Shock Index as a Predictor of Postpartum Hemorrhage After Vaginal Delivery: Secondary Analysis of a Multicenter Randomized Controlled Trial

( BJOG. 2024;131:343–352. doi: 10.1111/1471-0528.17634) A reliable predictive indicator of postpartum hemorrhage (PPH) could be a significant medical advance. Shock index (SI) is a measurement dividing heart rate (bpm) by systolic blood pressure (mmHg), with a healthy individual usually between 0.5 and 0.7 and the cutoff, where morbidity and mortality is expected, at 0.9. Elevated SI values have been associated with various cardiovascular conditions including hypovolemia and left heart dysfunction. Previous studies have shown values in the immediate postpartum period to range from 0.5 to 0.9, although these studies excluded women who experienced PPH. Additional research suggests the potential for SI to be used as an early sign of PPH, with a range of 0.9 and 1.0; however, the SI included for each patient was their highest in the postpartum period, which technically means the value is being used as a detection tool rather than a predictor. SI is currently recommended as a tool for PPH management.