A systematic review and meta-analysis of randomized controlled trials on the effects of internal iliac artery balloon occlusion in placenta previa and placenta accreta spectrum in reducing perioperative bleeding

Background: Preoperative prophylactic balloon occlusion (PPBO) of internal iliac arteries (IIAs) in placenta previa and placenta accreta spectrum (PAS) has been widely used as a preventive adjuvant technique to reduce blood loss and to preserve fertility. Nevertheless, the efficacy of PPBO is based primarily on retrospective studies. Objective: To examine the effectiveness of PPBO of the IIAs in placenta previa and PAS in reducing perioperative bleeding. Search strategy: MEDLINE, EMBASE, Web-of-Science, Scopus, the Cochrane Library, and ClinicalTrials.gov were searched from their inception to July 2023. Selection criteria: Randomized controlled trial (RCT) in which the use of PPBO on the IIAs was compared to non-use. Data collection and analysis: The primary outcome was number of packed red blood cell (RBC) units transfused. We executed meta-analysis using a random-effects model. Quality of the studies was assessed using the Cochrane Risk-of-Bias tool. The GRADE criteria were used to assess evidence certainty. Main results: Of 164 reports identified, three RCTs representing 167 women (83 and 84 in the intervention and control groups, respectively) were eligible. Mean number of RBC units transfused was 4.52 ± 1.70 and 3.70 ± 1.88 in the intervention and control groups, respectively (weighted mean difference, 1.04; 95% CI: 0.52–1.55; P = 0.001; I², 0%; low certainty evidence). Transfusion of other blood products was comparable. Incidence of postoperative fever was higher (P = 0.024) and hospitalization duration was longer (P = 0.001) in the intervention group compared to the control group. Conclusions: Use of PPBO of the IIAs in placenta previa and PAS was associated with increase in number of RBC units transfused.