title: Effect of tracheal lidocaine on intubating conditions during propofol-remifentanil target-controlled infusion without neuromuscular blockade in day-case anesthesia.
abstract: BACKGROUND
  Lidocaine is a useful intravenous and topical adjunct to facilitate tracheal intubation. We evaluated the effect of tracheal lidocaine on tracheal intubating conditions without neuromuscular blocking agent and hemodynamics during anesthesia induction with propofol and remifentanil target-controlled infusion (TCI).
  
  
  METHODS
  Fifty patients, aged 18-60 years, scheduled for closed reduction of fractured nasal bone were randomly assigned to the control group (n = 25) or lidocaine group (n = 25). Anesthesia was induced with propofol-remifentanil TCI with the effect-site concentration of 5 µg/ml and 5 ng/ml. Four minutes after the start of propofol-remifentanil TCI, 4% lidocaine or saline 3 ml was instilled to larynx and trachea, and intubation was performed 1 min later. Acceptable intubation was defined as excellent or good intubating conditions. Hemodynamic data, induction and recovery profiles were recorded.
  
  
  RESULTS
  Intubating condition was clinically acceptable in 13 out of 25 (52%) patients in the control group and in 22 out of 25 (88%) in the lidocaine group, and there was a significant difference between the two groups in regard to acceptable intubating conditions (P = 0.005). Mean arterial pressure change over time was significantly different between the two groups. There were no significant differences in the heart rate between the two groups.
  
  
  CONCLUSIONS
  This study demonstrated that laryngotracheal administration of 4% lidocaine could increase the percentage of acceptable conditions for tracheal intubation during propofol and remifentanil anesthesia without neuromuscular blockade.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Jin-Soo
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Dae-Hee
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Han Bum
authors.initials: HB
authors.lastname: Joe
authors.affiliation: Department of Anesthesiology and Pain Medicine, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Chang Keun
authors.initials: CK
authors.lastname: Oh
authors.affiliation: Department of Anesthesiology and Pain Medicine, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Jong-Yeop
authors.initials: JY
authors.lastname: Kim
keywords: Intravenous anesthesia; Intubation; Lidocaine