Abstract: Due to aging, elderly patients experience gradual deterioration in organ functions and weakened gastrointestinal absorption capacity. After falling ill, they often suffer from gastrointestinal dysfunction, which can increase mortality and infection rates, prolong hospitalization duration, lead to poor clinical prognosis, and reduce quality of life. Elderly critically ill patients often cannot eat independently and require enteral nutrition (EN) and parenteral nutrition (PN) support. For this vulnerable geriatric population with critical conditions, nutritional support therapy plays a crucial role in improving malnutrition, yet may simultaneously induce various nutrition-related complications. This article summarizes the complications associated with EN and PN, introduces preventive measures and therapeutic approaches for these complications, aiming to enhance nutritional support efficacy for elderly critically ill patients, ultimately improving their clinical outcomes and quality of life.

Key words: aged, critically illness, enteral nutrition related complications, parenteral nutrition related complications