Fat embolism

Thromboembolism or fat embolism, thrombophlebitis, necrotizing angiitis, syncopal episodes, cardiac arrhythmias, aggravation of hypertension... 

Extracorporeal circulation Extracorporeal membrane oxygenation Fat embolism Heat stroke... 

Most lipids are barely soluble in water, and many have amphipathic properties. In the blood, free triacylglycerols would coalesce into drops that could cause fat embolisms. By contrast, amphipathic lipids would be deposited in the blood cells membranes and would dissolve them. Special precautions are therefore needed for lipid transport in the blood. While long-chain fatty acids are bound to albumin and short-chain ones are dissolved in the plasma (see p. 276), other lipids are transported in lipoprotein complexes, of which there several types in the blood plasma, with different sizes and composition. 

The use of acetazolamide in the presence of unrecognized cerebral edema due to fat embolism, with sudden normalization of brain C02, as occurred in this patient when her previous state of hypocapnia was no longer sustained by ventilatory effort, resulted in cerebral acidosis, vasodilatation, and a further increase in intracranial pressure. This proved catastrophic and led to brainstem herniation and brain death. Acetazolamide should be avoided if at all possible in patients with bony and traumatic brain injuries, particularly during weaning from mechanical ventilation, since it can precipitate coning in patients with raised intracranial pressure. 

Walshe CM, Cooper JD, Kossmann T, Hayes I, lies L. Cerebral fat embolism syndrome causing brain death after long-bone fractures and acetazolamdie therapy. Crit Care Resusc 2007 9 184-6. 

Chronic meningitis nflammatory bowel disease Mitochondrial disease Fabry s disease Homocystinemia Hypoglycemia/hypercalcemia Fat embolism... 

Fat embolism, which usually occurs following long bone fracture or surgery, most commonly causes a global encephalopathy, but on occasion there may be focal features, presumably reflecting local ischemia (Jacobson et al. 1986 van Oostenbrugge et al. 1996). 

Jacobson DM, Terrence CF, Reinmuth OM (1986). The neurological manifestations of fat embolism. Neurology 36 847-851... 

Fatal stroke due to paradoxical fat embolism. Cerebrovascular Diseases 6 313-314... 

Atypical antipsychotic drugs Chronic subdural hematoma (Ch. 7) Vertebral/carotid artery dissection (Ch. 6) Fat embolism (Ch. 6) nternal carotid artery stenosis (distal) Dural arteriovenous fistula (Ch. 7)... 

In cases of severe fatty liver, there is indeed a risk of fat embolism occurring in the lungs, brain and kidneys. In view of the considerable fat masses stored in the hepatic parenchyma due to this condition, R. Virchow suspected the manifestation of fat embolism as early as 1886. (s. tab. 31.9) Blunt traumatism of the (enlarged) liver with subsequent mobilization of fat is thought to be the cause of this condition. It is not clear at present whether this so-called inundation theory offers sufficient explanation or whether it needs to be amended or even replaced by the so-called segregation theory (high lipaemia, deemulsification of blood fats, etc.). While hepatic fat embolism may be rare, it is nevertheless clinically relevant. 

Fat embolism is a rare complication of intra-osseous phlebography (280,281). 

Thomas ML, Tighe JR. Death from fat embolism as a complication of intraosseous phlebography. Lancet 1973 2(7843) 1415-6. 

Goulon M, Barois A, Grosbuis S, Schortgen G. Fat embolism after repeated perfusion of lipid emulsion. Nouv Presse Med 1974 3 13-18. 

Soybean oil is widely used intramuscularly as a drug vehicle or as a component of emulsions used in parenteral nutrition regimens it is also consumed as an edible oil. Generally, soybean oil is regarded as an essentially nontoxic and nonirritant material. However, serious adverse reactions to soybean oil emulsions administered parenterally have been reported. These include cases of hypersensitivity, CNS reactions, " and fat embolism. " Interference with the anticoagulant effect of warfarin has also been reported. ... 

Estebe JP, Malledant Y. Fat embolism after lipid emulsion infusion [letter]. Lancet 1991 337 673. 

Cause Exact cause remains unknown but pulmonary sickling resulting in infraction is the key element. Proposed etiologies include infectious (S. pneumoniae, H. influenzae. Chlamydia, Mycoplasma, and viral) and noninfectious (fat embolization from bone infarction, hypoventilation... 

It is very obvious that many of the consequences of injury imperil, or are potentially capable of imperiling, survival apart altogether from the purely local damage done. Such are hemorrhage, renal failure, or cerebral fat embolism but many, such as those concerned with preservation of homeostasis are defense mechanisms, e.g., the vasoconstriction of skin and muscle which reduces bleeding, and hemodilution which helps to offset blood loss. 

Sevitt has suggested that traumatic lipemia with rise in free fatty acids in particular, and less markedly of cholesterol, neutral fat, and phospholipids, may be considered as part of the general metabolic response to injury. Pulmonary fat embolism is found at necropsy in 90-100% of patients who have died shortly after fracture—possibly a protective trapping mechanism in that few fat emboli will reach the systemic circulation. 

P3. Peltier, L. F., Fat embolism. The failure of lipaemia to potentiate the degree of fat embolism accompanying fractures of the femur in rabbits. Surgery 38, 720-722 (1955). 

The earliest recorded experiments were carried out in England by Courten in 1679 (24). He injected a dog intravenously half an ounce of olive oil that had not been emuIsitied. The re.sult was that the dog died of a fat embolism. At the end of the nineteenth century experiments were carried out giving campber oi) subcutaneously to patients with spinal tuberculosis. At this time attempts were once again made to administer fat intravenously (63,157,162). However, these preparations could not be used clinically. 

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