RETRACTED: Hypothermic versus normothermic cardiopulmonary bypass: influence on circulating adhesion molecules

Cardiopulmonary bypass (CPB) may result in a whole-body inflammatory response with the risk of subsequent development of organ failure. Leukocyte-endothelial binding followed by neutrophil migration appear to play a central role. This process is markedly influenced by adhesion molecules. Whether plasma levels of circulating adhesion molecules are beneficially influenced by hypothermic CPB was studied in patients undergoing either hypothermic or normothermic CPB.

Prospective, randomized study.

Single-Institutional, clinical investigation in a cardiac anesthesia department of a university hospital.

30 patients scheduled for elective aortocoronary artery bypass grafting.

The patients were prospectively and randomly divided into two groups: group 1 underwent hypothermic CPB (rectal temperature 27 to 28 degrees C; n = 15) and group 2 normothermic CPB (rectal temperature > 36 degrees C; n = 15).

Plasma levels of circulating (soluble) adhesion molecules (endothelial leukocyte adhesion molecules [sELAM-1], vascular cell adhesion molecule-1 [sVCAM-1], intercellular adhesion molecule-1 [sICAM-1], and granule membrane protein 140 [sGMP-140]) were measured from arterial blood samples using enzyme-linked immunosorbent assays (ELISA) after induction of anesthesia (= baseline values), after weaning from bypass, at the end of surgery, 5 hours after the end of CPB, and on the morning of the first postoperative day. Mean rectal temperature of group 1 was 27.2 +/- 0.4 degrees C and 36.7 +/- 0.4 degrees C in group 2. In both groups, plasma levels of sELAM-1 were significantly higher than baseline only 5 hours after CPB. sICAM-1 increased until the first postoperative day (group 1: +35%; group 2: +37%) without, however, exceeding the normal range. sVCAM-1 plasma levels increased after CPB (group 1: +56%; group 2: +40%). At the end of surgery and 5 hours after CPB, sGMP-140 plasma levels were significantly higher in the hypothermic (increase from 301 +/- 34 to 582 +/- 57 ng/mL) than in the normothermic patients (increase from 310 +/- 45 to 480 +/- 32 ng/mL). On the first postoperative day, both groups showed similar, significantly elevated plasma levels of sGMP-140.

Plasma levels of circulating adhesion molecules sELAM-1, sICAM-1, and sVCAM-1 did not differ between hypothermic and normothermic CPB, indicating no differences in endothelial activation between the two groups. Only sGMP-140 plasma levels were increased more after hypothermic CPB. Additional influences of hypothermia on the coagulation system might have contributed to the higher sGMP-140 plasma levels of these patients. The definite role of circulating adhesion molecules in cardiac surgery patients remains to be elucidated.