Serial evaluation of the Sequential Organ Failure Assessment score in non-coronary medical patients
© BioMed Central Ltd 2005
Published: 7 March 2005
To determine the usefulness of daily Sequential Organ Failure Assessment (SOFA) score  for prediction of mortality in non-coronary medical ICU patients.
Patients and methods
A prospective, observational study was conducted from May 1997 to April 2001. Nine hundred and nineteen consecutive adult patients admitted to the ICU for more than 24 hours were included (10,164 patient days). The SOFA score was calculated on admission and every 24 hours until discharge.
Study patients had a mean age of 59 ± 17 (± standard deviation) years; 70% were male, mean ICU length of stay was 11 ± 15 days, mean APACHE II score after 24 hours was 19 ± 10. Initial, maximum and mean (sum of daily SOFA scores divided through days of ICU stay) SOFA scores correlated well with mortality in the ICU (25.7%). The ability of the SOFA to discriminate between ICU survivors and non-survivors was assessed using the area under the receiver operating characteristic curve (AUC). The AUC was largest for the mean SOFA score (0.90, 95% confidence interval: 0.88–0.93) and the maximum SOFA score (0.88, 95% confidence interval: 0.86–0.91). A mean SOFA score of more than 7 corresponded to a mortality of more than 83% versus 10% for a mean score of 7 or less. When analyzing trends in the first 48 hours, regardless of the initial score, the mortality was 56% when the score increased, 24% when it remained unchanged, and less than 20% when it decreased.
Sequential assessment of organ dysfunction during the first few days of ICU admission is a good indicator of prognosis. Both the mean and the maximum SOFA scores are particularly useful predictors of ICU outcome. Independent of the initial score, an increase in SOFA score during the first 48 hours predicted in our sample a mortality rate of 56%.