[Extracorporeal circulation as a risk factor in heart surgery]

Extracorporeal circulation has a complex influence on the biology of the various organ systems. Knowledge of interactions with biomaterials and the resultant pathophysiological reactions is still very limited. The safety of the heart-lung machine lies, to a great extent, in the hands of the operator; precautions against breakdowns and accidents are necessary. The effects of the extracorporeal circulation process manifest themselves clinically as organ malfunctions. The risk is clearly associated with the age of the patient and the duration of the procedure. The fact that the extracorporeal circulation--and with it the heart operation--affects not just a single organ, but rather the entire organism, requires detailed knowledge of the general state of health of the patient to be operated upon. Only on this basis can the necessary individual operational strategies be developed.