The most common source of pulmonary embolism is?
Ans. is `c' i.e., Large veins of lower limb Pulmonary embolism Pulmonary embolism is a blockage of pulmonary aery or one of its branches. o Pulmonary embolism is an extremely common and highly lethal condition that is leading cause of death in all age groups. Etiology o In more than 95% of instances, venous emboli originating from deep leg vein thrombi above the level of knee i.e. in popletial, femoral or iliac veins. o Although most common site of deep vein thrombosis is calf veins, calf veins thrombosis are itself associated with a low risk of embolism, but when the thrombosis progresses proximally to involve the larger veins above the leg then the risk becomes very high. o So, Most common site of DVT Calf veins Most common source of pulmonary embolism --)DVT of proximal veins of lower limb i.e., popliteal, femoral or iliac veins. Pathophysiology of pulmonary embolism o If the size of embolus is large, it may be impacted at the bifurcation of main pulmonary aery --> Saddle embolus, or may be passed out into the smaller, branching aerioles. o More commonly, there are multiple emboli, or a large embolus may be fragmented into many smaller emboli which are then impacted in a number of vessels, paicularly affecting the lower lobes of lungs. o Rarely, Paradoxical embolism may occur by passage of an embolus from right side of hea into the left hea through ASD or VSD. In this way, pulmonary emboli may reach systemic circulation.
Amniotic fluid embolism
Renal aery embolism
Large veins of lower limb
Cardiothoracic surgery