A study on the role of noninvasive ventilation in mild-to-moderate acute respiratory distress syndrome

Indian J Crit Care Med. 2015 Oct;19(10):593-9. doi: 10.4103/0972-5229.167037.

Abstract

Aim: There is sparse data on the role of noninvasive ventilation (NIV) in acute respiratory distress syndrome (ARDS) from India. Herein, we report our experience with the use of NIV in mild to moderate ARDS.

Materials and methods: This was a prospective observational study involving consecutive subjects of ARDS treated with NIV using an oronasal mask. Patients were monitored clinically with serial arterial blood gas analysis. The success of NIV, duration of NIV use, Intensive Care Unit stay, hospital mortality, and improvement in clinical and blood gas parameters were assessed. The success of NIV was defined as prevention of endotracheal intubation.

Results: A total of 41 subjects (27 women, mean age: 30.9 years) were included in the study. Tropical infections followed by abdominal sepsis were the most common causes of ARDS. The use of NIV was successful in 18 (44%) subjects, while 23 subjects required intubation. The median time to intubation was 3 h. Overall, 19 (46.3%) deaths were encountered, all in those requiring invasive ventilation. The mean duration of ventilation was significantly higher in the intubated patients (7.1 vs. 2.6 days, P = 0.004). Univariate analysis revealed a lack of improvement in PaO2/FiO2 at 1 h and high baseline Acute Physiology and Chronic Health Evaluation II (APACHE II) as predictors of NIV failure.

Conclusions: Use of NIV in mild to moderate ARDS helped in avoiding intubation in about 44% of the subjects. A baseline APACHE II score of >17 and a PaO2/FiO2 ratio <150 at 1 h predicts NIV failure.

Keywords: Acute hypoxemic respiratory failure; acute lung injury; acute respiratory distress syndrome; mechanical ventilation; noninvasive ventilation.