This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Mutch, W. A. Articles by Thomson, I. R. Search for Related Content PubMed PubMed Citation Articles by Mutch, W. A. Articles by Thomson, I. R.

Stroke, Vol 24, 1554-1559, Copyright © 1993 by American Heart Association

ARTICLES

Paraplegia following thoracic aortic cross-clamping in dogs. No difference in neurological outcome with a barbiturate versus isoflurane

WA Mutch, MR Graham, WC Halliday, JM Teskey and IR Thomson
Department of Anesthesia, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.

BACKGROUND AND PURPOSE: We compared the incidence and severity of paraplegia following thoracic aortic cross-clamping in dogs for two anesthetic regimens. Animals were randomly assigned to receive methohexital (group M; n = 9) or isoflurane (group I; n = 9). We expected a better neurological outcome in animals administered methohexital because of superior neuronal protection and greater spinal cord perfusion pressure (mean arterial pressure below the cross-clamp site minus mean cerebrospinal fluid pressure). METHODS: After surgical preparation and a 30-minute stabilization period, dogs in group M received 14 +/- 6 mg.kg-1 i.v. methohexital to induce an isoelectric electroencephalogram followed by a continuous infusion of methohexital at 20 mg.kg-1 x h-1. Dogs in group I received 1.4 +/- 0.2% end-tidal isoflurane (1 minimum alveolar concentration). The thoracic aorta was then occluded 2.5 cm distal to the left subclavian artery for 30 minutes and then released. Hemodynamics and cerebrospinal fluid pressure were measured at (1) baseline, (2) 2 minutes after aortic cross-clamping, (3) 20 minutes after aortic cross-clamping, (4) 5 minutes after aortic unclamping, and (5) 30 minutes after resuscitation. At 24 hours a neurological assessment was performed. After the clinical assessment the dogs were killed and the spinal cord removed immediately for histopathologic study. RESULTS: There were no differences in nasopharyngeal temperature, PaCO2, pH, or hemoglobin at any time between groups. With cross-clamping, the spinal cord perfusion pressure decreased precipitously. However, there was no difference in spinal cord perfusion pressure between groups at any time (P = .5555). The neurological outcome, assessed at 24 hours after thoracic aortic cross-clamping by a veterinarian unaware of the anesthetic protocol, was not different between groups (P > .5, two-tailed Mann-Whitney rank- sums test). When anesthetized with methohexital 5 of 9 dogs were paraplegic; with isoflurane 7 of 9 dogs were paraplegic. By Spearman's rank test, a strong inverse correlation between the Tarlov score and the ratio of dead to total lumbar anterior spinal cord neurons was seen (Spearman's correlation coefficient = -.8358; P = .0001). CONCLUSIONS: We conclude that no advantage was offered by the choice of anesthesia to neurological outcome after 30 minutes of thoracic aortic cross- clamping in this canine model.

This article has been cited by other articles:

				R. A. Kahn, M. E. Stone, and D. M. Moskowitz Anesthetic Consideration for Descending Thoracic Aortic Aneurysm Repair Seminars in Cardiothoracic and Vascular Anesthesia, September 1, 2007; 11(3): 205 - 223. [Abstract] [PDF]

				M. Sakurai, T. Nagata, K. Abe, T. Horinouchi, Y. Itoyama, and K. Tabayashi Survival and death-promoting events after transient spinal cord ischemia in rabbits: Induction of Akt and caspase3 in motor neurons J. Thorac. Cardiovasc. Surg., February 1, 2003; 125(2): 370 - 377. [Abstract] [Full Text] [PDF]

				S. Kazama, Y. Miyoshi, M. Nie, H. Imai, Z. B. Lin, A. Kurata, and M. Machii Protection of the spinal cord with pentobarbital and hypothermia Ann. Thorac. Surg., May 1, 2001; 71(5): 1591 - 1595. [Abstract] [Full Text] [PDF]

				M. Sakurai, K. Abe, and K. Tabayashi Which cell does heat shock protein 72 induce? J. Thorac. Cardiovasc. Surg., March 1, 2001; 121(3): 598 - 599. [Full Text] [PDF]

				M. Sakurai, T. Hayashi, K. Abe, Y. Itoyama, K. Tabayashi, and W. I. Rosenblum Cyclin D1 and Cdk4 Protein Induction in Motor Neurons After Transient Spinal Cord Ischemia in Rabbits Editorial Comment Stroke, January 1, 2000; 31(1): 200 - 207. [Abstract] [Full Text] [PDF]

				G. S. Maharajh, E. A. Pascoe, W. C. Halliday, H. P. Grocott, D. B. Thiessen, L. G. Girling, M. S. Cheang, W. A. C. Mutch, and J. P. Muizelaar Neurological Outcome in a Porcine Model of Descending Thoracic Aortic Surgery: Left Atrial–Femoral Artery Bypass Versus Clamp/Repair Stroke, November 1, 1996; 27(11): 2095 - 2101. [Abstract] [Full Text]