Neurological research
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Although there has been renewed interest in human brain temperature, very little information is available on the association between brain temperature and cerebral perfusion pressure. In this study, we measured brain, tympanic, and rectal temperatures, arterial blood pressure and intracranial pressure in a case of massive hemorrhage deteriorating to brain death, and showed for the first time that when cerebral perfusion pressure began to decrease markedly brain temperature fell rapidly. Rectal and tympanic temperatures were higher than brain temperatures during the period of very low cerebral perfusion pressure. Circadian change in temperature (high at day, low at night) was preserved during the period of brain death.
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Neurological research · Dec 1995
Early hemodynamic changes at the microcirculatory level and effects of mannitol following focal cryogenic injury.
Changes in cerebral blood flow due to infusion of hyperosmolar solutions are of considerable importance in states of raised intracranial pressure. The present study was aimed to evaluate the effects of mannitol on the cerebral microcirculation, in a model of vasogenic brain edema. A right fronto-parietal craniotomy was performed in 30 adult Sprague-Dawley rats. ⋯ There was not significant difference between groups 2 and 3; however, there was a significant difference between mannitol and control groups after 15 min. During the early phase of vasogenic edema, early use of mannitol did not increase the blood flow, but stabilized it, preventing further decrease. Laser-Doppler flowmetry is a valuable method for continuous estimation of hemodynamic changes in the cerebral microcirculation.