Clinical Medicine & Physiology
Penn State 2003b & Modified 2010 ICU Ventilator Calorie Formula: Mifflin + T_max + V_E
Estimate Resting Energy Expenditure in mechanically ventilated ICU patients when indirect calorimetry is unavailable using David Frankenfield’s ASPEN-recommended Penn State 2003b and Modified 2010 (Age >= 60 & BMI >= 30) equations.
Why ASPEN endorses Penn State 2003b / 2010 over static kcal/kg guesses in ventilated ICU patients!
Static weight multipliers miss hypermetabolic fever spikes and high minute ventilation in sedated ICU patients! Derived and validated against indirect calorimetry by David C. Frankenfield et al. (2003, 2009, 2010, JPEN), the ASPEN-preferred Penn State Equations combine baseline Mifflin-St Jeor RMR (kcal/day, calculated from actual body weight) with 24-hour Maximum Body Temperature T_max (°C) and Expiratory Minute Ventilation V_E (L/min read directly off the ventilator)!
Specifically, for general adults (BMI < 30, or BMI >= 30 with Age < 60), Penn State 2003b = Mifflin * 0.96 + T_max * 167 + V_E * 31 - 6212; whereas for older obese adults (Age >= 60 AND BMI >= 30 kg/m^2, whose blunted febrile response caused 2003b to overpredict), Modified Penn State 2010 = Mifflin * 0.71 + T_max * 85 + V_E * 64 - 3085!
| ICU Patient Subgroup | Active Penn State Equation (kcal/day) | Validation Accuracy (Within +-10% of IC) |
|---|---|---|
| Non-Obese Adults OR Obese Age < 60 yr | PSU 2003b = Mifflin * 0.96 + T_max_C * 167 + V_E * 31 - 6212 | ~67%–72% unbiased agreement |
| Older Obese Adults (Age >= 60 AND BMI >= 30) | PSU 2010 = Mifflin * 0.71 + T_max_C * 85 + V_E * 64 - 3085 | ~74% agreement in elderly obesity |
Auto-Switching Penn State ICU Resting Energy Expenditure (2003b vs 2010, kcal/day)
Automatically selects Modified PSU 2010 when Age >= 60 (B3) AND BMI >= 30 (B4), or PSU 2003b otherwise, from Mifflin-St Jeor RMR (B2), 24h T_max °C (B5), and Minute Ventilation V_E L/min (B6).
=IF(OR(B2 < 600, B2 > 4000, B3 < 18, B3 > 120, B4 < 12, B4 > 90, B5 < 34, B5 > 43, B6 <= 0, B6 > 35), "Invalid ICU Ventilator or Anthropometric Inputs", ROUND(IF(AND(B3 >= 60, B4 >= 30), B2 * 0.71 + B5 * 85 + B6 * 64 - 3085, B2 * 0.96 + B5 * 167 + B6 * 31 - 6212), 0))Selected Penn State Equation Label
Displays which validated Frankenfield equation was triggered by patient age and BMI.
=IF(AND(B3 >= 60, B4 >= 30), "Modified Penn State 2010 (Age >= 60 & BMI >= 30)", "Penn State 2003b (Standard Ventilated Adult)")Try the example
Use the original values or change them to test your understanding.