Shock index as a predictor of maternal outcome in postpartum hemorrhage

Abstract

Background: Postpartum hemorrhage (PPH) is one of the leading causes of maternal mortality. Shock index (SI) is a hemodynamic parameter for the early identification of hypovolemic shock. This study was conducted to establish the thresholds of SI for predicting the adverse outcomes in PPH and to compare the predictive value of SI with heart rate (HR) and mean arterial pressure (MAP) at the first hour of hemorrhage. Materials and Methods: This prospective cohort study was conducted at the Department of Obstetrics and Gynecology in a tertiary care hospital at India. The study population consisted of 100 patients who were randomly selected and delivered after 28 weeks with visual blood loss greater than 500 mL in normal vaginal delivery and greater than 1000 mL during lower segment cesarean section (LSCS). HR, MAP, and SI were noted at the first hour of hemorrhage. Area under the receiver operator curve (AUROC) for SI, MAP, and HR for predicting the adverse outcomes such as need for blood transfusion (≥4 blood products), need for intensive care unit (ICU) admission, and need for operative interventions was established and compared. The Threshold value of SI predictive for the above outcomes was established. Results: SI greater than 1 was associated with the need for operative intervention, SI greater than 1.3 was associated with ICU admission, massive blood transfusion, and increased morbidity, and SI greater than 1.6 was associated with mortality. AUROC of SI [95% confidence interval (CI)] was highest when compared with MAP and HR for almost all outcomes. Conclusion: Shock index is a simple, noninvasive, and sensitive tool that can be used in PPH triage.