Retrograde cerebral perfusion during thoracic aortic surgery and late neuropsychological dysfunction

Objective: Retrograde cerebral perfusion (RCP) is commonly used in thoracic aortic surgery, ostensibly to provide metabolic support, maintain cerebral hypothermia and/or wash out particulate emboli. We tested the hypothesis t hat RCP would affect neuropsychological outcome in a clinical cohort. Metho ds: Ninety-four patients undergoing elective thoracic aortic repairs requir ing deep hypothermic circulatory arrest consented to participate in this st udy. These patients underwent preoperative neuropsychological evaluation an d comprise the reference group. Fifty-six of these patients also underwent neuropsychological evaluation several weeks postoperatively, 12 of whom (21 %) had RCP. The neuropsychological domains tested were attention, processin g speed, memory, executive function, and fine motor function. A global asse ssment of impairment, negative neuropsychological outcome (NNO), was define d as a postoperative decrease in function in two or more neuropsychological domains for patients with at least three domains tested both pre- and post operatively (n = 48). The relationship of three potential predictors (RCP, cerebral ischemia time and patient age) to negative outcomes was analyzed u sing Wilcoxon two-sample tests, chi (2) tests, Mantel-Haenszel tests and mu ltiple logistic regression. P < 0.05 was considered significant. Results: M emory dysfunction and NNO had strong associations with RCP. This effect rem ained significant when controlling separately for age and cerebral ischemia time. Conclusions: The effects of RCP are difficult to distinguish from th ose of age and prolonged cerebral ischemia time, because complex thoracic a ortic repairs are associated with advanced age, prolonged cerebral ischemia and use of RCP, Despite this limitation, these preliminary data indicated that RCP had no beneficial effect (and most likely a negative effect) upon cognitive outcome. (C) 2001 Elsevier Science B.V. All rights reserved.