title: The effect of a 3 : 1 volume mixture of propofol 1% and thiopental 2.5% in reducing the pain on injection of propofol in children.
abstract: BACKGROUND
  In this prospective, randomized, double-blind, controlled trial, our primary objective was to assess the effect of a 3 : 1 mixture of propofol and thiopental in reducing pain on injection in children. Our hypothesis was that a 3 : 1 mixture of propofol and thiopental (treatment) would reduce the incidence of pain on injection to 20% compared to the expected incidence of 40% in the control group of an 11 : 1 mixture of propofol and 2% lidocaine.
  
  
  METHODS
  Study subjects were patients 12-17 years old who were scheduled to undergo surgery and general anesthesia. Pain was assessed by a single-blinded observer present in the operating room. The major statistical method used in the analysis was multiple logistic regression.
  
  
  RESULTS
  Among the 164 children analyzed, 96 patients (58.5%) were male. The average age was 14.3 (sd = 1.65). The incidence of pain in the control group was 32.1% (26/81), compared to 25.3% (21/83) in the treatment group. The logistic regression analysis showed that there was not sufficient evidence that the treatment group was better than control group in reducing pain (P = 0.24). There were no significant differences in postoperative recovery time, nausea, vomiting, or blood pressure between the two groups (all P values >0.10).
  
  
  CONCLUSIONS
  There was not sufficient evidence to show that a 3 : 1 mixture of propofol and thiopental was better than an 11 : 1 volume admixture of propofol and lidocaine in reducing the incidence of pain on injection to 20%.
authors.affiliation: Nemours Children's Clinic, Jacksonville, FL 32207, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Fahringer
authors.forename: Salvatore R
authors.initials: SR
authors.lastname: Goodwin
authors.forename: Mary K
authors.initials: MK
authors.lastname: Warde
authors.forename: Gang
authors.initials: G
authors.lastname: Ye
authors.forename: Bryan
authors.initials: B
authors.lastname: Blackwelder
authors.forename: Adebisi M
authors.initials: AM
authors.lastname: Ajala
authors.forename: Fahmy S
authors.initials: FS
authors.lastname: Gurgis
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000465:Algorithms; D019162:Anesthetics, Combined; D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000009:adverse effects*; D001794:Blood Pressure / Q000187:drug effects; D002648:Child; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006993:Hypnotics and Sedatives; D007275:Injections, Intravenous; D016015:Logistic Models; D008297:Male; D008874:Midazolam; D016017:Odds Ratio; D010146:Pain / Q000139:chemically induced* / Q000453:epidemiology / Q000517:prevention & control*; D010147:Pain Measurement; D011229:Preanesthetic Medication; D015742:Propofol / Q000008:administration & dosage / Q000009:adverse effects*; D011446:Prospective Studies; D018401:Sample Size; D013874:Thiopental
chemical_list: D019162:Anesthetics, Combined; D018686:Anesthetics, Intravenous; D006993:Hypnotics and Sedatives; D013874:Thiopental; D008874:Midazolam; D015742:Propofol