Impact of Endocrine Disorders in Critically Ill Patients

Patients presenting with different critical illnesses often display secondary endocrine systemic conditions. In another respect, patients registered in intensive care units (ICUs) might present major clinical findings that are attributable to the precipitating illness and might mask underlying primary endocrine diseases. In this chapter we will analyze two specific conditions, dysglycemia and low-T3 syndrome (lowT3S), often occurring in different critical ill patients. In the last years several studies reported that dysglycemia is an independent risk factor of mortality for critically ill patients. Dysglycemia, including stress-induced hyperglycemia, hypoglycemia, or serum blood fluctuation, has a poor prognostic impact especially in subjects who did not know to have diabetes before admission in ICU. As far as lowT3S is concerned, it is also known as non-thyroidal illness syndrome and indicates a condition in which an impairment in thyroid function can be detected in the absence of appropriate changes in TSH levels. In this chapter we will analyze the underlining mechanisms and consequences for both dysglycemia and lowT3S in different critical illnesses and the most appropriate therapeutic approaches.