Hypermetabolism in the Initial Phase of Intensive Care Is Related to a Poor Outcome in Severe Sepsis Patients.

OBJECTIVE

To assess the incidence of hypermetabolism, defined as high resting energy expenditure, in severe sepsis ICU patients, and evaluate the suitability of excessive resting energy expenditure (REE) as a risk factor of their clinical outcome.

METHODS

In a single-center, prospective, six-month observational study in China, the measured REE (MREE) was estimated daily using indirect calorimetry (IC) for the first 5 days of ICU admission. The predicted REE (PREE) was determined using the Harris-Benedict equation. ICU severity criteria (APACHE II and SOFA scores), baseline and health characteristics, and laboratory test results, were compared between the hyper-metabolic (MREE/PREE ratio ≥1.3) and the normometabolic (MREE/PREE ratio <1.3) groups, and between the survivor and non-survivor groups, classified according to 28-day mortality.

RESULTS

Of the 62 included ICU patients (age, 57.1 ± 19.5 years), 34 patients (55%) were hypermetabolic. The 28-day mortality rate in the hypermetabolic and normometabolic groups was 35 and 18%, respectively (p < 0.001). The MREE/PREE ratio and C-reactive protein (CRP) plasma concentration were significantly higher in non-survivors than survivors (p = 0.017), and were significantly (p < 0.05) associated with 28-day mortality (ORMREE/PREE = 1.018, 95% CI, 1.010-2.544, p = 0.031 and ORCRP = 1.010, 95% CI, 1.005-2.173, p = 0.025, respectively).

CONCLUSION

In critical sepsis patients admitted to ICU, the MREE/PREE ratio may be a valuable evaluation index of the clinical outcome.