Intravenous patient controlled analgesia (IV-PCA) is a very popular and relatively safe technique due to its innate negative feedback mechanism. Morphine, the most commonly used analgesic, however, has its own drawbacks due to troublesome side effects. Narcotic agonist-antagonists are known to have ceiling effects not only to their analgesic potency, but also to their side effects. The authors studied the efficacy and incidence of side effects of Butorphanol IV-PCA for postoperative analgesia and compared these to morphine.

38 ASA class I or II patients, undergoing gynecological surgery were randomly assigned into two groups, respectively Butorphanol and Morphine and examined hemodynamic changes, overall pain relief, patients satisfaction and the frequency of side effects. After general anesthesia, each patient randomly received loading dose of butorphanol or morphine in the recovery room and discharged to the floor with the PCA module. Upon arrival, individual patient was evaluated at predetermined time interval for 24 hours.

The percentage of patient satisfaction was very high in both groups. The incidence of nausea was less in butorphanol group. The incidence of other side effects was statistically insignificant.

Butorphanol has less incidence of side effects and comparable level of analgesia when compared to morphine. We conclude that butorphanol may be considered as a part of routine IV-PCA regimen, in postoperative pain management.