[Substrate and energy metabolism in intensive care patients under long-term mechanical ventilation]

In eight polytraumatized ventilated surgical patients studies on substrate utilization and energy expenditure were performed for six days following trauma, while receiving our routinely administered parenteral diet containing 1 g amino acids/kg/d and 6.4 g carbohydrate/kg/d. The results obtained from this study indicate that we can not meet energy and substrate requirements using this infusion regimen in severely injured intensive care patients. Within the entire period of investigation all patients demonstrated the typical signs of a disturbed posttraumatic metabolism. This fact was underlined by permanently elevated glucose blood levels, low respiratory quotients - indicating mainly fatty acid oxidation - and clearly negative nitrogen balances.