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Gharagozloo F, Neville RF, Cox JL. Spinal cord protection during surgical procedures on the descending thoracic and thoracoabdominal aorta: a critical overview. Semin Thorac Cardiovasc Surg 1998; 10:73-86. [PMID: 9469783 DOI: 10.1016/s1043-0679(98)70022-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
During the past three decades, significant advances have been made in the surgical treatment of the diseases affecting the aorta. Despite these important advances, paraplegia remains a devastating complication of the surgical procedures on the thoracic and thoracoabdominal aorta. Paraparesis and paraplegia occur as a direct result of the interruption of blood flow to the spinal cord during the surgical procedures. A number of techniques have been advocated for the prevention of spinal cord ischemic injury. This article critically reviews our current understanding of the extent of this problem, the mechanism of injury, and the methods that have been devised to reduce the frequency of paraplegia following surgical procedures on the descending aorta.
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Affiliation(s)
- F Gharagozloo
- Georgetown Cardiovascular Institute, Georgetown University Medical Center, Washington, DC 20007, USA
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52
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Rokkas CK, Kouchoukos NT. Profound hypothermia for spinal cord protection in operations on the descending thoracic and thoracoabdominal aorta. Semin Thorac Cardiovasc Surg 1998; 10:57-60. [PMID: 9469780 DOI: 10.1016/s1043-0679(98)70019-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Elective hypothermic cardiopulmonary bypass with or without circulatory arrest has been used successfully for the treatment of complex aneurysms of the descending thoracic and thoracoabdominal aorta. Hypothermia has a protective effect on spinal cord function, and its use has been associated with a low incidence of paraplegia in traditionally high-risk patients. In our series, 96 consecutive patients underwent resection and graft replacement of diseased aortic segments of the distal aortic arch, the descending thoracic aorta, or the thoracoabdominal aorta. Thirty-day mortality was 7.3%, and the incidence of spinal cord ischemic injury was 3.4%. Our experience with hypothermic cardiopulmonary bypass and circulatory arrest confirms the safety and efficacy of the technique for operations on the descending thoracic and thoracoabdominal aorta.
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Affiliation(s)
- C K Rokkas
- Heart Center, Missouri Baptist Medical Center, St Louis, USA
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53
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Abstract
BACKGROUND Although rare, paralysis secondary to spinal cord ischaemia after aortic aneurysm surgery is a devastating complication. Many papers have been published on this topic but without a clear consensus on the best way of minimizing the problem. Recent articles have included advanced pharmacological approaches and the literature has been reviewed in light of these. METHODS Relevant papers were identified by an extensive text word search of the Medline database and a review of quoted articles. RESULTS Spinal cord complications are commoner after the repair of Crawford type II aneurysms than less extensive aneurysms. The presence of dissection, rupture and prolonged clamp times are associated with an increased incidence. About a quarter of all cord problems develop over 24 h after surgery and this may be due to a reperfusion type injury, although the exact mechanisms are by no means clear. CONCLUSION A combination of rapid surgery, left heart bypass for the repair of more extensive aneurysms, free spinal drainage and the avoidance of postoperative hypoxia and hypotension help to minimize spinal cord ischaemia. No pharmacological agent has yet been shown conclusively to improve outcome in the clinical setting.
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Affiliation(s)
- P Lintott
- Academic Surgical Unit, Imperial College School of Medicine at St Mary's, St Mary's Hospital, London, UK
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54
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Lange R, Thielmann M, Schmidt KG, Bauernschmitt R, Jakob H, Hasper B, Ulmer H, Hagl S. Spinal cord protection using hypothermic cardiocirculatory arrest in extended repair of recoarctation and persistent hypoplastic aortic arch. Eur J Cardiothorac Surg 1997; 11:697-702. [PMID: 9151040 DOI: 10.1016/s1010-7940(96)01114-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE In recurrent coarctation collateral circulation may not be sufficient to maintain adequate perfusion of the lower body during the period of surgical repair. Different techniques such as interposition of a Gott-shunt, use of left heart bypass or hypothermic cardiocirculatory arrest are used to prevent spinal cord injury. METHODS Twenty-eight operations for recurrent coarctation were performed in 26 patients following end-to-end anastomosis (58%), patch plasty (21%), subclavian flap aortoplasty (14%) and graft interposition (7%). Associated cardiac defects were present in 77% of the patients. Eleven patients who had adequate (> 50 mmHg) distal perfusion pressure during a test occlusion were operated on using simple cross-clamping (group I, mean age 8.5 +/- 3.8 years). In group I, end-to-end anastomosis was performed in nine patients and graft interposition in two patients. In 17 cases (including two patients from group I) with insufficient collateral circulation and with persistent hypoplasia of the arch, hypothermic cardiocirculatory arrest was used (group II, mean age 12.8 +/- 9.6 years). In group II end-to-end anastomosis was performed in three patients and graft interposition in 14 patients. Mean bypass-time was 116 +/- 36 min and arrest-time 33 +/- 16 min. Hypothermic cardiocirculatory arrest was begun when nasopharyngeal temperature was below 20 degrees C, corresponding to a rectal temperature of 24 +/- 3 degrees C. RESULTS Hypothermic cardiocirculatory arrest allowed open reconstruction of the arch and/or complete or partial replacement of the arch and the coarctation segment. In-hospital mortality was 0 and 5.9% in group I and II, respectively. The one patient who died in group II had simultaneous correction of an anomalous pulmonary venous connection and death was unrelated to the method of coarctation repair. Reversible laryngeal nerve paresis was observed in two patients in group II, no other neurologic complications were observed in either group. Postoperative gradients over the repair site were less than 20 mmHg by Doppler-echocardiography. Two patients of group I had to have a second, early reoperation because of stenosis at the anastomotic site. Reconstruction of the distal aortic arch was then performed during hypothermic cardiocirculatory arrest. CONCLUSIONS The use of hypothermic cardiocirculatory arrest in this special indication is a safe method which allows open reconstruction of the coarctation site and the aortic arch and protection of the spinal cord. The need for early reoperation because of inadequate repair may be reduced.
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Affiliation(s)
- R Lange
- Department of Cardiac Surgery, University of Heidelberg, Germany
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55
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Ishikawa M, Yamaguchi N, Bertalanffy H, Ohira T, Takase M, Kawase T, Toya S. Effects of spinal cord ischemia on the refractory period of descending spinal cord evoked potential. ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY 1997; 102:54-63. [PMID: 9060855 DOI: 10.1016/s0013-4694(96)96009-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The recovery cycle, following the conduction of action potentials along a nerve fiber, consists of the absolute refractory period (ARP), the relative refractory period (RRP) and the supernormal period (SNP). The recovery cycle of the descending conductive spinal cord evoked potential (SCEP) was shown during normal state, ischemia and after ischemia using paired stimuli in cats. During ischemia the refractory period revealed a trend towards increment. Five minutes after reperfusion the refractory period decreased transiently compared with the normal level and within 30 min the refractory period returned to the normal level. The recovery curve of the 2nd potential showed different pattern compared with that of the 1st potential. Moreover, during ischemia, firstly the 3rd potential and secondly the 2nd potential of the SCEP elicited by the 2nd stimulus were disturbed. These results demonstrated that there is increased excitability of the spinal cord to the second stimulus after a brief period of ischemia, and that the 2nd and 3rd potentials are evoked synaptically and easily disturbed during ischemia. Measuring the SCEP elicited by paired stimuli or constructing the recovery curve of the SCEP is useful for the electrophysiological assessment of spinal cord function.
