Encephalopathy and stroke after coronary artery bypass grafting: incidence, consequences, and prediction.
BACKGROUND
In contrast to perioperative stroke, much less attention has been paid to those with evidence of diffuse brain encephalopathy, presenting as delirium, confusion, coma, and seizures in the immediate postoperative period.


OBJECTIVE
To determine the incidence, consequences, and predictive factors for encephalopathy and stroke following coronary artery bypass grafting.


METHODS
In a prospective evaluation of 2711 patients operated on between January 1, 1997, and December 31, 2000, preoperative risk factors were obtained before surgery and postoperative outcomes, encephalopathy and stroke, were determined on a daily basis. All strokes were confirmed by neurologic consultation and, in most instances, by imaging. Logistic regression analyses were performed to determine risk factors for these outcomes.


RESULTS
The incidence of encephalopathy was 6.9% and of stroke, 2.7%. For patients without either of these outcomes, the average length of stay in the hospital was 6.6 days and the mortality was 1.4%. In contrast, patients with encephalopathy had a length of stay of 15.2 days and a mortality of 7.5%, and those with stroke, a length of stay of 17.5 days and a mortality of 22.0%. Predictive models were developed for encephalopathy involving 5 preoperative factors (age, past stroke, carotid bruit, hypertension, and diabetes) and 1 perioperative factor (time on cardiopulmonary bypass). The model for stroke involved only 3 preoperative risk factors (past stroke, hypertension, and diabetes).


CONCLUSIONS
Encephalopathy or stroke is associated with significant increases in length of stay and mortality after coronary artery bypass grafting. Patients at higher risk for these outcomes can be identified before surgery.
McKhann
Guy M
GM
Zanvyl Krieger Mind/Brain Institute, The Johns Hopkins University, 338 Krieger Hall, 3400 N Charles St, Baltimore, MD 21218-2685, USA. Guy.Mckhann@jhu.edu
Grega
Maura A
MA
Borowicz
Louis M
LM
Bechamps
Michon
M
Selnes
Ola A
OA
Baumgartner
William A
WA
Royall
Richard M
RM
D000368:Aged; D000758:Anesthesia; D001927:Brain Diseases / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D002315:Cardiopulmonary Bypass / Q000009:adverse effects; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010477:Perfusion; D011183:Postoperative Complications / Q000453:epidemiology / Q000473:pathology*; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology