Title: Effect of protein composition of enteral formula on gastric content volume during continuous feeding: A randomized controlled cross-over study in healthy adults
Critically ill patients often rely on enteral nutrition. Optimal nutritional therapy is associated with better outcomes such as decreased mortality and shortened length of stay in the ICU. To reach energy targets it is recommended to initiate enteral feeding within 48 hours when oral food intake is not sufficient or not feasible. However, due to the illness and/or administration of drugs such as catecholamines and opioids, the patient’s stomach emptying can be impaired.
This can lead to elevated volumes in the stomach which is a sign of gastrointestinal intolerance, and increases the risk of aspiration.
The development of gastrointestinal intolerance is a major reason to decrease or to discontinue enteral feeding resulting in inadequate energy and nutrient intake, which increases the risk for poor clinical outcome.
Enteral nutrition formulas are often rich in casein protein. In the stomach, an acidic environment, casein can coagulate- it forms insoluble clumps. This clotting can then further delay the emptying of the stomach.
Several studies have shown that enteral nutrition formulas which consist predominantly of whey, as a source of protein, passed faster through the stomach [1,2]. Studies have also demonstrated that a defined enteral formula containing a protein combination of whey, casein, soy and pea (P4), developed at Danone Research & Innovation [3], showed less acidic clotting [4] and faster stomach emptying [5], as compared to casein-dominant formulas. The P4 formula thus might positively influence the stomach emptying of critically ill patients by its non-coagulating properties and thus benefit the patient’s nutrition altogether.
A randomized controlled cross-over study in healthy adults
The peer reviewed journal Clinical Nutrition recently published a clinical study led by researchers from the University Leuven, Belgium, and Danone Research & Innovation in the Netherlands, who investigated if enteral feeding with the noncoagulating P4 formula results in lower gastric volumes compared to a casein-dominant formula. This hypothesis was tested in a randomized, controlled, open label, cross-over single-center study.
The impact of the P4 formula on gastric content volume during and after continuous feeding was tested in healthy volunteers, who received codeine and esomeprazole. Opioids, such as codeine delay gastric emptying and esomeprazole, a proton pump inhibitor reduces the body’s acid secretion in the stomach. These drugs therefore mimic gastrointestinal conditions of critically ill patients.
This was the first study in which gastrointestinal conditions of critically ill patients were mimicked by drugs. Previous studies have investigated stomach emptying profiles in healthy individuals. To measure this, study participants need to undergo frequent magnetic resonance imaging (MRI), an accurate technique to measure gastric content volumes during continuous feeding. However, critically ill patients often cannot be investigated repetitively by MRI due to the critical condition of these patients. By mimicking gastrointestinal conditions of critically ill patients, this study thus provided a reliable comparison to the physiology of such patients.
What were the study’s results?
Results of the secondary endpoints demonstrated consistent trends in favor of the P4 product as compared to the casein-rich formula. During feeding the P4 blend resulted in lower gastric content volume compared to the casein dominant enteral formula at 180 minutes. When the enteral feeding stopped, the P4 blend resulted in lower gastric content volumes at 300 and 330 minutes compared to the casein dominant enteral formula. Also, when the continuous feeding stopped it took less time with the P4 blend to empty the volume from the stomach compared to the casein dominant enteral formula. This suggested that the P4 formula might result in faster gastric emptying.
In conclusion, the observations of secondary endpoints suggest faster gastric emptying with P4 compared to casein-rich formula, possibly due to the non-coagulating properties of the P4 blend. This study suggests patients could benefit from the P4 enteral nutrition formula, due to its accelerated gastric emptying. Further research into the impact of protein coagulation in relevant study populations is advised.
Read the full publication here: Effect of protein composition of enteral formula on gastric content volume during continuous feeding: A randomized controlled cross-over study in healthy adults – ScienceDirect