Purpose: In this prospective, randomized, controlled trial, we investigated the reliability of laryngeal mask airway (LMA) insertion with inhaled desflurane.
Methods: Eighty patients undergoing elective surgery were randomized into two groups to receive either 2.5 mg x kg(-1) propofol (n = 40) or tidal breath desflurane (n = 40) induction followed by LMA insertion. All patients received fentanyl 1 microg x kg(-1) 2 min before induction. Inhalation of desflurane was started at 3% and increased by 3% every 3-5 breaths up to settings of 12%.
Results: Insertion of the LMA was faster in the propofol group (131.8 s versus 228.6 s, P < 0.01). The number of patients in whom the jaw opening was described as good (95% versus 72.5%, P = 0.27, for the desflurane and propofol groups, respectively) and the ease of LMA insertion described as good (87.5% versus 72.5%, P = 0.6) were comparable. The LMA was inserted in a single attempt in the majority of patients in both groups (80% versus 77.5%, P = 0.90). There were more complications at insertion in the propofol group than in the desflurane group (2.5% versus 19.5%, P < 0.01), especially for apnea (7.5% versus 70%, P < 0.01) and excitatory movements (2.5% versus 25%, P < 0.01). There were significant decreases in the mean arterial pressure in the propofol group compared to baseline data over the first 5 min of induction. Mean arterial pressure, heart rate, and S(p)(O2) remained stable during the same period in the desflurane group.
Conclusion: We demonstrated that inhaled desflurane when used with caution in a controlled manner provided acceptable conditions for LMA insertion.