title: Systems modification in obstetric analgesia.
abstract: The need is identified of certain women in labour for a more potent analgesic than entonox. We describe a modification of the Entonox demand system incorporating an Oxford Miniature Vaporizer and there is a discussion directed towards its supervision.
mesh_terms: D000769:Anesthesia, Inhalation / Q000295:instrumentation*; D000773:Anesthesia, Obstetrical / Q000295:instrumentation*; D004338:Drug Combinations / Q000008:administration & dosage; D004867:Equipment Design; D005260:Female; D006801:Humans; D007743:Labor, Obstetric; D009609:Nitrous Oxide / Q000008:administration & dosage*; D010100:Oxygen / Q000008:administration & dosage*; D011247:Pregnancy; D012646:Self Administration; D014241:Trichloroethylene / Q000008:administration & dosage*; D014835:Volatilization
chemical_list: D004338:Drug Combinations; D014241:Trichloroethylene; C001147:Entonox; D009609:Nitrous Oxide; D010100:Oxygen