Steroids should be used in Cardiac Surgery

Steroids should be used in Cardiac Surgery Truncated abstract By nature, cardiac surgery is a provocation to the immune system. The use of foreign material in extracorporeal circulation (ECC) along with ischaemia / reperfusion triggers its activation. A logical approach seems to be to reduce the inflammation to reduce the negative effects. The bottom line will be written - not through a battery of blood tests - but by authors describing clinical outcome. Ischaemia is a prerequisite in most modern cardiac surgery. The reduction of injury from ischaemia is through cardioplegia is a success story in modern medicine. Still there are untoward effects – especially in operations for complicated procedures with prolonged ischaemic time or problematic hearts. Reperfusion by itself also can cause damage to the myocardium but is obligatory for complete recovery. Experimental studies show a large number of untoward effects of ischaemia and reperfusion. Firstly, ischaemia and reperfusion cause reduction in cellular high energy phosphates. This depletion of energy is harming the ionic pumps leading to an unstable cell membrane leading to influx of water, sodium and calcium. Infusion of cardioplegia may lead to increased coronary artery resistance which indicates microvascular damage (19). Ischaemia and reperfusion have further been shown to impair constituents of the cell membrane. Specifically, our group showed that the GS -proteins in the beta adrenergic response chain were seriously damaged during reperfusion (22). Secondly, cardiac surgery induces changes in the blood associated with inflammation. Soluble factors that promote adhesion of leukocytes to the endothelium such as sICAM, sVCAM were found elevated after cardiac surgery (7). Increase in heat shock proteins concomitant with increase in Interleukin-6 was also seen after cardiac surgery (6). Fontes et al (8) demonstrated leukocyte activation and upregulation of the surface receptor CD-11 in monocytes and neutrophils. The upregulation of this receptor in monocytes was found to correlate with postoperative atrial fibrillation. Further, reperfusion after cardioplegic arrest increased the expression of E-selectin, interleukins, heat shock proteins, tumour necrosis factor and adhesion molecules in myocardial biopsies during cardiac surgery (26). There is also more circumstantial evidence. From our own database of more that 10 000 patients undergoing cardiac surgery, two groups of patients each consisting of more than 1200 patients were analyzed. There was a significant correlation between the CRP onwards from the postoperative day 3 - and occurrence of postoperative atrial fibrillation. Those patients developing atrial fibrillation had higher CRP. In a 4- year period we analysed a group of patients above 75 years of age. Those who were reopened for bleeding had significantly higher preoperative CRP values. The importance of the last finding remains to be seen. In 36 patients undergoing coronary artery surgery Volk et al (27) found an increased release of oxidized glutathione, protein carbonyl groups and malondialdehyde during reperfusion after ischaemia. This indicated an increased postischaemic production of reactive oxygen species (ROS) and increased lipid peroxidation. Reversing heparin with protamine activates complement (C3a, C4a) (13). Thus, there is solid evidence for postischaemic cellular impairment and perioperative inflammation during cardiac surgery.