EFFECTS OF TRIMETAPHAN ON THE CARDIOVASCULAR RESPONSE TO TRACHEAL INTUBATION

In three groups of 10 patients, we have studied the effect onthe cardiovascular responses to laryngoscopy and intubationof bolus doses of saline or trimetaphan 0.05 mg kg^–1 or0.1 mg kg^–1 given 1.75 min before the start of laryngoscopy.Anaesthesia was induced with thiopentone 5 mg kg^–1 i.v.and tracheal intubation was facilitated with vecuronium 0.2mg kg^–1. During anaesthesia, ventilation was assistedor controlled with 1% enflurane and 50% nitrous oxide in oxygen.Patients receiving saline showed a significant increase in meanarterial pressure and rate-pressure product associated withtracheal intubation. These increases following tracheal intubationwere less in trimetaphan-treated patients compared with thoseof the control group (P<0.05). There was no significant differencein heart rate following tracheal intubation between the threegroups. These data suggest that trimetaphan may be used as asupplement during induction, to attenuate the hypertensive responseassociated with laryngoscopy and tracheal intubation.