Endothelium activation during prolonged extra-corporeal circulation

Objectives

The aim of this study was to monitor the plasma levels of soluble adhesion molecules in patients undergoing cardiac surgery in extracorporeal circulation (EC). We investigated the relationships between the levels of adhesins released during the prolonged extracorporeal circulation and postoperative morbidity.

Study design

We assessed 10 patients (NYHA class II or III) undergoing elective cardiac surgery with flat-sheet membrane oxygenation. The procedures were: coronary artery bypass grafting, cardiac valve implantation or both. The duration of CPB was 135–246 min, core temperature 28–31°C. The patient statuses were assessed daily with SOFA and Marshall MODS scores. The soluble vascular cell adhesion molecule (sVCAM-1), soluble intercellular adhesion molecule (sICAM-1), soluble endothelial leukocyte adhesion molecule (sELAM-1), lactate levels and WBC were measured before induction of anaesthesia, during EC, one and two days after operation.

Materials and methods

Arterial blood samples were collected on heparin. Plasma was immediately obtained by centrifugation and then frozen at -70°C until the assay was performed. Activity of sVCAM-1, sICAM-1 and sELAM-1 was measured using enzyme- linked immunoabsorbent assays (ELISA).

Results

The plasma concentrations of sVCAM-1 were significantly higher during the entire study (mean 954.38, 818.60, 1291.09, 1264.09 ng/ml). In four patients who developed postoperative multiple organ dysfunction failure the sVCAM-1 were significantly higher than in those with uneventful recovery. sICAM-1 levels after operation were above the normal range (mean 272.88, 236.97, 294.64, 410.52 ng/ml). There was no significant differences in plasma sELAM-1 levels during the whole time of observation (mean 43.07, 29.45, 48.57, 49.18 ng/ml before anaesthesia, during surgery, on day 2 and 3, respectively). sICAM-1 levels after operation were above the normal range (mean 272.88, 236.97, 294.64, 410.52 ng/ml).

Conclusions

Extracorporeal circulation with membrane oxygenation is followed by a significant endothelium response and release of soluble adhesion molecules into the bloodstream. There is the correlation between the markedly increasing level of sVCAM-1 and sICAM-1 and the appearance of postoperative complications.