Laryngeal mask airway placement in children prior to an intravenous line utilizing heart rate as an indicator of anesthetic depth.

Introduction: The usual practice in pediatric anesthesia cases requiring a laryngeal mask airway is to place an intravenous line (IV) prior to laryngeal mask airway placement. A different approach that has several clinical advantages is to place the laryngeal mask airway prior to the IV. We describe our experience with this technique, using heart rate as an indicator of adequate anesthetic depth. In addition, we analyzed heart rate data in children undergoing sevoflurane inductions, looking for age-related differences.

Methods: Following a sevoflurane induction, heart rates were recorded every 12 s for 3 min in 127 ASA I-II children under age 7. Laryngeal mask airway placement occurred when the heart rate dropped at least 10% from its maximum level or at 3 min. Ease of laryngeal mask airway placement was graded using a scale from 0 to 3. Endtidal sevoflurane concentration, occurrence of laryngospasm and blood pressure at laryngeal mask airway placement were also recorded.

Results: The laryngeal mask airway was successfully placed on the first attempt in all 127 children. Easy placement was noted in 98.4%. The youngest children's heart rates peaked earlier than the oldest (P < 0.001), while time to laryngeal mask airway placement increased with increasing age (P < 0.0001).

Conclusions: Laryngeal mask airway placement before an IV is a safe alternative to the usual mask-IV-laryngeal mask airway sequence. Our data compare favorably to other studies where ease of laryngeal mask airway placement was reported. This technique has several advantages including securing the airway first for an anticipated difficult IV placement. Heart rate changes during a sevoflurane induction appear to be age-dependent.