Autoregulation of Cerebral Blood Flow in Hypertensive Patients
نویسنده
چکیده
Autoregulation of cerebral blood flow (CBF) was studied by the arteriovenous oxygen difference method in 13 patients with untreated or ineffectively treated severe hypertension, nine patients with effectively treated, formerly severe hypertension, and ten normotensive controls. Resting mean blood pressure in these three groups was 145 ± 17 (1 SD) mm Hg, 116 ± 18 mm Hg, and 98 ± 10 mm Hg, respectively. Blood pressure was decreased by trimethaphan infusion combined with head-up tilt. The lower limit of CBF autoregulation in the three groups was 113 ± 17 mm Hg, 96 ± 17 mm Hg, and 73 ± 9 mm Hg, and the lowest tolerated blood pressure
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