Topical Analgesia with Lidocaine Plus Diclofenac Decreases Pain in Benign Anorectal Surgery: Randomized, Double-blind, and Controlled Clinical Trial

Objective: The aim of this study is to evaluate the efficacy and safety of a topical formulation containing lidocaine plus diclofenac (CLIFE1) compared to CLIFE2 (lidocaine), to decrease pain in benign anorectal surgery (BARS) to date not evaluated. Background: More than 50% of patients undergoing BARS, especially hemorrhoidectomy, suffer from moderate and severe postoperative pain. This remains an unresolved problem that could be addressed with the new CLIFE1 topical treatment. Methods: A multicenter, randomized double-blind, active-controlled parallel-group superiority trial, was conducted in two Spanish hospitals. Patients undergoing BARS (hemorrhoids, anal fistula and anal fissure) were randomized at the end of surgery at a 1:1 ratio to receive first dose either CLIFE1 (n=60) or CLIFE2 (n=60) anorectal topical treatment, and after every 12 hours for the first three postoperative days and once a day from the fourth to sixth. The primary outcome was average of pain decrease after topical treatment, measured with visual analogue scale (VAS) by the patients themselves, the evening in the surgery day and four times daily for the first three postoperative days. Results: The results of 120 patients included out of 150 selected undergoing BARS show a decrease in pain after CLIFE1 topical treatment (7.47±13.2) greater than with CLIFE2 (4.38±6.75), difference -3.21 (95% CI) -5.75; -0.676; p=0.008), decreasing significantly postoperative pain (≥ 9 mm, VAS) in 35% of patients undergoing benign anorectal surgery, compared to 18.33 % treated with lidocaine. Conclusions: The CLIFE1 topical treatment shows better analgesic efficacy than CLIFE2 in BARS