Regulation of cerebral blood flow in patients with autonomic dysfunction and severe postural hypotension.

摘要: Background: Whether cerebral blood flow (CBF) autoregulation is maintained in autonomic dysfunction has been debated for a long time, and the rather sparse data available are equivocal. The relationship between CBF mean arterial pressure (MABP) was therefore tested eight patients with symptoms signs of severe cardiovascular dysfunction. Patients methods: Eight were included, three whom had Parkinson's disease, diabetes, one pure failure last multiple system atrophy. By use two techniques, arteriovenous oxygen [(a-v)O2] method xenon-inhalation single photon emission tomography, 15 measurements (range 10–20) to four measurements, respectively, obtained each patient. Following during baseline, MABP raised gradually using intravenous noradrenaline infusion, then lowered by application lower body negative pressure. From (a-v)O2 samples response changes evaluated computer program fitting or regression lines through plot. Results conclusion: Preserved observed patients, while remaining five showed linear MABP. Comparison results tomographic demonstrated that it not possible assess whether autoregulated only pairs data.