Transfusion Medicine in a Multidisciplinary Approach to Morbidly Adherent Placenta: Preparing for and Preventing the Worst

The increasing incidence of placenta accreta has paralleled the rise in its greatest risk factor: cesarean delivery. In placenta accreta, the abnormal invasion of the chorionic villi into the myometrium prevents separation of the placenta at delivery, and the myometrium is unable to contract to prevent hemorrhage. Spontaneous uterine rupture and hemoperitoneum may also occur in the setting of placenta percreta. The average blood loss during a delivery complicated by placenta accreta is 2 to 5 L, compared to less than 0.5 L for a normal spontaneous vaginal delivery and less than 1 L for a cesarean delivery. Transfusion support for these patients, including preoperative blood component planning, is challenging for the transfusion service, and there is no consensus on how transfusion services should prepare for such cases. Herein, we review the value of a multidisciplinary approach in minimizing and supporting maternal hemorrhage in placenta accreta, predictors of hemorrhage, blood product preparation, potential strategies to limit blood loss, and intraoperative management considerations. We also highlight future opportunities and challenges in this unique group of patients.