pulmonary disorders
Atelectasis
Key Points
Atelectasis is reversible collapse of lung tissue with loss of volume; common causes include intrinsic or extrinsic airway compression, hypoventilation, and a malpositioned endotracheal tube. A large area of atelectasis may cause symptomatic hypoxemia, but any other symptoms are due to the cause or a superimposed pneumonia. Diagnosis is by chest x-ray; if the cause is not clinically apparent, bronchoscopy or chest computed tomography may be needed. Treatment involves maximizing coughing, deep breathing, and, whenever possible, walking. 