Reduction of the inflammatory response following coronary bypass grafting with total minimal extracorporeal circulation.
OBJECTIVE
Cardiopulmonary bypass (CPB) is known to cause part of the systemic inflammatory reaction after cardiac surgery that can be responsible for organ failure. A novel technique based on a minimal extracorporeal circulation (MECC(R)) system has been evaluated with regard to the inflammatory response in a prospective study involving patients undergoing coronary artery bypass grafting.


METHODS
Sixty consecutive patients were randomly assigned to either standard normothermic CPB (n=30) or the MECC system, with a reduced priming volume, no aortic venting and no venous reservoir, excluding the blood-air interface (n=30). Specific evaluation of cytokine release (IL-1beta, IL-6, TNF-alpha), as well as neutrophil elastase secretion and beta-thromboglobulin release from platelets and S100 protein assay were performed. Serial blood samples were taken prior to the onset, after initiation, at the end and after weaning of the CPB; further samples were collected 6 and 24h after the end of the CPB.


RESULTS
All patients were similar with regards to pre- and intra-operative characteristics and clinical outcomes were comparable for both groups. MECC system allowed a reduced hemodilution with a mean drop of the hematocrit of 8.5 vs. 15.3% (P<0.05). Mononuclear phagocytes dropped in a more important manner under standard CPB conditions (247+/-151 vs. 419+/-168, P=0.002), but both groups demonstrated a rise in monocyte count at the end of the CBP. No significant release of IL-1beta was observed in either group. By the end of CPB, IL-6 levels were significantly lower in the MECC group (38.8+/-19.6 vs. 87.9+/-78.9, P=0.04), despite a higher monocyte count. Plasma levels of TNF-alpha rised significantly more during standard CPB than with the MECC system (17.8+/-15.4 vs. 10.1+/-5.6, P=0.002). With MECC, the neutrophil elastase release was reduced (72.7+/-47.9 vs. 219.6+/-103.4, P=0.001). Platelet count remained at higher values with the minimal compared to standard CPB. It is noteworthy to consider that beta-thromboglobulin levels showed slightly lower platelet activation in the MECC group at all times of CPB (110.5+/-55.6 vs. 134.7+/-46.8, P=0.10). The pattern of release of S100 protein showed higher values in patients undergoing standard CPB than after MECC.


CONCLUSIONS
The MECC system is suitable to maintain total extracorporeal circulation and demonstrates a lower inflammatory reaction when compared to standard CPB.
Fromes
Yves
Y
Department of Cardiac Surgery, Fondation Hôpital Saint Joseph, 185 rue Raymond Losserand, Paris, France. y.fromes@myologie.chups.jussieu.fr
Gaillard
Didier
D
Ponzio
Olivier
O
Chauffert
Maryline
M
Gerhardt
Marie-Françoise
MF
Deleuze
Philippe
P
Bical
Olivier M
OM
D000368:Aged; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000097:blood* / Q000601:surgery*; D004311:Double-Blind Method; D015199:Extracorporeal Membrane Oxygenation / Q000379:methods*; D006801:Humans; D007375:Interleukin-1 / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D007958:Leukocyte Count; D019272:Leukocyte Elastase / Q000097:blood; D008875:Middle Aged; D015539:Platelet Activation; D010976:Platelet Count; D011446:Prospective Studies; D018709:Statistics, Nonparametric; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis; D001620:beta-Thromboglobulin
D007375:Interleukin-1; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D001620:beta-Thromboglobulin; D019272:Leukocyte Elastase