[Diagnostic aspects and analytical problems of glycemia monitoring in intensive care unit patients]

Abstract

Blood glucose is one of the most frequently ordered laboratory tests used mainly for diagnosis and monitoring of diabetes treatment. However, disturbances of glucose metabolism occur also in patients without diabetes in critical illnesses of various etiopathogenesis, including acute coronary syndrome, multi-organ injuries, sepsis, septic shock, burns or post-surgery trauma. The disturbances are caused by increased secretion of stress hormones and inflammatory cytokines resulting in insulin resistance and hyperglycemia. These changes worsen the course of the disease and prognosis. The management of critically ill patients should include the control of glycemia and maintaining it in the target range. The treatment includes intravenous insulin and glucose administration with monitoring of glycemia. Other abnormalities of glucose metabolism observed in various diseases are hypoglycemic states including neonatal hypoglycemia. Assays of blood glucose in critically ill patients treated in intensive care units should be performed using point-of-care testing (POCT) techniques. Measurements of real time glycemia provide the base for rapid achievement and maintaining glucose target values. It is particularly important when glucose concentrations decide on immediate physician's action, e.g. change in insulin dosage or compensation of hypoglycemia. POCT glucose assays are now included in critical care tests panel and glucose assays may be performed using various dedicated analyzers. This kind of test has its specificity associated with the kind of employed material and the measurement techniques adjusted to "fresh" blood as material of testing, distinguishing results of glucose POCT assays and results obtained in the laboratory. Tests are performed in the blood samples immediately after collection sample and take no longer than a few minutes. Real time glycemia control in intensive care unit patients has become an important part of present medical procedures.