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Affiliation(s)
- M Ishikawa
- Department of Neurosurgery, School of Medicine, Keio University, Tokyo, Japan
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56
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Aadahl P, Saether OD, Aakhus S, Bjørnstad K, Strømholm T, Myhre HO. The importance of transesophageal echocardiography during surgery of the thoracic aorta. Eur J Vasc Endovasc Surg 1996; 12:401-6. [PMID: 8980426 DOI: 10.1016/s1078-5884(96)80003-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVES To assess left ventricular dimensions and cardiac output during thoracic and thoracoabdominal aortic aneurysm repair. MATERIAL AND METHODS Nine patients undergoing thoracic and thoracoabdominal aneurysm repair using direct cross-clamping without shunt or by-pass were studied prospectively. Prior to, during cross-clamping (XC) and after declamping left ventricular cross-sectional areas were monitored with transesophageal echocardiography. A pulmonary artery catheter was used for measurements of cardiac output with the thermodilution technique. RESULTS Cardiac output increased 43% from baseline during XC (p < 0.01) and was still 55% above baseline at declamping (p < 0.05). Left ventricular end-systolic inner area was reduced 32% during XC (p < 0.01). Pulmonary artery pressures and central venous pressure increased during declamping (p < 0.05). Heart rate increased 38% from 66 beats/ min to 92 beats/min (p < 0.01) and was still 30% elevated at declamping (p < 0.01). CONCLUSION During thoracic aortic XC, cardiac output is increased and left ventricular end-systolic dimension is reduced. TEE is a valuable supplement to pressure measurements for the evaluation of cardiac function during surgery of the thoracic aorta.
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Affiliation(s)
- P Aadahl
- Department Anaesthesiology, University Hospital of Trondheim, Norway
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57
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Feldman Z, Gurevitch B, Artru AA, Oppenheim A, Shohami E, Reichenthal E, Shapira Y. Effect of magnesium given 1 hour after head trauma on brain edema and neurological outcome. J Neurosurg 1996; 85:131-7. [PMID: 8683262 DOI: 10.3171/jns.1996.85.1.0131] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Excitatory amino acids (EAA), mainly glutamate and aspartate, are released in excessive amounts from terminals of ischemic or traumatically injured neurons. These excessive levels of EAAs initiate a cascade of events believed to lead to secondary delayed damage to the surrounding brain. The N-methyl-D-aspartate receptor antagonists MK-801 and ketamine are reported to suppress excessive EAA release and to attenuate the development of focal brain edema following neuronal injury. Magnesium is also reported to work at the postsynaptic receptor to reduce the neurotoxic effect of glutamate. The present study was undertaken to examine the effect of postinjury treatment with Mg++ on brain edema and neurological outcome after traumatic brain injury. Sixty-nine rats that survived halothane anesthesia and closed head trauma (CHT) were randomly assigned to one of seven experimental groups: sham, CHT, and CHT with administration of Mg++ 1 hour postinjury. At 48 hours, brain tissue Mg++ concentration (calculated from optical density using a standard curve) was significantly increased compared to baseline levels (10.06 +/- 2.44 mg/g vs. 6.83 +/- 0.81 mg/g, p < 0.01 calculated by one-way analysis of variance). Also at 48 hours postinjury, brain tissue specific gravity in the contused hemisphere of Mg(++)-treated rats was significantly greater than that in the contused hemisphere of untreated rats, indicating attenuation of brain edema formation by Mg++. The neurological severity score (NSS) of rats treated with Mg++ improved significantly at both 18 and 48 hours, compared to baseline values obtained 1 hour after CHT but prior to administration of Mg++ (11.2 +/- 2.5 vs. 15.2 +/- 4.1, p = 0.03; and 12.3 +/- 6.1 vs. 17.3 +/- 3.6, p = 0.004, respectively). In the untreated groups, the NSS at 18 and 48 hours was not significantly different from baseline values (that is, no neurological improvement). The present study indicates that postinjury treatment with Mg++ attenuates brain edema formation and improves neurological outcome after experimental CHT.
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Affiliation(s)
- Z Feldman
- Department of Neurosurgery, Soroka Medical Center, Ben-Gurion University, Beer-Sheva, Israel
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58
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Gonzalez-Fajardo J, Beatriz A, Perez-Burkhardt JL, Alvarez T, Fernandez L, Ramos G, Vaquero C. Epidural regional hypothermia for prevention of paraplegia after aortic occlusion: experimental evaluation in a rabbit model. J Vasc Surg 1996; 23:446-52. [PMID: 8601886 DOI: 10.1016/s0741-5214(96)80009-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
PURPOSE The efficacy of epidural regional hypothermia in the prevention of acute and delayed-onset paraplegia, as well as possible complications and limitations of this technique to a clinically acceptable form, were evaluated in 49 New Zealand white rabbits. METHODS A modified rabbit spinal cord ischemia model of infrarenal aortic occlusion for 30 minutes was employed. The study was performed in two phases. In phase I (n=20), regional hypothermia induced by epidural perfusion of iced normal saline solution (4 degrees C) was tested versus control in 10 rabbits each (groups A and B). In phase II (n=29) the animals were subdivided into three groups to study the kinetics of absorbtion and distribution of methylene blue (group C; n=10), radiographic contrast material (group D; n=9), and measurement of cerebrospinal pressure while an epidural iced solution was or was not infused (group E; n=10). RESULTS At 24 and 48 hours, all of the normothermic animals showed irreversible paraplegia (Tarlov score 0). In contrast, at 24 hours none of the rabbits undergoing epidural cold infusion were paraplegic, although at 48 hours one animal had weakness of a hindlimb (Tarlov score 3). Plasma concentration-time profiles of a continuous epidural perfusion with methylene blue showed that the spinal canal is a highly compliant space. Epidurographs showed that epidural perfusion tends to spread more in a cephalic than caudal direction and the main uptake is by the vascular compartment. Despite the large volumes infused (78.75 ml/hr; range, 50 to 100 ml), we observed only a modest transient increase in cerebrospinal fluid pressure (from 2.5 +/- 0.3 mm Hg to 5.4 +/- 0.1 mm Hg), although some animals had intracranial hypertension. CONCLUSIONS Regional hypothermia induced by epidural cold perfusion has a highly protective effect against the ischemic spinal cord damage. However, this method probably does not avoid the risk of delayed-onset paraplegia. An important limitation of this technique is the difficulty of controlling the intrathecal pressures.
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59
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Gharagozloo F, Larson J, Dausmann MJ, Neville RF, Gomes MN. Spinal cord protection during surgical procedures on the descending thoracic and thoracoabdominal aorta: review of current techniques. Chest 1996; 109:799-809. [PMID: 8617093 DOI: 10.1378/chest.109.3.799] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Affiliation(s)
- F Gharagozloo
- Division of Cardiovascular and Thoracic Surgery, Georgetown University School of Medicine, Washington, DC 20007, USA
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60
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Koç RK, Akdemir H, Kurtsoy A, Paşaoğlu H, Kavuncu I, Paşaoğlu A, Karaküçük I. Lipid peroxidation in experimental spinal cord injury. Comparison of treatment with Ginkgo biloba, TRH and methylprednisolone. RESEARCH IN EXPERIMENTAL MEDICINE. ZEITSCHRIFT FUR DIE GESAMTE EXPERIMENTELLE MEDIZIN EINSCHLIESSLICH EXPERIMENTELLER CHIRURGIE 1995; 195:117-23. [PMID: 7659833 DOI: 10.1007/bf02576781] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Ischaemia-induced lipid peroxidation is one of the most important factors producing tissue damage in spinal cord injury. In our study, the protective effects of Ginkgo biloba, thyroid releasing hormone (TRH) and methylprednisolone (MP) on compression injury of the rat spinal cord were investigated. For this study 45 rats in four groups, including control, MP, TRH and Gingko biloba, were used to determine the formation of malondialdehyde (MDA). All the animals were made paraplegic by the application clip method of Rivlin and Tator. Rats were divided randomly and blindly to one of four treatment groups (ten animals in each). MP and Ginkgo biloba treatments significantly decreased MDA levels (F = 54.138, P < 0.01). These results suggest that MP and Ginkgo biloba may have a protective effect against ischaemic spinal cord injury by the antioxidant effect.
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Affiliation(s)
- R K Koç
- Department of Neurosurgery, Erciyes University, School of Medicine, Kayseri, Turkey
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61
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Hypothermic bypass and circulatory arrest for operations on the descending thoracic and thoracoabdominal aorta. Ann Thorac Surg 1995. [DOI: 10.1016/s0003-4975(95)00353-3] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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62
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Abstract
Spinal cord ischemia, as represented by acute paraplegia, is rare in the absence of trauma. It is even more uncommon that an infarction of the spinal cord occurs in a patient with no predisposition to vascular disease. We report a case of anterior spinal artery syndrome resulting from an infarction of the anterior aspect of the spinal cord in an otherwise healthy 45-year-old woman.
