What are the classification of embolism?

There are different types of embolism classified based on the embolic material:

1. Thromboembolism – embolism of thrombus or blood clot.

2. Fat embolism – embolism of fat droplets.

3. Air embolism (also known as a gas embolism) – embolism of air bubbles.

4. Septic embolism – embolism of pus containing bacteria.

5. Tissue embolism – embolism of small fragments of tissue.

6. Foreign body embolism – embolism of foreign materials such as talc and other small objects.

7. Amniotic fluid embolism – embolism of amniotic fluid, fetal cells, hair or other debris that enter the mother’s blood stream via the placental bed of the uterus and trigger an allergic reaction.

The pathway of the embolus can have 3 different types:

1. Anterograde.
2. Retrograde.
3. Paradoxical.
In anterograde embolism, we say that the movement of emboli is according to the direction of blood flow. However it is otherwise in retreograde embolism, when the weight of the emboli is high enough to oppose the blood flow direction. This is usually only siginificant in blood vessels with low pressure (veins) or emboli of high weight. In paradoxical embolism or also known as crossed embolism, the embolus from veins are crossed to the arterial blood system. This is usually only found in heart defects such as septal defects between the atria or ventricles.