Introduction
Postpartum hemorrhage is the leading cause of pregnancy-related death in the USA.1 Placenta accreta and its more severe variants occur in 1 of every 272 pregnancies2 and are a major cause of massive peripartum hemorrhage, accounting for 46% of cesarean hysterectomies (CHyst) performed.3 Placenta accreta spectrum (PAS) disorder is further subclassified into placenta accreta, increta, and percreta, based on the extent of myometrial and extrauterine pelvic invasion. With PAS, the absence of the decidua basalis layer inhibits the typical separation of the placental unit from the uterus, after delivery of the fetus. This, in turn, leads to significant maternal morbidity, including increased blood loss, hemorrhage, and need for blood transfusions. Placenta accreta cases involve abnormal attachment of the placental villi into but limited to the myometrial layer, with placenta increta cases exhibiting deep myometrial invasion. Placenta percreta cases exhibit placental villi penetrating through the myometrium to the serosa of the uterus and beyond (figure 1).
Prior studies have demonstrated that in patients undergoing CHyst due to PAS disorder, 90% required blood transfusion, with over 40% requiring massive blood transfusion. Massive transfusion was defined as more than 10 units packed red blood cells (PRBCs) administered intraoperatively, as per Wright et al.4–6 Different methods, including aortic occlusive balloon use and clamping, have been used in an attempt to decrease blood loss.7–9 Resuscitative endovascular balloon occlusion of the aorta (REBOA) is one such mechanism for achieving temporary aortic occlusion. REBOA was originally used in the military, with now improved technology and expanded use in the civilian trauma population.10 11 The ER-REBOA Catheter was approved by the Food and Drug Administration in 2015 for temporary occlusion of large vessels in patients requiring emergency control of hemorrhage as an alternative to open aortic occlusion.12 13 This minimally invasive procedure involves placement of an endovascular balloon through a French femoral arterial line into the abdominal aorta, offering an alternative to abdominal aortic clamping. Temporary occlusion of the abdominal aorta is achieved, allowing for proximal vascular control while still providing cardiac and cerebral perfusion. Furthermore, for the purposes of pelvic bleeding control, the balloon can be positioned in the distal portion of aortic zone 3, ideally between the aortic bifurcation and the inferior mesenteric artery14 15 (figure 2).
The use of REBOA has expanded from trauma to emergency surgery with non-traumatic intra-abdominal hemorrhage.16 17 More recently, there has been an interest in the use of the REBOA procedure for obstetrical patients, given the risk of significant hemorrhage with complicated deliveries, namely CHyst deliveries. Given the novelty of this procedure in the obstetrical population, there is limited literature regarding the use of this modality with CHyst performed for PAS disorders, especially in the US population. The use of REBOA in patients with PAS disorder is mainly limited to case series and systematic reviews of the available literature. The reported data combine both prophylactic and emergent placements of REBOA, with reported studies conducted outside the USA.18–21
Ordoñez et al21 reported on the experience at a Colombian level I trauma center which prophylactically used REBOA in 12 women undergoing an elective cesarean section for morbid placentation with a median estimated blood loss (EBL) of 1500 mL. The authors found the use of REBOA decreased intraoperative blood loss and the number of PRBCs transfused, without REBOA-associated complications. Manzano-Nunez and colleagues20 performed a systematic review of the use of REBOA in morbidly adherent placental cases and found REBOA decreased the amount of blood loss with a low complication rate. The use of aortic occlusive procedures, however, has raised concern due to the associated complications of pseudoaneurysm and distal embolic events with the potential for limb ischemia requiring additional interventions.12 A recent study by Whittington et al22 appears to be first in describing a US series with the use of REBOA both prophylactically and emergently in a population of patients with PAS disorder. There were no vascular complications in the study patients who underwent REBOA placement in a prophylactic setting, with three of four surviving emergent placement patients experiencing vascular complications.
The available literature has established that the use of REBOA is feasible during CHyst and is associated with decreased blood loss. In the current investigation, we studied several relatively unexplored concepts pertaining to prophylactic REBOA utilization in a population of patients with PAS disorder. We measured whether decrease in PRBC transfusion requirements is preserved when REBOA is placed in distal aortic zone 3; we assessed the feasibility of avoiding fluoroscopy use for REBOA placement confirmation in distal zone 3 with utilization of manual palpation instead. We also examined differences in postoperative length of stay (LOS), onset of postoperative ileus, and admission to surgical intensive care unit (SICU) between REBOA and non-REBOA groups, all points yet to be defined in the literature.