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Affiliation(s)
- T J Gaeta
- Department of Emergency Medicine, Lincoln Hospital, Bronx, New York, USA
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63
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Malatová Z, Vanický I, Gálik J, Marsala M. Epidural perfusion cooling protects against spinal cord ischemia in rabbits. An evaluation of cholinergic function. MOLECULAR AND CHEMICAL NEUROPATHOLOGY 1995; 25:81-96. [PMID: 8534329 DOI: 10.1007/bf02960903] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The protective effect of regional epidural spinal cord cooling was evaluated in a rabbit spinal cord ischemia model. Hypothermia was performed by the continual perfusion of 2-4 degrees C cold saline in the epidural space around the ischemic lumbar segments, 4 min before and during ischemia. The spinal cord was deeply hypothermic (21 degrees C) throughout the whole ischemic period. Ischemia was induced by the occlusion of the abdominal aorta for 40 min under normothermic or hypothermic conditions. Recovery of motor and sensory functions, spinal cord-evoked potentials, and motor-evoked potentials were then evaluated up to 24 h postischemia. After this period, choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) activities were measured, in particular, zones of the lumbar spinal cord. AChE was also investigated histochemically. Animals in the normothermic group displayed fully developed spastic paraplegia with near complete loss of spinal somatosensory and motor-evoked potentials. AChE histochemistry showed extensive necrotic changes affecting lumbosacral gray matter. These changes corresponding with the pronounced losses of ChAT and AChE activities indicated irreversible injury of the spinal cord. In contrast, after hypothermic ischemia, animals survived without any sign of neurological impairment with almost full recovery of the spinal cord-evoked potentials. ChAT and AChE activities in the gray matter showed near control values corresponding with histochemical analysis of fully preserved gray matter. Hypothermia under the present experimental conditions efficiently protected the spinal cord against ischemic injury.
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Affiliation(s)
- Z Malatová
- Institute of Neurobiology, Slovak Academy of Sciences, Kosice, Slovak Republic
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64
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Mauney MC, Blackbourne LH, Langenburg SE, Buchanan SA, Kron IL, Tribble CG. Prevention of spinal cord injury after repair of the thoracic or thoracoabdominal aorta. Ann Thorac Surg 1995; 59:245-52. [PMID: 7818342 DOI: 10.1016/0003-4975(94)00815-o] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Spinal cord injury occurring as the result of surgical repair of thoracic and thoracoabdominal aortic disease remains a devastating complication. The incidence of postoperative neurologic deficits varies from 4% to 38%. Factors associated with a greater risk for injury include the presence of dissection or extensive thoracoabdominal disease, and a prolonged cross-clamp time. Spinal cord ischemia initiates a deleterious cascade of biochemical events that ultimately result in an increased intracellular calcium concentration. Calcium-activated proteases, lipases, and nucleases mediate the processes that cause cell injury. The accumulation of oxygen-derived free radicals and the occurrence of hyperemia during reperfusion are also contributing causes of spinal cord injury. Increasing the spinal cord blood flow with shunts, oxygenated bypass circuits, cerebrospinal fluid drainage, the intrathecal administration of vasodilators, and the reattachment of intercostal arteries has been tried in an effort to increase spinal cord perfusion. Pharmacologically based measures to prevent spinal cord injury have been pursued, and these have consisted of hypothermia, anesthetic agents, calcium channel blockers, free radical scavengers, and immune system modulation. However, no single technique has proved to be consistently effective in preventing ischemia-induced spinal cord injury.
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Affiliation(s)
- M C Mauney
- Department of Surgery, University of Virginia Health Sciences Center, Charlottesville 22908
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65
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Grabenwöger M, Ehrlich M, Simon P, Grimm M, Laufer G, Wollenek G, Mares P, Wolner E, Havel M. Thoracoabdominal aneurysm repair: spinal cord protection using profound hypothermia and circulatory arrest. J Card Surg 1994; 9:679-84. [PMID: 7841648 DOI: 10.1111/j.1540-8191.1994.tb00902.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Between January 1991 and February 1993, 14 patients (11 male, 3 female) between 21 and 79 years of age (median 50 years) underwent reconstruction of the thoracic (n = 7) and thoracoabdominal aorta (n = 7). Four patients had previously undergone operation of the ascending aorta, and in three patients coronary artery bypass grafting had previously been performed. All patients were operated on a via a posterolateral thoracotomy using cardiopulmonary bypass with continuous blood cardioplegia and hypothermic circulatory arrest (11 degrees C nasopharyngeal temperature, flat-EEG). All patent lower intercostal and lumbar arteries (T3 to L5) were reimplanted. The 30-day mortality after repair of the thoracic aorta was 0%; after replacement of the thoracoabdominal aorta, mortality was 28.5% (n = 2). One patient died 70 days after replacement of the thoracic aorta as a consequence of a perioperative stroke. None of the surviving 11 patients developed a permanent neurological deficit or renal or cardiac dysfunction. The average intensive care stay was 6 days for patients after replacement of the thoracic aorta and 18 days for patients after replacement of the thoracoabdominal aorta. Our results suggest that use of elective hypothermia and circulatory arrest for spinal cord protection is highly effective. We, therefore, recommend this method for complex reconstructions of the thoracoabdominal aorta.
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Affiliation(s)
- M Grabenwöger
- Department of Cardio-Thoracic Surgery, University of Vienna, Austria
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66
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Forbes AD, Slimp JC, Winn RK, Verrier ED. Inhibition of neutrophil adhesion does not prevent ischemic spinal cord injury. Ann Thorac Surg 1994; 58:1064-8. [PMID: 7944751 DOI: 10.1016/0003-4975(94)90456-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Paraplegia may occur after transient aortic occlusion as a consequence of primary ischemia to the spinal cord or injury during the reperfusion period. In animal models of ischemia/reperfusion there is evidence that reperfusion injury may be modulated partially by neutrophils. The efficacy of the neutrophil adherence blocking murine monoclonal antibody (MAb 60.3) was assessed in spinal cord ischemia/reperfusion in rabbits. Spinal cord ischemia was accomplished by balloon catheter occlusion of the infrarenal aorta. Neurologic assessment was graded as normal, partial neurologic deficit, or complete paralysis. Electrophysiologic monitoring with somatosensory evoked potentials was used to determine the optimal length of time of occlusion. Animals were treated randomly with 2 mg/kg of intravenous Mab 60.3 (n = 8) or saline solution (n = 9) with the investigator unaware of treatment. Mean occlusion times were no different between groups (control, 32.7 +/- 3.6 minutes versus MAb, 32.4 +/- 6.0 minutes). Five (55%) saline-treated and four (50%) MAb 60.3-treated animals became paraplegic. Animals with initial paraparesis all progressed to flaccid paraplegia within 24 hours. We conclude that spinal cord injury after transient aortic occlusion is independent of the CD11/CD18 glycoprotein complex of the neutrophil. Injury in this setting may occur during ischemia and thus may not be dependent on neutrophils or reperfusion.
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Affiliation(s)
- A D Forbes
- Division of Cardiothoracic Surgery, University of Washington, Seattle 98195
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67
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Marsala M, Vanicky I, Yaksh TL. Effect of graded hypothermia (27 degrees to 34 degrees C) on behavioral function, histopathology, and spinal blood flow after spinal ischemia in rat. Stroke 1994; 25:2038-46. [PMID: 8091450 DOI: 10.1161/01.str.25.10.2038] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND AND PURPOSE We used a rat model of reversible spinal ischemia to assess the effect of spinal cord temperature on the development of neurological and histopathologic changes after 20 minutes of reversible aortic occlusion. Spinal cord blood flow and CO2 reactivity was tested by using laser Doppler before and 60 minutes after ischemia. METHODS In halothane (1%)-anesthetized rats, the spinal cord temperature as assessed by using thermocouple in the paraspinal muscles was lowered to 34 degrees, 31 degrees, or 27 degrees C. After ischemia, spinal cord temperature was raised to 37 degrees C for the next 30 minutes. Animals were maintained in this normothermic condition for 8 hours, after which motor and sensory function were assessed. All animals were then anesthetized and perfused with 10% formalin for light microscopic analysis of spinal cords. RESULTS In normothermic animals, 20 minutes of ischemia resulted in a loss of CO2 reactivity and hind limb paraplegia with an attendant allodynia that persisted for the 8 hours of reperfusion. Even mild (34 degrees C) hypothermia resulted in significant improvement of neurological function compared with the normothermic group. In paraplegic animals, lumbosacral interneuronal pools localized primarily in laminae III through VII displayed heavy argyrophilic neurons and areas of localized necrosis. In moderate and deep hypothermic animals preservation of CO2 responsivity and complete recovery of neurological function were seen with no detectable histopathologic changes. CONCLUSIONS These results show that a slight decrease in spinal cord temperature in the peri-ischemic period provides significant protection as measured by histopathology and neurological function.
