Effects of Morphine, Fentanyl and Ketorolac Tromethamine, Droperidol Intravenous Infusion for Postoperative Pain Control

Lee, Hyang Joo; Lee, Kang Chang; Kim, Tai Yo

Abstract

Continuous intravenous infusions of opioids can provide better pain relief than intermittent injection but may be associated with increased incidence of undesirable side effects including respiratory depression, nausea, vomiting and urinary retention. Ketorolac tromethamine is a new, nonsteroidal anti-inflammatory agent. It has significant analgesic properties without respiratory and cardiovascular depression. Mixing of opioids and ketorolac may lessen these complications without reducing analgesic effect. In six groups, we assessed the effect of postoperative pain control using morphine or fentanyl, ketorolac and droperidol, Each group consists of 100 patients. Patients in group 1, group 2, and group 3 received 2 mg of morphine via intravenous injection following the induction of anesthesia. Patients in group 1 were then continuously infused with additional 48 mg of morphine, patients in group 2 received additional 18 mg of morphine plus 120 mg of ketorolac, and patients in the group 3 were treated with the same protocol as group 2 but 2.5 mg of droperidol was added. For patients in group 4, group 5, and group 6 initially received 20 ug of fentanyl after induction of anesthesia. The rest of dose were treated with similar protocols as group I, group 2, group 3, respectively. In group 4, group 5, and group 6, morphine was substituted to 500 ug, 200 ug, and 200 ug of fentanyl, respectively. In all patients, initial dose of drug was given by bolus of intravenous injection and the rest of dose was delivered via intravenous using a Baxter Two Day Infusor or a Paragon 100. Pain scores and side effects were recorded every twelve hours for three days. No significant difference was found between the groups although pain control effect was excellent in all groups. Untoward effects were least in morphine or fentanyl-ketorolac-droperidol(group 3, group 6). It could be concluded that mixing of opioids, ketorolac and dtoperidol would be better than opioids alone.