Diagnostic Value of Pulmonary Ultrasound in the Diagnosis of Ventilator-associated Pneumoniae

Diagnosis and monitoring iconographic lung infection is essentially limited to chest radiography. But this one to bed is a source of information generally unreliable routine.

Lung ultrasound is now an additional technique for confirmation of diagnosis and followed by community acquired pneumonia and monitoring of ventilator-associated pneumonia. The specific pathophysiology of VAP makes particularly efficient lung ultrasound in the diagnosis and monitoring of these attacks. The patient mechanically ventilated, the colonization of the airways is responsible for a continuous seeding of the tracheobronchial tree. As the lesions are scattered throughout the lung parenchyma and are centered on a bronchiole; although there is a predominance of households in the areas most dependent lung. VAP is therefore characterized by inflammatory tissue expansion to the periphery, predominant at the lower lobes and partnering with a ventilation loss varies with the severity of the pneumonia.

Thus, it can be found at an early stage some cells infected around a bronchiole in contact with infected acini normally ventilated. At an advanced stage, this extension to the whole parenchyma results in the widespread presence of small outbreaks in pleural. They are easily and specifically detected by ultrasound in the form of vertical artifacts irregular spacing (irregular Lines B) or small pictures (<0.5 cm) rounded HYPOECHOIC (jucta pleural consolidation) for reliable diagnosis of VAP. The success of an antibiotic is detected by the disappearance of B lines and pleural jucta consolidations. The failure of antibiotic therapy by the appearance of new jucta pleural consolidations which may merge giving lobar consolidation. Community-acquired pneumonia is characterized by the spread of infection in a home adjacent pulmonary segments by providing a systematized typical lobar reached. The diagnosis and monitoring of community-acquired pneumonia is mainly based on monitoring the number and size of household lobar consolidation which is not sufficient for pneumonia Ventilator. This latest study shows that the intensity ultrasound signs is proportional to the extension of outbreaks (lobar consolidations homes and mini homes jucta pleural consolidation). Moreover unlike biological biomarkers such as procalcitonin, it does not reflect the intensity of inflammation.

Inclusion criteria

• Patients in mechanical ventilation for at least 48 hours
• and new or extension of a radiological image

with at least two of the following clinical criteria:

• Body temperature ≥ 38.5 ° C or <36 ° C
• Leukocytes> 10 * 103 / ml or <4 * 103 / ml or> 10% immature cells (in the absence of other known causes).
• hypoxemia with PaO 2 <60 mmHg or a P / F <300
• secretions purulent tracheal

Exclusion criteria

• Patient with known pneumonia
• Patient under 18 years
• Mechanical ventilation <48h
• contraindication of pulmonary endoscopy