Chest tube insertion is a medical procedure used to remove air, fluid, or pus from the space around the lungs, known as the pleural space. This procedure is often necessary in cases of pneumothorax (collapsed lung) or pleural effusion (fluid buildup). A thin, flexible tube is inserted through the chest wall into the pleural space to allow for drainage. The procedure is typically performed under local anesthesia, and the patient may be positioned sitting up or lying down. After the tube is placed, it is connected to a drainage system to help maintain proper lung function and promote healing.