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Affiliation(s)
- M Marsala
- Department of Anesthesiology, University of California, San Diego, La Jolla 92093
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68
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Follis F, Miller K, Scremin OU, Pett S, Kessler R, Wernly J. NMDA receptor blockade and spinal cord ischemia due to aortic crossclamping in the rat model. Neurol Sci 1994; 21:227-32. [PMID: 8000978 DOI: 10.1017/s0317167100041202] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Recent brain research proposes that, during ischemia, synaptically released excitatory amino acid neurotransmitters accumulate at toxic concentrations with ensuing neuronal death. Their action is mediated by the receptor subtype N-methyl-D-aspartate (NMDA). The protective effect of NMDA receptor blockade with intrathecal MgSO4 and MK-801 was investigated during spinal cord ischemia induced by aortic occlusion of 12 minutes. Male Sprague-Dawley rats, 250-300g, underwent intrathecal administration of 20 microL of normal saline (SA n = 16), MgSO4 1M (MG n = 16), or MK-801, 25 mM solutions (MK n = 16) in a randomized order. After 2 hours, the animals underwent occlusion of the thoracic aorta and subclavian arteries for 12 min. An additional control group (CO n = 16) underwent occlusion for 12 minutes, without intrathecal injection. The animals were scored according to their functional performance (LS = lesion score) each day for four days by a blinded observer. Mean LS were calculated for each group at a given day. Treatment and control groups were not different at day 1 (P = 0.302). Group MG was improved from groups SA (P = < 0.0039) and CO (P = < 0.0048) at day 4. This study demonstrates that although intrathecal NMDA receptor blockade with MgSO4 or MK-801 does not prevent paraplegia due to spinal cord ischemia in the rat, it could however influence the rate of recovery after ischemic injury.
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Affiliation(s)
- F Follis
- Department of Thoracic and Cardiothoracic Surgery, University of New Mexico, Albuquerque 87131
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Ueno T, Furukawa K, Katayama Y, Suda H, Itoh T. Spinal cord protection: development of a paraplegia-preventive solution. Ann Thorac Surg 1994; 58:116-20. [PMID: 8037508 DOI: 10.1016/0003-4975(94)91083-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We present a clinically available method to protect the spinal cord against ischemic or reperfusion injury and to prevent paraplegia after cross-clamping of the aorta. We separated 35 rabbits into five equal groups and clamped each animal's abdominal aorta distal to the left renal artery. We also occluded the aortas 2 cm above the iliac bifurcation for 45 minutes with inflated 5F balloon catheters. Through the catheter port distal to each balloon one of four different solutions was infused at 3 degrees C for 3 minutes at a rate of 5 mL/min (group I, uninfused control; group II, lactated Ringer's solution; group III, lactated Ringer's solution + 30 mg/kg of methylprednisolone; group IV, lactated Ringer's solution+methylprednisolone + 3 mL of 20% mannitol; group V, lactated Ringer's solution+methylprednisolone+mannitol + 10 mg/kg of vitamins E and C). We assessed the neurologic status of the hind limbs on the second postoperative day using Tarlov's criteria. The neurologic status in groups III, IV, and V was significantly superior to that of group I (p < 0.05, groups III versus I; p < 0.01, groups IV and V versus I). Spastic paraplegia occurred in 71% of group I, in 43% of group II, in 29% of group III, in 14% of group IV, and not at all in group V. The infusion of our specially blended solution with several spinal cord neuroprotective properties (hypothermia, methylprednisolone, mannitol, and vitamins E and C) achieved the best spinal cord protection against ischemic or reperfusion injury and prevented postoperative paraplegia.
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Affiliation(s)
- T Ueno
- Department of Surgery, Saga Medical School, Japan
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70
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Wisselink W, Becker MO, Nguyen JH, Money SR, Hollier LH. Protecting the ischemic spinal cord during aortic clamping: the influence of selective hypothermia and spinal cord perfusion pressure. J Vasc Surg 1994; 19:788-95; discussion 795-6. [PMID: 8170032 DOI: 10.1016/s0741-5214(94)70003-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSE We verified the hypothesis that selective deep hypothermia of the spinal cord during double thoracic aortic clamping can prevent postoperative paraplegia in dogs. METHODS Normal saline solution was circulated from the cisterna magna through an extracorporeal perfusion system consisting of a reservoir, a pump, and a heat exchanger, back into the subarachnoid space at the level of the medullary cone at a rate of 25 ml/min, starting 30 minutes before clamping, and ending after removal of the clamps. The thoracic aorta was cross-clamped below the left subclavian artery and above the diaphragm for a period of 45 minutes. Cerebrospinal fluid, intracranial, and central venous pressure and aortic pressure proximal, between, and distal to the clamps were continuously recorded. In five dogs, temperature of the circulating normal saline solution at the inflow level was maintained at 2 degrees +/- 1.5 degrees C (group 1), in five controls at 37 degrees +/- 0.8 degrees C (group 2). Five dogs underwent continuous cerebrospinal fluid drainage starting before clamping until sacrifice (group 3). Dogs were observed for up to 4 days, and neurologic function was graded by an independent observer with the Tarlov scale. Animals were then killed, and their spinal cords were prepared for microscopic examination. RESULTS Hemodynamic parameters were not significantly different between groups. All dogs in groups 2 and 3 were paraplegic with histologic evidence of spinal cord infarction. All animals in group 1 were neurologically normal without microscopic evidence of infarction (p < 0.005). CONCLUSIONS Selective deep hypothermia of the spinal cord prevents paraplegia after 45 minutes of double aortic clamping in dogs. Cerebrospinal fluid drainage was not effective in preventing paraplegia in this model.
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Affiliation(s)
- W Wisselink
- Department of Surgery, Ochsner Clinic, New Orleans, Louisiana
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71
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Ueno T, Furukawa K, Katayama Y, Itoh T. Protection against ischemic spinal cord injury: one-shot perfusion cooling and percutaneous topical cooling. J Vasc Surg 1994; 19:882-7. [PMID: 8170043 DOI: 10.1016/s0741-5214(94)70014-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSE We investigated the protective effect of two methods of hypothermia against ischemic spinal cord injury: one-shot perfusion cooling and percutaneous topical cooling. METHODS Twenty-five rabbits were divided into five equal groups. The abdominal aorta was isolated proximally by a vascular clamp and distally by an inflated balloon catheter for 60 minutes. Group I served as control. In groups II (2.5 ml/min) and III (5.0 ml/min), hypothermic lactated Ringer's solution was infused for 3 minutes from the distal end of the catheter. Ice blocks were placed behind the backs of rabbits 30 minutes before ischemia in group IV. Group V underwent the procedures combined with those in groups II and IV (infusion of hypothermic solution plus placement of ice blocks). Another 15 rabbits underwent laminectomy at the L2 or L3 level. A temperature probe was inserted into the spinal cord to monitor cord temperature continuously during the procedures in all five groups (three rabbits per group). RESULTS Neurologic status on the second postoperative day in groups IV and V was significantly superior to that in group I (p < 0.01), but the neurologic status of groups II and III did not differ significantly from the neurologic status of group I. The spinal cord temperature in groups II and III dropped rapidly with the infusion, but it rose again quickly. In contrast, the spinal cord was kept sufficiently hypothermic during ischemia in groups IV and V. CONCLUSIONS We concluded that the percutaneous cooling method can keep the spinal cord sufficiently hypothermic during ischemia to lead to a significantly superior neurologic outcome.
