Table 2 Unidimensional biomarkers in nutrition
Biomarker | Indicator of nutritional risk | Valid measure of metabolic response to nutrition | Indicates a biological mechanism related to the intervention and clinical outcomes | Feasible for use in ICU clinical practice or trials | Additional procedures and samples required |
|---|---|---|---|---|---|
Baseline clinical parameters: BMI, NUTRIC Score | Yes | No | No | Yes | None |
Whole-body protein balance | Unknown | Yes | Yes | No | Isotope infusion; frequent sampling of blood and exhaled breath |
Nitrogen balance | Unknown | No | Yes | Yes | Collection of urine over 6–24 h and blood sampling |
Insulin resistance | Unknown | Unknown | Yes | Yes | None |
Albumin, pre-albumin | Yes | No | Unknown | Yes | Blood sampling |
Body composition (skeletal muscle ultrasound, CT) | Yes | Unknown | Yes | Unknown | Imaging |
Markers of inflammation (IL-6, CRP) | Yes (IL-6) | Unknown | Yes | Yes | Plasma ELISA, PaxGene PCR |