The opioid-sparing effect of intraoperative superior hypogastric plexus block after total abdominal hysterectomy: A randomized controlled trial

Abstract Background: Postoperative pain is a common concern for patients undergoing total abdominal hysterectomy (TAH). A significant amount of opioid analgesic is typically necessary to effectively manage pain after a TAH, despite the potential for experiencing side effects. Therefore, the use of any technique that will provide an opioid-sparing effect is highly desirable. This research investigated the postoperative opioid-sparing effects of superior hypogastric plexus block (SHPB) with bupivacaine versus a placebo in patients undergoing TAH. Materials and Methods: A randomized, double-blinded, placebo-controlled study was conducted over nine months. Fifty-four consenting participants were randomized into Groups A and B to receive SHPB with bupivacaine or saline, respectively. The opioid-sparing effect was determined by the total postoperative morphine consumption in 24 h in both groups. The analysis of data was conducted using version 23.0 of the Statistical Package for the Social Sciences (IBM-SPSS). Results: Patient ages in the study ranged from 35 to 65 years. The average age of participants in both Group A (51.70 ± 9.37) and Group B (51.89 ± 9.68) was comparable, with a P value of 0.943. Group A showed significantly lower postoperative pain scores, as measured by the visual analog scale, at the post-anesthesia care unit and at 1, 2, and 4 h ( P < 0.05). Group A demonstrated a prolonged time to the first analgesic request compared with the control group ( P < 0.001). Postoperative morphine consumption was significantly lower in Group A, with a mean consumption of 24.03 ± 2.83 mg, compared with 34.24 ± 4.67 mg in Group B ( P < 0.001). In Group A, eight (29.6%) patients had nausea, while 17 patients (63.0%) had nausea in Group B ( P = 0.028). In Group A, four patients (14.8%) experienced vomiting, while in Group B, 14 patients (51.9%) experienced vomiting. The patients in both groups were comparable in the incidence of pruritus ( P = 1.000). The complications related to SHPB or bupivacaine were not recorded in this study. Conclusion: The study showed that intraoperative SHPB using bupivacaine provided a better opioid-sparing effect when compared with a placebo.