[Analgesic and respiratory effects of nalbuphine during the immediate postoperative period in thoracotomy].

As most patients undergoing pulmonary surgery by postero-lateral thoracotomy have decreased preoperative pulmonary function, efficient postoperative analgesia is mandatory. Nalbuphine, a new agonist-antagonist opioid analgesic, and nefopam were compared in a double blind trial involving 60 patients. Intravenous injections of 0.3 mg.kg-1 of either drug were started when the patient evaluated his pain as being above 60 mm on a visual scale graduated from 0 to 100 mm. Repeated injections were carried out at the same dose, at the patient's request, after a minimal interval of 3 h for nalbuphine, and 6 h for nefopam. Analgesia was assessed by the visual scale, and by the patient's verbal appraisal. The respiratory and cardiovascular repercussions were evaluated clinically, and by monitoring breathing rate, blood gases, systolic and diastolic blood pressures, heart rate, and consciousness. Nalbuphine provided a convenient analgesia to all patients whereas analgesia with nefopam was insufficient in 15 out of 30 patients. No significant respiratory depression with either drug occurred. Nefopam led to a 30% increase in heart rate for one hour (p less than 0.01). Whereas patients given nalbuphine were more drowsy, although easily aroused, (p less than 0.001), nefopam was responsible for adverse effects (sweating, nausea, tachycardia with pallor, vertigo, malaise) requiring the exclusion of 7 patients from the study. Nalbuphine, although not ideal, would therefore seem to be a better analgesic than nefopam in thoracotomy patients.