Change in Shock Index as a Predictor of Transfusion Requirement [07M

Abstract

INTRODUCTION: Early identification of PPH is difficult. Shock index (SI) (SI=HR/SBP) of (>0.9) has demonstrated good prediction of PPH, and identify identification of patients requiring massive transfusion. Our objective is to determine if there is a change in SI on admission to postpartum or at time of transfusion after which there is an increased transfusion requirement or morbidity. METHODS: IRB approved, retrospective cohort of patients who received blood transfusion at a University based hospital, 2017-2018. SI calculated; at time of admission, after delivery, and prior to transfusion. Patients with invasive carcinoma, with fetus of non-viable gestational age, and incomplete charts were excluded. Spearman correlate coefficient, univariable logistic regression, and ROC analyses were performed. RESULTS: 160 patients; 117/160 (73%) delivered by cesarean, 37/160 (23%) vaginally, and 6/160 (4%) operative vaginal delivery. Mean admission hemoglobin was 10.8 (± 1.5). Median EBL was 1320 mL (250-6000 mL). 77/160 (48%) of patients received 2 units of PRBC, 26/160 (17%) received 3 units of PRBC, 24/160 (15%) received 4 units of PRBC and 33/160 (20%) received ≥5 units of PRBC. Change in SI from admission to postpartum had a correlation coefficient of 0.022 and a P value of .78. Change in SI from admission to pre-transfusion had a correlation coefficient of 0.128 and a P value of .11. CONCLUSION: Changes in SI from admission to immediately postpartum or pre-transfusion do not show any correlation or predictive value for increasing morbidity, or transfusion requirements. This demonstrates change in SI is a poor predictor of morbidity and transfusion requirements.