The effect of fentanyl anesthesia and intrathecal naloxone on neurologic outcome following spinal cord injury in the rat.
Whereas opiate receptor agonists have resulted in spinal cord damage; opiate receptor antagonists have demonstrated protection against spinal cord injury. Because opioids are used in clinical anesthesia, the effect of an opiate antagonist was evaluated on neurologic outcome in a rat model of spinal cord injury occurring during opioid anesthesia. One day prior to spinal cord injury, a catheter was inserted into the spinal subarachnoid space with the tip at T8. On the day of spinal cord injury a balloon tipped catheter was inserted in the epidural space with the tip at the thoracolumbar junction. Spinal cord injury was produced by balloon inflation during one of the following states: 1) group 1 (A/S), injury was produced in awake rats and saline was administered in the subarachnoid space immediately following injury; 2) group 2 (F/S), injury was produced during a fentanyl/nitrous oxide (N2O) anesthetic, and subarachnoid saline administered; and 3) group 3 (F/Nx), injury was produced during a fentanyl/N2O anesthetic, and subarachnoid naloxone (1 mg/kg) was administered immediately following injury. Dose-response curves describing the relationship between the duration of balloon inflation and the percentage of animals with a persistent neurologic deficit were constructed and compared for differences by use of a group t test. The duration of balloon inflation required to produce a neurologic deficit was greater in both the F/S and F/Nx groups than in the A/S group (P less than 0.05). There was no difference between the F/S and F/Nx groups. In summary, in rats receiving a fentanyl/N2O anesthetic, neurologic outcome was improved compared with the awake state.(ABSTRACT TRUNCATED AT 250 WORDS)
Cole
D J
DJ
Department of Anesthesiology, Loma Linda University, California 92354.
Drummond
J C
JC
Shapiro
H M
HM
Hertzog
R E
RE
Brauer
F S
FS
D000762:Anesthesia Recovery Period; D000818:Animals; D002404:Catheterization / Q000379:methods; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005283:Fentanyl / Q000009:adverse effects; D007278:Injections, Spinal; D007530:Isoflurane; D008297:Male; D009270:Naloxone / Q000008:administration & dosage*; D009420:Nervous System / Q000187:drug effects* / Q000503:physiopathology; D009609:Nitrous Oxide; D051381:Rats; D011919:Rats, Inbred Strains; D013119:Spinal Cord Injuries / Q000209:etiology / Q000503:physiopathology*; D013346:Subarachnoid Space; D013997:Time Factors
D009270:Naloxone; D007530:Isoflurane; D009609:Nitrous Oxide; D005283:Fentanyl