Advantages of Buprenorphine in Comparison to Morphine in Postoperative Pain Control.

Pre-emptive analgesia has been used widely and effectively for post operative pain relief. In this study Bupernorphine, a partial agonist of opioids has been compared to Morphine as preemptive analgesic with the aim to achieve better pain control and less post operative complications.Methods and Material: In this randomized double blind clinical trial, 60 patients were assigned in two equal groups of study (each group=30). Bupernorphine group received 4mcg/kg IV of the drug and morphine group received 0.1mg/kgIV of the drug, 10 minutes before induction of anesthesia. The average time of the first demand for post operative analgesic, the frequencies of demands and the total amount of administered analgesics were recorded. The incidence of post operative complications such as respiratory depression and postoperative nausea and vomiting (PONV) were recorded. The average time of the first demand for analgesic in Bupernorphine group (410±20minutes) was significantly longer than morphine group (240±25minutes), p<0.0001. The number of patients demanded analgesic were lower in Bupernorphine group (46.7%) than morphine group (90%), p<0.0001. The average increase in arterial paco2 was higher in Morphine group. No significant differences were noted between two groups in the incidence of post operative shivering and Nausea and vomiting. Intravenous Bupernorphine before induction of anesthesia was more effective and had fewer side effects than morphine in post operative pain management.