Cerebral Blood Flow Significantly Reduced After Hemodialysis
Conventional hemodialysis induces a reduction in cerebral blood flow in older patients.
HealthDay News — In elderly patients, conventional hemodialysis induces a reduction in cerebral blood flow (CBF), according to a study published online in the Journal of the American Society of Nephrology.
Harmke A. Polinder-Bos, MD, from the University of Groningen in the Netherlands, and colleagues examined the acute effect of conventional hemodialysis on CBF. Three [15O]H2O positron emission tomography-computed tomography scans were performed before, early after the start of, and at the end of hemodialysis. Global and regional changes in CBF were measured in 12 patients aged ≥65 years with a median dialysis vintage of 46 months.
The researchers observed a decrease in mean arterial blood pressure from 101 ± 11 mm Hg before hemodialysis to 93 ± 17 mm Hg at the end of hemodialysis. Global CBF decreased significantly by 10 ± 15%, from a mean of 34.5 to 30.5ml/100 g per minute from before the start to the end of hemodialysis. In one patient the decline in CBF (20%) was symptomatic. In all volumes of interest there were declines in regional CBF, including the frontal, parietal, temporal, and occipital lobes, the cerebellum, and thalamus. There was a correlation for higher tympanic temperature, ultrafiltration volume, ultrafiltration rate, and pH with lower CBF.
"Conventional hemodialysis induces a significant reduction in global and regional CBF in elderly patients," the authors write. "Repetitive intradialytic decreases in CBF may be one mechanism by which hemodialysis induces cerebral ischemic injury."
Polinder-Bos HA, Garcia DV, Kuipers J, et al. Hemodialysis induces an acute decline in cerebral blood flow in elderly patients [published online March 1, 2018]. J Am Soc Nephrol. doi:10.1681/ASN.2017101088