Effects of conventional CPB and mini-CPB on neutrophils CD162, CD166 and CD195 expression

OBJECTIVE

Cardiac surgery is known to trigger a systemic inflammatory response. While the use of conventional cardiopulmonary bypass (CPB) results in profound inflammation, modified mini-CPB is considered less harmful. We evaluated the impact of cardiac surgery on the expression of CD162, CD166, CD195 molecules and their association with the type of CPB used.

METHODS AND RESULTS

Twenty-four patients were enrolled in our study. Twelve of them were operated using conventional CPB while the other twelve patients underwent surgery with mini-CPB. Blood samples were analysed by flow cytometry. We observed a significant increase in median fluorescence intensity of CD162 and CD195 that peaked instantly after surgery and normalized to the baseline value on the 1^st day post surgery, whereas CD166 was initially down-regulated and its median fluorescence intensity (MFI) value increased to the baseline in the next few days.

CONCLUSION

We observed immediate changes in the expression of CD162, CD166, and CD195 molecules on the neutrophils after surgery in both study groups of patients. The intensity of the observed changes was significantly greater in the group of patients who underwent conventional CPB compared to patients who underwent mini-CPB cardiac surgery.

Inhibitory CD200R and proapoptotic CD95/CD95L molecules on innate immunity cells are modulated by cardiac surgery

Introduction:

Cardiac surgery directly initiates a systemic inflammatory response with the activation of both cellular and humoral parts of the immune system. Exaggerated immune system activation is associated with a risk of life-threatening multi-organ dysfunction (MOD) and increased morbidity and mortality in the postoperative period. The immune system response is regulated and terminated by inhibitory mechanisms, including the regulatory membrane molecules, such as CD200R, CD95, CD95L and soluble sCD200R.

Methods:

We measured the expression of CD95, CD95L, CD200R and sCD200R molecules in granulocyte and monocyte populations in blood samples of 30 patients who underwent coronary artery bypass grafting (CABG) using cardiopulmonary bypass (CPB). Samples collected before surgery, after surgery and in the postoperative period were analyzed by flow cytometry and ELISA.

Results:

We found a significant increase in the percentage of granulocytes featuring the anti-inflammatory molecule CD200R (from 5% to 17.8%) after surgery. We presume that these cells were less susceptible to apoptosis because they rarely expressed CD95 as the CD200R+CD95– granulocyte sub-population prevailed. Only a small percentage of CD200R+ granulocytes expressed simultaneously CD95 (from 0.5 to 2.06 %). This small population of CD200R+CD95+ cells decreased expression of CD200R after surgery and, thus, was likely to be a source of increased sCD200R in serum (from 96 to 294 ng/mL). Also, the expression of CD95L on CD200R+ granulocytes and CD95 on CD200R+ monocytes was affected by surgery. The percentage of CD200R+ monocytes was elevated on the 1st postoperative day (from 30.6 to 49.4 %) and dropped below the preoperative value on the 7th day after surgery (from 30.6 to 19.8 %). This population comprised mainly CD200R+CD95+ monocytes in which the enhanced expression of CD95 was found.

Conclusion:

Our data show that the expression of CD200R, CD95 and CD95L was influenced by cardiac surgery and imply the role of these membrane molecules in cell regulation–inhibition and apoptosis following cardiac surgery.

The long pentraxin PTX3: a candidate anti-inflammatory mediator in cardiac surgery

Coronary artery bypass grafting (CABG) is performed with the use of cardiopulmonary bypass (CPB) and cardioplegic arrest (CA) of the heart. The advantage of this technique, alternatively referred to as “on-pump” surgery, resides, for the surgeon, in relatively easy access to and manipulation with the non-beating, bloodless heart. However, the advantage that is, thereby, gained by the patient is paid off by an increased susceptibility to postoperative systemic inflammatory response syndrome (SIRS). Under unfavorable conditions, the inflammatory syndrome may develop into life-threatening forms of MODS (multiple organ dysfunction syndrome) or even MOFS (multiple organ failure syndrome). Deliberate avoidance of CPB, also known as “off-pump” surgery, attenuates early postoperative inflammation throughout its trajectory of SIRS→MODS→MOFS, but, in the long run, there appears to be no substantial difference in the overall mortality rates. In the last years, our knowledge of the pathophysiology of surgical inflammation has increased considerably. Recent findings, highlighting the as yet rather obscure role of pentraxin 3 (PTX3) in these processes, are discussed in this review article.

Risk factors for postoperative respiratory mortality and morbidity in patients undergoing coronary artery bypass grafting

ABSTRACT

Nowadays, coronary artery bypass grafting (CABG) is considered to be one of the most common surgical procedures. This procedure has been the main topic in many clinical research studies, which have assessed the effect of the procedure on patients’ outcomes. Like other surgical procedures, this procedure is also accompanied by a number of unwanted complications, including those of the respiratory system. Since the respiratory system plays an integral role in defining the clinical outcome of patients, improvements in studies that can assess and predict clinical outcomes of the respiratory system, assume greater importance. There are a number of predictive models which can assess patients in the preoperative period and introduce a number of risk factors, which could be considered as prognostic factors for patients undergoing CABG. The respiratory system is among the clinical systems that are assessed in many prediction scoring systems. This review assesses the main studies which have evaluated the possible risk factors for postoperative respiratory mortality and morbidity, in patients undergoing CABG.