Difference between Blood supply of right and left lung

The blood supply of lungs involves both pulmonary circulation (for gas exchange) & bronchial circulation (for nutrition of lung tissues).

The right & left pulmonary arteries arise from pulmonary trunk & supply deoxygenated blood to the lungs.
Each pulmonary artery divides into lobar & segmental branches, following the bronchial tree.
After gas exchange in the alveoli, oxygenated blood returns via pulmonary veins to the left atrium.

Bronchial arteries supply oxygenated blood to lung tissues (bronchi, pleura, connective tissue).
- Right lung: Usually one bronchial artery, arising from the 3rd posterior intercostal artery or aorta.
- Left lung: Typically two bronchial arteries, arising from the descending thoracic aorta.
Bronchial veins drain some blood into:
- Azygos vein (right side)
- Hemiazygos vein (left side)
- Some blood drains into pulmonary veins (physiological shunt).

difference between anatomy

Feature	Right Lung	Left Lung
Main Pulmonary Artery	Right pulmonary artery (branches from the main pulmonary artery)	Left pulmonary artery (branches from the main pulmonary artery)
Bronchial Arteries	Usually one right bronchial artery, originating from the right posterior intercostal or directly from the descending thoracic aorta	Two left bronchial arteries, arising from the descending thoracic aorta (superior and inferior)
Pulmonary Veins	two from the right lung draining into the left atrium of heart	two from the left lun draining into the left atriumof heart
Venous Drainage	Right bronchial veins drain into the azygos vein	Left bronchial veins drain into the hemi-azygos vein
Lobes	Three lobes: upper, middle, lower	Two lobes: upper and lower
Lymphatic Drainage	Superficial and deep lymphatic plexuses draining into broncho-pulmonary lymph nodes	Similar lymphatic drainage as right lung, but specific nodes may differ