Table 1 A review of guidelines and other consensus recommendations for nutritional management of patients with obesity in critical care

Performing malnutrition screening and assessment

ESPEN, ASPEN/SCCM: A general clinical assessment should be performed to assess for malnutrition in the ICU, until a specific tool is validated [23, 24]

Current tools are not validated for patients with obesity and may rely on imprecise measures, such as BMI

Assessment of patients with obesity should consider the possibility of underlying malnutrition, based on clinical reasoning, signs and symptoms of macro/micronutrient deficiencies, and poor muscle quality despite the presence of muscle mass

ASPEN/SCCM: Assessment in patients with obesity should also include biomarkers of metabolic syndrome, comorbidities, and inflammation markers [24]

Malnutrition may be underrecognized in patients with obesity

Monitor patients with obesity for refeeding syndrome over the course of treatment

Estimating energy needs

ESPEN: In patients with obesity, energy intake should be guided by IC. If IC is unavailable, energy intake can be based on adjusted body weight (actual body weight − ideal body weight) × 0.25 + ideal body weight) [23]

There is no consensus on how to estimate energy needs for critical care patients with obesity (ideal, actual, vs adjusted body weight)

IC is preferred to estimate energy needs among those with obesity in the ICU

ASPEN/SCCM: IC should be used when available/feasible; otherwise use a published predictive equation or simple weight-based equation: 11–14 kcal/kg actual body weight per day for patients with BMI in the range of 30–50 and 22–25 kcal/kg ideal body weight per day for patients with BMI > 50 [24].

Predictive equations are easily calculated but were developed in populations without obesity

Predictive or weight-based equations should be only one aspect of a nutrition assessment, especially for patients with obesity

Review individual nutritional requirements and factors that influence energy needs on a regular basis to adjust intake

ASPEN: If IC unavailable, use Penn State Eq. 2010 or modified Penn State Equation depending on patient age [25]

Manage patients with the intention of reducing net protein catabolism without concurrent feeding complications, worsening of physical function, or clinical outcomes when compared to withholding nutritional therapy

Estimating protein needs and recognizing and addressing risk of sarcopenic obesity

ESPEN: Protein delivery should be guided by urinary nitrogen losses or lean body mass determination (using CT or other tools); if urinary nitrogen losses or lean body mass determination are not available, protein intake can be 1.3 g/kg “adjusted body weight”/day [23]

Clinicians may be unaware of risk of muscle mass loss in patients with obesity

Protein needs may be higher in critically ill patients with obesity

ASPEN/SCCM: 2.0 g/kg ideal body weight per day for patients with BMI of 30–39.9 and up to 2.5 g/kg ideal body weight per day for patients with BMI ≥ 40 [24]

Weight loss in critical illness may contribute to the loss of lean body mass rather than just fat mass

Individualized approach to nutritional and body composition assessments

ASPEN: “High-protein feeding may be started with 1.2 g/kg actual weight or 2–2.5 g/kg ideal body weight, with adjustment of goal protein intake by the results of nitrogen balance studies” [25]

A 24-h urine collection for a nitrogen balance determination may not be practical or feasible for some institutions

Frequently reassess clinical status and nutritional needs

Choosing the ideal nutritional regimen

ASPEN/SCCM: Hypocaloric, high-protein regimen for patients with obesity; assess regularly for adequate protein intake [24]

Renal status and nitrogen balance should be carefully monitored with high-protein intake, especially for older patients or those with underlying kidney disease [25, 26]

Consider an individualized approach to nutritional management that achieves a higher protein intake without overfeeding

ASPEN “A trial of hypocaloric, high-protein feeding is suggested in patients who do not have severe renal or hepatic dysfunction” [25]

Maintain an individualized approach that recognizes changing nutritional needs over the course of illness

Using IMN

ASPEN/SCCM: “While an exaggerated immune response in obese patients implicates potential benefit from immune-modulating formulas, lack of outcome data precludes a recommendation at this time” [24]

Obesity creates a pro-inflammatory environment. The ability of nutrition to modulate this inflammation in patients with obesity is unclear

It is unclear whether IMN would be beneficial for routine use among ICU patients with obesity. However, IMN is suggested for routine use in patients with TBI and in the surgical ICU. Additionally, IMN should be considered for patients with severe trauma [23]