Although predicted REE calculated using the Penn state 1988 method agreed (ICC 0.61, p=0.00014) with the measured REE, all three predictive equations had a fixed bias and appeared to be inaccurate for predicting REE for liver transplant recipients.

Therefore, precise measurements using indirect calorimetry may be helpful when treating critically ill patients to avoid underestimating or overestimating their metabolic needs.

Rationale: The aim of this study was to compare predictive equations with indirect calorimetry and identify the appropriate energy expenditure requirement of liver transplant(LT) recipients in South Korea.

Methods: This prospective observational study was conducted in a surgical ICU in an academic tertiary hospital over three months. Thirty mechanically ventilated patients who had received liver transplants and were expected to stay in the ICU more than 2 days were studied. Resting energy expenditure(REE) was measured 48 hours after ICU admission using open-circuit indirect calorimetry. Theoretical REE was estimated using three predictive equations: Harris-Benedict methods, lreton-Jones ventilated, and Penn state 1988. The REEs derived from each predictive equation were compared with the measured REE using an intraclass correlation coefficient (ICC) and a Bland-Altman plot.

Inclusion Criteria:

• mechanically ventilated patients who had received liver transplants and were expected to stay in the ICU more than 2 days were studied.

Exclusion Criteria:

• Refusal
• patients who were extubated before 36 hrs

Patients who had received liver transplants