Fat embolism occurs when fat globules enter the bloodstream and become lodged in small blood vessels, potentially causing respiratory distress, neurological abnormalities, and a rash. It typically develops 1-3 days following long bone fractures or other trauma. The document discusses the pathophysiology, clinical presentation including respiratory changes, neurological features and petechial rash, diagnosis criteria, and management approaches such as immobilization, ventilation, fluid resuscitation, and in some cases prophylactic corticosteroids or ethanol administration.

1. Fat Embolism
Gladson M. Robin

2. Definition
Fat embolism indicates the often
asymptomatic presence of fat
globules in the lung parenchyma
and peripheral circulation.
Symptomatic – Fat Embolism Syndrome (FES)

4. Pathophysiology
2 major theories
Drawback:
Does not explain the delay
in onset (24-72 hrs)

5. Pathophysiology
Etiology
Hydrolysis/Degradation
Free fatty acids/
Other chemical mediators
Lung injury / Agglutination of fat
globules...
Clinical Manifestations

6.  Presents within 24 – 72 hrs
 Rarely <12 hrs or >2 weeks
 Classical triad:
 Respiratory changes
 Neurological abnormalities
 Petechial rash
Paradoxical embolism

7. Respiratory changes
 First clinical feature
 Frequent findings: Dyspnoea, Tachypnoea, Hypoxaemia
 Syndrome indistinguishable from ARDS may develop due to alveolar hemorrhage
 50% require mechanical ventilation
Clinical Presentation…

8. Neurological features
 86% of them with cerebral emboli manifest neurological signs after respiratory
distress
 Mild confusion and drowsiness  severe seizures
 Common clinical state: Acute confusional state
 All neurological symptoms are transient and fully reversible
Clinical Presentation…

9. Petechial rash
 60% of cases
 Due to embolization of small dermal capillaries  Extravasation of erythrocytes
 Conjunctiva, Oral mucosa, Skin folds of upper body
 Platelets Normal
 Rash appears within 36 hrs, disappears within 7 days (self limiting)
Clinical Presentation…

10. Petechial rash
 60% of cases
 Due to embolization of small dermal capillaries  Extravasation of erythrocytes
 Conjunctiva, Oral mucosa, Skin folds of upper body
 Platelets Normal
 Rash appears within 36 hrs, disappears within 7 days (self limiting)
Clinical Presentation…

11. Minor features
due to release of toxic mediators
 Pyrexia
 Tachycardia
 Myocardial depression
 ECG changes due to right heart strain
 Soft fluffy retinal exudates with macular edema scotomata
 Coagulation abnormalities
 Renal Changes (Oliguria, Lipiduria, Proteinuria, Hematuria)
Clinical Presentation…

12. Diagnosis
 Diagnosis usually by clinical finings
 Biochemical values may be helpful
 Criteria for diagnosis:
 Gurd’s criteria (commonly used)
 Lindeque’s criteria
 Schonfeld’s criteria
Gurd’s criteria: Atleast 1 major + 4 minor criteria  FES

13.  Unexplained Anaemia (70%)
 Unexplained Thrombocytopenia (<1,50,000 in 50%)
 Hypocalcaemia due to binding of calcium with free fatty acids
 Radiology – No significant help for diagnosis. Can be used as support
Diagnosis

14. Management
 Mortality: 10% - !5%
 Immobilization of fracture site
 Early definitive reduction of fracture (Open or Closed)
 Maintain intravascular volume to maintain cardiovascular stability (hypovolemic shock
resuscitation), may use colloids (albumin) as it can expand fluid and bind FFA.
 Mechanical ventilation with PEEP
 Corticosteroid as prophylactic (controversial)
 IV Ethanol as prophylactic in Russia, Europe & some American countries
 “A raised level of alcohol in the blood was associated with a lower incidence of fat
embolism” - J Bone Joint Surg Am. 1977 Oct;59(7):878-80
 Corticosteroids and Ethanol is of no use after onset of FES