Balanced analgesia with intravenous ketorolac and patient-controlled morphine following lower abdominal surgery

To investigate the efficacy, opioid-sparing effects and any reduction in adverse events of a continuous intravenous (i.v.) infusion of ketorolac following lower abdominal surgery.

Randomized, double-blind, placebo-controlled, parallel-group study.

Inpatient elective gynecologic surgical patients.

60 ASA physical status I or II patients aged 18 to 70 years scheduled for elective abdominal hysterectomy.

Following standardized preparation and anesthesia, continuous i.v. infusions of either ketorolac or placebo were administered for 24 hours postoperatively with a patients' standardized postoperative protocol. Supplementary analgesia was administered by an i.v. patient-controlled analgesia (PCA) system.

A significantly lower proportion of the patients in the ketorolac group (6%) rated their pain at 24 hours as moderate or severe compared with patients in the placebo group (34%) (p = 0.04). Mean 24-hour morphine consumption was significantly lower in the ketorolac group (43 mg; SEM 5 mg) compared with the placebo group (55 mg SEM 5 mg) (p = 0.02). There was no significant difference in the incidence of postoperative hypoxemia between the groups with respect to mean times per hour spent with oxygen saturation (SPO2) less than 85%, more than 85% but less than 90%, or more than 90% but less than 94%, mean hourly SPO2, or the incidence and duration of severe hypoxemic episodes. Nausea and vomiting were the only significant adverse events, and they occurred in 30% of patients in both groups.

Intravenous infusion of ketorolac combined with morphine delivered via a PCA device would appear to be a valuable method of providing balanced analgesia following lower abdominal surgery.