One year's experience with the APACHE II severity of disease classification system in a general intensive care unit.

The APACHE II sickness score was applied prospectively for one year in a general intensive care unit in Saudi Arabia. Two hundred and ten patients were studied, 66 of whom died in hospital. The mean APACHE II score of survivors was 11 (SD 7.1) and of non-survivors, 25.3 (SD 8.8). The mean Risk of Death was 13.3% (SD 13.1) for the survivors and 47.2% (SD 25.8) for non-survivors. The differences in APACHE score and Risk of Death between survivors and non-survivors are highly significant (p less than 0.0005 for both). No patient survived who had a Risk of Death greater than 60% and none died with a Risk of Death less than 7%. The sensitivity of the APACHE II system in predictions of death can be improved if the scores on the day of admission and on the 3rd day are taken into account.