A prospective, randomized, double-blind study comparing lignocaine gel and plain lubricating gel in relieving pain during flexible cystoscopy.

Abstract

To determine the optimum duration for the retention of 2% lignocaine gel intraurethrally as an anaesthetic for flexible cystoscopy in men. A prospective, randomized, double-blind, placebo-controlled trial was conducted in two parts. Initially, the importance of duration was determined, i.e. whether pain relief was significantly improved when lignocaine gel was instilled for longer than is currently practised. As pain relief was improved by retaining the lignocaine gel for longer, the optimum time was determined in a second trial. Initially, 90 patients were divided into four groups receiving 20 mL of 2% lignocaine gel or plain lubricating gel for 5 or 25 min. Subsequently, 60 men were divided into two groups receiving 20 ml of 2% lignocaine gel for 15 or 25 min. The patients' discomfort was recorded using a 4-point descriptive pain scale and a 100 mm non-graphical visual analogue scale. In the first study, those patients receiving lignocaine gel for 25 min experienced significantly less pain than the other three groups. In the second, lignocaine gel in the urethra for 15 min provided the same level of pain relief as lignocaine for 25 min. Pain during flexible cystoscopy can be significantly reduced when 20 mL of 2% lignocaine gel is left in the urethra for 15 min; lignocaine gel would be more effective when left for longer than is currently practised.