Omprakash S, et al., J Anesth Clin Care 2020, 7: 052 DOI: 10.24966/ACC-8879/100052 HSOA Journal of Anesthesia and Clinical Care Research Article at the end of 28 days) and Group S (Survivor group, which included Central Venous Oxygen Satu- patients who survived at the end of 28 days) and ScVO values 2 were compared between the survivor and non-survivor group. ration as a Mortality Marker in Results: In our study, out of 76 patients, 44 patients (57.89%) were non-survivors and 32 patients (42.11%) were survivors. The mean Septic Shock: An Observational Central Venous Oxygen Saturation (ScVO ) at the time of admis- 2 sion (T0) was 64.00 ± 2.74% among non-survivors and 73.22 ± Study 2.62% among survivors, and after six hours of resuscitation (T6) it was 63.30 ± 2.91% among non-survivors and 73.97 ± 2.31% among survivors. The sensitivity of ScVO2 at T0 in terms of mor- Sundrani Omprakash*, Bhagat Chandrapal, Mishra Aparna and tality for value < 70% was 88.64% and specificity was 81.25% (OR Sahare Kamalkishore = 33.8, 95% CI = 9.34, 122.35) and sensitivity of ScVO2 at T6 in terms of mortality for value < 70% was 93.18% and specificity was Department of Anesthesiology and Critical Care, Pt J.N.M. Medical College & 93.75% (OR = 205, 95% CI = 32.23, 1303.97), which reflected that Dr. B.R.A.M. Hospital, India patients with ScVO2 < 70% had a poor prognosis as compared to patients with ScVO2 > 70%. Conclusion: Central Venous Oxygen Saturation (ScVO2) values of Abstract less than 70% at the time of admission to CCU (T0) and six hours after the resuscitation (T6) was associated with higher 28 days Background: Septic shock is a leading cause of morbidity and mor- mortality. From the observations and analysis of our study, it can tality. Central Venous Oxygen Saturation (ScVO ) is a prognostic 2 be concluded that ScVO2 can be used as a predictor of mortality in marker of patients in septic shock. It is influenced by the oxygen-car- patients of septic shock. rying capacity of blood, organ perfusion and metabolic oxygen con- Keywords: Central Venous Oxygen Saturation (ScVO ); Septic sumption. Tissue hypoxia may sometimes occur despite adequate 2 shock; Critical Care Unit (CCU) global oxygen delivery. In such scenarios, ScVO2 can be useful to predict increased risk of mortality. In the previous studies on ScVO2, its importance as a tissue oxygen marker and its importance in crit- Introduction ical care have been studied. It has not been viewed as a mortali- ty marker previously. The present study conducted to explore the Septic shock is a subset of sepsis in which underlying circulato- association of ScVO with 28 days mortality in patients with septic 2 ry and cellular/metabolic abnormalities are profound enough to sub- shock, admitted to the Critical Care Unit (CCU) and, to evaluate the stantially increase mortality and is defined as sepsis along with per- usefulness of ScVO as a mortality marker. 2 sistent hypotension requiring vasopressors to maintain MAP ≥ 65mm Materials and Methods: A prospective, observational study which Hg, and Lactate ≥ 2mmol/L despite adequate fluid resuscitation [1]. was conducted on patients admitted to the CCU with septic shock. Goal-directed therapy helps to predefine resuscitation endpoints to 76 patients were enrolled for study based on inclusion and exclusion help clinicians at the bedside in the resuscitation of patients in septic criteria. Central venous sampling by Central Venous Catheter (CVC) shock. Two essential features of early goal-directed therapy are main- was done for initial ScVO2 value (T0) and was repeated after 6 hours tenance of Central Venous Pressure (CVP) > 8 mmHg and Central of resuscitation for ScVO value (T6) to assess the response to re- 2 Venous Oxygen Saturation (ScVO2) ≥ 70% [2]. suscitation. All enrolled patients were observed for a period of 28 days and were divided into 2 groups based on the outcome: Group Central Venous Oxygen Saturation (ScVO2) is influenced by the NS (Non-Survivor group, which included patients who did not survive oxygen carrying-capacity of blood, organ perfusion and metabolic oxygen consumption. It reflects the changes in oxygen delivery and *Corresponding author: Omprakash Sundrani, Department of Anesthesiology consumption ratio. Central venous oxygen saturation (ScVO2) is a and Critical Ccare, Pt J.N.M Medical College, Dr. B.R.A.M. Hospital, Raipur, In- prognostic marker of patients in shock which has been underutilized dia, Tel: +91 9179893535, E-mail: [email protected] in the critical care setting. Previous studies have used venous oxygen Citation: Omprakash S, Chandrapal B, Aparna M, Kamalkishore S (2020) saturation as a therapeutic goal. Tissue hypoxia may sometimes occur Central Venous Oxygen Saturation as a Mortality Marker in Septic Shock: An despite adequate