Assessing the impact of patient characteristics and process performance on rural intensive care unit hospital mortality rates.

Abstract

To examine the relationship between patient characteristics, processes of care, and risk of hospital mortality in rural intensive care units (ICU). Retrospective data analysis of ICU patients admitted to 19 rural Iowa hospitals between 1992 and 1994. ICUs in rural Iowa hospitals. ICU patients treated on mechanical ventilators meeting eligibility criteria. Patient age (odds ratio = 1.03, p < .01), a higher Acute Physiology and Chronic Health Evaluation II score (odds ratio = 1.06, p < .01), and a longer pre-ICU length of stay (odds ratio = 1.14, p < .05) were associated with a higher risk of death. Seven processes of care were examined (i.e., laboratory work, nursing assessment, stress ulcer protection, immobilization protection, nutritional management, ventilator management, and weaning). Considerable variation was observed between hospitals in performance of processes of care. Controlling for patient characteristics, better performance in ulcer protection (odds ratio = 0.1, p < .05) and ventilator management (odds ratio = 0.03, p < .05) were related to lower risk of mortality. A model incorporating both patient characteristics and processes of care achieved higher predictive accuracy than a model containing only patient characteristics (area under the receiver operating characteristic curve: 0.80 vs. 0.70, p < .01). Most of the variation in mortality was explained by differences in patient physiologic and demographic characteristics at ICU admission. After adjusting for patient characteristics, better performance in some processes of care would have significant impact on reducing risk of mortality.