO2 measured with the CeVOX-device: A prospective study in patients with a wide variation of ScvO2-values.

IntroductionCentral-venous oxygen saturation (ScvO2) is a key parameter of hemodynamic monitoring and has been suggested as therapeutic goal for resuscitation. Several devices offer continuous monitoring features. The CeVOX-device (Pulsion Medical Systems) uses a fibre-optic probe inserted through a conventional central-venous catheter (CVC) to obtain continuous ScvO2.ObjectivesSince there is a lack of studies validating the CeVOX, we prospectively analyzed data from 24 patients with CeVOX-monitoring. To increase the yield of lower ScvO2-values, 12 patients were equipped with a femoral CVC.MethodsDuring the 8h study period ScvO2_CeVOX was documented immediately before withdrawal of blood to measure ScvO2 by blood gas analysis (ScvO2_BGA) 6min, 1h, 4h, 5h and 8h after the initial calibration. No further calibrations were performed.ResultsIn patients with jugular CVC (primary endpoint; 60 measurements), bias, lower and upper limits of agreement (LLOA; ULOA) and percentage error (PE) of the estimate of ScvO2 (ScvO2_CeVOX_jug) were acceptable with 0.45%, -13.0%, 13.9% and 16.6%, respectively.As supposed, ScvO2 was lower in the femoral compared to the jugular measurements (69.5±10.7 vs. 79.4±5.8%; p<0.001). While the bias (0.64%) was still acceptable, LLOA (-23.8%), ULOA (25.0%) and PE (34.5%) were substantially higher for femoral assessment of ScvO2 by the CeVOX (ScvO2_CeVOX_fem).Analysis of the entire data-pool with jugular as well as femoral CVCs allowed for a multivariate analysis which demonstrated that the position of the CVC per se was not independently associated with the bias ScvO2_CeVOX—ScvO2_BGA. The amount of the bias |ScvO2_CeVOX–ScvO2_BGA| was independently associated with the amount of the change of ScvO2_CeVOX compared to the initial calibration to ScvO2_BGA_baseline (|ScvO2_CeVOX—ScvO2_BGA_baseline|) as well as with low values of ScvO2_BGA_baseline. Furthermore, increasing time to the initial calibration was associated to the amount of the bias with borderline significance.A statistical model based on |ScvO2_CeVOX—ScvO2_BGA_baseline| and “time to last calibration” derived from an evaluation dataset (80 of 120 datasets, 16 of 24) provided a ROC-AUC of 0.903 to predict an amount of the bias |ScvO2_CeVOX–ScvO2_BGA| ≥5% in an independent validation group (40 datasets of 8 patients).ConclusionThese findings suggest that the CeVOX device is capable to detect stability or instability of ScvO2_BGA. ScvO2_CeVOX accurately estimates ScvO2_BGA in case of stable values. However, intermittent measurement of ScvO2_BGA and re-calibration should be performed in case of substantial changes in ScvO2_CeVOX compared to baseline. Therefore, continuous measurement of ScvO2 with the CeVOX cannot replace ScvO2_BGA in instable patients. On the other hand, CeVOX might be useful for the monitoring of stable patients as a pre-test tool for more differentiated monitoring in case of changes in ScvO2_CeVOX.

The Predictive Ability of PV-ACO2 Gap and PV-ACO2/CA-VO2 Ratio in Shock: A Prospective, Cohort Study.

Compromised tissue oxygenation leads to anaerobiosis, leading to organ failure and death. This study attempts to demonstrate the predictive abilities of the Pv-aCO2 gap and Pv-aCO2/Ca-vO2 ratio in shock patients undergoing resuscitation. In a prospective study, consecutive patients with shock were included. Timed measurements of Pv-aCO2 gap, ScvO2, lactate, and Pv-aCO2/ Ca-vO2 ratio were obtained. The association between the mortality and each variable at all intervals was analyzed. Receiver operating characteristics curves were built. Fifty patients were enrolled. Intensive care unit survivors had a higher Pv-aCO2/ Ca-vO2 ratio at time 0 (0.21, interquartile range [IQR] 0.14 vs. 0.27, IQR 0.38, P = 0.032) and at 3 h (0.27, IQR 0.08 vs. 0.21, IQR 0.12, P = 0.035).Twenty-eight day survival was higher in patients with a low Pv-aCO2 gap at time 0 (7.5, IQR 7 vs. 4.8, IQR 5, P = 0.007).Baseline Pv-aCO2 gap and Pv-aCO2/Ca-vO2 ratio showed good ability to predict 28-day mortality as seen by AUC 0.728 (95% CI 0.578-0.877, P = 0.007) and 0.711 (95% CI 0.563-0.860, P = 0.013). A cut-off point of Pv-aCO2 gap ≥6 mm Hg identified 28-day mortality (75% vs. 45.5%, P = 0.034). The best cutoff values, at baseline, to predict 28-day mortality were 0.25 for the Pv-aCO2/Ca-vO2 ratio (sensitivity 58%, specificity 85%, LR+ 3.86, LR- 0.49) and 6.3 for the Pv-aCO2 gap (sensitivity 58%, specificity 79%, LR+ 2.76, LR- 0.53). This study suggests that Pv-aCO2 gap and Pv-aCO2/Ca-vO2 ratio are discriminating predictors of 28-day mortality and can be used to provide supplementary information during resuscitation in shock.

