When is parenteral nutrition most commonly used?

Parenteral nutrition is most commonly used in patients with digestive system disorders because these conditions can impair the ability to absorb nutrients through the gastrointestinal tract. Patients with conditions such as severe Crohn's disease, extensive bowel resections, or gastrointestinal obstructions may be unable to ingest or absorb sufficient nutrients orally. In such cases, parenteral nutrition provides a necessary alternative to deliver nutrients directly into the bloodstream, ensuring that the body receives essential vitamins, minerals, carbohydrates, proteins, and fats without relying on the digestive system.

While malnourished elderly patients may benefit from nutritional support, parenteral nutrition is specifically reserved for cases where the digestive system cannot function adequately. Weight loss regimens generally focus on oral dietary modifications rather than invasive methods like parenteral nutrition. Oral intake being safe negates the need for parenteral nutrition, which is employed primarily when oral feeding is either ineffective or impossible.