The fat embolism syndrome (FES) is associated with fat particles in the microcirculation of the lung.

It consists typically of lung dysfunction, neurologic manifestations, and petechiae, usually following a latent interval.

[delay is thought to result from the evolving effects of vasoactive substances in the lung and the resulting decrement in gas exchange.]


It is most common following long bone fractures, typically presenting as dyspnea and confusion.1 After long bone or pelvic fracture, the incidence of the syndrome is at least 10% when patients are prospectively screened, although serious clinical manifestations are seen in only 1% to 3%. Since the clinical presentation is usually mild, FES is often unrecognized. Even when lung injury is obvious, its cause may be attributed to infection, aspiration, or traumatic ARDS, rather than to fat embolization.

FES has been proposed as a major cause of the acute chest syndrome in patients with sickle cell disease following often unregulated cosmetic procedures involving silicone or mineral oil injection.1


Causes of Fat Embolism Syndrome

Traumatic Fat Embolism Nontraumatic Fat Embolism
Long bone fracture (especially femur) Pancreatitis Fatty liver of pregnancy
Other fractures Diabetes mellitus Cardiopulmonary bypass
Orthopedic surgery Lipid infusions
Blunt trauma to fatty organs (liver) Sickle cell crisis Decompression sickness
Liposuction Burns Corticosteroid therapy
Bone marrow biopsy Osteomyelitis Lymphangiography




No specific treatment exists for FES.

supportive pulmonary care, often with intubation, oxygen, and mechanical ventilation with airway pressure support in an effort to mitigate the effects of the adult respiratory distress syndrome.

In many circumstances high-dose steroids are empirically utilized as a general measure to blunt the lung reaction, stabilize the pulmonary capillary bed, and improve gas exchange.supportive therapy.


Fat embolism syndrome (FES) is a rare syndrome.


Complications of Injecting Drug Use

  • Local problems—Abscess (Figures 240-2 
    Image not available.

    A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of ­Richard P. Usatine, MD.)

    and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
    • IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
    • Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
  • IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
    • Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.


While this constellation of findings is uncommon, the mortality rate approaches 10% to 15% after full-blown FES. A high index of suspicion is necessary for early diagnosis and proper treatment.

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