Nutritional Status Assessment in Critically Ill Patients
Limitations of Traditional Markers
- Albumin is a negative acute-phase reactant that falls acutely with inflammation, acute or chronic stress, and infection, making it insensitive to actual nutritional status in critically ill patients, according to the American Journal of Kidney Diseases 1
- The presence of acute or chronic inflammation limits the specificity of serum albumin as a nutritional marker, and an elevated C-reactive protein negates the relationship between albumin and actual protein intake, as noted by the American Journal of Kidney Diseases 1
- Prealbumin is also a negative acute-phase reactant, meaning levels decline during inflammation or infection, limiting its specificity as a pure nutritional marker, as stated by the American Journal of Kidney Diseases is not available, but Praxis Medical Insights: Practical Summaries of Clinical Guidelines 2
- Non-nutritional factors that confound albumin interpretation include infection, inflammation, hydration status, peritoneal or urinary albumin losses, and acidemia, as reported by the American Journal of Kidney Diseases 1
Alternative Assessment Tools
- The American Society for Parenteral and Enteral Nutrition (ASPEN) and the European Society for Clinical Nutrition and Metabolism (ESPEN) recommend using the Nutritional Risk Screening 2002 (NRS-2002), which incorporates BMI, weight loss, food intake, and disease severity, for hospitalized patients 3
- The Global Leadership Initiative on Malnutrition (GLIM) approach uses reduced food intake as one of five criteria for diagnosing malnutrition, as endorsed by the GLIM 3
Practical Monitoring Approach
- Monitor food intake daily in malnourished patients using semi-quantitative methods, and trigger nutritional intervention when intake is ≤50% of energy requirements over 3 days, as recommended by Praxis Medical Insights: Practical Summaries of Clinical Guidelines, but the American Journal of Kidney Diseases does not provide this information, however Praxis Medical Insights: Practical Summaries of Clinical Guidelines 3
- Measure C-reactive protein alongside any visceral protein measurement to interpret inflammatory status, as suggested by Praxis Medical Insights: Practical Summaries of Clinical Guidelines, however the American Journal of Kidney Diseases also provides this information 1, 3
Critical Pitfalls to Avoid
- Do not interpret albumin or prealbumin in isolation without considering the patient's inflammatory status, as warned by Praxis Medical Insights: Practical Summaries of Clinical Guidelines, however the American Journal of Kidney Diseases does not provide this information, but Praxis Medical Insights: Practical Summaries of Clinical Guidelines 3
- Do not wait for laboratory confirmation to begin nutritional support if clinical signs of malnutrition are present, as advised by Praxis Medical Insights: Practical Summaries of Clinical Guidelines, however the American Journal of Kidney Diseases does not provide this information, but Praxis Medical Insights: Practical Summaries of Clinical Guidelines 3