Journal of neurosurgery
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Journal of neurosurgery · Oct 1996
Moderate hypothermia in patients with severe head injury: cerebral and extracerebral effects.
Cerebral and extracerebral effects of moderate hypothermia (core temperature 32.5 degrees C-33.0 degrees C) were prospectively studied in 10 patients with severe closed head injury (Glasgow Coma Scale score < 7) in the intensive care unit of a university hospital. Hypothermia was induced by cooling the patient's body surface with water-circulating blankets. Before cooling, a conventional intracranial pressure (ICP) reduction therapy was applied, which remained unchanged throughout the study. ⋯ Seven patients made a good recovery; one survived severely disabled; and two patients died. Moderate hypothermia is effective in preventing secondary brain damage while reducing cerebral ischemia. However, there are potentially hazardous side effects that require additional monitoring.
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Journal of neurosurgery · Oct 1996
Effect of the novel high-affinity glycine-site N-methyl-D-aspartate antagonist ACEA-1021 on 125I-MK-801 binding after subdural hematoma in the rat: an in vivo autoradiographic study.
Acute subdural hematoma (SDH) complicates 20% of severe human head injuries and causes death or severe disability in 60% of these cases, due to brain swelling and high intracranial pressure. Although the mechanisms for these phenomena are unknown, previous studies have implicated excitatory amino acid-mediated mechanisms in both humans and animal models. The authors therefore performed in vivo autoradiography using 125I-MK-801, a high-affinity noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, as a tracer to evaluate NMDA ion channel activation spatially and temporally as a factor causing cytotoxic swelling. ⋯ Pretreatment with ACEA-1021 reduced 125I-MK-801 uptake by 28% (3.41 +/- 0.26 nCi/mg vs. 4.73 +/- 0.36 nCi/mg; p < 0.05), indicating that this agent prevents opening of the NMDA ion channel and, thus, exposure of its receptor for MK-801 binding. These studies show intense foci of penumbral NMDA receptor-mediated ion channel activation after onset of SDH, which is markedly reduced by an NMDA antagonist. Such agents are thus likely to reduce cell swelling after SDH occurs.