Clinical characteristics and outcomes of patients with acute lung injury and ARDS.

BACKGROUND: Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are critical illnesses associated with significant morbidity and mortality. AIMS: This was designed to assess various etiologies of ALI/ARDS, to determine the correlation between the diagnostic criteria and need of mechanical ventilation, and to correlate biochemical factors with the outcome of patients. SETTINGS AND
DESIGN: An observational, prospective study was conducted in a medical intensive care unit (MICU) of a tertiary care hospital, for a period of 1 year.
MATERIALS AND METHODS: This study encompassed 58 consecutive cases of ALI/ARDS admitted to a MICU as per AECC guidelines. Patients excluded were with cardiac failure, chronic kidney diseases with fluid overload, and age below 12 years. STATISTICAL ANALYSIS: The data were analysed applying χ2 -test, multivariate logistic regression analysis of significance, using computer-based program SPSS.
RESULTS: There were more males (74%) than females, and presentation was more common in the younger age group, with a total mortality of 57%. Factors attributable for ALI/ARDS were malaria in 16 patients (27.6%), leptospirosis in 12 (20.7%), malaria with dengue in 3 (5.2%), undiagnosed fever in 16 (27.6%), pneumonia in 8 (13.8%), urinary tract infection in 2 (3.4%), and pancreatitis in 1 (1.7%) patient. Out of 41 patients with PaO 2 /FiO 2 <200, 40 patients required invasive ventilation, and out of 17 patients with PaO 2 /FiO 2 >200, 11 patients though initially managed on noninvasive ventilation (NIV) subsequently required invasive ventilation, and remaining six were successfully managed on NIV. Out of 41 patients requiring mechanical ventilation, 36 had LIS >2.5, whereas only 3 out of 17 patients with LIS <2.5 required mechanical ventilation.
CONCLUSION: Malaria, leptospirosis, and undiagnosed fever were the main etiologies followed by pneumonia, urinary tract infections, and pancreatitis. Both the PaO 2 /FiO 2 ratio and lung injury score (LIS) at the time of admission were significant predictors of the outcome and of necessity of mechanical ventilation. PaO 2 /FiO 2 was a better predictor of duration of stay at the intensive care unit than the LIS. Sepsis, acidosis, hypotension, and multiorgan failure were individual predictors of mortality in patients with ALI/ARDS while age, sex, anemia, thrombocytopenia, renal failure, hepatic failure, and X-ray picture were not predictors of the outcome.