[Mechanical ventilation in Brazil: epidemiological aspects]

There are few epidemiological studies in mechanical ventilation, and the aim of the study is to show how this procedure is being used in Brazil.

A 1-day point prevalence study was performed in 40 ICUs, with 390 patients; 217 of these patients were in mechanical ventilation. The results evaluated were the characteristics of ventilated patients, their distribution in Brazil, the mechanical ventilation's causes, the main ventilatory modes, the more important ventilators settings, and the weaning stage of mechanical ventilation.

The median age of the ventilated patients was 66 years old. The median APACHE II was 20, while the median time of mechanical ventilation was 11 days. Acute respiratory failure occurred in 71% of the patients, coma in 21.2%, acute exacerbation of chronic respiratory failure in 5.5%, and the neuromuscular disease in 2.3%. The volume-controlled ventilation (VCV) (30%), the pressure support ventilation (PSV) (29.5%), and the pressure-controlled ventilation (PCV) (18%) were the ventilatory modes most used; the PSV had been the main mode in weaning (63.5%). The median of tidal volume (8 mL/kg) was higher in VCV. The median of maximal inspiratory pression (30 cmH2O) and the median of positive end-expiration pressure (PEEP) (8 cmH2O) were higher in PCV.

The predominance of ventilated patients in ICUs was marked by clinical severity of them, and a longer hospital stay time; acute respiratory failure was the principal mechanical ventilation cause; VCV and PSV ventilated more patients, with PSV being more used in weaning patients.