Fat embolism
A fat embolism is a embolism occurring in the bloodstream fat droplets. These occur either as released Gewebsfette and / or as precipitated plasma fats, eg after a fracture with bone marrow involvement, while large orthopedic procedures such as implantation of endoprostheses in large joints, amputations, soft tissue contusion, combustion, power injury or injection of oil-containing preparations in the bloodstream.
Disease
The clinical picture corresponds to an acute pulmonary embolism with respiratory failure, right heart failure and heart rhythm disturbances up to acute cardiovascular arrest may occur to minutes after the damaging event the seconds. Delayed ( within 36 -72h ) there may be point-like bruising ( petechiae ), coagulation disorders come through to consumption coagulopathy and impaired consciousness caused by cerebral Mikroinfarzierung. This disease is known as fat embolism syndrome.
Pathogenesis
As a cause of acute fat embolism, especially an increase in pressure in the medullary cavity is assumed to be trespassing of fat and bone marrow cells into the bloodstream. This leads to a microembolization small pulmonary vessels with increase in pressure in the pulmonary circulation. As a cause of fat embolism syndrome the reduction of fat particles laid down in the pulmonary capillaries is assumed to toxic fatty acids. These pathological mechanisms could be confirmed in animal experiments.
Therapy
The treatment consists first of a generous supply of oxygen and careful volume replacement under the control of pulmonar arterial pressure ( right heart catheterization ), catecholamines and resuscitation if necessary. This is followed by the usual intensive medical therapy.
The fat embolism syndrome is primarily symptomatic treatment (correction of coagulopathy, fluid balance and security of kidney function).
Fat embolism as a complication of orthopedic / surgical operations accident
Rarely, but often compared to all other causes fat embolism occur in the context of accident- surgical and orthopedic operations. In particular, this concerns the marrow nailing, the implantation of endoprostheses of the hip or knee joint as well as vertebroplasty. The critical point here is the driving of the intramedullary nail or prosthesis stem component into the medullary canal of the femur (thigh bone). The main cause of increased pressure on the bone marrow is assumed, associated with the heating in the setting phase of the bone cement, and possibly a transgression of constituents of bone cement ( methyl methacrylate ) in the bloodstream.
The frequency (incidence) of fat embolism in implantation of hip prostheses is given as 0.6 % -10 %, the fatal outcome ( mortality ) with 0.2 % -0.6 %.
For the prophylaxis of fat embolism a number of different measures have been proposed ( washout of the medullary cavity, relief well Vakuumzementierung, blood blockage and others). Enforced has been, for lack of evidence, none of these measures.
Swell
- Aebli N., R. Pitto, J. Cancer: Fat embolism - a potentially fatal complication during orthopedic surgery; Switzerland Med Forum 2005; 5:512-518, S. 512 (pdf file )
- Disease in angiology
- Disease in orthopedic and trauma surgery
- Disease in gynecology and obstetrics