global oxygen delivery. Unrecognized global tissue Observational Study. J Anesth Clin Care 7: 52. hypoxia is associated with an increased risk of mortality and mor- Received: April 08, 2020; Accepted: April 27, 2020; Published: May 04, 2020 bidity. Hence accurate detection is of prime importance. Vital signs Copyright: © 2020 Omprakash S, et al. This is an open-access article distribut- are not sufficient for accurate and timely detection. In such scenarios, ed under the terms of the Creative Commons Attribution License, which permits ScVO2 can be useful to predict increased risk of mortality. It can be unrestricted use, distribution, and reproduction in any medium, provided the orig- measured from a blood sample taken from the central venous catheter inal author and source are credited. or pulmonary artery catheter. Citation: Omprakash S, Chandrapal B, Aparna M, Kamalkishore S (2020) Central Venous Oxygen Saturation as a Mortality Marker in Septic Shock: An Observa- tional Study. J Anesth Clin Care 7: 52. • Page 2 of 6 • In the previous studies on ScVO2, its importance as a tissue ox- Statistical analysis ygen marker and its importance in critical care have been studied. It has not been viewed as a mortality marker previously. In the present Univariate analyses were used to evaluate the correlations be- study, the association of central venous oxygen saturation with 28 tween all the variables. Multivariate logistic regression analysis using days mortality in patients with septic shock admitted to the Critical the mortality risk factors determined by univariate analysis was used Care Unit (CCU) has been explored, to evaluate the usefulness of to find the independent predictor of mortality. A Receiver Operating Characteristic (ROC) curve was plotted to determine the most appro- ScVO2 as a mortality marker. priate cut off value of central venous oxygen saturation (ScVO2) at T0 Materials and Methods and T6 used independently to predict the mortality. Categorical data are expressed as percent, and continuous vari- An observational, prospective study conducted in the Department ables are expressed as mean ± SD. Continuous variables were com- of Anesthesiology and Critical care at Pt. J.N.M. Medical College & pared by using independent Student’s t-test. Odds Ratios (OR) is Dr. B.R.A.M. Hospital, Raipur (C.G) from April 2018 to July 2019 to given with the 95% CI. A two-tailed P-value < 0.05 was considered predict mortality in patients admitted to the Critical Care Unit (CCU) statistically significant. using ScVO2% at T0 and T6. After applying inclusion and exclusion criteria, a total of 76 patients were selected for study and all of them Results were followed over a period of 28 days. Among 76 patients enrolled in the study 72.37% (n = 55) were Study Design: Prospective, Observational study male and 27.63% (n = 21) were female. Male: Female distribution in Study location: Pt. J.N.M. Medical College and Dr. B.R.A.M. Hos- NS and S group was 37:7 and 18:14 respectively. The total number pital, Raipur (C.G.) of patients who died in the follow-up duration of 28 days was 44 (57.89%) and was grouped as non-survivors whereas the remaining Study Duration: April 2018 to July 2019 32 (42.11%) patients who survived were grouped under the survivor Sample size: 76 group. The difference in gender distribution between group NS and group S was found to be statistically significant (p-value = 0.01), with Sample size calculation: Using epitool by one-tailed test, taking con- odds of non-survival was found more for male gender (OR = 0.24, fidence of 95%. 95% CI = 0.08, 0.71). (Table 1), (Figures 1-3). Study population: Patients admitted to the Critical Care Unit (CCU) of Dr. B.R.A.M. Hospital. Variable Groups based on Outcome (mortality at day 28) Group NS Group S Total Inclusion Criteria: Septic shock patients of either sex aged ≥ 18 Gender years of age. n=44 (57.89%) n=32 (42.11%) N=76 (100%) Male 37 (67.27%) 18 (32.73%) 55 (100%) Exclusion Criteria Female 07 (33.33) 14 (66.67%) 21 (100%) 1. Patients with contraindication to central venous catheterization. H/O Chronic Disease 2. Age < 18 years. Present 32 (64%) 18 (36%) 50 (100)% Absent 12 (46.15%) 14 (53.85%) 26 (100)% 3. Patients with systolic dysfunction. Ventilator Use 44 (57.89%) 32 (42.11%) 76 (100%) 4. Patients revived by Cardio-Pulmonary Resuscitation (CPR). Vasopressors Use 44 (57.89%) 32 (42.11%) 76 (100%) 5. Patients with imminent death. ScVO2% < 70% at T0 to 3 (33.33%) 6 (66.67%) 9 (100%) ScVO2% ≥ 70% at T6 Methodology Table 1: Demographic, clinical characteristics, treatment and outcome of As the patient got shifted to the CCU, the patient’s medical re- enrolled 76 patients. cords were reviewed; demographic data, clinical data, vital signs, diagnosis and associated co-morbidities were recorded.