Opening the upper airway--airway maneuvers in pediatric anesthesia.

Maintenance of a patent airway is the most important aspect of the safe administration of anesthesia in children. However, in spontaneously breathing, anesthetized children, upper airway obstruction is a frequent problem (1) and failure to maintain a patent airway can rapidly result in hypoxemia, bradycardia or even cardiac arrest. Upper airway narrowing is most likely to appear in pharyngeal structures (2–4). Since the entire airway is composed of soft tissue and is kept patent during inspiration by the dilating action of the pharyngeal airway muscles, any drug that leads to a reduction of muscle activity can reduce airway patency and thus increase upper airway resistance (5). Children are particularly susceptible to upper airway obstruction because of the smaller dimensions of their airways and the high incidence of tonsillar and/or adenoidal hypertrophy which causes increased resistance to flow (6). During anesthesia and basic life support, positioning of body, head and neck as well as airway maneuvers such as jaw thrust and chin lift are commonly used to improve the patency of an obstructed or partially obstructed upper airway (7, 8). The importance of these maneuvers has been known for a long time; Jacob Heiberg wrote in 1874 that during chloroform anesthesia, noisy, obstructed breathing, particularly during inspiration, can be prevented by pulling the jaw forward (9), while other authors have even earlier advocated opening obstructed airways by pulling the tongue forward (10–12). This review focuses on the mechanisms and efficacy of different, simple methods to open and maintain a patent airway in spontaneously breathing children undergoing anesthesia, which include body, head and neck positioning and airway maneuvers such as mouth opening, chin lift, jaw thrust or the use of continuous positive airway pressure (CPAP).