Disturbances in the function of cardiovascular system in patients following endotracheal intubation and attempts of their prevention by pharmacological bloackade of sympathetic system.

The author recorded arterial blood pressure by direct method and ECG in 94 patients during laryngoscopy and intubation. A rise of the mean arterial blood pressure was observed from 104 to 153 mm Hg together with the appearance of ventricular premature beats in patients with normal arterial blood pressure and without arhythmia before the procedure. Superficial analgesia of the pharynx, larynx and trachea failed to prevent the rise of arterial pressure during intubation. The procedure of superficial analgesia connected with intubation caused also a rise in the arterial blood pressure and arrhythmia. Blockade of beta adrenergic receptors reduced the intensity of these disturbances, while blockade of alpha adrenergic receptors increased them. Blockade of the sympathetic ganglia by controlled infusion of trimethaphan (Arfonad) allowed the arterial pressure to be controlled during intubation thus preventing sudden rises and the development of arrhythmia. The author suggests that a sudden rise in the arterial blood pressure during endotracheal intubation may cause rupture of aortic or intracranial aneurysms. The rise of arterial blood pressure precedes the appearance of ventricular premature beats caused by stimulation of the pharynx, larynx and trachea.