Gastrointestinal and biliopancreatic response to continuous nasogastric feeding in man: effect of increasing nutrient infusion rate

Abstract

Nasogastric feeding is a safe and inexpensive procedure used in various conditions to provide artificial nutritional support. However, the effects of increasing energy load of nutrients during continuous enteral nutrition on gastric physiology, biliopancreatic secretions and intestinal absorption of nutrients are unknown. A nutrient solution (1 kcal/ml, 15% proteins, 30% lipids, 55% carbohydrates) was randomly infused at three rates, 1.5, 3.0 and 4.5 ml/min, into the gastric antrum in 6 volunteers over a 6 h period. Gastric emptying, gastric and biliopancreatic secretion, and intestinal absorption were studied using a perfusion technique. Gastric emptying rate reached the infusion rate during continuous enteral nutrition at 1.5 and 3.0 ml/min although a steady state was not reached at 4.5 ml/min. During feeding at 1.5, 3.0 and 4.5 ml/min, the median gastric pH values were 1.9, 2.3 and 3.0 respectively and the total gastric volumes at the sixth hour were 78 ± 13, 226 ± 43 and 539 ± 101 ml respectively. There was a significant increase in biliary and pancreatic secretion between 1.5 and 3.0 ml/min but not between 3.0 and 4.5 ml/min. Gastric emptying became the limiting factor in lipid and in carbohydrate absorption. Our study shows that, in healthy volunteers, the maximal infusion rate of a nutrient solution infused into the stomach should be approximately 3 ml/min to avoid complications such as nausea, vomiting, regurgitation and pulmonary inhalation.