Crepitus; Subcutaneous air; Tissue emphysema; Surgical emphysema
Subcutaneous (under the skin) emphysema occurs when air gets into tissues under the skin. This most often occurs in the skin covering the chest or neck, but can also occur in other parts of the body.
Subcutaneous emphysema can often be seen as a smooth bulging of the skin. When a health care provider feels (palpates) the skin, it produces an unusual crackling sensation (crepitus) as the gas is pushed through the tissue.
This is a rare condition. When it does occur, possible causes include:
This condition can happen due to:
Air can also be found in between skin layers on the arms and legs or torso after certain infections, including gas gangrene, or after scuba diving. (Scuba divers with asthma are more likely to have this problem than other scuba divers.)
Most of the conditions that cause subcutaneous emphysema are severe, and you are likely already being treated by a provider. Sometimes a hospital stay is needed. This is more likely if the problem is due to an infection.
If you feel subcutaneous air in relation to any of the situations described above, particularly after trauma, call 911 or the local emergency services number immediately.
Do not administer any fluids. Do not move the person unless it is absolutely necessary to remove them from a hazardous environment. Protect the neck and back from further injury when doing so.
The provider will measure and monitor the person's vital signs, including:
Symptoms will be treated as needed. The person may receive:
The prognosis depends on the cause of the subcutaneous emphysema. If associated with major trauma, a procedure or infection, the severity of those conditions will determine the outcome.
Subcutaneous emphysema associated with scuba diving is most often less serious.
Davis AS, Mohr NM. Pleural disease. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 63.
Lenz RJ, Loyd JE. Mediastinitis and fibrosing mediastinitis. In: Broaddus VC, Ernst JD, King TE, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 7th ed. Philadelphia, PA: Elsevier; 2022:chap 116.
Peak DA. Scuba diving and dysbarism. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 131.
Raja AS. Thoracic trauma. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 37.BACK TO TOP
Review Date: 7/6/2022
Reviewed By: Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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