Tiêu đề item 6. Blood vessels, nerves and lymphatics of the thorax.pdf ✅

1 THORAX LECTURE NOTE : DON’T COPY Item 6. Blood vessels, nerves and lymphatics of the thorax The thorax is a vital region that houses the heart, lungs, major blood vessels, and other structures crucial for respiration and circulation. A thorough understanding of its vascular, nervous, and lymphatic anatomy is essential for medical students as it lays the foundation for clinical practice and pathology. 1. Blood Vessels of the Thorax A. Arteries : The major arteries in the thorax arise from the aorta & its branches: ● Ascending Aorta: Begins from the left ventricle and gives rise to coronary arteries. ● Arch of Aorta: Gives off three major branches: 1. Brachiocephalic trunk → right subclavian and right common carotid arteries. 2. Left common carotid artery 3. Left subclavian artery These arteries supply the head, neck, and upper limbs but also give off thoracic branches. ● Descending Thoracic Aorta: Gives off: ○ Posterior intercostal arteries (to the intercostal spaces) ○ Esophageal branches ○ Bronchial arteries (supply lungs and bronchi)

3 THORAX LECTURE NOTE : DON’T COPY 1. In the Neck ● Forms on the anterior surface of the scalenus anterior muscle. ● Lies deep to the prevertebral fascia and superficial to the anterior scalene. ● Runs posterior to the internal jugular vein and lateral to the carotid artery. ● It is crossed anteriorly by the transverse cervical and suprascapular arteries. 2. In the Thorax ● Enters the thorax by passing posterior to the subclavian vein and anterior to the lung root. ● Right Phrenic Nerve: Descends along the right side of the superior vena cava (SVC) and right atrium.Passes through the caval opening in the diaphragm (T8 level). ● Left Phrenic Nerve: Crosses the aortic arch and descends over the left ventricle. Pierces the diaphragm separately. Function of the Phrenic Nerve Motor Function : Sole motor supply to the diaphragm. Sensory Function Viva*** ● Supplies sensation to: ○ Central part of the diaphragm (parietal peritoneum) ○ Fibrous pericardium and parietal layer of serous pericardium ○ Medial side of cervical pleura ○ Mediastinal pleura ○ Central part of Diaphragmatic pleura Relations Region Anterior to Posterior to Neck Transverse cervical & suprascapular arteries Anterior scalene muscle Thorax Root of the lung Lung hilum and vagus nerve