Prognostic Value of Lactate and Central Venous Oxygen Saturation after Early Resuscitation in Sepsis Patients.

The objective of this study was to evaluate the prognostic value of static and dynamic variables of central venous oxygen saturation (ScvO2) and lactate in patients with severe sepsis or septic shock who underwent early quantitative resuscitation. We also investigated whether ScvO2 measured after initial resuscitation could provide additive prognostic value to that of lactate. We analyzed the sepsis registry for patients presenting to the emergency department and included patients with simultaneous measurements of lactate and ScvO2 at the time of presentation (H0) and 6 hours (H6) after resuscitation. The primary outcome was 28-day mortality and multivariable logistic analysis was used to adjust for confounders. A total of 363 patients were included, and the overall 28-day mortality was 18%. The area under the receiver operator characteristic curve for predicting 28-day mortality was as follows: lactate (H6), 0.81; lactate (H0), 0.73; relative lactate change, 0.67; ScvO2 (H6), 0.65; relative ScvO2 change 0.59; ScvO2 (H0), 0.58. Patients with lactate normalization showed significantly lower 28-day mortality compared to patients without lactate normalization (3% vs. 28%, P<0.01). However, in those who achieved ScvO2 (H6) ≥70%, there was a significant difference in 28-mortality only in patients without lactate normalization (21% vs. 39%, P<0.01) but no difference in those with lactate normalization (4% vs. 3%, P = 0.71). In multivariable analysis, lactate normalization was significantly associated with 28-day mortality (adjusted odds ratio [OR] for 28-day mortality, 0.20; 95% confidence interval [CI], 0.07–0.54; P <0.01), but ScvO2 (H6) ≥70% showed only a marginal association (the adjusted OR for 28-day mortality, 0.51; 95% CI, 0.26–1.01; P = 0.05). ScvO2 (H6) ≥70% was associated with 28-day mortality only in cases without lactate normalization in subgroup analysis (adjusted OR 0.37, 95% CI, 0.18–0.79; P = 0.01). Six-hour lactate was the strongest predictor of 28-day mortality in patients with severe sepsis or septic shock. Six-hour ScvO2 provided additional prognostic value only in cases where lactate values were not normalized after resuscitation.

High central venous saturation after cardiac surgery is associated with increased organ failure and long-term mortality: an observational cross-sectional study

IntroductionCentral venous saturation (ScvO2) monitoring has been suggested to address the issue of adequate cardiocirculatory function in the context of cardiac surgery. The aim of this study was to determine the impact of low (L) (<60%), normal (N) (60%-80%), and high (H) (>80%) ScvO2 measured on intensive care unit (ICU) admission after cardiac surgery.MethodsWe conducted a retrospective, cross-sectional, observational study at three ICUs of a university hospital department for anaesthesiology and intensive care. Electronic patient records of all adults who underwent cardiac surgery between 2006 and 2013 and available admission measurements of ScvO2 were examined. Patients were allocated to one of three groups according to first ScvO2 measurement after ICU admission: group L (<60%), group N (60%-80%), and group H (>80%). Primary end-points were in-hospital and 3-year follow-up survival.ResultsData from 4,447 patients were included in analysis. Low and high initial measurements of ScvO2 were associated with increased in-hospital mortality (L: 5.6%; N: 3.3%; H: 6.8%), 3-year follow-up mortality (L: 21.6%; N: 19.3%; H: 25.8%), incidence of post-operative haemodialysis (L: 11.5%; N: 7.8%; H: 15.3%), and prolonged hospital length of stay (L: 13 days, 9–22; N: 12 days, 9–19; H: 14 days, 9–21). After adjustment for possible confounding variables, an initial ScvO2 above 80% was associated with adjusted hazard ratios of 2.79 (95% confidence interval (CI) 1.565-4.964, P <0.001) for in-hospital survival and 1.31 (95% CI 1.033-1.672, P = 0.026) for 3-year follow-up survival.ConclusionsPatients with high ScvO2 were particularly affected by unfavourable outcomes. Advanced haemodynamic monitoring may help to identify patients with high ScvO2 who developed extraction dysfunction and to establish treatment algorithms to improve patient outcome in these patients.Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-015-0889-6) contains supplementary material, which is available to authorized users.

Prospective evaluation of regional oxygen saturation to estimate central venous saturation in sepsis.

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.

Fluid resuscitation in severe sepsis and septic shock: Shifting goalposts.

Fluid resuscitation in severe sepsis and septic shock: Shifting goalposts.

Venous oxygen saturation.

Early detection and rapid treatment of tissue hypoxia are important goals. Venous oxygen saturation is an indirect index of global oxygen supply-to-demand ratio. Central venous oxygen saturation (ScvO2) measurement has become a surrogate for mixed venous oxygen saturation (SvO2). ScvO2 is measured by a catheter placed in the superior vena cava. After results from a single-center study suggested that maintaining ScvO2 values >70% might improve survival rates in septic patients, international practice guidelines included this target in a bundle strategy to treat early sepsis. However, a recent multicenter study with >1500 patients found that the use of central hemodynamic and ScvO2 monitoring did not improve long-term survival when compared to the clinical assessment of the adequacy of circulation. It seems that if sepsis is recognized early, a rapid initiation of antibiotics and adequate fluid resuscitation are more important than measuring venous oxygen saturation.