///2019 Abstract Details
2019 Abstract Details2019-07-13T07:45:15-05:00

Introduction of a Novel System for Quantitating Blood Loss After Vaginal Delivery: A Retrospective Before-After Study

Abstract Number: F3H-511
Abstract Type: Original Research

Mario I Lumbreras-Marquez MBBS1 ; Sharon C Reale MD2; Daniela A Carusi MD MS3; Julian N Robinson MD4; Kara G Fields MS5; Michaela K Farber MD MS6


Postpartum hemorrhage (PPH) is the most common preventable cause of maternal mortality, and mechanisms to enhance quantitation are warranted (1). Both volumetric and gravimetric blood loss (BL) measurements are superior to visual estimation of blood loss (EBL), but a combination of these quantitative methods has not been evaluated. Here we compare PPH detection by EBL to a novel device for quantitation of BL (QBL) that combines both volumetric and gravimetric measurements.


After IRB approval, patients who had a vaginal delivery between October 1, 2017 and April 30, 2018 were identified. A QBL device was implemented on January 1, 2018. PPH and related outcomes were compared before (EBL) and after (QBL) device implementation. The primary outcome was incidence of PPH (BL > 500mL). Secondary outcomes were BL > 1000mL, mean BL, transfusion requirement, 2o uterotonic or vasopressor use, surgical procedures, and a composite outcome of interventions related to PPH. Post-hoc secondary outcomes assessed in the subgroup who had both pre- and post-delivery hematocrits (Hct) were nadir Hct, the incidence of postpartum Hct reduction > 10%, and the difference between EBL or QBL and calculated blood loss (CBL). Besides immediate post-delivery BL, all outcome comparisons were adjusted for potential confounders via inclusion of propensity score quintiles as covariates in multivariable regression models.


PPH (BL > 500 mL) was detected in 26.5% (QBL) vs. 11.0% (EBL) of patients (aOR 2.94 (95% CI: 2.24, 3.87; p < 0.001)). BL > 1000 mL was identified in 6.7% vs. 2.0% of patients, respectively (aOR 3.28 (1.92, 5.78; p < 0.001)). There was no difference in other secondary outcomes. Median BL was 307 vs. 300 mL in QBL vs. EBL groups, with more even distribution by QBL (Figure). In the subgroup, mean difference between delivery BL and CBL was smaller in the QBL (mean ± SD: -301 ± 568 mL) vs. EBL group (-664 ± 631 mL; adjusted difference in means (95% CI): 353 mL (209, 497); p < 0.001).


In this before-after study, use of comprehensive QBL increased PPH detection after vaginal delivery compared to EBL, but did not yield any difference in PPH-related interventions or outcomes. Closer proximity of QBL to CBL compared to EBL vs. CBL suggests accuracy of the QBL device. Further studies on the utility of QBL in different clinical settings are warranted.


1.Main EK. Obstet Gynecol. 2015;126(1):155-162.

SOAP 2019