The golden hour for postpartum hemorrhage: Results from a prospective cohort study

Abstract

Postpartum hemorrhage (PPH) has been a leading cause of global maternal mortality over the last 25 years. 1,2 It affects mainly young women in low-and middle-income countries and its impact on maternal mortality has increased from 68% in 1990 to more than 80% in 2015. [1][2][3] PPH has also increased in high-income countries where there is a higher rate of medicalization contributing to the condition. [4][5][6] PPH is also associated with maternal near-miss cases, Intensive care unit (ICU) admission, and massive blood transfusion. 7,8 Given the low ability to predict PPH according to prelabor characteristics, early recognition and treatment of PPH are essential. 9,10 The World Health Organization (WHO) defines PPH as blood loss >500 ml within 24 h after childbirth and severe PPH as blood loss >1000 ml. 11 Although these thresholds may not necessarily imply severe maternal morbidity or serious hazard to women, they are

Shock index as a predictor of postpartum haemorrhage after vaginal delivery: Secondary analysis of a multicentre randomised controlled trial

“…[18][19][20][21][22] Only a few studies have investigated the predictive performance of SI as an early predictor of PPH in a general population of women vaginal delivery including non-PPH women. 16,27,39 Most of these studies reported AUROC values for postpartum SI to discriminate blood loss ≥1000 ml higher than our findings, 16,27 with AUROC values of 0.70 or higher, a range considered acceptable by most authors. 29 These studies present methodological limitations by considering the highest SI value during the postpartum period 16,27 and failing to exclude women who had already met the outcome criteria when SI was measured.…”

“…A prospective cohort of 270 unselected women after vaginal delivery conducted in Brazil in 2015 found an AUROC, sensitivity and specificity of SI for discriminating QBL ≥1000 ml similar to ours. 39 Those authors considered the mean value of SI between 21-40 and 41-60 minutes after delivery, an approach to the SI measurement timing consistent with ours, without the methodological limitation associated with using the highest SI value. 39 SI measured shortly after delivery is a poor predictor of PPH (QBL ≥1000 ml or cPPH).…”

“…39 Those authors considered the mean value of SI between 21-40 and 41-60 minutes after delivery, an approach to the SI measurement timing consistent with ours, without the methodological limitation associated with using the highest SI value. 39 SI measured shortly after delivery is a poor predictor of PPH (QBL ≥1000 ml or cPPH). These results suggest that SI at or after 15 minutes after delivery is unlikely to be a promising tool to predict PPH in an unselected population of women after vaginal delivery.…”

“…The predictive performance values of three prespecified SI cut-off values -0.7, 0.9 and 1.1 -were analysed and the corresponding sensitivity, specificity, and positive and negative predictive values calculated in each relevant study population. These cut-offs were chosen based on the previous literature and corresponded to the upper bound in healthy young adults (0.7 value), 5,6 to the classical threshold described as the best predictor of PPH (0.9 value), 16,20,21,27,39 and to the 97th percentile of the SI distribution at 15 and 30 minutes in our source population (1.1 value). We also estimated the association between each SI cut-off and each outcome (QBL ≥1000 ml and cPPH) by calculating their odds ratios with univariate logistic regression.…”

“…29 These studies present methodological limitations by considering the highest SI value during the postpartum period 16,27 and failing to exclude women who had already met the outcome criteria when SI was measured. 16,27,39 In their multicentre retrospective study, Ushida et al 16 evaluated the usefulness of the highest level of SI measured in postpartum 'as an early sign of hypovolemia' in vaginal deliveries among 30 820 women in Japan with a AUROC value of 0.70 (LCI 0.68). The sensitivity values of SI for discriminating blood loss ≥1000 ml were respectively 84.2% (95% CI 82.0-86.3), 45.6% (95% CI 42.6-48.5) and 19.2% (95% CI 16.9-21.5) for SI ≥0.7, 0.9 and 1.1, respectively.…”