Respiratory and cardiovascular effects of fentanyl during propofol-induced sedation under spinal anesthesia

Abstract

Purpose: To determine whether fentanyl augments respiratory and cardiovascular problems during propofol-induced sedation, we investigated the effects of propofol and fentanyl on respiratory and hemodynamic profiles in 30 female patients under spinal anesthesia, administering oxygen via face mask.

Methods: After spinal anesthesia, 20 patients were sedated with propofol (0.5 mg·kg^-1 bolus, 3 mg·kg^-1·h^-1), followed by administration of either 2 μg·kg^-1 fentanyl in group PF or normal saline in group P, whereas another 10 patients (group F) received 2 μg·kg^-1 fentanyl without propofol. We measured heart rate, mean arterial pressure, end-tidal carbon dioxide tension, and respiratory rate before and after treatment. We also evaluated apnea, arterial oxygen desaturation, and airway obstruction.

Results: Mean arterial pressure was significantly lower in group P and PF than in group F. However, there were comparable changes in heart rate in the three groups. The combination of fentanyl and propofol decreased respiratory rate and increased end-tidal carbon dioxide tension more than fentanyl or propofol alone. Although apnea occurred in groups F and PF, arterial oxygen desaturation did not occur in any of the groups.

Conclusion: The combination of fentanyl and propofol augmented the risks of respiratory depression and apnea compared with the use of fentanyl or propofol alone.

Keywords: Airway obstruction; Apnea; Fentanyl; Propofol; Sedation.