Early extubation after high-dose fentanyl anaesthesia for aortocoronary bypass surgery: reversal of respiratory depression with low-dose nalbuphine

• Published in: Canadian Anaesthetists' Society journal Vol. 32; no. 6; pp. 597 - 606
• Main Authors: RAMSAY, J. G, HIGGS, B. D, WYNANDS, J. E, ROBBINS, R, TOWNSEND, G. E
• Format: Journal Article
• Language: English
• Published: Toronto, ON Canadian Anaesthetists' Society 01.11.1985
• Subjects: Anesthesia; Anesthesia depending on type of surgery; Anesthesia, General - methods; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Bicarbonates - blood; Biological and medical sciences; Carbon Dioxide - blood; Coronary Artery Bypass; Fentanyl - antagonists & inhibitors; Fentanyl - therapeutic use; Humans; Kinetics; Medical sciences; Morphinans - therapeutic use; Nalbuphine - therapeutic use; Oxygen - blood; Partial Pressure; Respiration - drug effects; Thoracic and cardiovascular surgery. Cardiopulmonary bypass; Time Factors; Human; Intravenous administration; Respiratory failure; Surgery; Low dose; Coronary artery; General anesthesia; High dose; Extubation
• ISSN: 0008-2856; 1496-8975
• DOI: 10.1007/BF03011405

To investigate the possibility of selective reversal of narcotic-induced respiratory depression following fentanyl anaesthesia, we studied 20 patients after aortocoronary bypass surgery. All patients were anaesthetized with fentanyl, 40 micrograms . kg-1 and oxygen, with isoflurane as indicated. In a random double blind fashion either incremental doses of nalbuphine, or normal saline were administered approximately four hours after cardiopulmonary bypass. Respiratory depression was evaluated using blood gas and end tidal CO2 (PETCO2) measurement, and in addition, a ventilatory response to CO2 was obtained preoperatively and at selected intervals postoperatively. Despite randomization, patients with more respiratory depression were assigned to nalbuphine. There appeared to be a reversal of respiratory depression with nalbuphine, indicated by a fall in the resting PETCO2 value. This apparent reversal of respiratory depression was associated with a significant increase in pain, requiring treatment in three patients. We conclude that low-dose nalbuphine is not an acceptable method of antagonism of respiratory depression in this group of patients. Many patients who did not receive nalbuphine were able to breathe adequately at an earlier stage than was previously suspected. Close monitoring of the respiratory system may permit earlier extubation without the requirement of a narcotic antagonist after this dose of fentanyl.