Bronchial circulation

Bronchial circulation refers to the part of the circulatory system that supplies nutrients and oxygen to the cells that constitute the lungs, as well as carrying waste products away from them. It is a component of the systemic circulation, as opposed to the pulmonary circulation.

Anatomy

The bronchial circulation originates from the aorta, a major systemic artery. The bronchial arteries, usually one for the left lung and two for the right lung, branch off from the aorta and follow the bronchial tree into the lungs. They supply the bronchi and connective tissue of the lungs, and also the lymph nodes in the mediastinum.

Physiology

The bronchial circulation serves several important functions. It provides oxygen and nutrients to the lung tissue itself, which is not served by the pulmonary circulation. It also warms and humidifies the air in the lungs, and aids in the immune defense of the lungs by transporting white blood cells and antibodies.

Clinical significance

Disruption of the bronchial circulation can lead to a variety of lung diseases. For example, bronchial artery embolism can occur if a blood clot blocks one of the bronchial arteries. This can cause hemoptysis (coughing up blood), shortness of breath, and chest pain.

Bronchial artery aneurysm is a rare but potentially life-threatening condition in which one of the bronchial arteries becomes enlarged. This can lead to massive hemoptysis if the aneurysm ruptures.

See also

• Pulmonary circulation
• Aorta
• Lung
• Bronchial artery embolism
• Bronchial artery aneurysm