Enteral Feeding Intolerance in Adult Patients Receiving Mechanical Ventilation: A Comprehensive Review

Enteral feeding intolerance, a type of gastrointestinal dysfunction, is common in adults receiving mechanical ventilation, yet its definition and clinical assessment remain variable. If untreated, this syndrome may lead to underfeeding, which is associated with worse patient outcomes.

To describe what is known about enteral feeding intolerance, including who is at risk, clinical symptoms, identifying measures used, treatment, and clinical implications for nursing practice.

Enteral feeding intolerance is identified by (1) changes in gastrointestinal function, (2) high gastric residual volume, and/or (3) inadequate delivery of enteral nutrition. A combination of gastrointestinal symptoms and high gastric residual volume is generally used to diagnose the condition. The most common symptoms are vomiting, abdominal distention, absence of bowel sounds or flatus, and diarrhea. Administration of promotility agents and reduction of the enteral formula rate are most often used to reduce the effects of enteral feeding intolerance until it resolves.

Many gastrointestinal assessment findings are subjective and lack precision. Although the routine measurement of gastric residual volume is no longer standard practice, it is indicated in patients at risk for enteral feeding intolerance.

Nurses should become familiar with how to assess for and treat enteral feeding intolerance, as well as rule out other common gastrointestinal complications. Clinical biomarkers are needed to objectively identify enteral feeding intolerance in critically ill patients.