Forty-seven patients who were treated for thoracoabdominal or thoracic
aneurysms over a 5 1/2-year period were analyzed for
neurologic deficit risk. Patients were divided into two groups for analysis. Twenty-four patients, who were treated from January 1984 to December 1986, did not undergo spinal fluid drainage or
naloxone administration (group A). Twenty-three patients, who were treated from January 1987 to August 1989, had spinal fluid drainage (group B); 12 patients in this group also received
naloxone as an
intravenous drip at 1 microgram/kg/hr for 48 hours after surgery. Permanent
neurologic deficits occurred in seven (29%) group A patients but in only one (4%) group B patient, who did not receive
naloxone (p less than 0.03). The first two group B patients to receive
naloxone showed complete reversal of
neurologic deficits on waking from
anesthesia. This significant reduction in
neurologic deficit was associated with an increased 1-year survival rate (72% in group
A, 91% in group B). We conclude that the use of
naloxone and spinal fluid drainage reduces the incidence of
neurologic deficit that is associated with repair of thoracoabdominal and
thoracic aortic aneurysms. This reduction in
neurologic deficit is associated with improved survival in the long term. The observed reversal of postoperative
neurologic deficits with
naloxone implicates
opiates as a major factor in the pathophysiology of
spinal cord ischemia.