Fat embolism syndrome

Fat embolism syndrome
Specialty	Emergency medicine

A fat embolism is a type of embolism that is often (but not always) caused by physical trauma like fracture of long bones, soft tissue trauma and burns.

Presentation

Unlike emboli that arise from thrombi (blood clots), fat emboli are small and multiple, and so have widespread effects.

Fat embolism syndrome (FES) is distinct from the presence of fat emboli. Symptoms usually occur 1-3 days after a traumatic injury and are predominantly pulmonary (shortness of breath, hypoxemia), neurological (agitation, delirium, or coma), dermatological (petechial rash), and haematological (anaemia, low platelets). The syndrome manifests more frequently in closed fractures of the pelvis or long bones. The petechial rash, which usually resolves in 5-7 days is said to be pathognomonic for the syndrome, but only occurs in 20-50% of cases.

Fat emboli occur in almost 90% of all patients with severe injuries to bones, although only 10% of these are symptomatic. The risk of fat embolism syndrome is thought to be reduced by early immobilization of fractures and especially by early operative correction. There is also some evidence that steroid prophylaxis of high-risk patients reduces the incidence. The mortality rate of fat-embolism syndrome is approximately 10-20%.

Pathogenesis

The pathogenesis occurs due to both mechanical obstruction and biochemical injury. The microemboli cause pulmonary and cerebral microvasculature occlusion. It is aggravated by local platelet and erythrocyte aggregation. The release of free fatty acids from the fat globules causes local toxic injury to endothelium. The vascular damage is aggravated by platelet activation and recruitment of granulocytes.

Treatment

The most effective prophylactic measure is to reduce long bone fractures as soon as possible after the injury.

Maintenance of intravascular volume is important because shock can exacerbate the lung injury caused by FES. Albumin has been recommended for volume resuscitation in addition to balanced electrolyte solution, because it not only restores blood volume but also binds fatty acids, and may decrease the extent of lung injury.

See also

• Air embolism
• Cholesterol embolism
• Pulmonary embolism
• CT pulmonary angiogram

External links

• . GPnotebook https://www.gpnotebook.co.uk/simplepage.cfm?ID=973471750. {{cite web}}: Missing or empty |title= (help)
• Fat embolism syndrome at the Duke University Health System's Orthopedics program

• Fat Embolism MRI Brain Injury from Fat Embolism