Double-blind comparison between inverse sequence induction with atracurium and rapid sequence induction with succinylcholine.

In this double-blind randomized study of 60 patients, a new rapid sequence induction technique (RSI), the so-called inverse sequence induction technique (ISI), is compared to the standard RSI using succinylcholine (SUX). All patients were premedicated with midazolam 0.07 mg.kg-1 and morphine 5 mg im. The patients in the ISI group received atracurium 0.6 mg.kg-1 followed after 1 min by thiopental 5 mg.kg-1. The patients in the SUX group were precurarized with atracurium 0.06 mg.kg-1 followed after 3 min by thiopental 5 mg.kg-1 and succinylcholine 1.5 mg.kg-1. In both groups patients were intubated 1 min after thiopental injection by a trained blinded anesthetist who graded intubation conditions from 1 (excellent) to 4 (impossible). Intubation scores (ISI: 1 and SUX: 1 (range 1-3)) and intubation times (from laryngoscopy to cuff inflation: ISI 18 +/- 10 s, SUX 19 +/- 8 s) as well as mean arterial pressure, heart rate, SpO2 and EtCO2 values were not significantly different between groups. Three patients in the ISI group failed to maintain a handgrip. In both groups all patients were able to cough forcefully at the time of thiopental injection. These data emphasize the reliability and safety of ISI as an alternative for RSI when succinylcholine is contraindicated. However, the unpleasantness of awake partial curarization may limit its acceptance.