Lippincott, Williams & Wilkins
Journal of the American Society of Nephrology (JASN)
Original Item ID
Patients with ESKD have a high burden of ischemic brain lesions related to decline in cerebral blood flow during hemodialysis. Preliminary studies in patients on hemodialysis noted impairment in cerebrovascular reactivity, a mechanism that regulates cerebral perfusion. We found that lower cerebrovascular reactivity was associated with greater decrease in cerebral oxygen saturation during hemodialysis, particularly when accounting for changes in systemic BP. These results suggest that testing cerebrovascular reactivity could be relevant to characterizing risk of cerebral ischemia during hemodialysis and the potential sequelae of brain injury and cognitive impairment over time.
Patients with kidney failure treated with hemodialysis (HD) may be at risk for cerebral hypoperfusion due to HD-induced BP decline in the setting of impaired cerebral autoregulation. Cerebrovascular reactivity (CVR), the cerebrovascular response to vasoactive stimuli, may be a useful indicator of cerebral autoregulation in the HD population and identify those at risk for cerebral hypoperfusion. We hypothesize that CVR combined with intradialytic BP changes will be associated with declines in cerebral oxygenation saturation (ScO2) during HD.
Participants completed the MRI scans on a non-HD day and cerebral oximetry during HD. We measured CVR with resting-state fMRI (rs-fMRI) without a gas challenge and ScO2 saturation with near-infrared spectroscopy. Regression analysis was used to examine the relationship between intradialytic cerebral oxygen desaturation, intradialytic BP, and CVR in different gray matter regions.
Twenty-six patients on HD had complete data for analysis. Sixteen patients were men, 18 had diabetes, and 20 had hypertension. Mean±SD age was 65.3±7.2 years, and mean±SD duration on HD was 11.5±9.4 months. CVR in the anterior cingulate gyrus (ACG; P=0.03, r2=0.19) and insular cortex (IC; P=0.03, r2=0.19) regions negatively correlated with decline in intradialytic ScO2. Model prediction of intradialytic ScO2 improved when including intradialytic BP change and ultrafiltration rate to the ACG rsCVR (Pr2=0.48) and IC rsCVR (P=0.02, r2=0.35) models, respectively.
We found significant relationships between regional rsCVR measured in the brain and decline in intradialytic ScO2. Our results warrant further exploration of using CVR in determining a patient’s risk of cerebral ischemic injury during HD.
Richerson, W. T.; Schmit, Brian D.; and Wolfgram, D. F., "The Relationship between Cerebrovascular Reactivity and Cerebral Oxygenation during Hemodialysis" (2022). Biomedical Engineering Faculty Research and Publications. 675.
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