Coadministration of intravenous remifentanil and morphine for post-thoracotomy pain: comparison with intravenous morphine alone

Abstract

Objectives: In this double-blind, randomized study, the authors compared the effects of a patient-controlled remifentanil and morphine combination with morphine alone on post-thoracotomy pain, analgesic consumption, and side effects.

Design: A prospective, randomized, double-blind clinical study.

Setting: University hospital.

Participants: Volunteer patients at a university hospital undergoing elective thoracotomy surgery.

Interventions: Patients were allocated randomly into 2 groups to receive patient-controlled analgesia: the morphine (M) group or the morphine plus remifentanil (MR) group. Pain, discomfort, sedation scores, cumulative patient-controlled morphine consumption, rescue analgesic (meperidine) requirement and side effects were recorded for 24 hours.

Measurements and main results: Sixty patients were allocated randomly to receive intravenous patient-controlled analgesia with morphine alone (M) or morphine plus remifentanil (MR) in a double-blind manner. Patients were allowed to use bolus doses of morphine (0.02 mg/kg) or the same dose of a morphine plus remifentanil (0.2 µg/kg) mixture every 10 minutes without a background infusion. VAS scores were lower in the MR group than in the M group at 30 minutes (p = 0.04), 1 hour (p = 0.03), and 2 hours (p = 0.04). Mean cumulative doses of morphine were not significantly different at 27.8±15 mg for the M group and 21.9±10.5 mg for the MR group. Significantly more patients needed meperidine in the M group (p = 0.039); these also experienced more nausea (p = 0.01).

Conclusions: Coadministration of PCA remifentanil with morphine for the treatment of post-thoracotomy pain did not reduce morphine consumption but provided superior analgesia, less use of rescue analgesics, and fewer side effects compared to morphine alone.

Keywords: morphine; patient-controlled analgesia; post-thoracotomy pain; remifentanil.