Ultrasound-guided pudendal nerve block for postoperative pain management in procedures for prolapse and hemorrhoids: a randomized, double-blinded trial.

PURPOSE: The study aimed to evaluate the efficacy of ultrasound-guided pudendal nerve block (PNB) versus local anesthetic infiltration (LAI) in managing the pain.

METHODS

This is a prospective, randomized, double-blinded trial, 78 patients undergoing procedure for prolapse and hemorrhoids (PPH) were randomly allocated to receive either ultrasound-guided PNB or LAI. Primary outcomes were postoperative pain scores using the visual analogue scale at multiple time points within the first 48 h. Secondary outcomes included tramadol consumption, incidence of postoperative nausea and vomiting, and quality of recovery-15 (QoR-15) scores.

RESULTS

The trial ultimately involved 71 patients. Results showed that the PNB group had significantly lower pain scores at 6, 12, and 18 h postoperatively compared with the LAI group (all P < 0.01), with no significant differences noted at 24 and 48 h. PNB group also had fewer patients requiring supplemental tramadol (5/36) than the LAI group (12/35) (P < 0.05) and experienced a delayed onset of pain (13.83 ± 11.21 h vs. 6.94 ± 2.88 h; P < 0.001). Furthermore, the incidence of anal sphincter spasms was lower in the PNB group (5/36) compared with the LAI group (12/35) (P < 0.04). QoR-15 scores at 24 h postoperatively were significantly higher in the PNB group (119.11 ± 5.87) compared with the LAI group (112.03 ± 7.04) (P < 0.05), indicating a better early recovery experience. Patient satisfaction was higher in the PNB group (28/36 vs. 22/35, P < 0.05).

CONCLUSION

Ultrasound-guided PNB was more effective than LAI in pain control and recovery quality. It can be considered an effective method for postoperative pain management in patients undergoing PPH surgery.

TRIAL REGISTRATION: This study was registered with the Chinese Clinical Trial Registry ( https://www.chictr.org.cn/ , Registration No. ChiCTR-IPR-15006427) on May 21st, 2015.