title: Counting angels.
authors: Andrew M
authors: AM
authors: Mason
mesh_terms: D000367:Age Factors; D000402:Airway Obstruction / Q000628:therapy*; D002648:Child; D002675:Child, Preschool; D004630:Emergencies; D004632:Emergency Medical Services / Q000379:methods*; D004867:Equipment Design; D019983:Guideline Adherence; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007442:Intubation, Intratracheal / Q000295:instrumentation* / Q000379:methods; D017410:Practice Guidelines as Topic