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In the final part of this section we will discuss the physiologic consequences of the metabolic changes. Multiple organs are involved First of all the cardiovascular system, especially the heart is severely taxed trying to maintain the energy demands. Cardiac output doubles or triples and this increased heart work often leads to heart failure in elderly patient. Attempts to decrease energy demands are required especially the control of secondary stressors.

The increased metabolism leads to an increase in production of carbon dioxide which must be removed by increasing the work of breathing. Any lean mass loss and especially any existing lung damage will make CO₂ clearance even more difficult. The end result can be respiratory fatigue followed by pneumonia and respiratory distress. Continued use of partial ventilatory assistance may be needed until the hypermetabolism decreases.

Renal dysfunction can be manifested as a result of the marked increase in urea production caused by the removal of nitrogen from amino acids for glucose production. Pre renal azotemia or increase blood urea nitrogen is common, especially with any preexisting renal impairment. Increased urine output is needed to clear the higher solute load.

Liver dysfunction is commonly seen usually at a mild degree manifested by increased alkaline phosphatase. Hepatomegaly can can also occur. The mechanism is fat deposition in the liver caused by excess liver glucose. The excess glucose is the result of hormonally driven gluconeogenesis. Too much nutrient glucose can increase the degree of cholestasis (fatty liver).

Therefore the metabolic changes are deleterious to the entire host as a result of the energy demands and lean mass loss. Multiple organs are impacted leading to a high risk for multi organ dysfunction especially the cardiopulmonary system.

Continue on to  Burn Nutrition Module