Laryngeal mask insertion using thiopental and low dose atracurium: a comparison with propofol

To compare the laryngeal mask airway (LMA) insertion conditions produced by propofol and a thiopental - low dose atracurium combination.

In a randomized controlled double blind study, 120 premedicated patients were allocated into four groups. After pre-oxygenation, anesthesia was induced as follows: 1 microg x kg(-1) fentanyl, 2.5 mg x kg(-1) propofol (group I); 1 microg x kg(-1) fentanyl, 5 mg x kg(-1) thiopental (group II); 1 microg x kg(-1) fentanyl, 5 mg x kg(-1) thiopental, 0.05 mg x kg(-1) or 0.1 mg x kg(-1) atracurium (groups III and IV respectively). The LMA was inserted by a blinded anesthesiologist who also assessed the following insertion conditions on a three point scale; jaw relaxation, biting, gagging, coughing, presence of laryngospasm, adequacy of airway patency, number of attempts at insertion and overall insertion conditions.

There was no difference in insertion conditions between groups I, III and IV. Group II produced the worst overall conditions (P<0.05). There were no differences in hemodynamic changes and apnea times between all four groups.

The combination of fentanyl-thiopental with low dose atracurium (0.05 or 0.1 mg x kg(-1)) provided conditions comparable with those of propofol for LMA insertion.