Intravenous infusion of propofol for induction and maintenance of anaesthesia during endoscopic carbon dioxide laser ENT procedures with high frequency jet ventilation.

Fourteen patients of ASA grades 1-3 were anaesthetised with continuous infusions of propofol and alfentanil for endoscopic carbon dioxide laser ENT microsurgery. Their lungs were ventilated with an oxygen-air mixture using a high frequency jet ventilator. Propofol was given at an initial rate of 120 micrograms/kg/minute for 10 minutes after a bolus dose of 2.6 mg/kg, and then at 80 micrograms/kg/minute. Alfentanil was given at a rate of 0.5 micrograms/kg/minute. Arterial pressure decreased significantly after the bolus dose. It increased significantly for a few minutes after laryngoscopy and returned to baseline values during maintenance of anaesthesia. Heart rate increased significantly during induction and until laryngoscopy was performed but it decreased below its initial value after 5 minutes of maintenance. Platelet count and the degree of aggregation did not change during infusion of propofol.