Transfusion requirements in obstetric patients with placenta accreta

Providing transfusion support for patients with placenta accreta is a challenging task. There is no consensus on predelivery transfusion planning for these patients and the prevalence of massive transfusion is unknown. With little published experience, it is difficult to predict blood component usage accurately. Therefore, this retrospective study spanning 14 years quantified blood usage and clinical outcome in a group of patients with placenta accreta.

A retrospective medical record review identified 66 patients with placenta accreta who presented for delivery. Data were extracted from the patients' medical records related to patient demographics, pathology diagnosis, blood component usage, operative course, and clinical outcome. Selected variables were analyzed for statistical association with total blood component usage.

The range of blood component usage was 0 to 46 red blood cell (RBC) units, 0 to 48 random-donor platelet unit equivalents, 0 to 64 plasma units, and 0 to 30 cryoprecipitate units. The incidence of transfusion was 95% (mean RBC use, 10 ± 9 units; median, 6.5 units), with 39% of patients requiring 10 or more RBC units and 11% requiring 20 or more RBC units. Blood component use did not differ significantly between the pathology-defined placenta accreta subtypes. Potential clinical laboratory variables that would predict increased blood component use were not identified.

The delivery of patients with placenta accreta is a high-risk procedure that requires multidisciplinary planning and adequate resources to optimize outcome. Transfusion services should have a protocol for managing these cases that addresses preoperative blood component preparation and intraoperative management, should massive hemorrhage occur.