Bolus Versus Continuous Enteral Tube Feeding

The trial has been designed in accordance with the Recommendations for Interventional Trials (SPIRIT 2013) and the Consolidated Standards for Reporting of Trials CONSORT guidelines.

Patients who meet the study inclusion criteria (severe trauma patients, surgical patients and medical patients with sepsis, with inserted nasogastric/nasoduodenal feed-ing tube) will be eligible to participate, especially patients who are mechanically ventilated. The last criterion is not a necessary precondition (a module of indirect calorimetry will be used in these patients). The necessary condition is the elimination of shock within 24 hours from the ICU admission and tolerance of trophic enteral feed-ing (20ml/hour) at for the period of at least 24 hours. Patients will be randomized in a ratio of 1:1 within 72 hours of their admission to receive bolus or continuous enteral feeding (sealed envelopes method). In both groups, the same goals of energy and protein will be observed (Day 1-2: E 15 kcal/kg/day, protein 0.8-1 g/kg/day; Day 3-4: E 20 kcal/kg/day, protein 1. 2 g/kg/day; Day ≥ 5: E 25 kcal/kg/day, protein 1.5-2 g/kg/day), according to protocol. The bolus enteral group will receive the amount of enteral nutrition in six boluses (per 60min dose), the continuous enteral group will receive the amount using a pump, within the timeframe of 6am-24pm. The need for parenteral nutrition will be determined by treating clinical staff independently to group allocation.

Demographic data collection: (weight, high, BMI) and conditions (trauma, surgical, medical patients), Acute Physiology and Chronic Health Evaluation (APACHE) Sequential Organ Failure Assessment (SOFA), Nutritional Risk Screening (NRS 2002).

Daily observations: glucose, mean glucose changes, insulin (IU/d), energy and protein intake (administered calories divided by the calculated energy expenditure and administered protein divided by calculated protein intake) - Adjusted/calculated energy and protein (%). Feeding intolerance (tolerating less than 40% of requirements via the enteral route for ≥ 3 days, diarrhea ≥ 500ml per day or five bowel actions). Mechanically ventilated patients (Resting Energy Expenditure (REE) and Respiratory Quotient (RQ) measured with indirect calorimetry) Day 1, 3, 5, 7: Nutritional parameters (serum albumin prealbumin, C-reactive protein (CRP), urine urea, N balance).

Day 1 and 7: Muscle layer thickness (QMLT by ultrasound measurement and mid-upper arm circumference) and muscle strength (dynamometer) from baseline to discharge. Outcomes of muscle strength/ultrasound and dynamometer) will be measured by an investigator blinded to the group allocation.