Effects of hemodialysis on the cognitive and sensory-motor functioning of the adult chronic hemodialysis patient.

Twenty chronically dialyzed adults were administered a repeatable battery of 14 cognitive and sensory-motor tests on 3 consecutive days: immediately prior to their midweek dialysis, approximately 20 hr after their midweek dialysis, and again immediately prior to their end-of-the week dialysis. Serum electrolyte and methylamine analyses were performed at each test session. When compared to established norms, these patients scored within the normal range in a wide variety of areas. Limited impairments, probably due to peripheral neuropathy, were in evidence on the Grooved Pegboard, Finger Tapping (females), and Grip Strength (females) measures. Impairments suggestive of cerebral dysfunction were also noted on the Benton Visual Retention Test and on the Trail Making Test, Parts A and B, with particularly severe impairment noted on Part B. Despite significant daily changes in serum levels of toxic substances retained in uremia, there was little or no evidence to suggest that well-dialyzed patients undergo daily fluctuations in their cognitive and sensory-motor functioning.