Flow rate of nutrient preparations through nasogastric tubes.

Experiments have been carried out in vitro to determine the relationships between the internal diameter of fine-bore nasogastric tubes, the viscosity of nutrient solutions, and the flow rate that can be achieved in the enteral feeding of surgical patients. It was found that such tubes are capable of delivering 3-5 l of nutrient solution in 24 h without a pump. The findings are discussed in relation to the supply of nitrogen and energy to the patient.