[Evaluation of mortality of patients admitted to ICU for the last 12 years].

We evaluated mortality of 2689 patients admitted to the Intensive Care Unit, Osaka University Hospital from January, 1987 to December, 1998. The patients were divided into 3 groups. Group A consisted of 1408 patients who underwent cardiovascular surgery, group B, 1082 patients who underwent other surgical procedures and group C, 199 patients who were transferred from the department of medicine. We studied mortality rate, causes of death, correlation between length of ICU stay and mortality rate, and mortality rate among age groups for 12 years. The main causes of death were cardiac failure and sepsis in group A, and respiratory failure and sepsis in group B and C. Mortality rate in each group showed no significant change for the last 12 years. Those who stayed more than 2 weeks in ICU showed a significantly higher mortality rate (p < 0.0001). Thus, length of ICU stay and mortality rate showed a positive correlation (p < 0.0001). The youngest group (age 0-1) showed a significantly higher mortality rate than other age groups (p < 0.0001). As sepsis was the most important cause of death in all the groups, the prevention and treatment of infection are the most important issue in our ICU to reduce mortality rate.