Liquid paraffin is superior to 2% lidocaine gel in reducing urethral pain during Urodynamic study in men: A pilot study

Aims: To compare the pain perception between intraurethral instillation of 2% lidocaine gel and liquid paraffin during Urodynamic study in men. Methods: A randomized, single-blind comparison trial was conducted. Forty men scheduled to undergo multichannel Urodynamic study were randomized to receive either 10 ml of 2% lidocaine gel (group 1, n = 20) or 10 ml of liquid paraffin (group 2, n = 20). Patients recorded their pain on a 0-10 visual analog scale prior to lubricant instillation, immediately after lubricant instillation, after the introduction of the Urodynamic catheter, 5 and 30 min after the catheter was taken out. Results: pain scores were significantly higher in group 1 compared to group 2 immediately after the instillation of the lubricants (4.2 ± 1.5 vs. 2.6 ± 0.9, P < 0.001) and after catheterization (4.8 ± 1.5 vs. 3.5 ± 1.1, P < 0.01). There were no differences in the pain scores between the two groups in the other time points that were evaluated. Conclusions: Liquid paraffin is more efficient than 2% lidocaine gel in reducing urethral pain during Urodynamic study in men. Pain scores were specifically better during the instillation of the lubricant and during the delivery of the urethral catheter.