Epiaortic scanning modifies planned intraoperative surgical management but not cerebral embolic load during coronary artery bypass surgery.
BACKGROUND
Patients with aortic atheroma are at increased risk for neurological injury after coronary artery bypass graft (CABG) surgery. We sought to determine the role of epiaortic ultrasound scanning for reducing cerebral embolic load, and whether its use leads to changes of planned intraoperative surgical management in patients undergoing CABG surgery.


METHODS
Patients >70-yr-of-age scheduled for CABG surgery were prospectively randomized to either an epiaortic scanning (EAS) group (aortic manipulation guided by epiaortic ultrasound) or a control group (manual aortic palpation without EAS). All patients received a comprehensive transesophageal echocardiographic examination. Transcranial Doppler (TCD) was used to monitor the middle cerebral arteries for emboli continuously from 2 min before aortic cannulation to 2 min after aortic decannulation. Neurological assessment was performed with the National Institute of Health stroke scale before surgery and at hospital discharge. The NEECHAM confusion scale was used for assessment and monitoring of patient global cognitive function on each day after surgery until hospital discharge.


RESULTS
Intraoperative surgical management was changed in 16 of 55 (29%) patients in the EAS group and in 7 of 58 (12%) patients in the control group (P = 0.025). These changes included adjustments of the ascending aorta cannulation site for cardiopulmonary bypass (CPB), the avoidance of aortic cross-clamping by using ventricular fibrillatory arrest during surgery, or by conversion to off-pump surgery. During surgery, 7 of 58 (12%) patients in the control group crossed over to the EAS group based on the results of manual aortic palpation. The median [range] TCD detected cerebral embolic count did not differ between the EAS and control groups during aortic manipulations (EAS, 11.5 [1-516] vs control, 22.0 [1-160], P = 0.91) or during CPB (EAS, 42.0 [4-516] vs control, 63.0 [5-758], P = 0.46). The NEECHAM confusion scores and National Institute of Health stroke scale scores were similar between the two groups.


CONCLUSIONS
These results show that the use of EAS led to modifications in intraoperative surgical management in almost one-third of patients undergoing CABG surgery. The use of EAS did not lead to a reduced number of TCD-detected cerebral emboli before or during CPB.
Djaiani
George
G
Department of Anesthesiology, Toronto General Hospital, Eaton North 3-410, 200 Elizabeth Street, Toronto, ON M5G 2C4, Canada. george.djaiani@uhn.on.ca
Ali
Mohamed
M
Borger
Michael A
MA
Woo
Anna
A
Carroll
Jo
J
Feindel
Christopher
C
Fedorko
Ludwik
L
Karski
Jacek
J
Rakowski
Harry
H
D000368:Aged; D001011:Aorta / Q000000981:diagnostic imaging*; D001018:Aortic Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D050197:Atherosclerosis / Q000150:complications / Q000000981:diagnostic imaging*; D002315:Cardiopulmonary Bypass; D002985:Clinical Protocols; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D003324:Coronary Artery Disease / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D017548:Echocardiography, Transesophageal; D005260:Female; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000209:etiology*; D007430:Intraoperative Care / Q000379:methods*; D008297:Male; D010173:Palpation; D018579:Patient Selection; D011446:Prospective Studies; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome; D017585:Ultrasonography, Doppler, Transcranial; D018084:Ultrasonography, Interventional