Pudendal Nerve Block in Hemorrhoid Surgery: A Systematic Review and Meta-analysis.

Abstract

Postoperative pain represents an important issue in traditional hemorrhoidectomy. Optimal pain control is mandatory, especially in a surgical day care setting. The aim of this study was to investigate the use of pudendal nerve block in patients undergoing hemorrhoidectomy. PubMed, Google Scholar, Cochrane Library, and Web of Science databases were searched up to December 2020. Randomized trials evaluating the pudendal nerve block effect in patients undergoing hemorrhoidectomy were selected. Hemorrhoidectomy under general or spinal anesthesia with or without pudendal nerve block was performed. Opioid consumption, pain on the visual analogue scale, length of hospital stay, and readmission rate were the main outcomes of interest and were plotted by using a random-effects model. The literature search revealed 749 articles, of which 14 were deemed eligible. A total of 1214 patients were included, of whom 565 received the pudendal nerve block. After hemorrhoidectomy, patients in the pudendal nerve block group received opioids less frequently (relative risk, 0.364; 95% CI, 0.292-0.454, p < 0.001) and in a lower cumulative dose (standardized mean difference, -0.935; 95% CI, -1.280 to -0.591, p < 0.001). Moreover, these patients experienced less pain at 24 hours (standardized mean difference, -1.862; 95% CI, -2.495 to -1.228, p < 0.001), had a shorter length of hospital stay (standardized mean difference, -0.742; 95% CI, -1.145 to -0.338, p < 0.001), and had a lower readmission rate (relative risk, 0.239; 95% CI, 0.062-0.916, p = 0.037). Sensitivity analysis excluded the occurrence of publication bias on the primary end point, and the overall evidence quality was judged "high." Occurrence of publication bias among some secondary end points and heterogeneity are the main limitations of this study. This systematic review and meta-analysis show significant advantages of pudendal nerve block use. A reduction in opioid consumption, postoperative pain, complications, and length of stay can be demonstrated. Despite the limitations, pudendal nerve block in patients undergoing hemorrhoidectomy should be considered.