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Affiliation(s)
- T Ueno
- Department of Surgery, Saga Medical School, Japan
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72
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Marsala M, Yaksh TL. Transient spinal ischemia in the rat: characterization of behavioral and histopathological consequences as a function of the duration of aortic occlusion. J Cereb Blood Flow Metab 1994; 14:526-35. [PMID: 8163596 DOI: 10.1038/jcbfm.1994.65] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To characterize the behavioral and histopathological changes that occur in spinal cord after transient ischemia, reversible occlusion of the descending aorta was achieved in the halothane (1-1.5%)-anesthetized rat by the insertion and subsequent inflation of a 2F Fogarty catheter for 10, 15, 20, or 30 min. Neurological recovery was tested during 8 h of reperfusion. After reflow, animals undergoing 30 min of ischemia displayed an initial flaccidity at 1 h, spasticity at 4 h, and flaccidity at the end of 8 h. Following 20 min of ischemia the initial flaccidity was followed by hindlimb spasticity that persisted for 8 h. Shorter intervals of ischemia had minimal effects on motor function. After reflow, animals developed a prominent allodynea, the incidence of which was dependent on the duration of ischemia. A clear correlation of histopathological changes with the degree of neurological deficit was noted. In spastic animals, small and medium-sized interneurons localized in laminae III to VII were affected. Animals with flaccidity at 8 h additionally displayed a significant incidence of argyrophilic A motoneurons in the ventral horns. Corresponding to the frequent appearance of allodynea, these animals also showed a significant number of damaged neurons in lamina II.
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Affiliation(s)
- M Marsala
- Institute of Neurobiology, Slovak Academy of Sciences, Kosice
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73
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Frank SM, Parker SD, Rock P, Gorman RB, Kelly S, Beattie C, Williams GM. Moderate hypothermia, with partial bypass and segmental sequential repair for thoracoabdominal aortic aneurysm. J Vasc Surg 1994; 19:687-97. [PMID: 8164285 DOI: 10.1016/s0741-5214(94)70043-5] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSE Ischemic injury to the spinal cord, kidneys, and viscera occurs in a significant number of patients undergoing surgical repair of thoracoabdominal aortic aneurysms. Partial bypass has been used to perfuse the arterial system distal to the cross-clamp, but the primary determinant of ischemic morbidity remains the duration of aortic cross-clamping. Hypothermia may favorably affect outcome during these procedures, but moderate or deep hypothermia has traditionally required full cardiopulmonary bypass with cardiac arrest. METHODS In a series of patients undergoing thoracoabdominal (n = 14) or thoracic (n = 4) aneurysm repair, we used moderate hypothermia (30 degrees C) and partial bypass (aortofemoral or atriofemoral) while maintaining an intrinsic cardiac rhythm. Body temperature was controlled with a heat exchanger in the bypass circuit, which allowed for rapid cooling and rewarming. In addition to hypothermia and bypass, a segmental sequential surgical repair was used to minimize the duration of ischemia to any given vascular bed. RESULTS All patients survived the surgical procedure, and 16 patients survived until discharge from the hospital. None of the 18 patients had paraplegia or significant renal dysfunction. The only complication related to hypothermia was atrial fibrillation, which occurred in three patients and was amenable to therapeutic measures. CONCLUSIONS We conclude that moderate hypothermia, partial bypass, and segmental sequential repair may reduce ischemic injury. This combination of adjuncts was not associated with significant complications in this series of patients.
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Affiliation(s)
- S M Frank
- Department of Anesthesiology, Johns Hopkins Hospital, Baltimore, MD 21287
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74
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Herold JA, Kron IL, Langenburg SE, Blackbourne LH, Tribble CG. Complete prevention of postischemic spinal cord injury by means of regional infusion with hypothermic saline and adenosine. J Thorac Cardiovasc Surg 1994. [DOI: 10.1016/s0022-5223(12)70100-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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75
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Francel PC, Long BA, Malik JM, Tribble C, Jane JA, Kron IL. Limiting ischemic spinal cord injury using a free radical scavenger 21-aminosteroid and/or cerebrospinal fluid drainage. J Neurosurg 1993; 79:742-51. [PMID: 8410254 DOI: 10.3171/jns.1993.79.5.0742] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Traumatic spinal cord injury occurs in two phases: biomechanical injury, followed by ischemia and reperfusion injury. Biomechanical injury to the spinal cord, preceded or followed by various pharmaceutical manipulations or interventions, has been studied, but the ischemia/reperfusion aspect of spinal cord injury isolated from the biomechanical injury has not been previously evaluated. In the current study, ischemia to the lumbar spinal cord was induced in albino rabbits via infrarenal aortic occlusion, and two interventions were analyzed: the use of U74006F (Tirilazad mesylate), a 21-aminosteroid, and cerebrospinal fluid (CSF) drainage. These treatment modalities were tested alone or in combination. In Phase 1 of this study, the rabbits received 1.0 mg/kg of Tirilazad or an equal volume of vehicle (controls) prior to the actual occlusion, three doses of Tirilazad (1 mg/kg each) during the occlusion, then several doses after the occlusion. Of the Tirilazad-treated animals, 30% became paraplegic while 70% of the control animals became paraplegic. Phase 2 involved the same doses of Tirilazad as in Phase 1 and, in addition, CSF pressure monitoring and drainage were performed. The paraplegia rate was 79% in the control animals, 36% in the group receiving Tirilazad alone, 25% in the group with CSF drainage alone, and 20% in the Tirilazad plus CSF drainage group. This rate also correlated with changes noted in CSF pressure; both Tirilazad administration alone and CSF drainage alone induced a decrease in CSF pressure and the two combined produced a further decrease. There was marked improvement in the perfusion pressure when using Tirilazad alone, CSF drainage alone, and Tirilazad therapy in combination with CSF drainage, with the last group producing the largest increase. This change in CSF pressure and perfusion pressure correlated with improved functional neurological outcome. Pathological examination revealed that Tirilazad therapy reduced the extensive and diffuse neuronal, glial, and endothelial damage to (in its most severe form) a more patchy focal region of damage in the gray matter. Cerebrospinal fluid drainage resulted in pyknosis of some motor neurons, and some eosinophilia. The combination of CSF drainage and Tirilazad administration resulted in the least abnormality, with either normal or near-normal spinal cords. It is concluded that Tirilazad administration decreased CSF pressure during spinal cord ischemia and reperfusion and, like CSF drainage, increased and improved the perfusion pressure to the spinal cord, decreased spinal cord damage, and improved functional outcome.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- P C Francel
- Department of Neurosurgery, University of Virginia Health Sciences Center, Charlottesville
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76
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Vanický I, Marsala M, Gálik J, Marsala J. Epidural perfusion cooling protection against protracted spinal cord ischemia in rabbits. J Neurosurg 1993; 79:736-41. [PMID: 8410253 DOI: 10.3171/jns.1993.79.5.0736] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The protective effect of a modified epidural cooling technique was assessed in a rabbit spinal cord ischemia model. The epidural space around the lumbar segments with induced ischemia was continually perfused with cold (5 degrees C) isotonic saline via two communicating spinal canal openings. This procedure allowed the spinal cord to be kept deeply hypothermic (< 15 degrees C within central gray matter) during the ischemic period. The animals were subjected to either normothermic ischemia (Group A) or hypothermic ischemia (Group B). Each group contained three subgroups of animals undergoing 20, 40, or 60 minutes of aortic ligation. Their neurological outcomes were evaluated up to 48 hours postischemia, and the intergroup differences were compared. Two days postischemia, all of the animals were sacrificed by transcardial perfusion-fixation and their lumbar segments were processed for histopathological examination. In addition, in animals with 60-minute ischemia, spinal somatosensory evoked potentials were recorded during surgical intervention and again after 48 hours. In the normothermic animals, a high incidence of paraplegia was detected: in 40% after 20 minutes of ischemia, in 75% after 40 minutes, and in 100% after 60 minutes. In contrast, all of the hypothermic animals exhibited full neurological recovery even after 60 minutes of ischemia. Both electrophysiological and histological observations clearly correlated with the neurological findings. The results suggest that deep spinal cord hypothermia produced by epidural perfusion cooling provides effective protection against protracted spinal cord ischemia in rabbits.
