NEUROPSYCHOLOGIC CHANGE AFTER CARDIAC-SURGERY - A CRITICAL-REVIEW

Studies that have examined neuropsychologic change after cardiac surge ry address three main issues: (1) the incidence of cognitive change; ( 2) the identification of factors that put patients at higher risk; and (3) the evaluation of interventions to prevent these complications. T his review attempts to bring together concerns associated with various study designs and to integrate the conclusions from these studies. Th irty five studies have been examined in this review. Some of the diffi culties encountered when quantifying the degree of cognitive change ar e related to study design, patient sampling, and deficit definition. A dditionally, changing patient populations have influenced results repo rted from different health care settings. Increasing age and longer ca rdiopulmonary bypass times have been correlated with cognitive decline in a number of studies. Filtration devices and blood gas management t echniques have decreased but not eliminated the number of patients who have cognitive decline. Cognitive change exists following cardiac pro cedures. Identification of a subgroup of patients at high risk for cog nitive change has been difficult, possibly due to issues of study desi gn. Design of future studies, which may include intraoperative or phar macologic interventions, is dependent on identification of this high-r isk group. Copyright (C) 1996 by W.B. Saunders Company.