In a patient on long-term home enteral nutrition who develops nausea, what is the most likely cause?

• A. Frequent Use of Sorbitol-Containing Medications
• B. Gastric Outlet Obstruction
• C. Low Osmolarity Formula
• D. Sudden Decrease in Enteral Feeding Rate

Answer: (B)

When vomiting or nausea develops during long-term enteral nutrition, a problem with the stomach emptying the contents into the small intestine is a common culprit. Gastric outlet obstruction blocks the passage of formula at the pylorus or distal stomach, so the stomach cannot empty properly. This leads to gastric distention and a buildup of feeding before the obstruction, which triggers nausea and often vomiting, and can be accompanied by early satiety and weight loss. In the long-term EN setting, such an obstruction can arise from conditions like scarring from peptic ulcers, pyloric stenosis, a gastric lesion, or a bezoar, all of which prevent forward flow of the feeding.

Other options don’t fit as well because they don’t typically produce a primary obstruction or delayed gastric emptying. Sorbitol-containing medications cause osmotic GI upset and diarrhea rather than a focal gastric outlet blockage. Low osmolarity formulas are designed to reduce intolerance, not cause it. A sudden decrease in feeding rate would more likely adjust the volume and symptoms rather than create a persistent obstruction and nausea. Therefore, the most likely cause of nausea in this scenario is a gastric outlet obstruction.