Intensive care of the elderly: Value of the score systems APACHE II and III?

Objective:Scores like APACHE (Acute Physiology And Chronic Health Evaluatio n) were evaluated for unselected intensive care unit (ICU) admissions. Can they also be used for risk stratification and quality assurance in selected subgroups like elderly patients? Methods: Over a 3-year period data of all admissions of a 12 bed interdisci plinary ICU were collected. APACHE II and III scores and probabilities of h ospital deaths were compared with observed outcomes. The discriminatory pow er was evaluated by calculating the areas under the receiver operating char acteristic (ROC) curves. Calibration was analyzed with standardized mortali ty ratios (SMR) and the Hosmer-Lemeshow goodness-of-fit statistic. Results: Of 3382 admissions due to exclusion criteria, 2795 patients were a nalyzed, 1396 (49,9 %) of these were greater than or equal to 65 years, mea n age 75 (65-99) years. 62.5 % were non-operative, 37.5 % postoperative adm issions, 35 % after emergency operations. ICU mortality was 11.7 %, hospita l mortality 25.1 %. The areas under the ROC curves were 0.77 for APACHE II and 0.79 for APACHE III (whole collective 0.83 and 0.85, respectively). The SMR was 1.17 for APACHE II and 1.23 for APACHE III: compared with 1.06 and 1.;22 for all patients, respectively. Calibration for elderly patients was insufficient for APACHE IT (Hosmer-Lemeshow chi-square = 19, p < 0.025) as well as for APACHE III (chi-square = 41, p < 0.001), while it was good for all patients for APACHE II (chi-square = 12, p > 0.1) but not So for APACH E III (chi-square = 48, p < 0.001). Conclusions: APACHE II and III both show good discrimination for elderly pa tients although a little inferior than for all patients. Both scores can be used for risk stratification of elderly ICU patients. Mortality prognosis is not sufficient for geriatric patients although APACHE II calibrates well for all. Application of these scores for quality assurance in selected sub groups like elderly patients cannot be recommended based on these data.