Serial evaluation of the Multiple Organ Dysfunction Score, Sequential Organ Failure Assessment and Logistic Organ Dysfunction scores to predict ICU mortality in mixed critically ill patients

Introduction

Multiple organ dysfunction is common cause of death in critically ill patients. The aim of this study is to perform a serial assessment of the Multiple Organ Dysfunction Score (MODS), Sequential Organ Failure Assessment (SOFA) score and Logistic Organ Dysfunction (LOD) score and to compare their ability in predicting ICU mortality.

Methods

All of the data were collected prospectively on consecutive ICU admissions over 24 months at a tertiary referral university hospital in Thailand. The MODS, SOFA and LOD scores were calculated on initial admission and repeated every 48 hours. Discrimination was evaluated by the area under the receiver operating characteristic curve (AUC). The Δ score was defined as the difference between the score at the reference time and the initial score.

Results

See Figure 1. A total of 2,054 patients were enrolled in the study. The initial, maximum and Δ scores of all the organ dysfunction scores correlated well with ICU mortality. The maximum all-model scores up to six correlated with a mortality rate less than 5%, while those higher than 10 and 14 were associated with a mortality rate greater than 55% and 77%, respectively. When Δ LOD-48 increased more than four points, the ICU mortality went up to 79%. The maximum score of all models had better ability for predicting ICU mortality than the initial or Δ score. The AUCs for maximum scores were 0.892 (95% CI = 0.872–0.911) for the MODS, 0.907 (95% CI = 0.890–0.924) for the SOFA and 0.920 (95% CI = 0.903–0.936) for the LOD. The AUC of the Acute Physiology and Chronic Health Evaluation (APACHE) II score was 0.905 (95% CI = 0.867–0.923). No statistical difference existed between the maximum score and the APACHE II score.

Figure 1

Correlation of the Δ-48 score of the MODS, SOFA and LOD scores with ICU mortality.

Conclusion

Serial assessment of organ dysfunction during the ICU stay is reliable with ICU mortality. The maximum scores is the best discrimination power comparable with APACHE II score in predicting ICU mortality.