What department is pneumothorax treated in? For pneumothorax, we commonly see patients first in the emergency department, as the onset of pneumothorax is generally very sudden and the condition can be quite severe. The patient may suddenly experience difficulty breathing, and in most cases, this breathing difficulty is severe. Therefore, patients typically start by seeing the emergency internal medicine department. The doctors there will assess the patient’s condition and will consult with thoracic and cardiovascular surgery and respiratory medicine. If a closed thoracic drainage tube is needed, our surgeons will immediately perform the drainage. If the patient can be treated conservatively, they are usually then transferred to either respiratory medicine or thoracic and cardiovascular surgery for further treatment.