Acetaminophen/therapeutic use; Analgesics, Non-Narcotic/therapeutic use; Gastrointestinal Contents/drug effects; Premedication; Stomach/drug effects; Absorption; Acetaminophen/administration & dosage; Acetaminophen/pharmacokinetics; Adenoidectomy; Administration, Oral; Administration, Rectal; Ambulatory Surgical Procedures; Analgesics, Non-Narcotic/administration & dosage; Analgesics, Non-Narcotic/pharmacokinetics; Child; Female; Gastric Mucosa/metabolism; Humans; Hydrogen-Ion Concentration; Intestinal Absorption; Intraoperative Care; Intubation, Gastrointestinal; Male; Stomach/physiology; Suction; Suppositories; Tonsillectomy