Assessment of the Diagnostic Capacity of the Mini-broncho Alveolar Lavage Performed Through a Suction Catheter

The aim of this study is to develop a safe and effective technique to take sample for lower respiratory tract cultures easy to perform in conditions of acute respiratory failure and spontaneous ventilation for patients admitted in intensive care unit for acute infectious pneumonia and non intubated. The investigators perform sample collection with a mini bronchoalveolar lavage catheter introduced by nasotracheal way through a suction catheter. The purpose of the study is to assess the microbiological diagnostic capacity of this new technique.