| Popis: |
Critical illness is characterized by redistribution of energy and anabolic processes toward favoring vital functions and self-defense against danger. Prolonged critical illness is associated with uncompensated catabolism with major nitrogen loss, muscle wasting, and decreased endocrine responses. If the whole endocrine system takes part in the acute and chronic responses to critical illness, androgens, insulin, growth hormone, and thyroid hormone are the most important players in the anabolic/catabolic balance. Levels of sulfate-dehydroepiandrosterone and testosterone are commonly inappropriately low in critically ill patients, with lower levels in sickest patients. These findings have formed the rationale for several trials on replacement therapy with various androgens. Albeit conflicting conclusions from these trials, synthetic androgens such as oxandrolone may be considered as adjunct treatment in selected critically ill patients. Insulin has become a routine treatment in ICU patients to maintain blood glucose levels of less than 180 mg/dL. During the chronic phase of critical illness, growth hormone (GH) and insulin growth factor (IGF)-1 levels decrease partly as the result of decreased ghrelin levels. Yet so far, trials of GH supplementation have suggested that critically ill patients may not benefit from this treatment. Likewise, albeit promising findings in animal models of critical illness, there is no evidence from clinical trial to supplement ICU patients with thyroid hormones. |
