What Causes Fat Embolism Syndrome?

Severe Burns

Individuals who experience severe burns on a large portion of their skin area can develop fat embolism syndrome. This pathophysiology is the result of both mechanical factors and biochemical processes. The skin is made up of several layers. The outermost layer is called the epidermis and provides a waterproof barrier between underlying tissues and external elements. The next layer, called the dermis, is packed full of nerves and blood vessels that supply sensation and blood to the skin. The layer below the dermis is called the fat layer or subcutaneous tissue, which stores fat, protects underlying tissues from exaggerated temperature changes, and produces certain hormones. The subcutaneous layer has blood vessels within it that are slightly larger than those found in the dermis.

Extreme heat can scald away the epidermis, all or part of the dermis, and penetrate the subcutaneous layer. This type of injury causes blood vessels in the affected regions of the skin to be vaporized, severed, and or severely damaged. When the burn has penetrated the subcutaneous layer and damages lipid storing cells, micro fragments of fat are allowed to mobilize into the venous bloodstream. Inflammatory processes cause the fragments to materialize further and become lodged in the lungs, producing symptoms of fat embolism syndrome.