General information
The lungs are used for breathing (ventilation) and ensure that oxygen is absorbed and carbon dioxide is released.
Anatomy of air conduction sections
Arterial supply
There are two types of vascular supply to the lungs (vascular supply to the lungs). Firstly, the oxygen-depleted blood from the heart reaches the lungs via the pulmonary arteries. These vessels are called public vessels (vasa publica) because they do not supply the lungs with oxygen, but the blood is enriched with oxygen only in the lungs.
The pulmonary arteries, together with the bronchi and the arterial branches of the bronchi, run directly in the individual lung segments (intrasegmental course) (vascular supply to the lungs). The oxygen-rich blood leaves the lungs again via the pulmonary veins (pulmonary vein) to the heart. The pulmonary veins run separately from the remaining vessels between the individual lung segments (intersegmental course).
The actual oxygen supply to the lungs is provided by bronchial branches (rami bronchiales). These branches emerge directly from the aorta and, because they only supply the lungs with oxygen, are called private vessels (Vasa Privata). It is important to know that the lungs cannot supply themselves with the inhaled oxygen, but are supplied with oxygen via the bronchial branches.
This is because the walls of the vessels are too thick in most areas of the lung and therefore the oxygen contained in the air we breathe cannot pass directly into the lung (diffuse). Only in the pulmonary alveoli does the oxygen diffuse into the smallest pulmonary capillaries, which then unite to form larger vessels and flow as pulmonary veins to the heart (pulmonary vascular supply).
