2- Thoracic Vessels (Small Animal).docx

- **Veins of the forelimb** - Superficial (cephalic) vein - The cephalic vein is very important for venipuncture and catheter placement. - The cephalic vein drains into the external jugular vein to the cranial vena cava and then to the r...

- **Veins of the forelimb** - Superficial (cephalic) vein - The cephalic vein is very important for venipuncture and catheter placement. - The cephalic vein drains into the external jugular vein to the cranial vena cava and then to the right atrium of the heart. - The accessory cephalic vein is not as frequently used for venipuncture or catheter placement. - Medial cubital vein - The medial cubital vein links the cephalic vein to the brachial vein (depe vein drainage). - Deep vein - Deep veins are satellite to arteries of the same name. - **Collateral Circulation** - Collateral circulation involves multiple arterial branches supplying one given area (or muscle). - If one artery is blocked, the collateral blood flow will prevent necrosis from happening in the servicing region. - **(Main) Arteries of the forelimb** - The main arteries of the forelimb include the subclavian artery, axillary artery, brachial artery, and median artery. - The **axillary artery** has 4 branches: external thoracic artery, lateral thoracic artery, subscapular artery, and cranial circumflex humeral artery. - **External thoracic artery** (1) - The external thoracic artery supplies the superficial pectoral muscle. - **Lateral thoracic artery** (2) - The lateral thoracic artery supplies the axillary lymph node, deep pectoral muscle, latissimus dorsi muscle, and cutaneous trunci muscle. - **Subscapular artery** (3) - The subscapular artery supplies the subscapularis muscles, part of the teres major muscle, and the scapula. - The [subscapular artery gives off 2 branches]: thoracodorsal and caudal circumflex humeral. - The **thoracodorsal** artery branch supplies the teres major muscle and latissimus dorsi muscle. - The **caudal circumflex humeral** artery branch courses laterally between the humerus and teres major muscle, supplying the shoulder joint. - **Cranial circumflex humeral artery** (4) - The cranial circumflex humeral artery supplies the biceps brachii muscle, and the shoulder joint. - The **brachial artery** has [6 branches]: deep brachial artery, bicipital artery, collateral ulnar artery, superficial brachial artery, transverse cubital artery, and common interosseous artery. - **Deep brachial artery** (1) - The deep brachial artery supplies the triceps muscle group. - The radial nerve is located near the deep brachial artery. - **Bicipital artery** (2) - The bicipital artery distally supplies the biceps brachii muscle. - **Collateral ulnar artery** (3) - The collateral ulnar artery is a large branch that runs deep to the medial head of the triceps muscle to the caudal elbow. - **Superficial brachial artery** (4) - The superficial brachial artery supplies the cranial surface and superficial brachium. - **Transverse cubital artery** (5) - The transverse cubital artery supplies the cranial elbow, diving deep into the elbow joint. - **Common interosseous artery** (6) - The common interosseous artery is short and dives between the radius and ulna. - The common interosseous artery has 3 branches which supply the antebrachium. - The **median artery** is the principal blood supply to the manus (front paw), and passes through the carpal canal. - The median artery primarily supplies the palmar aspect of the manus. - The [median artery has 2 branches]: Deep antebrachial artery, and Radial artery. - **Deep antebrachial artery** (1) - The deep antebrachial artery supplies the caudal (flexor) muscles of the antebrachium. - **Radial artery** (2) - The radial artery detaches from the median artery just proximal to the middle of the forearm, towards the radius, while supplying the manus.