Comparison of two bolus doses of esmolol for attenuation of haemodynamic response to tracheal intubation.

This prospective study was designed to compare the effectiveness of esmolol (either 100 mg or 200 mg) with a placebo in blunting the haemodynamic response to laryngoscopy and intubation. Seventy-five patients of ASA I or II scheduled for routine-surgery were selected and entered into a placebo-controlled study. Patients were randomly allocated to receive placebo, 100 mg or 200 mg of esmolol IV as part of an anaesthetic induction technique. There were no significant differences in the demographic distribution of the patients in the study. There was no statistical difference in the baseline heart rate (HR) and systolic blood pressure (SBP) between the three groups. One minute after the administration of the drug (prior to intubation) the differences in HR between the placebo group and both the 100 mg and 200 mg groups were significant (p < 0.05), and also at 1 min and 2 min following intubation for the 200 mg group (p < 0.05). In the 200 mg group there was a significant decrease, compared with placebo, in SBP at 1 min (p < 0.05) and at 2 min (p < 0.05) after intubation. In this study, adequate haemodynamic control following was obtained with the administration of 200 mg of esmolol.