Heparin-bonded cardiopulmonary bypass circuits reduce cognitive dysfunction.
OBJECTIVE
To determine the incidence of cerebral dysfunction in cardiac surgical patients exposed to heparin-bonded cardiopulmonary bypass (HB-CPB) versus nonheparin-bonded cardiopulmonary bypass (NH-CPB) circuits through neuropsychometric testing and to correlate these findings with markers of the systemic inflammatory response to CPB.


METHODS
Prospective, randomized, blinded clinical trial.


METHODS
University hospital.


METHODS
Sixty-one patients undergoing elective cardiac surgery.


METHODS
A cohort of 61 patients scheduled for elective coronary artery bypass graft surgery were prospectively randomized to receive either HB-CPB or NH-CPB circuits during surgery. Patients were evaluated for cerebral injury using a battery of neuropsychometric tests at the following 3 time points: (1) before surgery as a baseline examination, (2) postoperative day 5, and (3) postoperative week 6. Blood samples were drawn to measure inflammatory markers at the following time points: (1) preincision, after induction of anesthesia, (2) 15 minutes after onset of CPB, (3) 30 minutes after CPB, (4) 6 hours postoperatively, and (5) 24 hours postoperatively.


RESULTS
Neuropsychometric performance was evaluated by group-rate and event-rate analyses. By group-rate analysis, patients undergoing surgery with HB-CPB performed significantly better at 5 days after surgery on 2 neuropsychometric tests (trails A [p < 0.01] and finger tapping with the dominant hand [p < 0.01]) and at 6 weeks after surgery on one neuropsychometric test (trails A [p < 0.01]). By event-rate analysis, at 5 days, patients undergoing surgery with HB-CPB circuits had less cognitive dysfunction (p < 0.05) compared with patients undergoing surgery with NH-CPB circuits. Serum samples were analyzed to evaluate markers of complement activation (C3a), proinflammatory cytokines (tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-6), and coagulation (thrombin-antithrombin complex [TAT]) using the quantitative sandwich enzyme immunoassay technique. Although there were no significant differences in cytokine activation in either group, C3a was significantly higher in the NH-CPB group intraoperatively at 1 hour after CPB (p < 0.05), and TAT was higher in the HB-CPB group at 24 hours after surgery (p < 0.05).


CONCLUSIONS
Patients undergoing cardiac surgery with CPB have less postoperative cognitive dysfunction during CPB when HB-CPB circuits are employed. Although there was a relationship, this finding did not correlate with decreased complement activation intraoperatively and activation of coagulation postoperatively.
Heyer
Eric J
EJ
Departments of Anesthesiology, Surgery, and Neurology, College of Physicians and Surgeons of Columbia University, and Columbia--Presbyterian Medical Center, New York, NY 10032, USA. ejh3@columbia.edu
Lee
Kevin S
KS
Manspeizer
Heather E
HE
Mongero
Linda
L
Spanier
Talia B
TB
Caliste
Xzabia
X
Esrig
Barry
B
Smith
Craig
C
D000990:Antithrombin III / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000295:instrumentation; D020099:Coated Materials, Biocompatible; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control; D001026:Coronary Artery Bypass; D004311:Double-Blind Method; D005260:Female; D006493:Heparin; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010447:Peptide Hydrolases / Q000032:analysis; D011446:Prospective Studies; D018746:Systemic Inflammatory Response Syndrome / Q000175:diagnosis / Q000209:etiology
D015415:Biomarkers; D020099:Coated Materials, Biocompatible; D018836:Inflammation Mediators; C046193:antithrombin III-protease complex; D000990:Antithrombin III; D006493:Heparin; D010447:Peptide Hydrolases