Tracheal intubation conditions and cardiovascular effects after modified rapid-sequence induction with sevoflurane-rapacuronium versus propofol-rapacuronium

To compare intubation conditions and hemodynamic effects resulting from rapid-sequence induction of anesthesia with sevoflurane-rapacuronium and propofol-rapacuronium.

Randomized, blinded study.

Operating suites of a large university-affiliated medical center.

40 ASA physical status I and II adult patients without airway abnormalities who were scheduled for elective surgery requiring endotracheal intubation.

Patients were randomly allocated to receive either sevoflurane inhalational induction (Group 1) or propofol (2 mg/kg) intravenous induction (Group 2). Group 1 patients were coached on how to perform vital capacity breathing and the anesthesia machine was primed with sevoflurane 8%, N2O:O2 3.5:1.5 L/min. In both groups, when loss of consciousness was established, rapacuronium 1.5 mg/kg was administered. After 50 seconds, an anesthesiologist blinded to the study entered the room and attempted laryngoscopy and intubation.

Intubation conditions were graded as excellent, good, poor, or impossible according to Good Clinical Research Practice (GCRP) criteria. Arterial blood pressure and heart rate changes accompanying both induction techniques were also monitored and recorded.

All patients were successfully intubated within 60 seconds. Clinically acceptable intubating conditions (excellent or good scores) were obtained in 19 of 20 Group 1 patients and in 19 of 20 Group 2 patients. Moderate tachycardia was encountered in both groups and mild systolic hypotension in the Group 2 patients. There were no complications.

Modified rapid-sequence inhalational induction using sevoflurane and rapacuronium produced clinically acceptable intubation conditions within 60 seconds of muscle relaxant administration. The intubation conditions were similar to those produced after intravenous propofol and rapacuronium.