Clinical Research Directory

Respiratory Quotient and Phosphate Changes During Early Critical Illness

Critically ill patients often experience major changes in metabolism during the first days of intensive care. When nutrition is started or increased after a period of reduced intake, some patients may develop refeeding syndrome, a potentially serious condition associated with shifts in electrolytes such as phosphate, potassium, and magnesium. This study will investigate whether changes in respiratory quotient (RQ), measured by indirect calorimetry, are associated with changes in serum phosphate during the first intensive care week. RQ reflects the balance between oxygen consumption and carbon dioxide production and provides information about which energy substrates are being used by the body. A rising RQ may indicate increasing carbohydrate metabolism and could potentially provide an early physiological marker of metabolic changes associated with refeeding. Mechanically ventilated adult intensive care patients will undergo daily indirect calorimetry during the first five days of the study period, with an additional measurement on day 7 when feasible. Serum phosphate and other electrolytes, nutritional intake, insulin treatment, ventilator parameters, and relevant physiological variables will be recorded at corresponding time points. The study will also evaluate how well established screening criteria for refeeding risk, including the NICE criteria, identify patients who subsequently develop metabolic changes consistent with refeeding. No study-specific changes to nutrition or other treatment will be made. This accurately reflects the observational nature of the study: routine IC, laboratory and nutritional data are collected without changing treatment.

Gastrointestinal Hormones and Metabolomic Profiling Following Mixed-Meal Tolerance Tests in Patients at Risk of Refeeding Syndrome

Introduction: Refeeding syndrome (RS) is a life-threatening metabolic complication of nutritional support. Prolonged fasting, frequently observed in malnourished patients referred for percutaneous endoscopic gastrostomy (PEG), induces histological and ultrastructural changes in the intestinal mucosa, potentially influencing RS development. Mixed-Meal Tolerance Tests (MMTT) combined with metabolomics allow dynamic assessment of serum glucose, gastrointestinal hormones and cellular metabolites, which may help to elucidate RS pathogenesis and assess patient risk. Objective: The present study aims to perform MMTT in PEG-fed patients to evaluate enteroendocrine hormone responses and metabolomic profiles following a prolonged fasting period and subsequent enteral refeeding. Methods: This prospective, single-center study includes adults referred for PEG after at least one month of oral intake below 50% of energy needs. The MMTT will be performed at PEG placement and after 3-6 months of enteral nutrition. Serial blood samples will be collected from baseline up to 120 minutes post-meal to measure serum glucose, insulin, C-peptide, electrolytes and gastrointestinal hormones (GLP-1/GIP/Ghrelin/Peptide YY), and for metabolomic profiling by spectroscopy. Clinical and nutritional data will be prospectively recorded. Statistical and multivariate analyses will assess metabolic and hormonal changes over time and their potential association with patient refeeding syndrome risk and clinical outcome. The study was approved by the institutional ethics committee, and patient informed consent will be obtained. Conclusion: This study integrates MMTT and metabolomic profiling to characterize hormonal and metabolic responses during fasting and refeeding in high-risk PEG patients. Findings are expected to reveal underlying mechanisms of RS, identify potential predictive biomarkers, and improve individualized risk stratification and nutritional management.

Comparing High-protein Vs. Standard Protein Nutritional Support in Critically Ill Patients At Risk for Refeeding Syndrome

The goal of this clinical trial is to determine the optimal protein administration strategy for enhancing both nutritional and clinical outcomes, as well as reducing complications and mortality in ICU patients at risk for refeeding syndrome (RS). This study will include critically ill patients at risk for RS who are receiving supportive nutrition. The primary hypothesis is that higher protein intake will lead to a decreased incidence of refeeding syndrome. It is also expected that patients receiving more protein will have better clinical outcomes, lower mortality, and shorter ICU and hospital stays.

Refeeding Syndrome in Critically Ill Children

Refeeding syndrome (RFS) is the a metabolic disturbance which occurs as a result of reinstitution of nutrition in people who are starved, severely malnourished, or metabolically stressed because of severe illness. When too much food or liquid nutrition supplement is eaten during the initial three to seven days following a malnutrition event, the production of glycogen, fat and protein in cells may cause low serum concentrations of potassium, magnesium and phosphate.

Prevention of Refeeding Syndrome

To determine effects of different caloric density intake in prevention of refeeding syndrome in critically ill children