Paper
Saturday, July 16, 2005
Neurocognitive Outcomes of Patients Following Off-Pump Coronary Artery Bypass Surgery
Sue Sendelbach, RN, PhD, CCNS, FAHA1, Shigeaki Watanuki, RN, PhD2, Kristin E. Sandau, RN, PhD1, Ruth Ann Lindquist, RN, PhD, APRN, BC, FAAN3, and Kay Savik, MS3. (1) Abbott Northwestern Hospital, Minneapolis, MN, USA, (2) School of Nursing and Rehabilitations, Aino University, Osaka, Japan, (3) School of Nursing, University of Minnesota, Minneapolis, MN, USA
Despite substantial reductions in age- and risk-adjusted mortality after coronary artery bypass graft (CABG) surgery over the decades, the reported prevalence of neuropsychological functional decline in patients after CABG has changed little, ranging from 31% to 73%. Use of the cardiopulmonary bypass pump (CPB) is a possible contributor to this decline. “Off-pump” CABG (OPCAB) surgery without CPB has become an alternative but studies of neuropsychological outcomes of OPCAB and correlates of outcome are few. Fifty-four patients at a Midwestern urban tertiary care center participated in the study. Neurocognitive tests of cognitive and motor functioning were administered within 72 hours preoperatively and between 72 hours and discharge postoperatively. Perioperative data were also collected to identify correlates of neuropsychological outcome. From the preoperative baseline to the postoperative follow-up before discharge, an improvement from preoperative cognitive composite of neurocognitive function was observed in contrast with most previously reported data. A decline in the motor composite of neurocognitive function was observed, congruent with results of previously reported studies. The improved cognitive composite may be attributed to the time of measurement, definition of decline, and statistical analyses employed. The cognitive composite outcomes correlated with the preoperative cognitive composite (p < .001), age (p = .01), and atrial fibrillation (p = .02), explaining 76.3% of the variance of the outcome. Outcome in the motor composite was correlated with preoperative motor composite score (p < .001), age (p = .04), and postoperative anxiety (p = .02); these variances explained 57.6% of the variance in the motor composite outcome. It is recommended that the study be replicated with a larger sample and design including a comparison group. Further studies to determine the relationships between neuropsychological outcomes at discharge and long-term follow-up and the implications of the results for real-world daily function are also recommended.