Chlorhexidine in urethral gel: does it cause pain at flexible cystoscopy?

To investigate the effect of chlorhexidine gluconate in urethral local anesthetic gel on patients undergoing outpatient flexible cystoscopy. We postulated that chlorhexidine was contributing to the pain and urgency that occurs during and after cystoscopy.

A prospective randomized single-blinded study was conducted. A total of 141 patients undergoing outpatient flexible cystoscopy participated in the study. They were randomized to receive 10 mL of 2% lignocaine gel with 0.05% chlorhexidine gluconate (group 1, n = 72) or 10 mL of 2% lignocaine and aqueous gel mixture (group 2, n = 69). Pain scores were recorded on a numerical visual analog scale from 0 to 10.

The groups were well matched for the purposes of comparison. The mean pain scores were not significantly different between groups 1 and 2 at the insertion of the scope (2.1 versus 2.2, P = 0.7), during cystoscopy (1.8 versus 1.9, P = 0.759), and immediately after cystoscopy (1.4 versus 0.8, P = 0.06). However, a significant difference was found in the mean pain scores between groups 1 and 2 during the first void (1.8 versus 1.0, P = 0.031) and after the first void (2.4 versus 1.2, P = 0.007). A significant increase occurred in the reported levels of urgency after cystoscopy in group 1 (P = 0.018). No difference was found in the level of culture-proven symptomatic infection.

Chlorhexidine appears to contribute to significant levels of pain and urgency after outpatient flexible cystoscopy.