Cerebrovascular response to intracranial hypertension.

摘要: Pial arterial and venous calibre changes during intracranial hypertension were studied in 11 cats under barbiturate- nitrous oxide-anaesthesia by using a closed cranial window technique multichannel videoangiometry. Intracranial pressure was elevated from normal mean level of 6.4 mm Hg cisternal infusion mock CSF steps to 20, 30, 40, 50 finally the systolic pressure. arteries dilated significantly, small ones more than large ones, 42 +/- 5.6% 33 3%, respectively at ICP 50. With further elevation up pressure, dilatation diminished 28 10% small, near resting calibres arteries. veins remained unreactive on average. Grouping into smaller larger 100 microns size revealed, however, minor though statistically significant 5-10% diminution veins. Blood flow stopped, when cerebral perfusion zero, neither nor collapsed. The present data support hypothesis that CBF acute depends rather local vascular compression.