Cat Dissection: Anterior and Veins

САТ DISSECТION: Ріп ANTERIOR ARTERIES AND VEINS NAME _ _ _ _ _ _ _ __ the structures below. ТеІІ what area of the body each artery or vein supplies/drains. 1. Anterior vena cava Drains blood from the upper body and delivers it to the right atrium of the heart 2. Brachiocephalic vein (also called innominate) З. Drains blood from the head, neck, and upper limbs, and carries it towards the superior vena cava External Jugular vein Drains blood from the scalp and face, and carries it towards the subclavian vein blood from the neck muscles and carries it towards the external jugular vein . 4. Transverse Jugular vein Drains 5. Anterior facial vein Drains blood from the anterior part of the face and carries it towards the internal jugular vein 6. Posterior facial vein 7. SubcJavian vein Drains blood from the posterior part of the face and carries it towards the internal jugular vein Drains blood from the upper extremities and carries it towards the brachiocephalic vein 8. Axillary vein Drains blood from the armpit region and carries it towards the subclavian vein 9. Brachial vein Drains blood from the arm and carries it towards the axillary vein Supplies blood to the head, neck, and right arm 10.Brachiocephalic artery 11.Left subclavian artery Supplies blood to the left arm and part of the chest wall 12.Right subclavian artery 13.Axillary artery (either) 14. Brachial arteries Supplies blood to the right arm and part of the chest wall Supplies blood to the armpit region and shoulder Supply blood to the upper arm 15.Carotid arteries (right and left) Supply blood to the head and neck Differences between the cat and human in this area: Size and Position: The relative size and position of these vessels may vary between cats and humans due to differences in anatomy and physiology. Anatomical Variations: Cats may have variations in the branching patterns of arteries and veins compared to humans. Physiological Differences: Cats may have adaptations in their circulatory system to suit their specific needs and locomotion patterns l POSTERIOR ARTERIES AND VEINS 1. Posterior vena cava (right and left) Drains blood from the lower body and delivers it to the right atrium of the heart 2. Adrenolumbar veins (right and left) Drain blood from the adrenal glands and lumbar region, and carry it towards the inferior vena cava З. Renal veins (right and left) Drain blood from the kidneys and carry it towards the inferior vena cava 4. lliolumbar veins (right and left) Drain blood from the iliac and lumbar regions and carry it towards the inferior vena cava 5. Spermatic or ovarian veins (may not see) б. Drain blood from the testes in males or ovaries in females and carry it towards the inferior vena cava or the left renal vein Common іІіас veins •Drain blood from the pelvis and lower limbs and carry it towards the inferior vena cava іІіас 7. External veins Drain blood from the lower limbs and carry it towards the common iliac veins Drain blood from the thigh and groin area and carry it towards the external iliac vein 8. Femoral veins 9. Deep femoral veins Drain blood from deep structures of the thigh and carry it towards the femoral vein 10. Greater Saphenous veins 11. lntercostals arteries 12. Thoracic aorta Supply blood to the intercostal muscles and surrounding tissues Supplies blood to the thoracic region, including the chest wall and organs 13. Abdominal aorta Supplies blood to the abdominal region, including the abdominal organs and muscles 14. Adrenolumbar arteries 15. Renal arteries 18. lnternal іІіас іІіас Supply blood to the adrenal glands and lumbar region Supply blood to the kidneys 16. lliolumbar arteries 17. External Drain blood from the leg and foot and carry it towards the femoral vein Supply blood to the iliac and lumbar regions arteries arteries 19. Femoral arteries Supply blood to the lower limbs Supply blood to the pelvic organs and structures Supply blood to the thigh and lower limb 20. Deep femoral arteries Supply blood to deep structures of the thigh 21. Greater Saphenous arteries Supply blood to the leg and foot VEINS - ANTERIOR REGION ARTERIES - ANTERIOR REGION We begin our study of the major blood vess_els with the veins which сапу blood to the heart from the head, forelimbs, shoulder, and thoracic region. The anterior veins Jie close to the surface of the body and are therefore studied before the arteries which lie deep to the veins. In doubly injected specimens veins