The optimal effect site concentration of remifentanil in combination with intravenous midazolam and topical lidocaine for awake fibreoptic nasotracheal intubation in patients undergoing cervical spine surgery Full Text
Minerva Anestesiologica, 04/27/2012
Song JW et al. – The estimated EC95 of remifentanil effect site concentration (Ce) for smooth nasotracheal fibreoptic intubation with conscious sedation was 3.38ng.mL-1 when used in combination with midazolam and topical lidocaine. Remifentanil target–controlled infusion (TCI) may provide a tolerable experience of awake fibreoptic intubation despite the high incidence of recall.Methods
- Nineteen ASA I-II patients were enrolled. Patients were premedicated with midazolam (<70kg 1.5mg; >70kg 2.0mg) intravenously.
- The EC50 and EC95 of remifentanil Ce for smooth intubation were determined using Dixon’s up-and-down method and isotonic regression.
- Smooth intubation was considered to have failed when patients exhibited sustained and repetitive coughing with head lift during the procedure.
- Intubation time, number of attempts, adverse events, and hemodynamic variables were also recorded.
- Patients were asked to recall the procedure and grade satisfaction at postoperative 24h.
- The EC50 of remifentanil Ce for smooth intubation was 2.33±0.38ng.mL-1 as calculated by Dixon’s method.
- The estimated EC95 of remifentanil Ce was 3.38 (95% confidence interval 2.90-3.46)ng.mL-1.
- Median intubation time (min) was longer in failed smooth intubation than in smooth intubation (8.0 vs. 6.1, P=0.048).
- Eleven patients (58%) recalled the procedure and 16 patients (84%) rated their satisfaction score as good or excellent.