A chest seal is a specialized first-aid dressing designed to treat specific chest injuries by acting as a barrier over a wound to manage air movement. It functions as a temporary measure in emergency trauma care when the chest wall has been compromised. These seals are found in many first aid kits and can be used by trained individuals to address life-threatening situations until professional medical help arrives.
Identifying a Chest Injury
A chest seal is used for a penetrating chest injury, often called a “sucking chest wound” or open pneumothorax. This occurs when an open wound in the chest wall allows outside air to enter the pleural cavity, the space between the lung and the chest wall. Common causes include stab wounds, gunshot wounds, impalement, or severe blunt trauma that creates an open defect.
Visible signs indicate a penetrating chest injury. There may be an obvious open wound on the chest, which can be about the size of a coin or larger. A telltale sign is bubbling blood or frothy discharge around the wound, accompanied by a distinct hissing or sucking sound as the injured person breathes.
The injured person may also exhibit symptoms due to compromised breathing. These include difficulty breathing, shortness of breath, rapid and shallow breathing, chest pain, anxiety, and a rapid heart rate.
Other signs can include a crackling sound or sensation under the skin around the wound, known as subcutaneous emphysema, or a bluish tint to the lips or fingers due to oxygen deprivation. Recognizing these indicators promptly allows for effective intervention.
How a Chest Seal Works
A chest seal creates an airtight barrier over a penetrating chest wound, which is important for managing altered pressure within the chest cavity. Normally, the chest cavity operates as a closed system, allowing the lungs to expand and contract with each breath. When a hole is created in the chest wall, this closed system is disrupted, allowing air to enter the space around the lung.
The primary purpose of a chest seal is to prevent outside air from entering the pleural space, maintaining the proper pressure balance necessary for lung function. This is important in preventing or managing a life-threatening condition called tension pneumothorax. In a tension pneumothorax, air accumulates in the chest cavity, pressing on the lung and potentially shifting the heart and major blood vessels, which can severely impair breathing and circulation.
Some chest seals have vents, featuring a one-way valve that allows trapped air to escape during exhalation, while preventing outside air from entering. This vented design can reduce the risk of a tension pneumothorax if air continues to leak from the injured lung. Unvented seals, while simpler, require vigilant monitoring. If air continues to accumulate, it can lead to increased pressure and may require lifting an edge of the seal to release trapped air. Sealing the wound helps stabilize the casualty’s breathing and prevents further deterioration of their respiratory status.
Using a Chest Seal and Next Steps
When encountering a suspected penetrating chest injury, the immediate action is to contact emergency medical services (EMS) without delay. While waiting for professional help, a chest seal can be applied as a temporary measure. Application involves first exposing the wound by removing clothing and then wiping away blood or debris to ensure the seal adheres properly to the skin. The chest seal is then applied directly over the wound, ensuring a tight seal around its edges. If there are multiple wounds, such as an entrance and exit wound from a gunshot, both must be sealed.
After applying the chest seal, continuously monitor the injured person’s breathing, level of consciousness, and overall condition. The chest seal is not a definitive treatment but a temporary intervention to stabilize the casualty until they receive professional medical care. Rapid transport to a medical facility is important for complete evaluation and treatment of the underlying injury. If the person’s breathing worsens after the seal is applied, it may be necessary to briefly lift one edge of the seal to allow trapped air to escape, a process sometimes called “burping” the seal, before reapplying it.