Systemic Bioavailability of Enteral Protein-bound Versus Free Amino Acid Nutrition During Intestinal Malabsorption in Critical Illness
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 16
- 试验地点
- 2
- 主要终点
- systemic availability of diet-derived amino acids
研究概览
简要总结
In the current study, we willquantitate the difference in digestion and absorption kinetics of dietary whole protein versus free amino acids in vivo in critically ill patients admitted to the intensive care unit suffering from malabsorption. 16 adult, mechanically ventilated ICU patients with clinical signs of malabsorption (faecal weight >350 g/day) will be included. All patients will receive a primed continuous intravenous infusion of L-[ring2H5]-phenylalanine and L-[3,5-2H2]-Tyrosine for the duration of the study period. After reaching an isotopic steady state (1.5 hours), patients will receive either [1-13C]- phenylalanine labelled milk protein or free amino acids with an identical constitution and [1-13C]-phenylalanine.
Main study endpoint will be the splanchnic extraction of phenylalanine, calculated from systemic [1-13C]- and L-[ring2H5]-phenylalanine enrichment.
详细描述
Background of the study:
The importance of the provision of sufficient protein in critical illness is increasingly recognized. Protein malabsorption seems to be an underestimated but substantial problem in critically ill patients, limiting the amount of this important nutrient that actually becomes available within the systemic circulation. Among several contributors to malabsorption in critical illness, exocrine pancreatic insufficiency has recently emerged as a regularly occurring phenomenon during critical illness. Pancreatic insufficiency could lead to reduced digestion and subsequent uptake of enteral provided proteins. A proposed solution to this problem could be the use of elementary feeds containing free amino acids instead of whole protein. Due to the lack of easy applicable and reproducible tests for protein malabsorption the true efficacy of these feeds is still unknown. We hypothesize that enteral nutrition containing free amino acids leads to higher systemic levels of amino acids and will therefore increase the amount of dietary amino acids available for protein synthesis.
Objective of the study:
To quantitate the difference in digestion and absorption kinetics of dietary whole protein versus free amino acids in vivo in patients admitted to the ICU suffering from malabsorption.
Study design:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Double (Participant, Care Provider)
入排标准
- 年龄范围
- 18 Years 至 75 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age > 18 and < 75 years
- •Fecal weight > 350g/day
- •Critical illness of any origin (e.g. medical, surgical, trauma) requiring admittance on ICU ward.
- •Expected ICU stay for the duration of the study protocol
- •Mechanically ventilated (PaO2/FiO2 ratio of >100 and <300)
- •Nasogastric tube in situ
- •Receiving full enteral nutrition without gastric residual volumes
- •Arterial (any location) line in situ
- •Flexi-seal system in situ
排除标准
- •Proven (pre-existing) intestinal disease that potentially limits normal gut function and absorption of nutrients (e.g. IBD, short-bowel, entero-cutaneous fistulas including a surgical enterostomy)
- •Proven (pre-existing) primary pancreatic disease or obstruction of the pancreatic duct of any origin (e.g. pancreatitis, carcinoma).
- •Patients who are moribund (not expected to be in ICU for more than 48 hours due to imminent death)
- •A lack of commitment to full aggressive care during the first week due to severity of illness, comorbidities and potential harm from maximal treatment (anticipated withholding or withdrawing treatments)
- •Absolute contraindication to enteral nutrients (e.g., gastrointestinal [GI] perforation, obstruction or no GI tract access for any reason)
- •Receiving parenteral nutrition.
- •Nasoduodenal or nasojejunal feeding tube
- •Renal dysfunction defined as a serum creatinine >171 umol/L or a urine output of less than 500 ml/last 24 hours
- •Patients requiring chronic veno-venous hemofiltration
- •Patients on ECMO/ELS
- •Cirrhosis - Child Pugh class C/D liver disease
- •Patients with primary admission diagnosis of burns (>30% body surface area)
- •Weight less than 50 kg or greater than 100 kg
- •Pregnant patients or lactating with the intent to breastfeed
- •Previous randomization in this study
- •Enrolment in any other interventional study
- •Milk/lactose allergy
- •Previous participation in a 13C amino acid tracer study within the last year
结局指标
主要结局
systemic availability of diet-derived amino acids
时间窗: 8 hours
The main study endpoint in this study is the systemic availability of enteral administered protein-bound or free amino acid nutrition, including the rate of appearance (Ra) of dietary derived phenylalanine. Modified Steele's equations will be applied to plasma enrichments of L-\[ring-2H5\]-phenylalanine, L-\[1-13C\]-phenylalanine enrichment, L-\[ring-2H4\]-tyrosine and L-\[3,5-2H2\]-tyrosine.
次要结局
- Total plasma amino acids (AAmax [μmol/L])(8 hours)
- Plasma insulin (insulinmax [mU/L])(8 hours)
- Intestinal absorption capacity (energy provided - fecal energy loss x 100%)(2 x 24 hours)
- Fecal elastase (µg elastase / g feces)(2 x 24 hours)
- Plasma glucose (glucosemax [mmol/L])(8 hours)
- Fecal presence of L-[1-13C]-phenylalanine(2x 12 hours)