HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Lewis, M. S. Articles by Scott, D. A. Search for Related Content PubMed PubMed Citation Articles by Lewis, M. S. Articles by Scott, D. A. Related Collections Extracorporeal circulation

Ann Thorac Surg 2006;81:2097-2104
© 2006 The Society of Thoracic Surgeons

---

Original article: Cardiovascular

Detection of Postoperative Cognitive Decline After Coronary Artery Bypass Graft Surgery is Affected by the Number of Neuropsychological Tests in the Assessment Battery

^a Centre for Anaesthesia and Cognitive Function, Department of Anaesthesia, St. Vincent's Hospital, Victoria Parade, Melbourne
^b School of Psychological Science, La Trobe University, Victoria, Australia

Accepted for publication January 10, 2006.

^_* Address correspondence to Dr Lewis, Department of Anaesthesia, St. Vincent's Hospital, Victoria Parade, Melbourne 3065, Australia (Email: matt.lewis2{at}gmail.com).

BACKGROUND: The assessment of postoperative cognitive dysfunction after coronary artery bypass graft surgery is made with the repeated administration of cognitive tests. This classification is vulnerable to error, and it has been suggested that increasing the number of tests in a battery while maintaining constant inclusion criteria for postoperative cognitive dysfunction increases the rate of false positive classification of deterioration. The current study tested this by applying a constant rule for cognitive dysfunction using combinations of two to seven cognitive tests.

METHODS: Two hundred and four coronary artery bypass graft patients (surgical) and 90 healthy nonsurgical controls aged 55 years or older completed a battery of cognitive tests at baseline (preoperative) and 1 week later (postoperative). In both groups, postoperative cognitive dysfunction was classified using all unique combinations of two to seven cognitive tests when performance deteriorated on two or more tests by at least the value of the baseline standard deviation.

RESULTS: The average incidence of cognitive dysfunction progressively increased in both groups as the number of cognitive tests increased from two (surgical: 13.3%; control: 3.1%) to seven tests (surgical: 49.4%; control: 41.1%).

CONCLUSIONS: Increasing the number of tests used to classify postoperative cognitive dysfunction appears to increase the sensitivity to change in the coronary artery bypass graft group. However, accompanying false positive classifications suggest that this improved sensitivity reflected increased error. Future rules for postoperative cognitive dysfunction need to account for this error and include a control group.

This article has been cited by other articles:

				R. P. Alston, R. A. Kumar, C. Cann, J. Hall, P. Sudheer, and A. Wilkes IL-18 and SC5b-9 for predicting neurocognitive dysfunction after cardiopulmonary bypass Br. J. Anaesth., September 1, 2007; 99(3): 444 - 445. [Full Text] [PDF]

				C. W. Hogue, O. A. Selnes, and G. McKhann Should All Patients Undergoing Cardiac Surgery Have Preoperative Psychometric Testing: A Brain Stress Test? Anesth. Analg., May 1, 2007; 104(5): 1012 - 1014. [Full Text] [PDF]

				B. S. Silbert, D. A. Scott, L. A. Evered, M. S. Lewis, and P. T. Maruff Preexisting Cognitive Impairment in Patients Scheduled for Elective Coronary Artery Bypass Graft Surgery Anesth. Analg., May 1, 2007; 104(5): 1023 - 1028. [Abstract] [Full Text] [PDF]