An endotracheal tube is a medical device used to maintain an open airway in patients who are unable to breathe on their own. It is a flexible tube inserted through the mouth or nose and into the trachea, allowing for mechanical ventilation and the delivery of oxygen. This procedure is often performed in emergency situations or during surgeries. Endotracheal tubes come in various sizes and are typically made of plastic. They are secured in place to prevent movement and are connected to a ventilator to assist with breathing. Proper placement is crucial to ensure that air reaches the lungs effectively.