550 Autotransfusion of vaginally shed blood during obstetric hemorrhage: a matched cohort atudy

Abstract

Cell salvage and autotransfusion (AT) has gained acceptance as an effective tool for management of hemorrhage during cesarean delivery. However, most obstetric hemorrhage (OBH) occurs following vaginal delivery. Given concern for contamination of vaginally shed blood, AT for management of OBH following vaginal delivery has not been as widely adopted. We aimed to determine the efficacy and safety of AT for vaginal deliveries complicated by OBH. This is a single center retrospective matched cohort study of vaginal deliveries complicated by OBH from 2014-2020. Patients that received AT for OBH following vaginal delivery were each matched to 4 controls that delivered vaginally with an EBL within 200 mL. Our cohort was limited to EBL below 2400 mL, because cell salvage was consistently utilized above this threshold. The primary outcome was allogeneic transfusion of packed red blood cells (RBCs). Unadjusted analyses were performed using Fisher’s exact test and Student’s paired t test. Adjusted analyses were performed using multivariable logistic and linear regression. During the study period, 36 AT patients were matched to 144 unexposed controls. AT patients were more likely to be a patient of MFM, identify as Non-Hispanic Black, have preeclampsia, and use tobacco. There was no significant difference in transfusion of packed RBCs when AT cases were compared to controls (OR 1.2; 95% CI 0.6-2.7, p=0.5, AT referent). No AT patients were transfused ≥ 4 units of packed RBCs compared to 3.3% of controls (n=6; p=0.601). Notably, AT patients had a less drastic decline in hemoglobin compared to controls across all values of EBL (p=0.003; Figure 1). There were no detectable differences in venous thromboembolism events or rates of individual or composite infectious, pulmonary or renal complications (Table 1). Our data suggest that cell salvage and autotransfusion of vaginally shed blood is a safe and effective tool for management of obstetric hemorrhage following vaginal delivery.View Large Image Figure ViewerDownload Hi-res image Download (PPT)