Acute illness, Co-morbidity and Mortality in a Norwegian Intensive Care Population

Abstract

Background: The need for intensive care beds is high and expected to increase. Descriptive studies of the intensive care population may reveal differences in predisposing factors and outcome within subgroups and help identify areas in need of increased prevention efforts. Objective: To describe preadmission and clinical characteristics of an intensive care population in Oslo, and to compare the characteristics and outcomes of selected subgroups of this ICU-population. Method: Prospective observational cohort study of intensive care patients aged ≥ 18, admitted to two hospitals in Oslo during a one-year period. Acute illness characteristics, co-morbidity, limitations of life-sustaining treatment and hospital mortality were studied for the overall population and stratified for a) Gender and b) Medical and surgical patients within the age groups 18-59 years and 60 and above. Results: We included 861 patients, 567 (66%) males; median age 63 years (range 18-95); 537 (62%) medical admissions and 324 (38%) surgical admissions. 632 (73%) received mechanical ventilation. Trauma (n = 191, 21%) and cardiovascular disease (n = 180, 20%) were the most common causes of admission. In patients aged 18-59, poisoning caused 56/217 (26%) of the medical admissions and medical patients had a higher prevalence of pre-existing chronic disease (157/217, 72% vs. 69/160, 43%) and Charlson comorbidity index (mean 2.0 vs. 0.7, p < 0.001) than surgical patients. In patients aged 60 and above, comorbidity was similar, but medical patients had a higher hospital mortality (143/320, 45% vs. 58/164, 34%, p < 0.05). 205 (24%) died in the ICU, and limitations of life-sustaining treatment were made in 183 (89%) cases 279(32%) died during the hospital stay. Of the 582 surviving patients 455 (78%) were discharged to home or rehabilitation, 88 (15%) to nursing homes and 39 (7%) to other institutions. Conclusion: In patients younger than 60 years, trauma and poisoning were the most common causes of admission. Within this age group, medical patients had much higher prevalence of preexisting chronic disease than surgical patients, suggesting differences in predisposing factors. The majority of the surviving patients were discharged to home or to rehabilitation, indicating a low prevalence of futile intensive care.