A pilot study of pain, analgesia use, and pulmonary function after colectomy with or without a preoperative bolus of epidural morphine.

OBJECTIVE

To determine whether patients who received a preoperative bolus of epidural morphine plus postoperative parenteral analgesia had less pain and better pulmonary function over the first 2 days after a colectomy than patients who received postoperative parenteral analgesia alone.

DESIGN

Repeated measures, quasi-experimental, random assignment.

SETTING

Northeastern general hospital.

SUBJECTS

Thirteen patients were randomized to receive parenteral with (n = 6) or without (n = 7) epidural analgesia.

OUTCOME MEASURES

Indicators of pain (intensity of pain and pain-related distress, intensity of words used to describe pain, intramuscular-equivalent amount of morphine administered, duration from start of surgery to first request for analgesia) and pulmonary function (forced expiratory volume in one second FEV1], forced vital capacity [FVC], inspiratory capacity [IC], peripheral oxygen saturation [SaO2] values).

MEASUREMENT

Indicators of pain and pulmonary function were obtained the day before surgery, approximately 6 hours after surgery, and the first two mornings after surgery.

RESULTS

Six hours after surgery, patients in the epidural group had less pain (p = 0.0177) and related distress (p = 0.0303) and greater FVC (p = 0.0303) and FEV1 (p = 0.0025) than patients in the no-epidural group. On the first postoperative morning, patients in the epidural group had less distress related to pain (p = 0.0350) but similar respiratory rates and spirometry values. Inspiratory capacity was not statistically different but was always larger in the epidural group. Of patients who breathed room air, SaO2 was higher in the epidural group over the first two postoperative days (p = 0.0286 each occasion). Patients in the epidural group received their first on-demand analgesic an average of 30 hours after the start of surgery compared with 6 hours for patients in the no-epidural group (p = 0.0022). There were no significant differences in the total number of words used to describe the type of pain, and both groups described the pain with fewer words than expected on the first and second mornings after surgery.

CONCLUSIONS

Results should be confirmed through study of a larger sample with the hypothesis that pain relief, selected aspects of pulmonary function, and peripheral oxygenation may be superior for patients who receive a preoperative bolus of epidural analgesia for abdominal surgery.