[Bolus administration of esmolol for preventing the haemodynamic response to tracheal intubation: a multicentre clinical study].

OBJECTIVE: To explore the dose-response relation and the safety of esmolol administered as a single i.v. bolus prior to the induction of anesthesia for preventing the haemodynamic response to tracheal intubation.

METHODS: 1,830 patients from 20 centres were randomly divided into three groups: E1 group, receiving esmolol at a dose of 1 mg/kg; E2 group, at 2 mg/kg and E0 group, receiving 0.9% NaCl. Heart rate, systolic and diastolic, and mean artery blood pressures (MAP) were measured following the induction and 1 to 10 minutes following the intubation.

RESULTS: The patients in the E0 group had greater HR and MAP values after anesthesia induction and tracheal intubation than the patients in the E1 and E2 groups (P < 0.05-0.01). The E1 group had higher HR than the E2 group (P < 0.05-0.01). The incidence of tachycardia after intubation was higher in the E0 group (63.8%) than in the E1 group (34.7%) and the E2 group (22.6%) (P < 0.01). The proportion of hypotention and bradycardia was higher in the two treatment groups than the E0 group (P < 0.01), but no severe adverse event was observed.

CONCLUSION: A 1-2 mg/kg bolus of esmolol is effective and safe for preventing the haemodynamic response to tracheal intubation. The clinical and side-effects are all dose-related.