Minimum alveolar concentration of sevoflurane with a rapid intravenous administration of dexmedetomidine for deep extubation in children.

BACKGROUND

Deep extubation has potential advantages in certain patients and surgeries. The end tidal concentration of sevoflurane, the most used inhalation anesthetic in pediatric anesthesia, is an important factor to determine whether smooth deep extubation can be achieved. Dexmedetomidine decreases the requirement of volatile anesthetics. This study was conducted to determine the 50% effective end-tidal concentration of sevoflurane (ED50) for deep tracheal extubation in combination with an intravenous injection of low dose dexmedetomidine.

METHODS

Thirty-six children undergoing adenotonsillectomy, with ASA physical status I-II and aged 3-10 years, were enrolled in the study. At the end of surgery, 0.5 µg/kg dexmedetomidine diluted in 10 ml saline was administered. The up and down sequential study design was employed to determine the effective dose of sevoflurane for smooth deep extubation, starting at 1.0% with subsequent 0.1% up and down in the next patient based on whether smooth extubation had been achieved or not. Smooth extubation was defined as no movement, coughing, bucking, breath holding or laryngospasm within 1 min after extubation.

RESULTS

ED50 (95% CI) of the end-tidal concentration of sevoflurane required for smooth deep extubation was 0.90% (0.79-1.02%). ED95 (95% CI) values of sevoflurane was 1.70% (1.58-1.81%). No respiratory and hemodynamic complications were observed.

CONCLUSION

The ED50 of sevoflurane for smooth deep extubation with a 0.5 µg/kg bolus of dexmedetomidine administered before extubation was 0.90% in pediatric patients undergoing adenotonsillectomy with perioperative hydromorphone (5 µg/kg).

TRIAL REGISTRATION

ChiCTR2300070329, registered on 10 April 2023.