Attenuation of cardiovascular responses to tracheal extubation: comparison of verapamil, lidocaine, and verapamil-lidocaine combination.

UNLABELLED

We recently showed that verapamil attenuated hemodynamic responses to tracheal extubation. The aim of the current study was to compare the efficacy of a combination of intravenous (I.V.) verapamil (0.1 mg/kg) and I.V. lidocaine (1 mg/kg) with that of each drug alone in suppressing the cardiovascular changes during tracheal extubation and emergence from anesthesia. One hundred adult patients (ASA physical status I) who were to undergo elective minor surgery were randomly assigned to one of four groups (n = 25 each): Group S = saline plus saline (control), Group V = verapamil 0.1 mg/kg I.V. plus saline, Group L = lidocaine 1 mg/kg I.V. plus saline, and Group V-L = verapamil 0.1 mg/kg I.V. plus lidocaine 1 mg/kg I.V. These medications were given 2 min before tracheal extubation. Anesthesia was maintained with 1.0%-2.0% sevoflurane and 60% nitrous oxide (N2O) in oxygen. Muscle relaxation was achieved with vecuronium, and a residual neuromuscular blockade was reversed with neostigmine 0.05 mg/kg (combined with atropine 0.02 mg/kg). Changes in heart rate (HR) and arterial blood pressure (AP) were measured during and after tracheal extubation. In the control group, the HR and systolic and diastolic AP increased significantly during tracheal extubation. Verapamil, lidocaine, and their combination attenuated the increases in these variables. The beneficial effect was the greatest with the combination of verapamil and lidocaine. These findings suggest that verapamil 0.1 mg/kg and lidocaine 1 mg/kg given I.V. concomitantly 2 min before tracheal extubation is a simple and more effective prophylaxis than verapamil or lidocaine alone for attenuating the cardiovascular changes associated with tracheal extubation.

IMPLICATIONS

Tachycardia and hypertension associated with tracheal extubation, which may lead to myocardial ischemia, represent a potential risk for patients with coronary arterial disease. To seek effective pharmacological prophylaxis against these complications, we compared the attenuation of hemodynamic changes among verapamil, lidocaine, and a verapamil/lidocaine combination using ASA physical status I patients and found the combination to be effective.