Nitrous Oxide Reduces Pain Associated With Local Anesthetic Injections
Matthew J Lin1, Danielle P Dubin1, Hooman Khorasani1
1Division of Dermatologic Surgery, Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
Background:
Local anesthetic injections can be painful and distressing.
Objective:
The aim of this study was to determine whether nitrous oxide, ice, vibration, or topical anesthetic improves analgesia for local anesthetic injections.
Method:
A cohort study of 400 patients undergoing Mohs micrographic surgery with local anesthetic was conducted. Patients received no intervention (n = 200), ice (n = 50), topical anesthetic cream (n = 50), vibration device (n = 50), or nitrous oxide (n = 50). Pain was rated using the Visual Analogue Scale (VAS) and Wong-Baker FACES Pain Rating Scale.
Results:
Without intervention, mean VAS was 4.2 and FACES was 4.6. Nitrous oxide was the most successful in reducing pain (mean VAS 1.6 vs. 4.2, P < .01, FACES 1.2 vs. 4.6, P < .01). Topical ice reduced pain (mean VAS 3.0 vs. 4.2, P < .01, FACES 3.0 vs. 4.6, P < .01). Vibration reduced pain (mean VAS 3.5 vs. 4.2, P < .01, FACES 3.6 vs. 4.6, P < .01). Higher pain scores were associated with age <50 (P = .02), male sex (P = .05), and surgery on the nose, lip, ear, or eyelid (P = .02).
Conclusion:
Nitrous oxide, ice, and vibration reduce injection pain. These interventions are especially useful for younger males undergoing surgery on the nose, lip, ear, or eyelid.
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