Etiology	Risk Factors
Intraoperative Characteristics	Patient Characteristics
Laryngospasm	Young, Healthy, Athletic ^b
Endotracheal Tube Biting	Obstructive Sleep Apnea
Airway Trauma	Surgical Procedures^c
Upper Airway Collapse
Bronchial Obstruction
Foreign Body Aspiration
Post-operative Residual Curarization^a