Traumatic cardiac arrest (TCA) is a condition in which the heart has ceased to beat due to blunt or penetrating trauma, such as a stab wound to the thoracic area. It is a medical emergency which will always result in death without prompt advanced medical care. Even with prompt medical intervention, survival without neurological complications is rare. In recent years, protocols have been proposed to improve survival rate in patients with traumatic cardiac arrest, though the variable causes of this condition as well as many coexisting injuries can make these protocols difficult to standardize.
Tension pneumothorax
Tension pneumothorax is caused when air is able to enter the space between the lung and the chest wall, but is not able to escape. The increasing pressure within the chest cavity prevents blood from returning from the body to fill the heart.
Hemothorax
Hemothorax occurs when injury to the chest results in bleeding into the thoracic cavity. Similar to tension pneumothorax, increasing pressure prevents the return of blood from circulation to the heart.
Cardiac tamponade
In the setting of trauma, cardiac tamponade results from an acute pericardial effusion, the accumulation of blood within the sac that surrounds the heart. As this sac is filled with fluid, the pressure on the heart is increased, and the chambers of the heart are unable to fill with blood.
Hypoxia
Inability to maintain oxygenation in trauma patients may be a result of airway compromise due to mechanical injury or obstruction or due to loss of the respiratory drive from cervical spine or peripheral nerve injury. As clinicians begin to intervene, they will simultaneously seek reversible causes of the arrest. Management begins by establishing multiple points of IV access and evaluating the patient's airway and breathing. Other interventions may include thoracostomy and thoracotomy, as well as treatment of the underlying cause of arrest.
Basic life support
Basic life support is commonly initiated by bystanders and first responders, but the role of basic life support in traumatic cardiac arrest is unclear. Basic life support is targeted to maintain oxygenation and circulation throughout the body, which can be lifesaving in cases of medical cardiac arrest, but does not address the frequent large volume blood loss encounters in many cases of traumatic cardiac arrest. Evolving algorithms are directed at quickly identifying incidences of cardiac arrest with a traumatic source and rapidly intervening to address reversible causes. There is wide variability in the estimated survival rate based on factors that include initiation of pre-hospital care and nature of injury.
Many patients who survive traumatic cardiac arrest may develop long-term neurological damage resulting from lack of circulation to the nervous system during the arrest. This damage may range from moderate disability to a persistent vegetative state. A 2012 review suggests that while survival rates of traumatic cardiac arrest are higher in children, so is the incidence of neurological complication.