Hemothorax, if severe enough, can lead to hemorrhagic shock. Therefore, timely diagnosis and treatment are paramount. After a chest tube is placed, if drainage of blood is greater than 1.5 L or one-third of blood volume, or if drainage is greater than 200 mL/h for over 2 to 4 hours, a thoracotomy is indicated. Alternatively, if the patient is older than 60 years and drainage is greater than 100 mL/h for over 4 hours, a thoracotomy is also indicated. If the patient does not meet these criteria but is still hemodynamically unstable or if ventilation is difficult, emergent surgery should be performed.