Morphine sparing with droperidol in patient-controlled analgesia.

STUDY OBJECTIVE

To determine if droperidol has a morphine-sparing effect when coadministered with morphine via patient-controlled analgesia (PCA) for postoperative pain management.

DESIGN

A randomized, double-blind clinical study.

SETTING

Department of Anesthesiology, Kaohsiung Veterans General Hospital, Taiwan.

PATIENTS

One hundred seventy-nine American Society of Anesthesiologists physical status 1 and 2 female patients undergoing abdominal hysterectomy.

INTERVENTIONS

At the end of surgery, patients in the droperidol group received PCA, with the device programmed to deliver a bolus dose of 1 mg morphine and 50 mug droperidol on demand. Patients in the control group received 1 mg morphine on demand. For both groups, PCA lockout was 5 minutes between boluses, with a 4-hour morphine limit of 30 mg.

MEASUREMENTS AND MAIN RESULTS

Pain intensity at rest or on movement and relative sedation score were evaluated and recorded at 6, 12, 24, 48, and 72 hours after surgery. Related side effects were also evaluated and recorded on postoperative days 1, 2, and 3. Morphine use was significantly lower for the droperidol group than the control group during the postoperative 72-hour period (33.9 +/- 9.8 and 54.9 +/- 12.1 mg, respectively), with significantly decreased pain intensity levels for the former relative to the latter at 48 hours (pain intensity on movement: 3.9 +/- 1.2 vs 4.3 +/- 0.9, respectively; P = .049) and 72 hours (pain intensity on movement: 3.0 +/- 1.1 vs 3.6 +/- 0.5, respectively; P = .003; pain intensity at rest: 1.3 +/- 1.0 vs 1.6 +/- 0.7, respectively; P = .033) subsequent to surgery. Control subjects demonstrated a greater frequency of postoperative nausea and vomiting than did their droperidol counterparts on postoperative day 1.

CONCLUSION

Coadministration of 50 mug droperidol and 1 mg morphine on demand via PCA provides a morphine-sparing effect and reduces the frequency of postoperative nausea and vomiting.