2. Introduction
Any trauma may complicate by 3 types of embolism according to its site & force
If trauma was associated by long Bone fractures it may complicate by fat embolism
If the neck or the thoracic cage were injured in the trauma it may complicate by
systemic air embolism due to injury to blood vessel or a heart chamber their pressure
is relatively negative
Commonly with violent traumas which are associated with bone fractures & inability
of walking for a while, Patients will have to lay in their beds in a certain position for
long time, this prolonged recumbency in bed may lead to deep vein thrombosis (DVT)
& if detachment occurs it may lead to pulmonary embolism
In this research we will spotlight on these 3 types
1- Fat embolism
Definition: A fat embolism is a type of embolism that is often (but not always) caused
by physical trauma
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 hematological (anemia, 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 of
the syndrome; however, it occurs in only 20-50% of cases.
The risk of fat embolism syndrome is thought to be reduced by early immobilization
of fractures, 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%
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.
3. 2- Air embolism
Definition: Small amounts of air often get into the blood circulation accidentally
following a trauma
Death may occur if a large bubble of gas becomes lodged in the heart; stopping blood
from flowing from the right ventricle to the lungs (this is similar to vapor lock in
engine fuel systems).
Pathogenesis: Air embolism can occur whenever a blood vessel is open and a
pressure gradient exists favoring entry of gas.
Because the pressure in most arteries and veins is greater than atmospheric pressure,
an air embolus does not always happen when a blood vessel is injured. In the veins
above the heart, such as in the head and neck, the pressure is less than atmospheric
and an injury may let air in. This is one reason why surgeons must be particularly
careful when operating on the brain, and why the head of the bed is tilted down when
inserting or removing a central venous catheter from the jugular or subclavian veins.
When air enters the veins, it travels to the right side of the heart, and then to the lungs.
This can cause the vessels of the lung to constrict, raising the pressure in the right side
of the heart. If the pressure rises high enough in a patient who is one of the 20% to
30% of the population with a patent foramen ovale, the gas bubble can then travel to
the left side of the heart, and on to the brain or coronary arteries. Such bubbles are
responsible for the most serious of gas embolic symptoms.
Trauma to the lung can also cause an air embolism. This may happen after a patient is
placed on a ventilator and air is forced into an injured vein or artery, causing sudden
death.
N.B: Pulmonary barotrauma in divers: Air bubbles enter the bloodstream as a result
of gross trauma to the lining of the lung following a rapid ascent while holding the
breath; the air held within the lung expands to the point where the lungs burst
(pulmonary barotrauma). This is easy to do as the lungs give little warning through
pain until they do burst. The diver will arrive at the surface in pain and distress and
may froth or spit blood
Treatment: Recompression is the most effective treatment of an air
embolism. Normally this is carried out in a recompression chamber.
It is also important to promptly place the patient in left lateral decubitus position this
positioning helps to trap air in the apex of the ventricle and prevent it from reaching
the lung circulation.
4. 3-Pulmonary embolism
Risk factors: The most common sources of embolism are proximal leg deep venous
thrombosis (DVTs) or pelvic vein thrombosis. Any risk factor for DVT also increases
the risk that the venous clot will dislodge and migrate to the lung circulation, which
happens in up to 15% of all DVTs. The conditions are generally regarded as a
continuum termed venous thromboembolism (VTE). Due to prolonged recumbency in
bed following a trauma
Mortality: from untreated PE is said to be 26%
Diagnosis: The diagnosis of PE is based primarily on validated clinical criteria
combined with selective testing as:
Blood tests
Imaging
Electrocardiogram
Echocardiography
Algorithms
Treatment:
Anticoagulation
Thrombolysis
Surgery
Inferior vena cava filter
