Biomaterial Database

Optimal timing of hemodilution for brain protection in a canine model of focal cerebral ischemia. 1996

K Yanaka, and P J Camarata, and S R Spellman, and D E McDonald, and R C Heros

Department of Neurosurgery, University of Minnesota Medical School, Minneapolis 55455, USA.

OBJECTIVE Hemodilution is known to ameliorate the effects of focal ischemia when used shortly after cerebral arterial occlusion; however, it remains to be proved whether hemodilution will be effective when used at more clinically relevant times, ie, with some delay between the onset of ischemia and initiation of therapy. METHODS Thirty-two dogs were selected for inclusion in this study. Cerebral infarction was induced by permanent occlusion of the middle cerebral and the azygos anterior cerebral arteries. The animals were allocated to 1 of 4 groups of eight animals each: arterial occlusion without hemodilution (group 1); hemodilution immediately after occlusion (group 2); hemodilution 3 hours after occlusion (group 3); and hemodilution 6 hours after occlusion (group 4). Isovolemic hemodilution to a hematocrit of 30% was performed. The animals were killed 6 days after induction of ischemia, and the infarct size was determined. RESULTS Groups 2 and 3 showed significant reduction of infarct size (P < .0001) when compared with group 1. The neurological grade of group 3 on postoperative days 4, 5, and 6 was significantly better than those of groups 1 and 4 (P < .01). Group 4 showed a significant increase in the incidence of hemorrhagic infarction when compared with groups 1 and 2 (P < .01). CONCLUSIONS The current study indicates that hemodilution administered as much as 3 hours after ischemia is effective in reducing infarct size and improving neurological status. When administered 6 hours after ischemia, hemodilution is not helpful and may be harmful.

UI	MeSH Term	Description	Entries
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D001831	Body Temperature	The measure of the level of heat of a human or animal.	Organ Temperature,Body Temperatures,Organ Temperatures,Temperature, Body,Temperature, Organ,Temperatures, Body,Temperatures, Organ
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D002544	Cerebral Infarction	The formation of an area of NECROSIS in the CEREBRUM caused by an insufficiency of arterial or venous blood flow. Infarcts of the cerebrum are generally classified by hemisphere (i.e., left vs. right), lobe (e.g., frontal lobe infarction), arterial distribution (e.g., INFARCTION, ANTERIOR CEREBRAL ARTERY), and etiology (e.g., embolic infarction).	Anterior Choroidal Artery Infarction,Cerebral Infarct,Infarction, Cerebral,Posterior Choroidal Artery Infarction,Subcortical Infarction,Cerebral Infarction, Left Hemisphere,Cerebral Infarction, Right Hemisphere,Cerebral, Left Hemisphere, Infarction,Cerebral, Right Hemisphere, Infarction,Infarction, Cerebral, Left Hemisphere,Infarction, Cerebral, Right Hemisphere,Infarction, Left Hemisphere, Cerebral,Infarction, Right Hemisphere, Cerebral,Left Hemisphere, Cerebral Infarction,Left Hemisphere, Infarction, Cerebral,Right Hemisphere, Cerebral Infarction,Right Hemisphere, Infarction, Cerebral,Cerebral Infarctions,Cerebral Infarcts,Infarct, Cerebral,Infarction, Subcortical,Infarctions, Cerebral,Infarctions, Subcortical,Infarcts, Cerebral,Subcortical Infarctions
D002546	Ischemic Attack, Transient	Brief reversible episodes of focal, nonconvulsive ischemic dysfunction of the brain having a duration of less than 24 hours, and usually less than one hour, caused by transient thrombotic or embolic blood vessel occlusion or stenosis. Events may be classified by arterial distribution, temporal pattern, or etiology (e.g., embolic vs. thrombotic). (From Adams et al., Principles of Neurology, 6th ed, pp814-6)	Brain Stem Ischemia, Transient,Cerebral Ischemia, Transient,Crescendo Transient Ischemic Attacks,Transient Ischemic Attack,Anterior Circulation Transient Ischemic Attack,Brain Stem Transient Ischemic Attack,Brain TIA,Brainstem Ischemia, Transient,Brainstem Transient Ischemic Attack,Carotid Circulation Transient Ischemic Attack,Posterior Circulation Transient Ischemic Attack,TIA (Transient Ischemic Attack),Transient Ischemic Attack, Anterior Circulation,Transient Ischemic Attack, Brain Stem,Transient Ischemic Attack, Brainstem,Transient Ischemic Attack, Carotid Circulation,Transient Ischemic Attack, Posterior Circulation,Transient Ischemic Attack, Vertebrobasilar Circulation,Transient Ischemic Attacks, Crescendo,Vertebrobasilar Circulation Transient Ischemic Attack,Attack, Transient Ischemic,Attacks, Transient Ischemic,Brainstem Ischemias, Transient,Cerebral Ischemias, Transient,Ischemia, Transient Brainstem,Ischemia, Transient Cerebral,Ischemias, Transient Brainstem,Ischemias, Transient Cerebral,Ischemic Attacks, Transient,TIA, Brain,TIAs (Transient Ischemic Attack),Transient Brainstem Ischemia,Transient Cerebral Ischemia,Transient Cerebral Ischemias,Transient Ischemic Attacks
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D005073	Evoked Potentials, Somatosensory	The electric response evoked in the CEREBRAL CORTEX by stimulation along AFFERENT PATHWAYS from PERIPHERAL NERVES to CEREBRUM.	Somatosensory Evoked Potentials,Evoked Potential, Somatosensory,Somatosensory Evoked Potential
D006400	Hematocrit	The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.	Erythrocyte Volume, Packed,Packed Red-Cell Volume,Erythrocyte Volumes, Packed,Hematocrits,Packed Erythrocyte Volume,Packed Erythrocyte Volumes,Packed Red Cell Volume,Packed Red-Cell Volumes,Red-Cell Volume, Packed,Red-Cell Volumes, Packed,Volume, Packed Erythrocyte,Volume, Packed Red-Cell,Volumes, Packed Erythrocyte,Volumes, Packed Red-Cell
D006438	Hemodilution	Reduction of blood viscosity usually by the addition of cell free solutions. Used clinically (1) in states of impaired microcirculation, (2) for replacement of intraoperative blood loss without homologous blood transfusion, and (3) in cardiopulmonary bypass and hypothermia.	Hemodilutions
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia