Efficacy and safety of pudendal nerve block for postoperative analgesia of hemorrhoids: a systematic review of 7 randomized controlled trials

Abstract

Pudendal nerve block (PNB) is one of the common anesthesia methods, which has been widely applied in postoperative analgesia of hemorrhoids in recent years. To analyze the effectiveness and safety of PNB on postoperative analgesia of hemorrhoids, we conducted a systematic review of 7 randomized controlled trials (RCT) searched from PubMed, Embase, Web of Science, the Cochrane Central Register of Controlled Trials (CENTRAL), the China Network Knowledge Infrastructure (CNKI), the Wan Fang Database and Chinese Biomedicine (CBM), which were published before 7th September, 2020, and involved a total of 560 participants. We evaluated the function of PNB in improving outcomes of postoperative analgesia of hemorrhoids. Visual analogue scale (VAS) scores on postoperative 6, 12, 24, 48 h and the first time of defecation were enhanced by the application of PNB. The incidence of urinary retention, the need for analgesics [odds ratio (OR), 0.11; 95% CI, 0.04-0.37; P=0.0003] and the incidence of side effects (OR, 0.12; 95% CI, 0.04-0.39; P=0.004) in patients receiving PNB were lower than those of controls. In addition, there was no significant difference in the incidence of bleeding between groups. PNB could effectively relieve postoperative pain of hemorrhoids and reduce complications without increasing the incidence of side effects. Our results still need to be confirmed by high-quality, multi-center clinical studies.

The role of pudendal nerve block in hemorrhoid surgery: a systematic review and meta-analysis of double-blind randomized controlled trials

“…A meta-analysis not only confirmed the highly beneficial safety of PNBs but also showed that the incidence of nausea and vomiting were significantly reduced ( 10 ). PNBs were also reported to reduce the incidence of urinary retention ( 11 ), which is a relatively common complication after hemorrhoid surgery that may hinder outpatient treatment.…”

“…Multiple randomized trials have been published on PNBs, confirming a longer analgesic duration and lower incidence of complications compared with the abovementioned drugs ( 8 , 9 ). Although some systematic reviews and meta-analyses support the analgesic effect of PNBs in hemorrhoid surgery ( 10 , 11 ), most of them are based on low-quality research data.…”

Local anaesthetic infiltration in rubber band ligation of rectal haemorrhoids: study protocol for a three-arm, double-blind randomised controlled trial (PLATIPUS trial)

“…Results from a recent comparative cohort study by Behrenbruch et al suggest that submucosal LA reduces periprocedural analgesic requirement and time to discharge, however, this study was not randomised and may have been subject to bias 12. PNB is well researched in the context of surgical haemorrhoidectomy, and is considered best practice,13 14 but its efficacy in RBL has not been examined.…”

Analgesic effect of local anaesthetic in haemorrhoid banding: systematic review and meta-analysis

“…The review of four randomised controlled trials did not look at surrogate measures of post-procedural pain such as analgesia use and time-to-discharge and was limited by the small sample sizes and heterogeneity of included trials. Additionally, although several meta-analyses have studied the efficacy of PNB in haemorrhoidectomies [ 11 , 12 ], no reviews have included participants who have received a PNB for RBL. There is a need for high-quality research to standardize and optimise analgesia in patients undergoing this common procedure.…”