Practical implications of "personalized nutrition therapy".

Area of Science:

• Critical care medicine
• Nutritional science
• Metabolic research

Background:

• Personalized nutrition therapy in ICUs often defaults to indirect calorimetry (IC), but predictive equations (PEs) are more prevalent due to practical constraints.
• A shift in critical illness nutrition support questions the necessity of exact energy targets for personalized therapy.

Purpose of the Study:

• To review evidence comparing IC and PE-based nutrition support in ICUs.
• To examine practical issues like timing, patient selection, and nutrition adequacy.
• To redefine the focus of personalized nutrition therapy in critical care.

Main Methods:

• Systematic reviews and meta-analyses from 2020-2025 were analyzed.
• Evidence comparing indirect calorimetry (IC) and predictive equations (PEs) for nutrition support in the ICU was examined.
• Practical considerations and outcomes of IC vs. PEs were highlighted.

Main Results:

• Systematic reviews show mixed results: some suggest IC reduces short-term mortality, while others indicate increased mechanical ventilation days.
• IC-based protocols tend to deliver more calories than PE-based methods, risking overfeeding.
• Significant discrepancies between measured and predicted energy expenditure exist in special populations (burns, obesity, elderly).

Conclusions:

• Indirect calorimetry (IC) provides more accurate metabolic demand assessment than PEs, particularly in complex patients, but faces logistical challenges and uncertainty regarding optimal calorie targets.
• Current evidence for early IC implementation in the ICU is inconclusive.
• Future personalized critical care nutrition may rely on novel patient identifiers (phenotypic, metabolomic, mechanistic).