Blood Loss Measurement Technique That Predicts Decrease in Hemoglobin After Cesarean Delivery [17F

Abstract

INTRODUCTION: To identify the blood loss technique that best predicts a decrease in hemoglobin (Hgb) >3 g/dL 24 hours after cesarean delivery (CD). METHODS: This was an IRB approved, retrospective review of women with singleton pregnancies who underwent cesarean delivery at >=34 weeks' gestation between July 1, 2017 and June 30, 2018. Women had blood loss measured by visually estimation (EBL), gravimetric estimation (QBL), Gauss Surgical's Triton (TBL) and a 24-hour postoperative complete blood count. The primary outcome was the optimal threshold for decrease in Hgb >3 g/dL by the area under the receiver-operating characteristic (ROC) curve (AUC) using blood loss estimation technique. RESULTS: Of the 446 women meeting inclusion criteria, 65 (15%) had a decrease in Hgb >3 g/dL. Women who had a decrease in Hgb >3 g/dL compared to women without a decreased in Hgb >3 g/dL were more likely to have increased gestational age, postoperative tachycardia (heart rate >100 beats per minute) at 12 and 24 hours post CD, postpartum hemorrhage by QBL and TBL and require blood product transfusion, (all P<0.05). None of the blood loss measurement techniques had a high AUC for predicting women with decrease in Hgb >3 g/dL (EBL 0.64 [95% CI 0.56-0.71], QBL 0.67 [95% CI 0.60-0.74] and TBL 0.70 [95% CI 0.63-0.77], P=0.13. All techniques had low sensitivity and high specificity for women with PPH and decrease in Hgb >3 g/dL. CONCLUSION: Blood loss at time of cesarean, measured by EBL, QBL or TBL, is a poor predictor for a decrease in Hgb by >3 g/dL.