Ultrasound-guided transversus abdominis plane block is an effective opioid-sparing alternative to epidural anesthesia in open abdominal aortic aneurysm repair

Abstract

ObjectiveThis study evaluated the effectiveness of ultrasound-guided transversus abdominis plane (TAP) blocks compared with epidural (EPI) and general anesthesia (GA) in managing postoperative pain following open abdominal aortic aneurysm (AAA) repair. MethodsA retrospective review was conducted on 61 elective open AAA repairs performed between January 2016 and December 2021. Patients were categorized into three groups: GA, GA plus EPI, and GA plus TAP block. The primary outcome measured was opioid requirements, reported as morphine milligram equivalents (MME) at 48, 72, and 120 hours postoperatively. The additional opioid requirements between 48 and 72 hours (ΔMME₁) and between 72 and 120 hours (ΔMME₂) were also evaluated. Secondary outcomes included vasopressor requirements, extubation in the operating room, and length of stay in the intensive care unit and hospital. ResultsThe mean MMEs at 48, 72, and 120 hours were statistically significant across all groups. The mean MME at 48 hours was 51.1 ± 71.9 in the TAP group compared with 140.5 ± 121.7 in the GA group. Pairwise comparisons showed a significant difference between the GA and TAP groups at 48 hours (P = .002), whereas the difference between EPI and TAP at 48 hours was not significant (P = .098). Additional opioid requirements between 48 and 72 hours after surgery (ΔMME₁) showed a significant difference between EPI and TAP (P = .045). All groups had significantly different MMEs at 72 hours, with no significant differences observed at 120 hours. Secondary outcomes were not significantly different across the groups. ConclusionsTAP blocks provide effective postoperative pain control with decreased opioid requirements similar to EPI anesthesia during the first 48 hours postoperatively. This factor makes TAP blocks a viable alternative to EPI anesthesia in open AAA repairs. Further multicenter studies are recommended to validate these findings.