Assessing risk factors for peripartum quantified blood loss

Assessing risk factors for peripartum quantified blood loss P ostpartum hemorrhage is increasing worldwide and in the US. 1 Identifying reliable risk factors as well as definitions and measurement tools is essential.In the article "Hemorrhage risk score and peripartum quantified blood loss," Dr. Gutierrez-Disla et al used the Association of Women's Health, Obstetric and Neonatal Nurses (AWOHHN) risk assessment tool to categorize patients as low risk, medium risk, and high risk for postpartum hemorrhage. 2 Specifically, they retrospectively analyzed 1221 patients with term vaginal deliveries at a public New York City hospital to explore the relationship between the AWHONN Hemorrhage Risk Assessment Tool and a categorical value of blood loss of >500 mL (quantitatively measured) since at the time AWOHNN was validated, postpartum hemorrhage for vaginal deliveries was defined as 500 mL.The authors did not specify the resource setting of the city hospital in relation to maternal levels of care; this speaks to the resources at the hospital and the acuity of patients.They also investigated the relationship between the AWHONN Hemorrhage Risk Assessment Tool and the ratio of postdelivery to predelivery hematocrit (hematocrit ratio), using this ratio as a potential estimation of physiologically relevant blood loss.In their results, a high-risk but not medium-risk AWOHNN score was significantly associated with increased quantified blood loss (QBL) as compared to a low-risk AWOHNN score.Body mass index measured as a continuous variable was significantly associated with increased QBL.However, body mass index measured as a categorical variable using the AWOHNN cut-off score of >35 kg/m 2 was not significantly associated with QBL.AWOHNN score was not significantly associated with QBL >500 mL or with the ratio of postdelivery hematocrit with predelivery hematocrit.The authors therefore recommend revising the AWOHNN measure to better reflect medium risk and to consider a different approach for the use of body mass index as part of the AWOHNN risk score.In this article, it is notable that only vaginal deliveries were evaluated, knowing that deliveries by cesarean will have higher QBL.