<unk> es are classified in three broad categories according to the cause and in order of frequency: traumatic, iatrogenic, or nontraumatic. All three categories have the potential to affect major arteries and result in death by blood loss. Traumatic<unk>  is most often caused by blunt or penetrating trauma to the chest. In blunt traumatic cases,<unk>  typically occurs when rib fracture damages the intercostal vessels or the intraparenchymal pulmonary vessel, while in penetrating trauma,<unk>  occurs due to injuries directly affecting blood vessels in the thoracic wall, lung parenchyma, or the heart. If large blood vessels such as the aorta are damaged, the blood loss can be massive. Minor chest trauma can cause<unk>  when the blood's ability to clot is diminished as result either of anticoagulant medications or when there are bleeding disorders such as hemophilia. Iatrogenic Iatrogenic<unk>  can occur as a complication of heart and lung surgery, for example the rupture of lung arteries caused by the placement of catheters, thoracotomy, thoracostomy, or thoracentesis. The most common iatrogenic causes include subclavian venous catheterizations and chest tube placements, with an occurrence rate of around 1% Sometimes, a Swan-Ganz catheter causes rupture of the pulmonary artery, causing a massive<unk> . It can also be caused by other procedures like pleural, lung, or transbronchial biopsies, CPR, Nuss procedure, or endoscopic treatment of esophageal varices. Iatrogenic<unk>  is more common in people who have chronic kidney disease in the intensive care unit. Nontraumatic Less frequently,<unk> es may occur spontaneously. Nontraumatic<unk> es most frequently occur as a complication of some forms of cancer if the tumour invades the pleural space. Cancers responsible for<unk> es include angiosarcomas, schwannomas, mesothelioma, thymomas, germ cell tumours, and lung cancer. Significant<unk> es can occur with spontaneous rupture of small vessels when the blood's ability to clot is diminished as result of anticoagulant medications. In cases caused by anticoagulant therapy, the<unk>  becomes noticeable 4–7 days after anticoagulant therapy is started. In cases of<unk>  complicating pulmonary embolism treatment, the<unk>  is usually on the side of the original embolism. Those with an abnormal accumulation of air within the pleural space (a pneumothorax) can bleed into the cavity, which occurs in about 5% of cases of spontaneous pneumothorax, especially when lung bullae rupture. The resulting combination of air and blood within the pleural space is known as a hemopneumothorax. Bone growth in exostosis can create sharp edges, which can result in<unk>  by damaging adjacent arteries. It can occur postpartum due to the change in thoracic pressure during labor. Vascular Vascular causes of<unk>  include rupture of the descending aorta, in which case it initially involves the left pleural and mediastinal area due to the close vicinity of the pleural cavity. Rarely, a rupture of the thoracic aorta can result in a<unk> , but the bleeding usually occurs in the pericardial space. Spontaneous tearing of blood vessels is more likely to occur in those with disorders that weaken blood vessels such as some forms of Ehlers-Danlos syndrome, disorders that lead to malformed blood vessels as seen in Rendu-Osler-Weber syndrome, or in bleeding disorders such as hemophilia and Glanzmann thromboastenia. Other rare causes of<unk>  include neurofibromatosis type 1 and extramedullary hematopoiesis. Catamenial Rarely,<unk> es can arise due to extrapelvic endometriosis, a condition in which tissue similar to the lining that normally covers the inside of the uterus forms in unusual locations outside the pelvis. Endometriotic tissue that implants on the pleural surface can bleed in response to the hormonal changes of the menstrual cycle, causing what is known as a catamenial<unk>  as part of thoracic endometriosis along with catamenial pneumothorax, catamenial hemoptysis, and lung nodules of endometriosis. Catamenial<unk>  represents 14% of cases of thoracic endometriosis syndrome while catamenial pneumothorax is seen in 73%, catamenial hemoptysis in 7%, and pulmonary nodules in 6%.
Hemothorax
Pneumothorax
Urinothorax
Traumatic cardiac arrest
Chylothorax
Pulmonary hematoma
Hydropneumothorax
Hemopneumothorax