An increase in urban violence combined with better prehospital and transport systems has resulted in the arrival of sicker trauma patients to the Emergency Department (ED). Previously, these patients might not have survived long enough to make it to the ED.1 The majority of individuals with penetrating chest injuries arrive at the ED in stable condition and are managed without major operative procedures.2 A subset of individuals, however, arrive in extremis and may require a thoracotomy. The purpose of the ED thoracotomy may be to control hemorrhage within the chest or below, to relieve a pericardial tamponade, to redistribute cardiac output to the brain and the heart, or to provide more effective cardiac massage.3
ANATOMY AND PATHOPHYSIOLOGY
The structures within the chest include the heart, esophagus, lungs, bronchi, pulmonary hilar vessels, and numerous other vascular structures. The heart is located in the anterior mediastinum. The aorta and esophagus are located in the posterior mediastinum. The internal mammary arteries course along the posterior aspect of the anterior chest wall just lateral to the sternum. The intercostal vessels run along the inferior aspect of the ribs. The subclavian vessels are at the very superior aspect of the thorax. They course directly under the clavicles and can be very difficult to visualize via an anterolateral thoracotomy. The azygos vein can be found coursing along the posterior right hemithorax and empties into the superior vena cava.
The heart is covered by the tough pericardial sac. The phrenic nerves run superiorly and inferiorly on each side of the pericardiac sac. They can be visualized as white or yellow strands on either side of the pericardium. Once the pericardial sac is opened, the left anterior descending coronary artery can be visualized on the anterior surface of the heart. It overlies the interventricular septum. Injuries to the left of this artery usually denote left ventricular damage, whereas injuries to the right usually denote right ventricular damage. The majority of the anterior surface of the heart is occupied by the right ventricle.
The posterior mediastinum contains the aorta. It is located posterior to the esophagus and runs lateral to the vertebral bodies. The thoracic aorta gives off the intercostal vessels. If torn during the mobilization of the aorta, the intercostal vessels can cause troublesome bleeding.
The ED thoracotomy was originally introduced for penetrating chest wounds.4 This procedure was subsequently used for patients with penetrating abdominal wounds and victims of blunt trauma. In recent years, several studies have shown an abysmal survival rate associated with an ED thoracotomy in victims of blunt trauma, including children.5,6 When vital signs are present in the field, the survival rates for such individuals range from 0.6% to 6.0%.7-12 Patients who undergo an ED thoracotomy for penetrating abdominal injuries have survival rates of approximately 5%.11,13 In these cases, ...