COMPARISON OF PLAIN, WARMED, AND BUFFERED LIDOCAINE FOR ANESTHESIA OFTRAUMATIC WOUNDS

Study objective: To compare pain on infiltration, need for additional anesthesia, and pain on suturing in patients given plain, warm, and bu ffered lidocaine preparations before the suturing of traumatic wounds in the emergency department. Design: Randomized, prospective, single-b linded convenience sample. Setting: University hospital ED. Participan ts: Patients with traumatic lacerations. Patients allergic to lidocain e and patients with abnormal mental status or altered pain sensorium w ere excluded. Interventions: All wounds were anesthetized by use of a standard injection technique. Wound margins were anesthetized with pla in, buffered, or warm lidocaine in a randomized fashion. Pain of infil tration was recorded for each margin by means of a previously validate d visual-analogue pain scale. Results: The main outcome parameter was pain of infiltration. Need for additional anesthesia and pain on sutur ing were secondary outcome parameters. We evaluated 45 patients. Pain on injection varied by the type of lidocaine (mean pain scores: plain, 8.2; buffered, 4.7 [P<.05 versus plain], warm, 4.9 [P<.05 versus plai n]). There was no significant difference between the mean pain scores of the groups given warm and buffered lidocaine (P=NS). Need for addit ional anesthesia and pain on suturing did not vary by the type of anes thesia. The order of injection was not found to influence results. Mea n pain scores were not different for margins 1 and 2 in any of the gro ups (P=NS). Conclusion: Both buffered and warmed lidocaine were as eff icacious as plain lidocaine, and they had significantly less pain asso ciated with infiltration than did plain lidocaine. In EDs with fluid w armers, warmed lidocaine may be the most convenient, well-tolerated, e fficacious lidocaine preparation for anesthesia of traumatic wounds.