Adolescent Adult Aged Aged, 80 and over Air Ambulances--statistics & numerical data Analgesia--methods Analgesics, Opioid--therapeutic use Child Child, Preschool Documentation--statistics & numerical data Dose-Response Relationship, Drug Female Fentanyl--therapeutic use Humans Hypotension--chemically induced Infant Intubation, Intratracheal--statistics & numerical data Male Massachusetts Middle Aged Outcome and Process Assessment, Health Care Pain--diagnosis Pain Measurement--statistics & numerical data Respiratory Insufficiency--chemically induced Wounds and Injuries--complications