Parenteral nutrition as a tool for sarcopenic patients in the intensive care unit.

Abstract

Parenteral nutrition (PN) is an essential tool in the therapeutic arsenal for supporting patients unable to feed enterally. Its historical development was crucial, notably Robert Elman's demonstration of the safety of intravenous amino acids and the success of Stanley Dudrick and Jonathan Rhoads in 1968 in achieving sustained total parenteral nutrition (TPN). In the Intensive Care Unit (ICU), PN is indispensable due to the hypercatabolic state and the risk of acquired muscle weakness (AMD-ICU). The nutritional strategy focuses on mitigating muscle loss through high protein intake (1.2–2.0 g/kg/day), starting with moderate caloric intake (15–20 kcal/kg/day) in the acute phase. The implementation of PN requires rigorous monitoring due to the risk of complications, such as central venous catheter (CVC)-associated infections and metabolic imbalances. In the context of sarcopenia and severe catabolism, the effectiveness of parenteral nutrition (PN) depends on a comprehensive therapeutic approach. While protein intake is crucial, its protective effect on muscle mass depends on the simultaneous implementation of early mobilization and progressive exercise strategies, even in sedated patients. Despite advances, there remains a need to generate robust scientific evidence to establish uniform and precise guidelines for the application of PN in heterogeneous critically ill populations.