Aortic balloon occlusion in distal zone 3 reduces blood loss from obstetric hemorrhage in placenta accreta spectrum

Peripartum hemorrhage is a significant cause of maternal death. We developed a standardized, multidisciplinary cesarean hysterectomy protocol for placenta accreta spectrum (PAS) using prophylactic resuscitative endovascular balloon occlusion of the aorta (REBOA). We initially placed the balloon in proximal zone 3, below the renal arteries. An internal review revealed more bleeding than expected, and we subsequently changed our protocol to occlude the origin of the inferior mesenteric artery (distal zone 3), to decrease blood flow through collateral circulation. We hypothesized that distal zone 3 occlusion would reduce blood loss and transfusion volume and may permit a longer duration of occlusion compared with proximal zone 3 occlusion without increasing ischemic complications. METHODS: We conducted a single-center retrospective cohort study of patients with suspected PAS who underwent REBOA-assisted cesarean hysterectomy from December 2018 to March 2022. Medical records of all patients with PAS were reviewed. Data were extracted from hospital admission through 3 months postpartum. RESULTS: Forty-four patients met the inclusion criteria. Nine never had the balloon inflated. Eighteen patients had placement in proximal zone 3, whereas twenty-six patients had placement in distal zone 3. Background and clinical characteristics were similar in both groups. Placental pathology was obtained in every case. After adjusting for relevant risk factors, multivariate analysis revealed that distal occlusion was associated with a 45.9% (95% confidence interval, 23.8–61.6%) decrease in estimated blood loss, 41.5% (13.7–60.4%) decrease in red blood cell transfusion volume, and 44.9% (13.5–64.9%) reduction in total transfusion volume. There were no vascular access or resuscitative endovascular balloon occlusion of the aorta–related complications in either group. CONCLUSION: This study highlights the safety of prophylactic REBOA in planned cesarean hysterectomy for PAS and provides a rationale for distal zone 3 positioning to reduce blood loss. Resuscitative endovascular balloon occlusion of the aorta should be considered at other institutions with placenta accreta programs, especially in patients with extensive collateral flow. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.