Correct!
2. High PEEP, low tidal volume
Repetitive opening and closing of alveoli upon mechanical ventilation can cause injury in lung parenchyma, which is called ventilator induced lung injury (VILI). It can lead to multi-organ failure through dissemination of proinflammatory cytokines and enzymes, therefore, a protective ventilation strategy is pivotal in patients with ARDS or ALI. The ARDS Clinical Network recommends a low tidal volume (< 8 ml/kg PBW) with a goal plateau pressure ≤ 30 cm H2O (3). A recent meta-analysis showed high PEEP might increase survival in ARDS patient, but may be harmful in ALI patients without ARDS (4). However, most of these studies excluded patients with known interstitial lung disease such as idiopathic pulmonary fibrosis and cryptogenic organizing pneumonia, and it is unclear whether these mechanical ventilator strategies for ARDS or ALI work the same way in ILD patients. One recent retrospective study with ILD patients showed a high PEEP > 10 cm H2O was associated with a significant survival benefit (5). Although there is no definitive evidence, a low tidal volume with high PEEP is the current recommendation for ILD patients who need mechanical ventilation to minimize volutrauma, atelectotrauma and maximized oxygenation.
There was little improvement in our patient with antibiotic treatment, and ventilator weaning was difficult. The diffuse chest x-ray and CT findings along with the nonspecific BAL cytology suggested the diagnosis of cryptogenic organizing pneumonia.
What is the best initial treatment for an acute exacerbation of cryptogenic organizing pneumonia? (click on correct answer to move to next panel)