Circulatory responses to laryngoscopy and endotracheal intubation in patients with and without cardiovascular disease. Effect of prophylactic practolol.

The effect of small intravenous doses of practolol (0.2 mg/kg body weight) on the circulatory response to laryngoscopy and endotracheal intubation, when administered with atropine (0.01 mg/kg b.w.) prior to anaesthesia was studied in 39 patients with and without cardiovascular disease. Practolol diminished significantly the rise of mean arterial pressure and pulse rate affected by laryngoscopy and endotracheal intubation when performed under thiopentone-succinylcholine anaesthesia. Arrhythmias were also less frequent through the statistical significance could not be ascertained in this small series. The small practolol dose used had no adverse circulatory effects. It is suggested that the administration of a small prophylactic dose of practolol is useful in preventing the excessive cardiovascular response due to laryngoscopy and endotracheal intubation.