External Oblique Intercostal Plane Block for Postoperative Analgesia in Thoracoabdominal Procedures: A Systematic...

The primary objective of this review was to analyze the efficacy of External Oblique Intercostal Plane Block (EOIPB) in reducing the use of opioids in the postoperative period. Time and need for rescue analgesia, postoperative pain scores, and incidence of nausea and vomiting were also evaluated.

The review followed the PRISMA guidelines and was registered on PROSPERO (CRD42024622945). Randomized clinical trials that included adults undergoing thoracoabdominal surgery, comparing EOIPB with general anesthesia, multimodal anesthesia, or other regional blocks, were selected. Search was performed in May 2025 in PubMed, Embase, Scopus, and Cochrane Library databases, with no time or language restrictions. Certainty of the evidence was assessed using the GRADE system.

Fifteen studies involving 899 patients were identified. Results indicated that EOIPB significantly reduced opioid consumption in the first 24 hours postoperatively, compared with standard analgesia (MD: -19.55; 95% CI: -28.50 to -10.60; P <0.0001, I2 =72%) and other regional blocks (MD: -13.15; 95% CI: -24.77 to -1.52; P =0.03, I2 =95%). Heterogeneity was considered moderate to high among studies, related to differences in samples, anesthetic protocols, and assessment methods. Outcomes associated with postoperative pain have a low to very low quality of evidence according to the GRADE method.

The findings support the clinical potential of EOIPB as an effective strategy for postoperative pain control, but without an indication for adoption in clinical practice routine, limited to situations of failure of first-line techniques in analgesia, such as epidural anesthesia.