This study evaluates the feasibility of a high whey-protein enteral nutrition formula in 20 ventilated ICU patients. The primary endpoint of study is the feasibility to attain the individualized protein target (≥1.2 g/kg ideal body weight/day) 96-hours after ICU admission. Secondary endpoints include tolerance and efficacy in terms of the amino acid response in blood.

In the present pilot study, the investigators will use a high whey-protein nutrition formula during the first four days of ICU admission. The reason for using a high protein nutrition is that the investigators previously found that an early high protein intake in non-septic non-overfed patients was associated with lower hospital mortality (Weijs PJM et. al., Critical Care 2014,18). Furthermore, during the first days of critical illness tolerance to full enteral nutrition is often diminished. The use of a high protein nutrition will facilitate an early high protein intake.

The whey protein is hydrolysed. Hydrolyzation of protein prevents coagulation and subsequent solidification in the digestive tract and therefore promotes efficient absorption of the protein. Of all nutrition proteins, whey protein has the largest leucin content. Leucin is crucial for muscle protein synthesis. (Meyer RF, et.al.: BMC Gastroenterol 2015, 15), (Marik PE: Ann Intensive Care 2015,5:51)

Our previous observational data also showed that early overfeeding was associated with higher mortality, while an intake of 80-100% of measured energy expenditure at day 4 of ICU admission was associated with lower mortality. (Weijs PJM et. al., Critical Care 2014, 18)

Therefore, the energy target during the first four days will be 90% of the measured Energy Expenditure (EE). To optimize energy intake, the investigators will measure EE by metabolic monitoring (Deltatrac®, Datex, Helsinki, Finland), If metabolic monitoring is not available, the investigators will assess EE from the ventilator derived VCO2 (8.19*VCO2). (Stapel S, et.al., Critical Care 2015,19:370)

Inclusion Criteria:

• Admission to the intensive care unit
• Age >18 years
• Mechanical ventilation
• Expected intensive care stay of four days or longer

Exclusion Criteria:

• Contraindication for enteral nutrition (gut ischemia, obstruction or perforation)
• Expected intolerance for enteral nutrition (paralytic ileus)
• Inability to start enteral nutrition within 24-hours due to logistic reasons (i.e. surgery or other interventions)
• Short bowel syndrome
• Child C liver cirrhosis or acute liver failure
• Dialysis dependency
• Requiring other specific enteral nutrition for medical reason
• Extensive treatment limitations
• Written deferred patient or proxy consent is not obtained
• Participation in another intervention study
• Inability to measure energy expenditure (pulmonary air leakage)

Ventilated critically ill patients in the ICU