Simplified prediction rule for prognosis of patients with severe community-acquired pneumonia in ICUs

Study objectives: To develop a simplified prognostic prediction rule for patients admitted to ICUs for severe community-acquired pneumonia (CAP), Setting: Six ICUs in the north of France. Patients: Five hundred five patients admitted to ICUs over a 9-year period (from 1987 to 1995) for severe CAP, Interventions: Retrospective prognosis analysis and multivariate analysis using a credit scoring technique. Measurements: The primary outcome measure was ICC mortality. Results: Among the 505 patients, 472 were eligible for the prognosis study The ICU mortality rate was 22.9%. Multivariate analysis identified, on the basis of the patient's medical history and initial examination on ICU admission, six independent predictors of mortality: age greater than or equal to 40 years, anticipated death within 5 years, nonaspiration pneumonia, chest radiograph involvement > 1 lobe, acute respiratory failure requiring mechanical ventilation, and septic shock. An initial risk score based on these factors classified patients into three risk classes of increasing mortality: 4% in class I, 25% in class II, and 60% in class III. Multivariate analysis of events occurring during ICU stay identified three independent predictors of mortality: hospital-acquired lower respiratory tract superinfections, nonspecific CAP-related complications, and sepsis-related complications. An adjustment risk score based on these factors was essential to accurately predict the final outcome of patients in the initial risk class II. Conclusions: As an aid to clinicians in stratifying the prognosis of patients with severe CAP, the simplified prediction rule used in this study could be useful for therapeutic decisions and appropriate care.