Closed thoracic drainage is a minimally invasive surgical procedure often used in orthopaedic patients. It is used in patients with fluid or gas accumulation in the chest cavity, which most often occurs in patients with multiple rib fractures. In severe cases of rib fractures, the fracture end may puncture the pleura and even the lungs. In this case, closed chest drainage is required, and the drainage bottle is replaced by closing the internal chest drainage tube with a hemostat to prevent gas from being sucked into the chest cavity. After replacing the drainage bottle or the fluid in the bottle, the hemostatic forceps can then be opened. Closed chest drainage is to place the drainage tube inside the chest cavity and squeeze the fluid inside the chest cavity out of the chest cavity through the single extracorporeal channel of the drainage tube and the pressure generated inside the chest cavity through breathing and coughing to achieve the purpose of treatment. The two tubes that connect the chest drain to the hose used for venting are separate. The drainage tube is enclosed under the plane of fluid in the drainage bottle, while the venting tube is on the plane of fluid in the bottle, using the pressure of the fluid to resist the negative pressure of the chest cavity. Therefore, when replacing the drainage bottle, the drainage tube must be closed.