An endotracheal tube (ET tube) is a tube that is inserted into the trachea (windpipe) to maintain an open airway and provide a route for administration of oxygen, anesthesia, and other medical treatments. The tube is usually inserted by a doctor or nurse in the operating room or emergency room. The tube is held in place with the help of a cuff that is inflated with air. The tube may also be secured with tape or sutures. The tube is connected to a ventilator or other breathing device to provide oxygen and to help the patient breathe.