OBJECTIVE: A lidocaine patch is often used for topical anesthesia prior to venipuncture, but needs to be applied for several hours before the puncture, and the site is fixed. A metered-dose lidocaine pump spray could be used to produce cutaneous topical anesthesia. In this study, we compared the anesthesia between the spray and the patch. DESIGN:Thirteen healthy male volunteers received three treatments of metered-dose 8% lidocaine spray, a lidocaine patch, and no application as control measurement, in a random order separated by at least 2 days. Each treatment was applied topically on the forearm. Sensory nerve fibers (Abeta, Adelta, and C fibers) were evaluated with a series of 5, 250, and 2,000 Hz stimuli using current perception threshold (CPT) before and 30 minutes after each application. RESULTS: Under the control condition, CPTs measured at baseline and at 30 minutes were similar for 2,000 and 250 Hz stimuli, but significantly reduced for 5 Hz stimulation at 30 minutes. Under patch application, CPTs for 2,000 and 250 Hz stimuli at 30 minutes after application were significantly higher than baseline, while CPTs for 5 Hz stimulation at baseline and 30 minutes after application were similar. Under spray application, CPTs for all stimuli at 30 minutes were significantly higher than baseline. CONCLUSIONS: Similar to the lidocaine patch, the lidocaine spray produces cutaneous weak anesthesia at 30 minutes after treatment. The spray seems to produce local anesthesia faster than the patch.
RCT Entities:
OBJECTIVE: A lidocaine patch is often used for topical anesthesia prior to venipuncture, but needs to be applied for several hours before the puncture, and the site is fixed. A metered-dose lidocaine pump spray could be used to produce cutaneous topical anesthesia. In this study, we compared the anesthesia between the spray and the patch. DESIGN: Thirteen healthy male volunteers received three treatments of metered-dose 8% lidocaine spray, a lidocaine patch, and no application as control measurement, in a random order separated by at least 2 days. Each treatment was applied topically on the forearm. Sensory nerve fibers (Abeta, Adelta, and C fibers) were evaluated with a series of 5, 250, and 2,000 Hz stimuli using current perception threshold (CPT) before and 30 minutes after each application. RESULTS: Under the control condition, CPTs measured at baseline and at 30 minutes were similar for 2,000 and 250 Hz stimuli, but significantly reduced for 5 Hz stimulation at 30 minutes. Under patch application, CPTs for 2,000 and 250 Hz stimuli at 30 minutes after application were significantly higher than baseline, while CPTs for 5 Hz stimulation at baseline and 30 minutes after application were similar. Under spray application, CPTs for all stimuli at 30 minutes were significantly higher than baseline. CONCLUSIONS: Similar to the lidocaine patch, the lidocaine spray produces cutaneous weak anesthesia at 30 minutes after treatment. The spray seems to produce local anesthesia faster than the patch.