To the Editor:

In the recent article by Yoo et al. [1] assessing the effect of dexmedetomidine pretreatment on the median effective bolus dose of propofol for facilitating laryngeal mask airway insertion, dexmedetomidine 1 µg/kg was infused over 10 min, followed by propofol 2.5 mg/kg administration and the laryngeal mask airway was inserted. The main disadvantage of using dexmedetomidine as a drug of anesthesia induction is slow onset. Because intravenous administration of dexmedetomidine has an onset of action after approximately 15 min in healthy adults, it is recommended that a single dose dexmedetomidine should be given 15 min before anesthesia induction [2]. Moreover, in the methods, there was no mention of time to start the laryngeal mask airway insertion after completion of propofol administration. After intravenous injection of propofol, the time to reach peak effect is about 100–120 s [3].

It must be emphasized that when anesthesia induction is performed with dexmedetomidine and propofol, clinicians should use the two drugs in such a way that their peak effects appear at the same time, acquiring most effective sedation and analgesia for subsequent airway procedure. We believe that a different median effective bolus dose of propofol for facilitating the laryngeal mask airway insertion would have been obtained if such an optimal drug administration planning was used in this study.