[Spinal cord protection and opioids].
Opioids, when administered in large doses, were reported to produce brain damage primarily in limbic system and association areas in animals. We recently found the result that intrathecal (IT) morphine after a short interval of aortic occlusion in the rodent model induced transient spastic paraparesis via opioid receptor-coupled effects in the spinal cord. Histopathological analysis revealed the possibility that IT morphine could induce degeneration of spinal ventral neurons even after a short lasting of spinal cord ischaemia in rats, and this degeneration was associated with the activation of spinal N-methyl-D-aspartate receptors by elevation of glutamate release in cerebrospinal fluid after IT morphine. Therefore, we would like to emphasize that all anesthesiologists should be aware of the possibility of morphine-induced paraplegia after thoracic aortic surgery and that we should carefully select appropriate analgesic agents from the several available opioids for these patients.
Kakinohana
Manabu
M
Department of Anesthesiology, Faculty of Medicine, University of the Ryukyus, Okinawa.
D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000009:adverse effects*; D000818:Animals; D000870:Anterior Horn Cells / Q000187:drug effects / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D005283:Fentanyl / Q000008:administration & dosage / Q000009:adverse effects; D018698:Glutamic Acid / Q000134:cerebrospinal fluid; D006801:Humans; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects; D009270:Naloxone / Q000008:administration & dosage; D009410:Nerve Degeneration / Q000139:chemically induced; D020336:Paraparesis, Spastic / Q000139:chemically induced; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D020760:Spinal Cord Ischemia / Q000139:chemically induced* / Q000517:prevention & control*; D019616:Thoracic Surgical Procedures
D000701:Analgesics, Opioid; D016194:Receptors, N-Methyl-D-Aspartate; D009270:Naloxone; D018698:Glutamic Acid; D009020:Morphine; D005283:Fentanyl