Effects of Transverse Abdominis Plane (TAP) Block on the MACBAR of Sevoflurane in Gynecologic Patients with Laparoscopic Pneumoperitoneal Stimulation: An Up-Down Sequential Allocation Study

Abstract

Purpose: This study aimed to observe the effect of bilateral transverse abdominis plane (TAP) block on the MACBAR of sevoflurane in gynecological patients with laparoscopic pneumoperitoneal stimulation. Patients and Methods: Fifty patients who underwent laparoscopic surgery were randomly assigned to either the control group (n= 25) or the TAP block group (n= 25). Patients in the TAP block group were subjected to a bilateral transversal abdominal muscle plane block with 0.33% ropivacaine (20 mL on each side) guided by ultrasound. The control group received an equal volume of normal saline. The MACBAR of sevoflurane in each group was determined using a sequential allocation technique. Results: The MACBAR of sevoflurane in the TAP block group was significantly lower than that in the control group (4.20% [95% confidence interval {CI}, 4.02%–4.38%] vs 5.03% [95% CI, 4.89%–5.18%]). Conclusion: Bilateral TAP block can reduce the MACBAR of sevoflurane in gynecological patients with pneumoperitoneum stimulation. Trial Registration Number: ChiCTR2100046517. The trial is publicly available and registered at www.chictr.org.cn on May 18, 2021.