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Affiliation(s)
- I Vanický
- Institute of Neurobiology, Slovak Academy of Sciences, Kosice
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77
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Tabayashi K, Niibori K, Konno H, Mohri H. Protection from postischemic spinal cord injury by perfusion cooling of the epidural space. Ann Thorac Surg 1993; 56:494-8. [PMID: 8379721 DOI: 10.1016/0003-4975(93)90885-l] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
To avoid devastating spinal cord injury during aneurysm operations, we evaluated the protective effects of epidural space perfusion cooling during occlusion of the descending thoracic aorta in a canine model. Sixteen dogs were divided into three groups: group 1 (n = 5) underwent 60 minutes of aortic occlusion without epidural space perfusion cooling; group 2 (n = 6), 60 minutes of occlusion with perfusion cooling; and group 3 (n = 5), 120 minutes of occlusion with perfusion cooling. The development of motor disturbance and its severity were examined 7 days after the procedure. In group 1, 1 dog was normal and 4 dogs showed spastic paraplegia with rigidly extended hind limbs. In group 2, 5 dogs were normal and 1 dog was unable to walk although it could move both of its hind legs slightly. In group 3, all 5 dogs were normal. Groups 2 and 3 had a significantly better neurologic outcome than group 1. Histologic examination of the spinal cord in dogs with paraplegia revealed degeneration of gray matter with macrophage infiltration. Histologic examination of the spinal cord in dogs without neurologic deficit showed enlargement of the central canal, light edema, and a small number of dark neurons. We conclude that epidural space perfusion cooling is effective in reducing the incidence of spinal cord injury after temporary occlusion of the descending thoracic aorta.
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Affiliation(s)
- K Tabayashi
- Department of Thoracic and Cardiovascular Surgery, Tohoku University School of Medicine, Miyagi, Japan
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78
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Smith DH, Okiyama K, Gennarelli TA, McIntosh TK. Magnesium and ketamine attenuate cognitive dysfunction following experimental brain injury. Neurosci Lett 1993; 157:211-4. [PMID: 8233056 DOI: 10.1016/0304-3940(93)90739-8] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We evaluated the therapeutic effects of two noncompetitive antagonists of the N-methyl-D-aspartate (NMDA) receptor, MgCl2 and ketamine, both individually and together, on cognitive dysfunction observed following parasagittal fluid-percussion (FP) brain injury in the rat. Using a modified Morris water maze technique, we found significant attenuation of post-traumatic memory dysfunction in animals treated with either MgCl2 (125 mumol) or ketamine (4 mg/kg) (P < 0.005). Combined MgCl2 and ketamine treatment also preserved memory function (P < 0.005), with no apparent additive effect.
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Affiliation(s)
- D H Smith
- Division of Neurosurgery, University of Pennsylvania, Philadelphia 19104
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79
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Affiliation(s)
- S A Shenaq
- Department of Anesthesiology and Surgery, Baylor College of Medicine, Houston, TX 77030
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80
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Svensson LG, Crawford ES. Aortic dissection and aortic aneurysm surgery: clinical observations, experimental investigations, and statistical analyses. Part III. Curr Probl Surg 1993; 30:1-163. [PMID: 8440132 DOI: 10.1016/0011-3840(93)90009-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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81
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McIntosh TK. Novel pharmacologic therapies in the treatment of experimental traumatic brain injury: a review. J Neurotrauma 1993; 10:215-61. [PMID: 8258838 DOI: 10.1089/neu.1993.10.215] [Citation(s) in RCA: 197] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Delayed or secondary neuronal damage following traumatic injury to the central nervous system (CNS) may result from pathologic changes in the brain's endogenous neurochemical systems. Although the precise mechanisms mediating secondary damage are poorly understood, posttraumatic neurochemical changes may include overactivation of neurotransmitter release or re-uptake, changes in presynaptic or postsynaptic receptor binding, or the pathologic release or synthesis of endogenous "autodestructive" factors. The identification and characterization of these factors and the timing of the neurochemical cascade after CNS injury provides a window of opportunity for treatment with pharmacologic agents that modify synthesis, release, receptor binding, or physiologic activity with subsequent attenuation of neuronal damage and improvement in outcome. Over the past decade, a number of studies have suggested that modification of postinjury events through pharmacologic intervention can promote functional recovery in both a variety of animal models and clinical CNS injury. This article summarizes recent work suggesting that pharmacologic manipulation of endogenous systems by such diverse pharmacologic agents as anticholinergics, excitatory amino acid antagonists, endogenous opioid antagonists, catecholamines, serotonin antagonists, modulators of arachidonic acid, antioxidants and free radical scavengers, steroid and lipid peroxidation inhibitors, platelet activating factor antagonists, anion exchange inhibitors, magnesium, gangliosides, and calcium channel antagonists may improve functional outcome after brain injury.
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Affiliation(s)
- T K McIntosh
- Department of Surgery, University of Pennsylvania, Philadelphia
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82
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Svensson LG, Crawford ES. Aortic dissection and aortic aneurysm surgery: clinical observations, experimental investigations, and statistical analyses. Part II. Curr Probl Surg 1992; 29:913-1057. [PMID: 1291195 DOI: 10.1016/0011-3840(92)90003-l] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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83
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Svensson LG, Crawford ES. Aortic dissection and aortic aneurysm surgery: clinical observations, experimental investigations, and statistical analyses. Part I. Curr Probl Surg 1992; 29:817-911. [PMID: 1464240 DOI: 10.1016/0011-3840(92)90019-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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84
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Fercakova A, Halat G, Marsala M, Lukacova N, Marsala J. Graded postischemic reoxygenation reduces lipid peroxidation and reperfusion injury in the rabbit spinal cord. Brain Res 1992; 593:159-67. [PMID: 1450926 DOI: 10.1016/0006-8993(92)91304-w] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effect of graded postischemic reoxygenation on lipid peroxidation, neurological recovery and the degree of spinal cord damage after 20 min abdominal aorta ligature was tested in the rabbit. In comparison with normoxic recirculation, the graded postischemic reoxygenation (GPIR) during early phase of reperfusion (30 min) significantly reduced the level of lipid peroxidation products (LPP) in vivo and in vitro after 1 h survival. Neuropathological changes in animals with normoxic reperfusion showed gradual deterioration ranging from appearance of heavy argyrophilic neurons after 1 h reperfusion followed by neuronal necroses after 12 h survival to the development of an extensive spongy lesion reaching ventral horn and intermediate zone 2 days postoperatively. The neuroprotective effect of graded postischemic reoxygenation was evident even after 2 days survival with preserved structural integrity of the gray matter as confirmed by light and electron microscopy. The results indicate that graded postischemic reoxygenation during 1 h reperfusion can reduce lipid peroxidation and suppress irreversible neuronal damage using developing during the early reperfusion phase.
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Affiliation(s)
- A Fercakova
- Institute of Neurobiology, Slovak Academy of Sciences, Kosice
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85
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86
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Abstract
Surgical resection of the descending thoracic and thoracoabdominal aorta is associated with the risk of spinal cord ischemic injury, particularly in patients with aortic dissection. Hypothermic total cardiopulmonary bypass with periods of circulatory arrest has been advocated for spinal cord protection with encouraging early results. However, techniques for this procedure are relatively complex. An alternative cannulation technique with venous return from the right atrium through the internal jugular vein and arterial return to the aortic arch is described. This has been used in 6 patients for replacement of the descending thoracic or thoracoabdominal aorta. Despite profound hypothermia and preservation of the principal spinal radicular artery, 1 patient suffered early paraparesis with some recovery but eventually died of multisystem failure. A second elderly patient with severe obstructive airways disease died of respiratory failure 11 days postoperatively. Four patients made a good recovery including 1 with a ruptured thoracoabdominal aneurysm who subsequently required gut resection for ischemic necrosis present preoperatively. This cannulation technique together with profound hypothermia has greatly improved the operating conditions for extensive aneurysms of the thoracoabdominal aorta. Paraparesis occurring despite hypothermic protection and attempted preservation of the spinal cord arterial supply suggests that unfavorable vascular anatomy still predominates in the risk factors for ischemic injury.
