The Validation of a New Method to Assess Estimated Blood Loss in the Obstetric Population Undergoing Cesarean Delivery

Abstract Background Postpartum hemorrhage is the leading cause of maternal mortality in developing countries and the primary cause of one-quarter of all maternal deaths globally. Inaccuracy in estimating blood loss obscures the diagnosis of postpartum hemorrhage and its management. Objective Our objective was to compare assessment of blood loss using the quantitative Triton TM system (Gauss Surgical, Inc., Los Altos, CA) with other measures of blood loss in women undergoing cesarean delivery. Study Design Women scheduled for cesarean deliveries at our facility were included. Intraoperative blood loss was measured using the Triton TM , which was masked to the clinical team, as well as estimated by the surgeon (EBL). The relation between the 2 methods (Triton TM and EBL) and postoperative Hgb as well as ΔHgb (postoperative minus preoperative Hgb) was determined using the Spearman correlation. Triton TM measurement and EBL were compared between women with ΔHgb in the upper quartile (cases) vs. all other quartiles (control). Prediction of ΔHgb in the upper quartile was also evaluated for each method, and the area under the ROC curves (AUCs) was compared. Results The trial enrolled 242 patients. The mean blood loss estimated by the Triton TM device was significantly lower than that estimated by clinical judgment (415.3 ± 260.6 vs. 799.6 ± 215.6 mL, P TM estimate correlated best with ΔHgb. Seventy patients had ΔHgb in the upper quartile (ΔHgb ≥ 2). There was a significant difference in the Triton TM blood loss measurement between cases and controls but no difference with EBL. Triton TM , but not EBL, was predictive of ΔHgb ≥ 2 g/dL (Triton TM : AUC = 0.66, 95% CI [0.58, 0.74]; P P  = .45). Conclusion The Triton TM system provides a better estimate of blood loss than the visual estimate. Clinical trials to evaluate its benefit are warranted.