Effect of ischaemic preconditioning, cardiopulmonary bypass and myocardial ischaemic/reperfusion on free radical generation in CABG patients.
OBJECTIVE
To investigate the free radicals (FR) generation after ischaemic preconditioning and cardiopulmonary bypass and during reperfusion in CABG patients, and the role of ischaemic preconditioning.


METHODS
Forty-three CABG patients were randomised into an ischaemic preconditioning and a control group. The protocol for ischaemic preconditioning was two cycles of 2-min ischaemia followed by 3-min reperfusion. Free radicals were measured using electron spin resonance spectroscopy. Global and right heart functions were collected.


RESULTS
The free radicals generation in coronary sinus blood in the ischaemic preconditioning group was 9.7 and 16.6% after the ischaemic preconditioning protocol and 10 min after declamping, 6.8 and 13.3% in the controls. The free radicals in arterial samples were, respectively, 21, 14, 10 and 9% at 10 min, 1, 2 and 24 h after reperfusion. Cardiac index (CI) and right ventricular ejection fraction (RVEF) were improved by ischaemic preconditioning.


CONCLUSIONS
Both ischaemic preconditioning and cardiopulmonary bypass induced free radicals generation. Although ischaemic preconditioning had no effect on free radicals generation after the operation, it protected against postoperative stunning.
Wu
Z K
ZK
Division of Cardiac Surgery, Tampere University Hospital, P.O. Box 2000, 33521, Tampere, Finland.
Tarkka
M R
MR
Eloranta
J
J
Pehkonen
E
E
Laurikka
J
J
Kaukinen
L
L
Honkonen
E L
EL
Vuolle
M
M
Kaukinen
S
S
D000368:Aged; D002302:Cardiac Output / Q000502:physiology; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass; D005260:Female; D005609:Free Radicals / Q000097:blood*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D019157:Ischemic Preconditioning, Myocardial; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000503:physiopathology*; D017682:Myocardial Stunning / Q000503:physiopathology / Q000517:prevention & control; D011183:Postoperative Complications / Q000503:physiopathology*; D013318:Stroke Volume / Q000502:physiology; D016277:Ventricular Function, Left / Q000502:physiology
D005609:Free Radicals