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Veins of the systemic circulation

The veins of the systemic circulation are combined into three systems:

1. the vein system of the heart (see ""),
2. superior vena cava system and
3. the system of the inferior vena cava, into which the largest visceral vein of the human body, the portal vein, flows.

The portal vein with its tributaries is isolated as the portal vein system. Each system has a main trunk, into which veins flow, carrying blood from a certain group of organs. These trunks ( sinus coronarius cordis, v. cava superior, v. cava inferior) flow separately into the right atrium. There are anastomoses between the systems of the caval veins and the portal vein system.

Superior vena cava system

Rice. 142. Unpaired, semi-unpaired and additional semi-unpaired veins.
1-v. hemiazygos accessoria; 2-v. hemiazygos; 3-v. lumbalis ascendens sinistra: 4 - v. iliaca communis sinistra; 5-v. cava inferior (cut off); 6-v. lumbalis ascendens dextra; 7-v. azygos; 8 - vv. intercostales posteriores; 9-v. cava superior (cut off); 10-v. brachiocephalica dextra; 11-v. brachiocephalica sinistra.
See atlas, etc.

superior vena cava, v. cava superior(Fig. 142), is a short valveless thick vessel (diameter 21 - 25 mm, length 5-8 cm), which is formed as a result of the confluence of the right and left brachiocephalic veins behind the junction of the cartilage of the first right rib with the sternum. V. cava superior follows vertically down and at the level of connection of the III right cartilage with the sternum flows into the right atrium. In front of the vein are the thymus gland and the mediastinal part of the right lung covered by the pleura. The mediastinal pleura is adjacent to the vein to the right, and the ascending aorta is to the left. Behind v. cava superior is in contact with the anterior surface of the root of the right lung. The unpaired vein flows into the superior vena cava on the right, and the small mediastinal and pericardial veins on the left. V. cava superior collects blood from three groups of veins: veins of the head and neck, veins of both upper limbs and veins of the walls of the chest and partially abdominal cavities, i.e., from those areas that are supplied with blood by the branches of the arch and the thoracic part of the aorta.

Unpaired vein, v. azygos, is a continuation into the chest cavity of the right ascending lumbar vein ( v. lumbalis ascendens dextra), which lies behind the psoas major muscle and anastomoses on its way with the right lumbar veins, which flow into the inferior vena cava. Having passed between the muscle bundles of the right leg of the lumbar part of the diaphragm into the posterior mediastinum, v. lumbalis ascendens dextra is called the unpaired vein ( v. azygos). Behind and to the left of it are the spinal column, thoracic part aorta and thoracic duct, as well as the right posterior intercostal arteries. The esophagus lies in front of the vein. At the level of IV-V thoracic vertebrae v. azygos goes around the root of the right lung behind, goes forward and down and flows into the superior vena cava. There are two valves at the mouth of the unpaired vein. The veins of the posterior wall of the chest cavity flow into the unpaired vein on its way to the superior vena cava: the right superior intercostal vein, v. intercostalis superior dextra; posterior intercostal veins, IV-XI; semi-unpaired vein, through them - the veins of the external and internal vertebral plexuses ( plexus venosi vertebrales externi et interni), as well as veins of the organs of the chest cavity: esophageal veins, vv. esophageales; bronchial veins, vv. bronchiales; pericardial veins, vv. pericardiacae, and mediastinal veins, vv. mediastinales.

Semi-unpaired vein, v. hemiazygos(sometimes called the left, or small unpaired vein), thinner than the unpaired vein, since only 4-5 lower left posterior intercostal veins flow into it. The semi-unpaired vein is a continuation of the left ascending lumbar vein ( v. lumbalis ascendens sinistra), passes between the muscle bundles of the left leg of the diaphragm into the posterior mediastinum, adjacent to the left surface of the thoracic vertebrae. To the right of the semi-unpaired vein is the thoracic aorta, behind the left posterior intercostal arteries. At the level of the VII-X thoracic vertebrae, the semi-unpaired vein turns sharply to the right, crosses the spinal column in front (located behind the aorta, esophagus and thoracic duct) and flows into the unpaired vein ( v. azygos). The accessory semi-unpaired vein flows into the semi-unpaired vein from top to bottom, v. hemiazygos accessoria(see Fig. 142), which receives 6-7 upper intercostal veins ( vv. intercostales posteriori I-VII), as well as esophageal and mediastinal veins ( vv. esophageales mediastinalis). The most significant tributaries of the unpaired and semi-unpaired veins are the posterior intercostal veins, each of which is connected with its anterior end to the anterior intercostal vein ( v. intercostalis anterior) - inflow of the internal thoracic vein ( v. thoracica interna), which creates the possibility of outflow of venous blood from the walls of the chest cavity back into the unpaired and semi-unpaired veins and forward into the internal thoracic veins.

