Effects of Diazoxide on the Cardiovascular Response to Tracheal Intubation

The efficacy of 2 or 3 mg/kg diazoxide given 2.5 min before laryngoscopy in attenuating the cardiovascular responses to laryngoscopy and intubation was studied in 30 patients undergoing elective surgery. Data were compared with those from 10 control patients receiving saline. Anaesthesia was induced using 5 mg/kg thiopentone given intravenously and tracheal intubation was facilitated with 0.2 mg/kg vecuronium bromide. Patients receiving saline showed a significant increase in mean arterial pressure and rate-pressure product associated with tracheal intubation. The increases following tracheal intubation were significantly reduced (P less than 0.05) in diazoxide-treated patients compared with those in the control group, but there were no significant differences in heart rate following tracheal intubation among the three groups. Data suggest that diazoxide can be used as a supplement during induction of anaesthesia to attenuate the hypertensive response associated with laryngoscopy and tracheal intubation.