Fat embolism

A fat embolism is a type of embolism that is often caused by physical trauma such as fracture of long bones, soft tissue trauma, and burns.

Signs and symptoms

An asymptomatic latent period of about 12–48 hours precedes the clinical signs and symptoms. The severe form presents as acute cor pulmonale, respiratory failure. This may lead to death within a few hours of injury.

Clinical fat embolism syndrome presents with tachycardia, tachypnea, elevated temperature, hypoxemia, hypercapnia, thrombocytopenia, and occasionally mild neurological symptoms.

A petechial rash that appears on the upper anterior portion of the body, including the chest, neck, upper arm, axilla, shoulder, oral mucosa and conjunctivae is considered to be a pathognomonic sign of FES, however, it appears late and often disappears within hours. It results from occlusion of dermal capillaries by fat, and increased capillary fragility.

Central nervous system (CNS) signs, including a change in level of consciousness, are not uncommon. They are usually nonspecific and have the features of diffuse encephalopathy: acute confusion, stupor, coma, rigidity (neurology), or convulsions. Cerebral edema contributes to the neurologic deterioration.