Intra- and postoperative predictors of stroke after coronary artery bypass grafting.
BACKGROUND
Stroke is a devastating complication of coronary artery bypass graft surgery. An individual's risk of stroke is based in part on preoperative characteristics but also on intra- and postoperative factors. We developed a risk prediction model for stroke based on factors in intra- and postoperative care, after adjusting for a patient's preoperative risk.


METHODS
We conducted a regional prospective study of 11,825 consecutive patients undergoing coronary artery bypass graft surgery surgery from 1996 to 2001. Data were collected on patient and disease characteristics, intra- and postoperative care and course, and outcomes. Stroke was defined as "a new focal neurologic deficit which appears and is still at least partially evident more than 24 hours after its onset." Logistic regression identified significant predictors of stroke.


RESULTS
The incidence of stroke was 1.5%. The regression model significantly predicted the occurrence of stroke. As compared with cardiopulmonary bypass for less than 90 minutes, cardiopulmonary bypass for 90 to 113 minutes, odds ratio = 1.59, p = 0.022), cardiopulmonary bypass for 114 minutes or more (odds ratio = 2.36, p < 0.001), atrial fibrillation (odds ratio = 1.82, p < 0.001), and prolonged inotrope use (odds ratio = 2.59, p = 0.001) significantly improved our ability to predict stroke. Nearly 75% of all strokes occurred among the 90% of patients at low or medium preoperative risk.


CONCLUSIONS
The inclusion of factors associated with intra- and postoperative care and course significantly improved the prediction model. Most strokes occurred among patients at low or medium preoperative risk, suggesting that many of these strokes may be preventable. Reduction in stroke risk may require modifications in intra- and postoperative care and course.
Likosky
Donald S
DS
Department of Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03756, USA. donald.s.likosky@dartmouth.edu
Leavitt
Bruce J
BJ
Marrin
Charles A S
CA
Malenka
David J
DJ
Reeves
Alexander G
AG
Weintraub
Ronald M
RM
Caplan
Louis R
LR
Baribeau
Yvon R
YR
Charlesworth
David C
DC
Ross
Cathy S
CS
Braxton
John H
JH
Hernandez
Felix
F
O'Connor
Gerald T
GT
D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D016001:Confidence Intervals; D001026:Coronary Artery Bypass / Q000009:adverse effects* / Q000379:methods*; D003327:Coronary Disease / Q000401:mortality / Q000601:surgery; D005260:Female; D006801:Humans; D015994:Incidence; D007431:Intraoperative Complications / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009511:New England / Q000453:epidemiology; D016017:Odds Ratio; D011183:Postoperative Complications / Q000453:epidemiology*; D011237:Predictive Value of Tests; D011336:Probability; D011446:Prospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D020521:Stroke / Q000453:epidemiology*; D016019:Survival Analysis