The Effects of Pudendal Block in Voiding Complication after Anal Surgery

ABSTRACT

Urinary retention in common benign anal surgery is a burden to ambulatory surgery. PURPOSE: To reduce voiding complication pudendal nerve block (PB) was applied in hemorrhoids surgery. METHODS: We compared PB with spinal anesthesia (SA) for anal surgery. In this prospective study, 163 patients undergoing elective hemorrhoids surgery by single surgeon were randomized to receive either PB with 0.5% bupivacaine (n=81) with 1: 20,000 epinephrine or SA with 0.5% bupivacaine (n=83). RESULTS: There were no statistically significant differences in patient demographics, total amount of administered fluid, time to onset of block, or intraoperative pain. All patients had a successful block for surgery however, puborectalis muscle relaxation with PB was not complete. The time from injection of the anesthetics to first development of pain was longer in the patients who received PB (9.1 vs 3.1h; P<0.001). Urinary catheterization needed in only 6 patients in PB group compared with 57 cases in SA group (p<0.001). Degree of pain was significantly low in PB (2.7 vs 5.2 with VAS; p<0.001) Injected analgesics was significantly reduced in PB (16/81 vs 45/82; p<0.001) CONCLUSIONS: Our results suggest that PB with bupivacaine results in fewer postoperative voiding complications and less pain compared with traditional SA in hemorrhoidectomy.