The influence of deep hypothermia on inflammatory status, tissue hypoxia and endocrine function of adipose tissue during cardiac surgery

Changes in endocrine function of adipose tissue during surgery, such as excessive production of proinflammatory cytokines, can significantly alter metabolic response to surgery and worsen its outcomes and prognosis of patients. Therapeutic hypothermia has been used to prevent damage connected with perioperative ischemia and hypoperfusion. The aim of our study was to explore the influence of deep hypothermia on systemic and local inflammation, adipose tissue hypoxia and adipocytokine production. We compared serum concentrations of proinflammatory markers (CRP, IL-6, IL-8, sIL-2R, sTNFRI, PCT) and mRNA expression of selected genes involved in inflammatory reactions (IL-6, TNF-α, MCP-1, MIF) and adaptation to hypoxia and oxidative stress (HIF1-α, MT3, GLUT1, IRS1, GPX1, BCL-2) in subcutaneous and visceral adipose tissue and in isolated adipocytes of patients undergoing cardiosurgical operation with hypothermic period. Deep hypothermia significantly delayed the onset of surgery-related systemic inflammatory response. The relative gene expression of the studied genes was not altered during the hypothermic period, but was significantly changed in six out of ten studied genes (IL-6, MCP-1, TNF-α, HIF1-α, GLUT1, GPX1) at the end of surgery. Our results show that deep hypothermia suppresses the development of systemic inflammatory response, delays the onset of local adipose tissue inflammation and thus may protect against excessive expression of proinflammatory and hypoxia-related factors in patients undergoing elective cardiac surgery procedure.