Objectives: To determine: (1) the frequency of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS); (2) the mortality associated with these syndromes and (3) the influence of risk factors, comorbidities and organ system dysfunction in the mortality of ALI patients.
Design: Prospective cohort study.
Setting: Intensive care unit (ICU) of a general university hospital in Brazil.
Patients and participants: All patients that remained in the ICU for more than 24 h were evaluated regarding the presence/development of ALI/ARDS according to the 1994 American-European Consensus Conference.
Measurements and results: One thousand three hundred and one patients were studied and analyzed regarding mortality, risk factors, comorbidities and organ system dysfunction(s). The frequency of ALI was 3.8% (50), of which ARDS was 2.3% (30) and ALI/non-ARDS 1.5% (20) (p=0.15). The ICU mortality of patients with ALI was 44.0%; in ALI/non-ARDS and ARDS patients it was 40.0% and 46.7%, respectively (p=0.43). The hospital mortality of ALI patients was 48.0%; in ALI/non-ARDS and ARDS patients it was 50.0% and 46.7%, respectively (p=0.21). A multivariate analysis demonstrated that renal (ICU and hospital: p=0.002) and hematological dysfunction (ICU: p=0.008; hospital: p=0.02) were independently associated with ICU and hospital mortality in ALI patients.
Conclusions: (1) The frequency of ALI was 3.8%, of which the frequency of ARDS was 2.3% and of ALI/non-ARDS 1.5%; (2) The ICU and hospital mortality of ALI patients was 44.0% and 48.0%, respectively; mortality rates of ARDS and ALI/non-ARDS did not differ significantly; (3) Renal and hematological dysfunction were associated with mortality in ALI patients.