Predicting Mortality in the Intensive Care Unit in Patients with Pulmonary Disease Using Apache II: The Acute Physiology and Chronic Health Evaluation Classification System

The following study presents the utilization and validation of the APACHE II (Acute Physiology and Chronic Health Evaluation) severity of disease classification system in the pulmonary case mix of the intensive care unit at Huntington Memorial Hospital-Pasadena, California. APACHE II is a system of evaluating a patient's severity of illness based on specific physiological characteristics presented in the initial twenty-four hours following admission, in addition to age and the presence of comorbid conditions. From this evaluation, an APACHE II score is obtained which combined with the diagnostic category allows for the prediction of in-hospital mortality (a patient's estimated risk of hospital death). In the following study an increasing APACHE II score was correlated with an increase in percent predicted mortality and subsequently hospital death. 102 patients with a primary pulmonary disease/disorder were admitted to the intensive care unit during the study period with diagnoses including asthma/allergy, pulmonary edema, pulmonary embolus, chronic obstructive pulmonary disease, infection/pneumonia, and general respiratory conditions. The mean APACHE II score was 15.4 with a standard deviation of 7.50 and the percent predicted mortality averaged 22 percent. Survivors had a mean APACHE II score of 14.2+/- 6.19 and non-survivors had a significantly lower APACHE II score of 22.2+/- 10.7. It was found that survivors had a significantly lower APACHE II score than nonsurvivors (p