Loading Calculator...
Please wait a moment
Please wait a moment
Calculate caloric and protein requirements for critically ill patients using validated formulas including the Penn State equation for ventilated patients and Mifflin-St Jeor for metabolic rate estimation.
Clinical Use Only
This calculator is intended for healthcare professionals. Results should be used in conjunction with clinical assessment and institutional protocols.
EE = (Mifflin × 0.96) + (Tmax × 167) - 6212
Where: EE = Energy Expenditure, Tmax = Maximum temperature (°C)
Used for mechanically ventilated ICU patients
Men: BMR = (10 × W) + (6.25 × H) - (5 × A) + 5
Women: BMR = (10 × W) + (6.25 × H) - (5 × A) - 161
Where: W = weight (kg), H = height (cm), A = age (years)
| Patient Type | Protein (g/kg/day) |
|---|---|
| Standard ICU patient | 1.2-1.5 |
| Burns, trauma | 1.5-2.0 |
| Obese (BMI > 30) | 2.0-2.5 (based on IBW) |
| Renal failure (not on dialysis) | 0.8-1.0 |
The Penn State equation (2003) is specifically designed for mechanically ventilated ICU patients and accounts for temperature and minute ventilation. Use Mifflin-St Jeor with activity factors for non-ventilated patients or when Penn State parameters are unavailable.
Current guidelines recommend starting enteral nutrition within 24-48 hours and advancing to goal over 48-72 hours. However, use caution in hemodynamically unstable patients and monitor for feeding intolerance. Early aggressive feeding may increase complications in some patient populations.
For obese patients (BMI > 30), consider using adjusted body weight or ideal body weight for caloric calculations. Protein requirements may be higher (2.0-2.5 g/kg IBW) to preserve lean body mass. Hypocaloric high-protein feeding (50-70% of calculated needs) may be appropriate.
Yes, indirect calorimetry is the gold standard for measuring energy expenditure and should be used when available, especially in patients with severe malnutrition, obesity, prolonged ICU stay, or when predictive equations are likely to be inaccurate.
Screen all ICU patients for refeeding risk before initiating nutrition. High-risk patients include those with BMI < 16, unintentional weight loss > 15% in 3-6 months, minimal intake > 10 days, or low baseline potassium, phosphate, or magnesium. Use the Refeeding Risk Calculator for detailed assessment.
Enteral nutrition (gastric or post-pyloric) is preferred when the GI tract is functional. Consider parenteral nutrition only when enteral feeding is contraindicated or unable to meet > 60% of needs after 7-10 days. Combined enteral and parenteral nutrition may be used in select cases.
Monitor daily caloric and protein intake, weekly weight (accounting for fluid status), prealbumin or CRP trends, nitrogen balance if available, and functional outcomes. Reassess nutritional requirements every 48-72 hours and adjust the feeding plan based on clinical response and tolerance.
ICU patients have increased micronutrient needs due to metabolic stress, losses, and antioxidant consumption. Ensure adequate supplementation of vitamins (especially thiamine, vitamin D, vitamin C), trace elements (zinc, selenium), and electrolytes. Consider higher doses in burns, trauma, or prolonged critical illness.