Objectives: We aimed to investigate the reliability of the hypothesis that whether sevoflurane-remifentanil could offer equivalent intubation conditions with propofol-remifentanil in the absence of muscle relaxants.
Materials and methods: Total of 80 patients of ASA grades I and II scheduled for elective surgery were randomly allocated into two groups. Patients in group I received an infusion of remifentanil 1 mcg/kg/min and inhalation of sevoflurane 8% until the Bispectral index (BIS) being less than 60. Patients in group II received a co-infusion of remifentanil and propofol 1 mg/kg/h until BIS is <60. Intubation was attempted when BIS is <60. Intubation conditions were assessed as optimal, good, marginal, and poor using vocal cord opening, jaw relaxation and patient's movements. The heart rate and mean arterial blood pressure (ABP) were recorded before and during the induction, and thereafter, 1, 2 and 5 minutes following intubation. The time for BIS to be <60 was recorded.
Results: Optimal intubation conditions were achieved more often in group II than in group I (90% versus 45%, p=0.002). The ratio of patients showing optimal or good intubating conditions was 80% in group I and 100% in group II (p=0.035). Time required for BIS was shorter in group II than in group I (47.1±27.2 sec vs. 111.9±60.6 sec, p<0.001). In both groups, there was a decrease in heart rate and mean ABP compared to baseline.
Conclusion: Under BIS monitorization, propofol-remifentanil combination offered better intubation conditions and shorter anesthesia induction period compared with sevoflurane-remifentanil.