Monitored anesthesia care for great saphenous vein stripping surgery with target controlled infusion of propofol and remifentanil: a prospective study

Effects of age on effect-site concentration of remifentanil for suppressing anesthetic emergence cough in male patients undergoing laparoscopic cholecystectomy

Background

Remifentanil infusion during emergence lowers cough. Effect-site concentration (Ce) of remifentanil using target-controlled infusion (TCI) has been evaluated in previous studies. Recent studies revealed the existence of sex-related differences in remifentanil Ce in young and elderly patients. Thus, there was the need to re-evaluate the effect of age in single sex. We investigated the remifentanil Ce for suppressing emergence cough in young and elderly male patients and evaluated the age-related differences.

Patients and methods

In total, 25 young (ages between 20 and 50 years) and 24 elderly (ages between 65 and 75 years) male patients undergoing laparoscopic cholecystectomy were enrolled. Anesthesia was implemented with remifentanil using TCI and sevoflurane. The remifentanil Ce for suppressing emergence cough was estimated for each group using Dixon’s up-and-down method and isotonic regression method with a bootstrapping approach.

Results

The remifentanil Ce for suppressing emergence cough in 50% (EC₅₀) and 95% (EC₉₅) of the patients was comparable between the young and elderly patients. Isotonic regression demonstrated that the EC₅₀ (83% confidence interval [CI]) of remifentanil was 2.56 (2.39−2.75) ng/mL in the young patients and 2.15 (1.92−2.5) ng/mL in the elderly patients. The EC₉₅ (95% CI) of remifentanil was 3.33 (2.94−3.46) ng/mL in the young patients and 3.41 (3.18−3.48) ng/mL in the elderly patients. Dixon’s up-and-down method also demonstrated that the EC₅₀ was comparable between the two groups (2.69±0.32 ng/mL vs 2.39±0.38 ng/mL, P=0.132).

Conclusion

The remifentanil Ce for suppressing emergence cough following extubation during general anesthesia was comparable between young and elderly male patients. It indicates that age-related differences in remifentanil requirement for suppressing emergence cough did not exist in male sex.

The efficacy of dexmedetomidine-remifentanil versus dexmedetomidine-propofol in children undergoing flexible bronchoscopy: A retrospective trial

Flexible bronchoscopy has been more and more used for diagnosis and management diseases of respiratory system in pediatrics. Previous studies have reported that remifentanil (RF) and propofol are safe and effective for flexible bronchoscopy in adults, however, there have no trials evaluate the efficacy of DEX-RF versus dexmedetomidine-propofol in children undergoing flexible bronchoscopy.We divided 123 children undergoing flexible bronchoscopy with DEX-RF or dexmedetomidine-propofol into 2 groups: Group DR (n = 63, DEX infusion at 1.0 μg kg for 10 minutes, then adjusted to 0.5-0.7 μg kg h; RF infusion at 1.0 μg kg for 5 minutes, then adjusted to 0.05-0.2 μg kg min), Group DP (n = 60, DEX infusion at 1.0 μg kg for 10 minutes, then adjusted to 0.5-0.7 μg kg h; propofol infusion at 10 μg kg for 5 minutes, then adjusted to 0.05-0.1 μg kg min). Ramsay sedation scale of the 2 groups was maintained at 3. Anesthesia onset time; total number of intraoperative patient movements; hemodynamics; total cumulative dose of DEX; amount of and time to first-dose rescue midazolam and lidocaine; postoperative recovery time; adverse events; and bronchoscopist satisfaction score were recorded.Anesthesia onset time was significantly shorter in DP (8.22 ± 2.48 vs 12.25 ± 6.43 minutes, respectively, for DP, DR, P = 0.015). The perioperative hemodynamic profile was more stable in DR than DP group. More children moved during flexible bronchoscopy in DP group (P = 0.009). Total dose of rescue midazolam and lidocaine was significantly higher in DR than in DP (P < 0.001). Similarly, the time to first dose of rescue midazolam and lidocaine was significantly longer in DP than in DR (P < 0.001). Total cumulative dose of DEX was more in DR than DP group (P < 0.001). The time to recovery for discharge from the postanesthesia care unit (PACU) was significantly shorter in DP than in DR group (P < 0.001). The bronchoscopist-satisfaction scores were higher for DR than DP (P = 0.036). There were significant differences between the 2 groups in terms of the overall incidence of hypertension, tachycardia, and hypoxemia (P < 0.05).Although underwent longer recovery time and more incidence of rescue scheme, DEX-RF resulted in more stable hemodynamic profiles and bronchoscopist-satisfaction scores, lesser patient movements, and can hence be more effectively used in children undergoing flexible bronchoscopy than dexmedetomidine-propofol.