The common causes of a shunt include pneumonia and pulmonary edema, tissue trauma, atelectasis, mucus plugging, pulmonary arteriovenous fistulas, etc. Moreover, lung disease always results in shunt. However, this can put enormous pressure on the right ventricle, leading to right ventricular dilation, which may even cause death. When the whole lung becomes hypoxic, it also can undergo vasoconstriction. Thus, the persistence of hypoxemia despite 100% oxygen inhalation refers to the shunt.įurthermore, the capillaries which surround the alveoli without proper ventilation undergo constriction as they make the returning vessels hypoxic. However, this mixing lowers the total oxygen content of the arterial blood, which moves out from the heart. Moreover, this poorly oxygenated blood subsequently returns to the heart and mixes up with the oxygenated blood, which comes from the other areas of the lungs with proper ventilation. Therefore, it decreases the oxygenation of the deoxygenated blood, which passes to the lungs. In the capillary shunt, the alveoli have the proper perfusion, but not the ventilation. Typically, the capillary shunt is commonly identified as the shunt. On the other hand, a capillary shunt occurs when the blood passes through the capillaries of alveoli without ventilation. Anatomical shunt occurs when the arterial blood returns to the pulmonary veins without passing through the pulmonary capillaries. They are the anatomical shunt and capillary shunt. Generally, pulmonary shunt can occur in two ways. Shunt or pulmonary shunt is one of the two contributors to the ventilation-perfusion (V/Q) mismatch. – Comparison of Key Differences Key TermsĪlveolar Dead Space, Alveoli, Capillary Shunt, Dead Space, Gas Exchange, Perfusion, Shunt What is the Difference Between Shunt and Dead Space What are the Similarities Between Shunt and Dead SpaceĤ. – Definition, Characteristics, Importanceģ. Moreover, they are examples of the ventilation-perfusion (V/Q) mismatch.

Shunt and dead space are two conditions of lungs, resulting in impaired gas exchange. Pulmonary embolism (PE) is an example of increased dead space resulted in decreasing perfusion relative to ventilation. For example, in pneumonia, the area of the alveoli is well perfused although it is not well ventilated, leading to the shunt. The main difference between the shunt and dead space is that shunt is the pathological condition in which the alveoli are perfused but not ventilated, whereas dead space is the physiological condition in which the alveoli are ventilated but not perfused.

Dead space lung