Original contribution Does lidocaine more effectively prevent pain upon induction with propofol or etomidate when given preemptively than when mixed with the drug? Margaret F. Brock MD (Assistant Professor of Anesthesiology) , Brian E. Grace MD (Anesthesiology Resident), Benjamin Morley MD (Fourth-year Medical Student), Gabe Hillegass MD (Fourth-year Medical Student), Timothy T. Houle PhD (Research Assistant Professor and Biostatistician), Leanne Groban MD (Associate Professor of Anesthesiology) Department of Anesthesiology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1009, USA Received 3 December 2008; revised 2 November 2009; accepted 15 November 2009 Keywords: Anesthesia induction pain; Drug delivery: Timing; Etomidate; Injection pain; Lidocaine; Propofol Abstract Study Objective: To compare the efficacy of 2% lidocaine timingon alleviation of pain upon induction using propofol or etomidate. Design: Prospective, randomized, double-blinded study. Setting: Academic teaching hospital. Patients: 80 adult, ASA physical status I, II, and III patients scheduled for elective outpatient or inpatient surgery with an intravenous induction agent. Interventions: Patients were randomly assigned to two groups. Group A received preemptive saline 4 mL and lidocaine 4 mL mixed with either propofol 20 mL (n = 20) or etomidate 20 mL (n = 20). Group B received preemptive lidocaine 4 mL and saline 4 mL mixed with either propofol 20 mL (n = 20) or etomidate 20 mL (n = 20). The 4 mL dose of preemptive drug dwelled for three minutes. Measurements: The induction drug mixture was injected over 60 seconds while the patient was assessed for pain using a 4-point scale (0 = no pain,1 = mild, 2 = moderate, and 3 = severe). Main Results: Mean induction pain scores were 1.0 (SD = 0.89) for propofol and 0.9 (SD = 0.90) for etomidate, representing mild induction pain. Mean induction pain scores were 0.93 (SD = 0.92) for the simultaneous treatment groups and 0.98 (SD = 0.87) for the preemptive treatment groups. The observed differences in pain scores between the techniques were not statistically (P N 0.62) or clinically meaningful. Conclusions: Alleviation and intensity of post-injection pain were not significantly influenced by the timingof administration of lidocaine 80 mg or by the specific induction drug. Pre-lidocaine and simultaneouslidocaine with either propofol or etomidate prevented severe pain in 95% of patients. © 2010 Elsevier Inc. All rights reserved. Corresponding author. Tel.: +1 336 716 4498; fax: +1 336 716 8190. E-mail address: mbrock@wfubmc.edu (M.F. Brock). 0952-8180/$ see front matter © 2010 Elsevier Inc. All rights reserved. doi:10.1016/j.jclinane.2009.11.004 Journal of Clinical Anesthesia (2010) 22, 505509