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Affiliation(s)
- S Westaby
- Oxford Heart Centre, John Radcliffe Hospital, England
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87
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Okamoto Y, Suzuki T, Murayama S. Effects of naloxone and levallorphan on the spinal cord reflex potentials under the spinal ischemic condition in cats. JAPANESE JOURNAL OF PHARMACOLOGY 1992; 59:435-41. [PMID: 1434139 DOI: 10.1254/jjp.59.435] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The spinal reflex potentials elicited by electrical stimulation of the tibial nerve were recorded from the lumbo-sacral ventral root in spinal cats. When the thoracic aorta and the bilateral internal mammary arteries were occluded for 10 min, the potentials were completely depressed. Reappearance of these potentials could be observed at about 10 min after removal of the occlusion and they gradually recovered. Intravenous injection of naloxone (1 or 10 mg/kg) or levallorphan (0.1 mg/kg) together with removal of occlusion significantly promoted the recovery of the polysynaptic reflex potential. Morphine (5 mg/kg) showed no particular effect on the recovery of potentials. Furthermore, pretreatment with morphine (5 mg/kg) did not influence the effects of these opioid antagonists. These results suggest that naloxone and levallorphan may preserve or potentiate the interneuronal activities of the lumbo-sacral spinal cord under the ischemic condition and that the effects may not be mediated through morphine-like opioid receptors.
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Affiliation(s)
- Y Okamoto
- Department of Pharmacology, School of Medicine, Chiba University, Japan
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88
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Izumi Y, Roussel S, Pinard E, Seylaz J. Reduction of infarct volume by magnesium after middle cerebral artery occlusion in rats. J Cereb Blood Flow Metab 1991; 11:1025-30. [PMID: 1939380 DOI: 10.1038/jcbfm.1991.170] [Citation(s) in RCA: 116] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of magnesium, an endogenous inhibitor of calcium entry into neurons, upon ischemic brain damage were investigated using a well-characterized model of focal cerebral ischemia in rats. Infarct volumes were determined by 2,3,5-triphenyltetrazolium chloride transcardiac perfusion 48 h after middle cerebral artery (MCA) occlusion. The area of ischemic damage was quantified by image analysis in coronal sections taken every 0.5 mm. MgCl2 (1 mmol/kg) was injected intraperitoneally just after MCA occlusion and again 1 h later. Posttreatment with MgCl2 (16 control and 16 treated rats) significantly reduced the cortical infarct volume. Compensation for the hyperglycemic effect of MgCl2 with insulin (17 rats) further reduced the infarct volume in the neocortex. No systemic effects of either treatment could account for the observed neuroprotection.
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Affiliation(s)
- Y Izumi
- Laboratoire de Recherches Cérébrovasculaires, CNRS UA 641, Université Paris VII, France
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89
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90
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Agee JM, Flanagan T, Blackbourne LH, Kron IL, Tribble CG. Reducing postischemic paraplegia using conjugated superoxide dismutase. Ann Thorac Surg 1991; 51:911-4; discussion 914-5. [PMID: 2039320 DOI: 10.1016/0003-4975(91)91004-f] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Paraplegia after thoracic aortic aneurysm repair has an incidence of 2.2% to 24%. Oxygen-derived free radicals after reperfusion of an ischemic spinal cord may be partly responsible for neuronal destruction. We studied the effects of polyethylene glycol-conjugated superoxide dismutase (PEG-SOD), a free radical scavenger, as a way of increasing spinal cord tolerance to ischemia. Thirty rabbits underwent 40 minutes of aortic occlusion (a known model of paraplegia). Ten of these animals received 25,000 U/kg of PEG-SOD 24 hours before aortic occlusion and two additional doses of 10,000 U/kg, one before and one subsequent to spinal ischemia. Ten animals received superoxide dismutase in the same dosages as those receiving PEG-SOD. Ten control animals received placebo. All animals were studied for 96 hours, at which time a final neurological examination was performed and the results were recorded. Of the 10 animals treated with PEG-SOD, 2 were completely paralyzed whereas 8 had less (7) or no (1) neurological impairment. Eight of the 10 control animals and 9 of the 10 animals receiving superoxide dismutase were completely paralyzed. None of the control animals or animals receiving superoxide dismutase had a normal neurological examination (p less than or equal to 0.05). Treatment with PEG-SOD before and during occlusion increased the rabbit spinal cord tolerance to a 40-minute ischemic insult. Scavenging free radicals may lessen experimental spinal cord injury.
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Affiliation(s)
- J M Agee
- Department of Surgery, University of Virginia Health Sciences Center, Charlottesville
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91
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Breckwoldt WL, Genco CM, Connolly RJ, Cleveland RJ, Diehl JT. Spinal cord protection during aortic occlusion: efficacy of intrathecal tetracaine. Ann Thorac Surg 1991; 51:959-63. [PMID: 2039327 DOI: 10.1016/0003-4975(91)91015-n] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Spinal cord ischemia and resultant paraplegia are devastating sequelae in up to 40% of patients undergoing repair of thoracoabdominal aneurysms. We investigated the effect of intrathecal tetracaine on the neurological sequelae of spinal cord ischemia and reperfusion with aortic occlusion. Cocaine-derived anesthetics (lidocaine and its analogues) have been shown to decrease neuronal cell metabolism and also have specific neuronal membrane stabilizing effects. New Zealand white rabbits were anesthetized and spinal cord ischemia was then induced by infrarenal aortic occlusion. Animals were divided into six treatment groups. Tetracaine (groups 2 and 4) or normal saline solution (group 5) was administered intrathecally before aortic cross-clamping. Groups 1 and 3 functioned as controls. Group 6 animals received intravenous thiopental. Rabbits were classified as either neurologically normal or injured (paralyzed or paretic). Among controls, 25 minutes of aortic occlusion produced varied neurological sequelae (group 1, 3/6 injured, 50%) whereas 30 minutes resulted in more consistent injury (group 3, 5/6 injured, 83%). All rabbits that received intrathecal saline solution were paralyzed (group 5, 4/4 injured, 100%). Animals treated with intrathecal tetracaine and aortic occlusion of 30 minutes (group 4) showed significantly better preservation of neurological function (6/7 normal, 86%) than controls and saline-treated animals (groups 3 and 5). All animals treated with intrathecal tetracaine and aortic occlusion for 25 minutes (group 2) showed no signs of injury (5/5 normal, 100%), but this was not significant versus controls (group 1). Intravenous thiopental (group 6, 5/5 injured, 100%) had no beneficial effect. Intrathecal tetracaine significantly and dramatically abrogated the neurological injury secondary to spinal cord ischemia and reperfusion after aortic occlusion at 30 minutes in the rabbit model.
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Affiliation(s)
- W L Breckwoldt
- Department of Cardiothoracic Surgery, Tufts University School of Medicine, Boston, Massachusetts
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92
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Affiliation(s)
- A M Lam
- Department of Anesthesia and Neurosurgery, University of Washington School of Medicine, Seattle
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93
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Moore WM, Hollier LH. The influence of severity of spinal cord ischemia in the etiology of delayed-onset paraplegia. Ann Surg 1991; 213:427-31; discussion 431-2. [PMID: 2025062 PMCID: PMC1358465 DOI: 10.1097/00000658-199105000-00007] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
To clarify the cause of delayed-onset paraplegia, the authors evaluated the neurologic outcome after temporary (10 to 30 minutes) spinal cord ischemia in the awake rabbit. Loss of motor function occurred in less than 2 minutes in all animals. Restoration of flow within 16 minutes always resulted in full return of function, whereas with occlusion times of greater than 27 minutes all animals remained paralyzed. After temporary occlusion of 20 to 21 minutes, however, 71% of animals returned to normal neurologic function but developed delayed-onset paraplegia 14 to 48 hours later. This appears to be a reliable method for the creation of a model of delayed-onset paraplegia in the awake animal, and will facilitate more detailed studies of the pathophysiology of ischemia-induced paraplegia.
