Metabolism and the Impact of Protein Intake in Chronic Critically Ill Adult Patients: Protocol for a Unicentric Prospective Cohort Study (MetaChronic Study)
试验速览
- 阶段
- 不适用
- 状态
- 进行中（未招募）
- 入组人数
- 100
- 试验地点
- 1
- 主要终点
- Resting Energy Expenditure (REE)
研究概览
简要总结
Survival of critically ill patients has improved, resulting in a growing population of chronically critically ill (CCI) individuals with prolonged organ dysfunction, mechanical ventilation, and high morbidity. While nutritional guidelines during the acute phase are well established, evidence on protein intake in CCI patients is limited. Inflammation may influence metabolic responses and clinical outcomes, highlighting the need for prospective studies.
The MetaChronic Study is a single-center, prospective cohort designed to describe metabolic trajectories and evaluate the effect of protein intake on outcomes in critically ill adults. Resting energy expenditure will be measured by serial indirect calorimetry, protein and caloric intake will be recorded weekly, and inflammation will be assessed using C-reactive protein (CRP) and procalcitonin. Secondary objectives include subgroup analyses, assessment of protein delivery routes, and exploration of interactions between protein intake, caloric intake, and inflammation.
详细描述
This single-center, longitudinal observational study enrolls critically ill adults who require invasive mechanical ventilation (IMV) for at least 48 hours and remain in the Intensive Care Unit (ICU) for more than 7 days. Participants are followed in-hospital for up to 42 days after ICU admission, unless discharged, deceased, or unable to continue accurate nutritional monitoring due to transition to oral feeding for nutritional purposes. The final assessment occurs on Day 90 after onset of critical illness, when functional status is evaluated using the Portuguese validated version of the EuroQol 5-Dimension Questionnaire (EQ-5D), administered either by telephone or in person depending on patient location.
Baseline characterization includes:
- Demographic information (age, sex)
- Pre-ICU hospitalization days
- Nutritional risk assessed with the modified Nutrition Risk in the Critically Ill (NUTRIC) score (without interleukin-6)
- Category of critical illness (septic with/without abdominal surgery, trauma with/without head injury, neurocritical, and other categories)
- Severity upon ICU admission measured by the Simplified Acute Physiology Score II (SAPS II)
Metabolic assessment is performed using serial indirect calorimetry beginning on Day 7 of ICU stay and repeated one to three times per week up to Day 42 or until hospital discharge. Feasibility requires absence of air leaks in the respiratory system. For patients on invasive mechanical ventilation (IMV), measurements follow device requirements (fraction of inspired oxygen < 70% and positive end-expiratory pressure < 12 cmH₂O); for spontaneous ventilation, measurements are obtained in canopy mode at FiO₂ 21%. Weekly metabolic values are calculated as the average of available measurements.
Protein intake is recorded according to routine clinical practice and quantified weekly after Day 7, expressed in grams (g) per kilogram of adjusted body weight per day (g/kg/day). Protein delivered as amino acids is converted to grams of protein using a standard factor (100 g hydrolyzed protein = 83 g amino acids). Total caloric intake is also quantified weekly, including enteral and parenteral nutrition as well as non-nutritional caloric sources such as glucose-containing solutions and propofol.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Adult critically ill patients admitted to Intensive Care Unit > 7 days
- •Invasive mechanical ventilation (IMV) > 48 hours
排除标准
- •Active oncological disease
- •Neuromuscular diseases
- •Confirmed or predicted Glasgow Coma Score < 10 at 14 days in Intensive Care Unit
- •Pregnant women
结局指标
主要结局
Resting Energy Expenditure (REE)
时间窗: From Day 7 of Intensive Care Unit stay through Day 42 or until Intensive Care Unit, whichever occurs first.
Resting energy expenditure will be measured by indirect calorimetry using a calorimeter, which calculates energy expenditure in kilocalories (Kcal) per day from oxygen consumption and carbon dioxide production. Serial measurements will characterize metabolic trajectories during prolonged critical illness.
次要结局
- Mortality(At Intensive Care Unit (ICU) discharge; at Day 28 after ICU admission; at hospital discharge; at Day 90 after ICU admission.)
- Duration of Invasive Mechanical Ventilation(From endotracheal intubation to extubation or transition to intermittent ventilation via tracheostomy, up to Day 42 of ICU stay.)
- Protein Intake(From Day 7 of Intensive Care Unit stay through Day 42 or until Intensive Care Unit discharge, whichever occurs first)
- Days Alive and Out of the Hospital(From hospital admission through Day 90.)
- Discharge Destination(At Day 42 after Intensive Care Unit admission)
- Functional Status at 90 Days(At Day 90 after Intensive Care Unit admission)
- Tracheostomy Duration(From tracheostomy insertion through decannulation, up to 90 days.)
- Number of Infections(From Intensive Care Unit admission through Day 30)
- Days Alive and Out of the Intensive Care Unit(From Intensive Care Unit admission through Day 90.)
研究者
Sílvia Margarida Correia de Castro
Principal Investigator, Intensive Care Physician
Universidade do Algarve