Alfentanil as an adjuvant of balanced anaesthesia for tonsillectomy in adults.

In a double-blind study, 80 adult patients, undergoing tonsillectomy, were randomly allocated to one of the four groups: d-tubocurarine (d-Tc) 50 micrograms/kg+alfentanil (Alf) 20 micrograms/kg, d-Tc 50 micrograms/kg+Alf 50 micrograms/kg, Alf 10 micrograms/kg+Alf 20 micrograms/kg, Alf 10 micrograms/kg+Alf 50 micrograms/kg. The first drug was given 2 min before thiopental and the second drug 1 min before inserting the mouth gag. Intubation was facilitated with suxamethonium. Anaesthesia was maintained with 70% nitrous oxide in oxygen and peripheral muscle relaxation during operation with vecuronium. For analysis of the induction characteristics, both d-Tc-pretreatment groups were treated together and compared with the results of the Alf-pretreatment groups. Muscle fasciculations occurred in 20% in the d-Tc group and in 70% in the Alf group. Neither d-tubocurarine nor alfentanil prevented the cardiovascular intubation response. Cardiovascular responses to the placement of the mouth gag occurred only in the lower-dose alfentanil groups. ECG changes during operation occurred in 25-45% of the patients. The most common ECG change was junctional rhythm. The operating conditions were good in 65-80% of the patients. The mean recovery score (0-10) ranged from 9.3 to 9.7 between the groups. The incidence of nausea ranged from 20-30% and that of vomiting from 10-25% between the groups. Bleeding from the operation site occurred in 20-30% of the patients. None of the patients needed sutures to stop the bleeding.