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
Central Venous Oxygen Saturation as a Mortality Marker in Septic Shock: An Observational Study Sundrani Omprakash*, Bhagat Chandrapal, Mishra Aparna and Sahare Kamalkishore Department of Anesthesiology and Critical Care, Pt J.N.M. Medical College & Dr. B.R.A.M. Hospital, India
Abstract Background: Septic shock is a leading cause of morbidity and mortality. Central Venous Oxygen Saturation (ScVO2) is a prognostic marker of patients in septic shock. It is influenced by the oxygen-carrying capacity of blood, organ perfusion and metabolic oxygen consumption. Tissue hypoxia may sometimes occur despite adequate 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 critical care have been studied. It has not been viewed as a mortality marker previously. The present study conducted to explore the association of ScVO2 with 28 days mortality in patients with septic shock, admitted to the Critical Care Unit (CCU) and, to evaluate the usefulness of ScVO2 as a mortality marker. Materials and Methods: A prospective, observational study which was conducted on patients admitted to the CCU with septic shock. 76 patients were enrolled for study based on inclusion and exclusion criteria. Central venous sampling by Central Venous Catheter (CVC) was done for initial ScVO2 value (T0) and was repeated after 6 hours of resuscitation for ScVO2 value (T6) to assess the response to resuscitation. All enrolled patients were observed for a period of 28 days and were divided into 2 groups based on the outcome: Group NS (Non-Survivor group, which included patients who did not survive
*Corresponding author: Omprakash Sundrani, Department of Anesthesiology and Critical Ccare, Pt J.N.M Medical College, Dr. B.R.A.M. Hospital, Raipur, India, Tel: +91 9179893535, E-mail: draparnamishra@gmail.com Citation: Omprakash S, Chandrapal B, Aparna M, Kamalkishore S (2020) Central Venous Oxygen Saturation as a Mortality Marker in Septic Shock: An Observational Study. J Anesth Clin Care 7: 52. Received: April 08, 2020; Accepted: April 27, 2020; Published: May 04, 2020 Copyright: © 2020 Omprakash S, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
at the end of 28 days) and Group S (Survivor group, which included patients who survived at the end of 28 days) and ScVO2 values were compared between the survivor and non-survivor group. Results: In our study, out of 76 patients, 44 patients (57.89%) were non-survivors and 32 patients (42.11%) were survivors. The mean Central Venous Oxygen Saturation (ScVO2) at the time of admission (T0) was 64.00 ± 2.74% among non-survivors and 73.22 ± 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 mortality for value < 70% was 88.64% and specificity was 81.25% (OR = 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 93.75% (OR = 205, 95% CI = 32.23, 1303.97), which reflected that patients with ScVO2 < 70% had a poor prognosis as compared to patients with ScVO2 > 70%. Conclusion: Central Venous Oxygen Saturation (ScVO2) values of less than 70% at the time of admission to CCU (T0) and six hours after the resuscitation (T6) was associated with higher 28 days mortality. From the observations and analysis of our study, it can be concluded that ScVO2 can be used as a predictor of mortality in patients of septic shock. Keywords: Central Venous Oxygen Saturation (ScVO2); Septic shock; Critical Care Unit (CCU)
Introduction Septic shock is a subset of sepsis in which underlying circulatory and cellular/metabolic abnormalities are profound enough to substantially increase mortality and is defined as sepsis along with persistent hypotension requiring vasopressors to maintain MAP ≥ 65mm Hg, and Lactate ≥ 2mmol/L despite adequate fluid resuscitation [1]. Goal-directed therapy helps to predefine resuscitation endpoints to help clinicians at the bedside in the resuscitation of patients in septic shock. Two essential features of early goal-directed therapy are maintenance of Central Venous Pressure (CVP) > 8 mmHg and Central Venous Oxygen Saturation (ScVO2) ≥ 70% [2]. Central Venous Oxygen Saturation (ScVO2) is influenced by the oxygen carrying-capacity of blood, organ perfusion and metabolic oxygen consumption. It reflects the changes in oxygen delivery and consumption ratio. Central venous oxygen saturation (ScVO2) is a prognostic marker of patients in shock which has been underutilized in the critical care setting. Previous studies have used venous oxygen saturation as a therapeutic goal. Tissue hypoxia may sometimes occur despite adequate global oxygen delivery. Unrecognized global tissue hypoxia is associated with an increased risk of mortality and morbidity. Hence accurate detection is of prime importance. Vital signs are not sufficient for accurate and timely detection. In such scenarios, ScVO2 can be useful to predict increased risk of mortality. It can be measured from a blood sample taken from the central venous catheter or pulmonary artery catheter.