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Affiliation(s)
- W M Moore
- Department of Surgery, Ochsner Clinic, New Orleans, Louisiana 70121
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94
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Marsala J, Sulla I, Santa M, Marsala M, Zacharias L, Radonak J. Mapping of the canine lumbosacral spinal cord neurons by Nauta method at the end of the early phase of paraplegia induced by ischemia and reperfusion. Neuroscience 1991; 45:479-94. [PMID: 1722292 DOI: 10.1016/0306-4522(91)90243-h] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The Nauta impregnation method was used to map the neuronal changes in the canine lumbosacral segments following ischemia and reperfusion. The early perikaryal changes ensuing during the first phase after 30 min of thoracic aorta cross-clamping alone or followed by 30 min of reperfusion were mapped. During the second phase (one to six postischemic reperfusion days) the dendritic, preterminal and synaptic degeneration developed. The influence of 30 min cross-clamping immediately followed by perfusion fixation is characterized by the occurrence of flocculent argyrophilic clusters in the cytoplasm of middle-sized and large neurons of L3-S1 segments. Declamping of the thoracic aorta followed by 30 min of reperfusion basically modifies the susceptibility of lumbosacral neurons to Nauta impregnation promoting somatic and dendritic argyrophilia mainly of small (less than 15 microns) neurons, localized mostly in the fifth, sixth and seventh layers, respectively. This early appearing somatic and dendritic argyrophilia is not abolished by a pretreatment of sections with acetone in which cholesterol and its esters are highly soluble, or chloroform-methanol which extracts total lipid. After 24 h of reperfusion the somatic and dendritic argyrophilia is lost but the first signs of drop-like degeneration are detected in all but three superficial dorsal horn layers. At the end of the third reperfusion day, an atypical form of bouton degeneration was found, consisting of massive occurrence of enlarged (greater than 4 microns) boutons encircled by a clear halo. Laminar distribution of enlarged degenerating boutons coincides with laminar quantitative distribution of small argyrophilic neurons detected 30 min after reperfusion. The basic orientation of the many terminal fibres attached to enlarged boutons suggests that they belong to the axons localized mainly in the lateral and anterior columns. Despite a dense argyrophilic network pervading the gray matter of lumbosacral segments only pale shadows of middle-sized and large neurons were found at the end of the sixth reperfusion day and neither somatic nor vessel wall argyrophilia could be detected. All animals surviving one, three and six days postoperatively suffered from fully developed paraplegia.
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Affiliation(s)
- J Marsala
- Institute of Neurobiology, Slovak Academy of Sciences, Srobarova
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95
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McIntosh TK, Vink R, Soares H, Hayes R, Simon R. Effect of noncompetitive blockade of N-methyl-D-aspartate receptors on the neurochemical sequelae of experimental brain injury. J Neurochem 1990; 55:1170-9. [PMID: 2168932 DOI: 10.1111/j.1471-4159.1990.tb03122.x] [Citation(s) in RCA: 147] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Pharmacological inhibition of excitatory neurotransmission attenuates cell death in models of global and focal ischemia and hypoglycemia, and improves neurological outcome after experimental spinal cord injury. The present study examined the effects of the noncompetitive N-methyl-D-aspartate receptor blocker MK-801 on neurochemical sequelae following experimental fluid-percussion brain injury in the rat. Fifteen minutes after fluid-percussion brain injury (2.8 atmospheres), animals received either MK-801 (1 mg/kg, i.v.) or saline. MK-801 treatment significantly attenuated the development of focal brain edema at the site of injury 48 h after brain injury, significantly reduced the increase in tissue sodium, and prevented the localized decline in total tissue magnesium that was observed in injured tissue of saline-treated animals. Using phosphorus nuclear magnetic resonance spectroscopy, we also observed that MK-801 treatment improved brain metabolic status and promoted a significant recovery of intracellular free magnesium concentrations that fell precipitously after brain injury. These results suggest that excitatory amino acid neurotransmitters may be involved in the pathophysiological sequelae of traumatic brain injury and that noncompetitive N-methyl-D-aspartate receptor antagonists may effectively attenuate some of the potentially deleterious neurochemical sequelae of brain injury.
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Affiliation(s)
- T K McIntosh
- Department of Surgery, University of Connecticut Health Center, Farmington 06032
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96
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97
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Kouchoukos NT, Wareing TH, Izumoto H, Klausing W, Abboud N. Elective hypothermic cardiopulmonary bypass and circulatory arrest for spinal cord protection during operations on the thoracoabdominal aorta. J Thorac Cardiovasc Surg 1990. [DOI: 10.1016/s0022-5223(19)36940-5] [Citation(s) in RCA: 119] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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98
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Giulian D, Robertson C. Inhibition of mononuclear phagocytes reduces ischemic injury in the spinal cord. Ann Neurol 1990; 27:33-42. [PMID: 2301926 DOI: 10.1002/ana.410270107] [Citation(s) in RCA: 316] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Transient ischemia to the lumbar and sacral sections of the spinal cord of rabbit leads to a deterioration in neurological function that usually worsens 24 to 48 hours after injury. This decline in movement of the hindlimbs develops simultaneously with the appearance of mononuclear phagocytes in the gray matter of injured neural tissue. Chloroquine and colchicine inhibit phagocytic and secretory functions in mononuclear phagocytes. When given up to 6 hours after an induced ischemic lesion in rabbit, this drug combination decreased the number of mononuclear phagocytes found within the gray matter of damaged spinal cord, improved the recovery of function of the hindlimbs and bladder, preserved spinal somatosensory evoked potentials, and promoted the survival of motor neurons. In contrast, the glucocorticoid dexamethasone, a weak inhibitor of mononuclear phagocytes in vivo, did not reduce the number of inflammatory cells in the spinal cord and did not improve motor and bladder functions. The suppression of mononuclear phagocytes soon after ischemic injury may offer a new approach in the treatment of vascular disease in the central nervous system.
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Affiliation(s)
- D Giulian
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030
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99
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Robertson CS, Goodman JC, Grossman RG, Priessman A. Reduction in spinal cord postischemic lactic acidosis and functional improvement with dichloroacetate. J Neurotrauma 1990; 7:1-12. [PMID: 2342114 DOI: 10.1089/neu.1990.7.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Pyruvate dehydrogenase complex (PDHC) is a major enzyme of glucose metabolism. Dichloroacetate (DCA) is a noncompetitive inhibitor of PDHC kinase, an enzyme that inactivates PDHC. We examined the effects of DCA on extracellular lactate and pyruvate concentration changes and spinal somatosensory evoked potentials (SSEP) in ischemic rabbit spinal cords. In the first group of 26 animals, the aorta was occluded until postsynaptic SSEP waves were completely suppressed for 10 min, a period of ischemia that causes neurologic deficits in 50% of untreated animals. DCA (25 mg/kg) was given to 13 of these animals before ischemia. In the second group of 24 animals, the aorta was occluded until the postsynaptic SSEP waves were absent for 20 min, a period of ischemia that produces paraplegia in 100% of untreated animals. DCA (25 mg/kg) was given to 16 of these animals just before the aortic occlusion was released. After occlusion, extracellular spinal lactate concentrations increased abruptly while pyruvate concentrations fell. Both lactate and pyruvate concentrations reached a plateau during the ischemic period but increased when the aortic balloon was deflated. DCA-treated animals had lower lactate and pyruvate peak concentrations during reperfusion, as well as more rapid and greater recovery of SSEP at 2 h after reperfusion. DCA did not alter spinal metabolism during the ischemia but appeared to produce a more rapid shift to glucose metabolism on reperfusion. Thus, DCA treatment resulted in better electrophysiological recovery after both moderate and severe ischemia, either by reducing lactic acidosis or by increasing the recovery rate of aerobic energy production.
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Affiliation(s)
- C S Robertson
- Department of Neurosurgery, Baylor College of Medicine, Houston, Texas
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100
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Marsala J, Sulla I, Santa M, Marsala M, Mechírová E, Jalc P. Early neurohistopathological changes of canine lumbosacral spinal cord segments in ischemia-reperfusion-induced paraplegia. Neurosci Lett 1989; 106:83-8. [PMID: 2586833 DOI: 10.1016/0304-3940(89)90206-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Mapping the canine lumbosacral spinal cord neurons damaged by ischemia-reperfusion after high thoracic aorta ligation was performed using the Nauta degenerating method. Highly Nauta-positive perikarya of the long ascending projection systems in the 4th to 6th dorsal layer, interneurons in the 7th layer and motoneurons in the 8th and 9th layers in L3-S3 segments subjected to 30 min of ischemia and 30 min of reperfusion were localized and their laminar distribution was specified. Spastic paraplegia fully developed 2 days postoperatively after 30 min of aortic ligation is neurohistopathologically characterized by occurrence of enlarged Nauta-positive boutons with prevailing localization in the 4th to 8th layer of the gray matter.
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Affiliation(s)
- J Marsala
- Institute of Neurobiology, Centre of Physiological Sciences, Slovak Academy of Sciences, Kosice, Czechoslovakia
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