Patient-controlled analgesia.

Patient-controlled analgesia is a relatively new and investigational technique that permits patients to treat pain by directly activating doses of intravenous narcotics. The technique was developed in response to the undertreatment of pain in hospitalized patients. Continuous narcotic infusion and intraspinal narcotic administrations also have the potential to provide continuous, uninterrupted analgesia, but do not allow simple dose attentuation to avoid overdosage. Patient-controlled analgesia is used to treat postoperative and labor pain and pain associated with terminal illness; it delivers analgesic more effectively with fewer side effects than conventional parenteral narcotic therapies. The technique is also an ideal investigative instrument for studying equianalgesic states. Several foreign-made devices are now being used under investigational sanctions in this country, and it is anticipated that several American manufacturers will be seeking regulatory approval to market the devices.