Acute lung injury in caused by all of the following except

ARDS, most cases (>80%) are caused by a relatively small number of clinical disorders: severe sepsis syndrome and/or bacterial pneumonia (~40-50%), trauma, multiple transfusions, aspiration of gastric contents, and drug overdose. Among patients with trauma, the most frequently repoed surgical conditions in ARDS are pulmonary contusion, multiple bone fractures, and chest wall trauma/flail chest, whereas head trauma, near-drowning, toxic inhalation, and burns are rare causes. Ref Davidson edition23rd pg 606,199,170