Document Detail

Intrathecal magnesium sulfate protects the spinal cord from ischemic injury during thoracic aortic cross-clamping.
MedLine Citation:
PMID:  7992919     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Paraplegia is a known complication after surgery on the descending thoracic aorta. Thoracic aortic cross-clamping causes an increase in proximal aortic and cerebrospinal fluid pressures. Sodium nitroprusside, though effectively decreasing proximal aortic pressure, has been implicated in worsening the incidence of paraplegia by further increasing cerebrospinal fluid pressure and decreasing distal blood pressure, thereby reducing spinal cord perfusion pressure. Intravenous administration of magnesium sulfate has been shown to offer some spinal cord protection when used with mild hypothermia. This study investigated the effect of intrathecal magnesium on the prevention of paraplegia when sodium nitroprusside is used to control proximal hypertension during thoracic aortic cross-clamping in a dog model of spinal cord ischemia. METHODS: Two groups of eight dogs underwent thoracic aortic cross-clamping via a small thoracotomy incision for 45 min. Proximal, distal, and central venous pressures and cerebrospinal fluid pressures were monitored. Temperature was maintained at 36 degrees C. Sodium nitroprusside was used to control proximal hypertension. The control group received no magnesium sulfate, and a second group received 3 mg/kg intrathecal magnesium sulfate before thoracic aortic cross-clamping. The dogs were neurologically evaluated 24 h later by an observer blinded to the dogs' group. Spinal cord segments were obtained for histologic examination. RESULTS: Proximal mean arterial pressure, cerebrospinal fluid pressure, spinal cord perfusion pressure, and central venous pressure were not statistically different between the two groups. Neurologic outcome, however, was statistically different between the groups. None of the eight dogs in the magnesium group had any measurable neurologic injury, in contrast to the control group, in which seven of the eight dogs had severe neurologic injury (P < 0.005). Post mortem histologic data supported these findings. CONCLUSIONS: Intrathecal magnesium can prevent spinal cord injury despite markedly negative spinal cord perfusion pressure during thoracic aortic cross-clamping in a canine model of spinal cord ischemia.
J I Simpson; T R Eide; G A Schiff; J F Clagnaz; I Hossain; A Tverskoy; G Koski
Related Documents :
758389 - Assessment of patent ductus arteriosus shunting using diastolic pressure analysis.
7315549 - Simultaneous cerebral and spinal fluid pressure recordings. i. technique, physiology, a...
18234229 - Intracranial pressure and ventricular expansion in hydrocephalus: have we been asking t...
12324729 - Potential neuroprotective benefits of erythropoietin during experimental hypothermic ci...
2811409 - Glenn shunt: effect on pleural drainage after modified fontan operation.
12010739 - Blocking cerebrospinal fluid absorption through the cribriform plate increases resting ...
10393509 - Evidence for structural alterations in resistance arteries of patients with severe cong...
7125349 - Comparison of intraesophageal balloon pressure measurements with a nasogastric-esophage...
8964109 - Physiological and biochemical evidence for coordinate increases in muscarinic receptors...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Anesthesiology     Volume:  81     ISSN:  0003-3022     ISO Abbreviation:  Anesthesiology     Publication Date:  1994 Dec 
Date Detail:
Created Date:  1995-01-10     Completed Date:  1995-01-10     Revised Date:  2003-11-14    
Medline Journal Info:
Nlm Unique ID:  1300217     Medline TA:  Anesthesiology     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1493-9; discussion 26A-27A     Citation Subset:  AIM; IM    
Department of Anesthesiology, Long Island Jewish Medical Center, New Hyde Park, New York 11402.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Hypertension / prevention & control
Injections, Spinal
Ischemia / prevention & control*
Magnesium Sulfate / administration & dosage,  therapeutic use*
Models, Biological
Nitroprusside / therapeutic use
Paraplegia / etiology,  prevention & control*
Spinal Cord / blood supply*,  pathology
Thoracic Arteries / surgery*
Reg. No./Substance:
15078-28-1/Nitroprusside; 7487-88-9/Magnesium Sulfate

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Anesthetic depression of spinal motor neurons may contribute to lack of movement in response to noxi...
Next Document:  Does the brain influence somatic responses to noxious stimuli during isoflurane anesthesia?