will Ье blue, arteries will Ье red: This -is due to the latex dye with which they were injected. Тhis permits you to see these vessels more clearly and to differentiate between arteries and veiD.s. You have already exposed the heart and some of the major veins in your study of the thoracic cavity. Extend your incision into the neck агеа. If you have not yet done so, expose the trachea, larynx, and thyroid gl,and as in the photo. Remove the thymus gland carefull}' from the ventral surface of the heart and lower trachea. Your best dissection instrument at this point is the dissecting needle. Use it instead of а scalpel. or scissors to expose and follow the path of а blood vessel. Scalpels and scissors, especially in the hands of the novice tend to destroy rather than preserve or expose. It is used for clearing а blood vessel of the connective tissue adhering to it, to tear into а thin muscle layer to follow а vessel, to separate one blood vessel from another, or from the nerves associated with it. Proceed to expose the large veins suпounding the heart. Remove the major veins suпounding the heart. Тhis will enable you to expose the arteries. Use уош dissecting needle to clear arteries of connective tissue, to separtate them,and to follow them. Anterior Vena Cava - Locate the trunk of this major systemic vein above the heart. ·In the cat the term anterior vena cava is more сопесt and therefore preferred to superio:r vena cava. АІІ anterior veins lead into the anterior vena cava. Are there any exceptions? Where does the anterior vena cava • empty? Posterior Vena Cava - This is 'the major vein returning blood from the lower extremities and from the abdominal area. Again, this designatioII. in the cat is preferred to inferior vena cava. It can clearly Ье s~en rising from the diaphr"agm, which it has penetrated, to enter the heart at the right atrium together with the anterior vena cava. Innominate (Brachiocephali6) - Follow the anterior .vena cava cranially from the heart. It divides into two equal branches, the "V" shaped innominate veins also known as the brachiocephalic veins. Each of these is foпned Ьу the union of the subc1.avian vein frOm the shoulder and the external juguUlт vein from the neck. Jugular Veins - Two jugular veins lie along each side of the neck. Тhе larger exteтnal juguUlт drains the head and neck, while the intemal jugulaт vein drains the brain and spїnal cord. It empties into the extemal jugular vein. Subclavian - Тhis vein is а continuation of the .axillaтy vein in the-shoulder joint area. The axillary vein is а continuation of the bтachio,l vein in the arm. Intemal Mammary (Sternal) Vein - On the ventral surface of the anterior vena cava about one inch above the heart the inteтnal таттату or sternal· vein arises. It results from the Шlion Qf the pЗ:ired intemaJ mammary veins which drain theventral thoracic body wall and the mammary glands of female cats. "· Azygous - Push the right lung and the heart medially. On the dorsal body wall, to the right of the midline, and running parallel to it, observe а vein which enters the anterior vena cava near the heart. Only а very small portion of it is seen in the photo. Тhis unpaired vessel is the azygous vein. Carefully dissect its trarisverse tributaries, the inte'rcostal veins, one pairt,;;b~een each two ribs. It drains the dorsal body wall and the dorsal musculature. -'"' ~;,.::;· Jug..ilar Veins (continued) -Continue to trace the exteтnal fug;Uia.тvein cranially. At the level of the masseter, the cheek muscle, it divides to form the posterioт f(J,cial vein and the аntетіот facial vein. There is а third branching of the exteranJ juguiar slightly мitЄQor· to this, at the upper end of thё laiynx, forming the tтansveтse jugulaт vein. It crosses the neclc-vertfially-.to connect the right and left external jugularveins. Near the ear the posterior facial vein divides to fo_.1in the anterior auriculaтvein and the posteтior аитісиl,ат vein. Cephalic - This vein was seen on the lateral surface of the forelegwhen the cat was skinned. It is а long vein which continues up to the shoulder area and there joins the tтамvетsе sсари1.