title: The effect of an intermediate dose of labetalol on heart rate and blood pressure responses to laryngoscopy and intubation.
abstract: OBJECTIVE
  To evaluate the efficacy of an intermediate dose of labetalol (0.4 mg/kg) for attenuation of heart rate (HR) and blood pressure (BP) responses to laryngoscopy and intubation.
  
  
  METHODS
  Randomized, double-blind, placebo-controlled study.
  
  
  METHODS
  Inpatient gynecology service at a university medical center.
  
  
  METHODS
  Two groups of 18 patients each undergoing elective surgery under general anesthesia.
  
  
  METHODS
  Patients received either 0.4 mg/kg of labetalol or an equal volume of normal saline 5 minutes prior to laryngoscopy and intubation.
  
  
  RESULTS
  HR and BP were measured upon arrival in the operating room (OR) (baseline) and at 1 minute intervals thereafter for 4 minutes prior to intubation and through 10 minutes following intubation. The labetalol group had a significantly lower HR from induction through 1 minute following intubation. Intragroup differences in HR were greatest immediately following laryngoscopy and intubation (33% increase above baseline for the placebo group vs 1% for the labetalol group, p less than 0.05). At the same time, a significant increase in mean arterial pressure (MAP) from baseline was noted in both groups (29% for the placebo group vs 23% for the labetalol group), but the difference between the groups was not significant.
  
  
  CONCLUSIONS
  An intermediate dose of labetalol blunted the HR response to laryngoscopy and intubation during rapid-sequence induction in healthy patients but had a minimal effect on BP.
authors.affiliation: Department of Anesthesiology, Yale University School of Medicine, New Haven, CT.
authors.forename: K S
authors.initials: KS
authors.lastname: Chung
authors.forename: R S
authors.initials: RS
authors.lastname: Sinatra
authors.forename: J H
authors.initials: JH
authors.lastname: Chung
mesh_terms: D000328:Adult; D000769:Anesthesia, Inhalation; D000771:Anesthesia, Intravenous; D001794:Blood Pressure / Q000187:drug effects*; D004311:Double-Blind Method; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D007442:Intubation, Intratracheal; D007741:Labetalol / Q000008:administration & dosage / Q000627:therapeutic use*; D007828:Laryngoscopy; D010919:Placebos; D013997:Time Factors
chemical_list: D010919:Placebos; D007741:Labetalol