Effect-site concentration of remifentanil to blunt the hemodynamic changes during rapid sequence intubation

ABSTRACT

BACKGROUND: This study was undertaken to evaluate the effect-site concentration of remifentanil to blunt the hemodynamic changes during rapid sequence intubation. METHODS: Eighty patients were enrolled and divided into four groups being assigned with different effect-site concentrations (Ce)of remifentanil of 0, 2, 3, or 4 ng/ml. Patients arrived at the operating room without premedication and their baseline vital signs were recorded. With preoxygenation of 100% O2, remifentanil was infused by target controlled infusion according to patient group. After achievement of a stable level of Ce, propofol 2 mg/kg and rocuronium 1.2 mg/kg were injected and the trachea was intubated one minute later. Hemodynamic changes were recorded at 1, 2, and 3 min after remifentanil infusion, immediately before and after endotracheal intubation, and 1 and 2 min after endotracheal intubation. RESULTS: The 50% effective Ce of remifentanil was 1.4 ng/ml (95% confidence interval, CI 0.9-1.8) to blunt the increase of mean blood pressure and was 2.4 ng/ml (95% CI 1.6-3.1) to blunt the increase of heart rate. The 50% Ce for the decrease of mean blood pressure was 2.8 ng/ml (95% CI 2.2-3.4). CONCLUSIONS: During the rapid sequence intubation, the 50% effective effect site concentration of remifentanil to prevent hemodynamic changes is between 2.4 and 2.8 ng/ml.