Lidocaine jelly and plain aqueous gel for urethral straight catheterization and the Q-tip test: a randomized controlled trial.

OBJECTIVE: To compare the pain perception between lidocaine and plain aqueous gel during assessment of postvoid residual volume and the Q-tip test. METHODS: : Patients were randomly assigned to either to 2% lidocaine hydrochloride jelly or plain aqueous gel. The allocated gel was first used to lubricate a catheter that was inserted into the bladder to measure the postvoid residual volume. After removal of the catheter, a cotton swab, coated with the same allocated gel, was advanced to the urethrovesical junction until resistance was felt. The angle of the swab with the horizontal plane was measured at rest and with Valsalva maneuver. Relevant baseline characteristics and the Wong-Baker FACES pain scores (where 0 is for no pain and 5 for worst pain) were compared. RESULTS: After randomization, lidocaine and the plain aqueous gel arms consisted of 69 and 68 women, respectively. Baseline characteristics of the groups were similar. Significantly fewer women in the lidocaine group (62.3%) reported any pain than those allocated to plain aqueous gel (80.9%) (odds ratio 0.39, 95% confidence interval 0.18-0.85). The median pain score was significantly lower in the lidocaine group (1, range 0-5) compared with 2 (range 0-4), P<.001). CONCLUSION: When compared with plain aqueous gel, 2% lidocaine jelly significantly reduces pain perception during evaluation of postvoid residual volume and the Q-tip test. LEVEL OF EVIDENCE: I.