MORPHINE PATIENT-CONTROLLED ANALGESIA IS SUPERIOR TO MEPERIDINE PATIENT-CONTROLLED ANALGESIA FOR POSTOPERATIVE PAIN

The choice between morphine and meperidine for postoperative pain is u sually based on the preference of the prescriber, as few objective com parative data are available. This blind, randomized study compared the efficacy and side effects of morphine and meperidine administered by patient-controlled analgesia (PCA) for postoperative pain. One hundred two consenting patients scheduled for major abdominal surgery were ra ndomly assigned to receive PCA with morphine (0.75, 1.0, or 1.5 mg bol us dose size) or meperidine (9, 12, or 18 mg) for pain control. Postop erative assessments included pain at rest and on sitting, nausea, unus ual dreams, the Multiple Affect Adjective Check List (a measure of moo d), and the trailmaking tests A and B (measures of ability to concentr ate). Pain on sitting (P = 0.037) but not pain at rest (P = 0.8) was s ignificantly less in patients receiving morphine. Meperidine use was a ssociated with poorer performance in the trailmaking tests and a great er incidence of dryness of the mouth. Severity of nausea, mood, and in cidence of unusual dreams did not differ significantly between drugs. We conclude that meperidine should be reserved for those patients in w hom morphine is judged inappropriate.