[Comparison of propofol and pentazocine combined with thiamylal for laryngeal mask insertion].

We evaluated the combination of pentazocine and thiamylal as induction agents for laryngeal mask airway (LMA) insertion and compared this with propofol. Ninety-four patients, ASA grade 1 or 2, were randomly assigned to one of four induction groups as follows; group P: propofol 2.5 mg.kg-1, group p 0.3: pentazocine 0.3 mg.kg-1 followed by thiamylal 5 mg.kg-1, group p 0.6: pentazocine 0.6 mg.kg-1 followed by thiamylal 5 mg.kg-1, and group T: thiamylal 5 mg.kg-1. In group T (n = 5), insertion of LMA was impossible due to inadequate anesthesia. In contrast, good and acceptable conditions for LMA insertion were obtained in 85.2%, 86.7%, and 96.9% of group P, p 0.3, and p 0.6, respectively. Apneic interval, endtidal CO2 and arterial CO2 were significantly greater in pentazocine groups than in propofol group (group P < p 0.3 < p 0.6). Systolic pressure decreased after induction in all groups. Decreases in systolic and diastolic pressure were significantly greater in group P. Heart rate did not show any significant change. We conclude that the induction with the combination of pentazocine and thiamylal provides suitable conditions for LMA insertion with more stable hemodynamics compared with propofol. Doses of 0.3 mg.kg-1 seem to be desirable for LMA insertion.