BUFFERED VERSUS PLAIN LIDOCAINE FOR DIGITAL NERVE BLOCKS

Study objectives: To test whether buffered lidocaine is less painful to administer as a digital nerve block than plain lidocaine. Design: Randomized, double-blind, prospective clinical trial. Setting: University hospital emergency department. Participants: Adults not allergic to lidocaine requiring a digital nerve block. Interventions: Subjects received digital nerve blocks by injection of buffered lidocaine on one side and plain lidocaine on the other in a predetermined, randomized order. Pain of infiltration was assessed. Scores were compared using a two-tailed t-test. Standard 1% lidocaine was used if additional anesthetic was required. Measurements and main results: Thirty-one patients were enrolled. Buffered lidocaine was significantly less painful to administer than plain lidocaine (P<.001; t=4.21). Supplemental anesthesia was required less often for buffered lidocaine (two times) compared with plain lidocaine (six times), although this difference was not statistically significant. Conclusion: Because it causes less pain and is equally efficacious, buffered lidocaine is preferable to plain lidocaine for digital nerve blocks in adults.