ат vein. This vein, in turn, enters the extemaI jugular vein (see photo). The cephalic and brachial vein are joined in the -inner, elbow -Ьу the median cubital vein. Pulmonary Artery - On the ve'nЬ-al surface of the heart passing dorsally and to the left is the large pulmonaтy aтtery. It originates in the rlght ventricle. Try tracing its two branches to the lungs. The pulmonary is the only artery injected with blue Iatex to indicate that it сапіеs deoxygenated blood. АІІ other arteries will appear red or pink because they have been-injected with red latex to indicate that the blood transported in them is oxygenated. Aorta - Locate the аотt11, the ]arges~ systemic artery of the body. It leaves the left venЬ-icle and passes to the left, dorsal to the pulmщ1ary artery. Near its origin the aorta gives off two brances, the right and left сото пату aтteries. Тhese pass over the surface of the ventricles sending branches deep into the myocardium, suppling the heart muscle with necessary nutrients and oxygen. • From its origin in the left ventric]e the aorta curves to the Ieft, passes dorsally and continues downward along the left side of the v~rtebral column. The proximal curved portion is called the аотtіс атсh. while the next segment of the aorta within the thorax is known as the thoтacic aorta. The aOitic arch gives rise to arteries that supply the neck, head, shoulders, and forelimbs. Wereas in man three arterial trunks arise from the aortic arch, in the cat there are only two. These are the: 1. BraclriocephaJic (or Innominate) - Тhis.is the first ari:erial branch of the aorta. As its name indicates it supplies blood to the forelimb and head. At the level of the second rib it divides into the: Right Subclavian - This artery leaves the thorax, gives off four major branches, then continues as the ахіЛа.rу artery in the armpit and shoulder region, then as the brachial arteтy in the upper forelimb. In the ]ower forelimb it branches to form-the тadial and the ulnaт arteтies. Right and Left Common Carotids - These two branches of the brachiocephalic artery rise craniaily and Не parallel to each other along either side of the trachea. 2. Left Subclavian - The second branch of the aortic arch is the left subclavian aтtery. It gives off branches similar to the right subclavian, then proceeds into the left forelimb as the left axillary, the left brachial, tbe left тadial, and the left ulnar arteries. Near the first rib the subclavian artery gives off four branches. These are the: Internal Mammary - This artery passes caudally to the ventral thoracic wаП and supplies the adjacent muscles, pericardium, and mammary glands with blOod. Vertebral - Тhis artery passes cranially through the vertebral canal of the cervical vertebrae giving off branches to deep neck muscles and to the spinal cord. It enters the foramen magnum of the skull to form the basilaт arteтy which suppJies the hind brain. Costocervical - This artery arises from the dorsal surface of the subclavian supplying the muscles of the neck and chest. At the upper border of the scapula it is called the tтansveтse scapular artery and it supplies the shoulder musc_Ies. The common carotid атtетіеs in their passage cranially give off the following arteries: Superior Thyroid - This artery supplies the thyroid gland, iaryngea] muscles, ventral neck muscles. Internal Carotid - Тhis artery enters the skull and joins the роstетіот ceтebral aтtery which supplies the brain. Extemal Carotid - Тhis artery is а continuation of the common carotid artery after it has given off the intemal carotid artery. Lingual - This ai-tery is·the major branch of the external carotid artery. It gives off branches ot the hyoid, pharyngeal muscles, then enters the tongue. ExtemaJ Ma,i;illary - This artery is а branch of the external carotid near the angle of the jaw. It passes along the ventraI border of the masseter muscle and· gives off bran-ches to the lips and mouth. Posterior Auricular and Superficial Тemporal - These two arteries are distal branches of the external carotid artery running dorsally and laterally to supply the muscles of the side and back of the head. The роstетіот аитісиlат атtету is located near the еаі", the superficial tempoтal атtе1у is found near the temple. VEINS • POSTERIO~ FП=G,іІЗ:!!11 Тhе aorta eontines caudally and passes through the diaphragm into the abdominal cavity. It is here knqwn as the ahdomiмl aorta. '·l.i_;,;,Z %?сС'::---, The systemic veins below the heart empty into the posterior vena cava. The upper portion of this enlarged blood vessel was observed when We studied the thoracic veins. It passes through the diaphragm and lies along the mid-dorsal body wall of the thorax. It enters the right atrium of the heart near the entrance Of the anterior vena cava. •