Rice. 143. Veins of the thoracic vertebra; top view (cross section).
1 - plexus venosus vertebralis externus posterior; 2 - processus transversus; 3-r. dorsalis v. intercostalis posterioris; 4 - plexus venosus vertebralis internus posterior; 5 - plexus venosus vertebralis internus anterior; 6 - plexus venosus vertebralis externus anterior; 7 - corpus vertebrae; 8 - canalis vertebralis; 9 - processus spinosus.
See atlas, etc.

posterior intercostal veins, vv. intercostales posteriores, are located in the intercostal spaces next to the arteries of the same name, in the groove under the corresponding rib, and collect blood from the tissues of the walls of the chest cavity and partly the anterior abdominal wall(lower posterior intercostal veins). Into each of the posterior intercostal veins flow: a branch of the back, r. dorsalis, which is formed in the skin and in the muscles of the back; intervertebral vein, v. intervertebralis, formed from the veins of the external and internal vertebral venous plexuses; a spinal branch flows into each intervertebral vein r. spinalis, which, along with other veins (vertebral, lumbar and sacral) is involved in the outflow of venous blood from the spinal cord.

Rice. 144. Veins of the spine. Sagittal section of a fragment of the spine. View from the cutting side.
1 - plexus venosus vertebralis externus anterior; 2 - plexus venosus vertebralis internus anterior; 3 - plexus venosus vertebralis internus posterior; 4 - plexus venosus vertebralis externus posterior; 5 - processus spinosus; 6 - corpus vertebrae.

Internal vertebral venous plexuses (anterior and posterior), plexus venosi vertebrales interni (anterior et posterior)(Fig. 143, 144), are located inside the spinal canal (between the hard shell of the spinal cord and the periosteum) and are represented by veins that repeatedly anastomose with each other. The plexuses extend from the foramen magnum above to the top of the sacrum below. The spinal veins drain into the internal vertebral plexuses ( vv. spinales) and veins of the spongy substance of the vertebrae. From these plexuses, blood flows through the intervertebral veins passing through the intervertebral foramina (next to the spinal nerves), flows into the unpaired, semi-azygous and additional semi-azygous veins into the external venous vertebral plexuses (anterior and posterior) ( plexus venosi vertebrales externi (anterior et posterior), which are located on the anterior surface of the vertebrae, and also braid their arcs and processes. The outflow of blood from the external vertebral plexuses occurs in the posterior intercostal, lumbar and sacral veins ( vv. intercostales posteriores, lumbales and sacrales), as well as directly into the unpaired, semi-unpaired and additional semi-unpaired veins. At the level of the upper part of the spinal column, the veins of the plexuses flow into the vertebral and occipital veins ( vv. vertebrales, vv. occipitales).

Brachiocephalic veins (right and left), vv. brachiocephalicae (dextra et sinistra)(Fig. 145), valveless, are the roots of the superior vena cava, collect blood from the organs of the head and neck and upper limbs. Each brachiocephalic vein is formed from two veins - the subclavian and the internal jugular.

The left brachiocephalic vein is formed behind the left sternoclavicular joint, has a length of 5-6 cm, follows from the place of its formation obliquely down and to the right behind the handle of the sternum and thymus. Behind the vein are the brachiocephalic trunk, the left common carotid and subclavian arteries. At the level of the cartilage of the right I rib, the left brachiocephalic vein connects with the right vein of the same name, forming the superior vena cava.

The right brachiocephalic vein forms behind the right sternoclavicular joint (the length of the vein is 3 cm), descends almost vertically behind the right edge of the sternum and is adjacent to the dome of the right pleura. Small veins drain into each of these veins. internal organs: thymus veins, vv. thymicae; pericardial veins, vv. pericardiacae; pericardial phrenic veins, vv. pericardiacophrenicae; bronchial veins, vv. bronchiales; esophageal veins, vv. esophageales; mediastinal veins, vv. mediastinales(from lymph nodes and connective tissue mediastinum).

Larger tributaries of the right and left brachiocephalic veins are 1-3 inferior thyroid veins, vv. thyroideae inferiores, through which blood flows from the unpaired thyroid plexus ( plexus thyroidus impar), inferior laryngeal vein, v. laryngea inferior, bringing blood from the larynx, which anastomoses with the superior and middle thyroid veins.

Vertebral vein and deep cervical vein v. vertebralis et v. cervicalis profunda. The first of them accompanies the vertebral artery, passes with it through the transverse openings of the cervical vertebrae to the brachiocephalic vein ( v. brachiocephalica), taking on its way the veins of the internal vertebral plexuses. The deep jugular vein originates from the external vertebral plexuses and also collects blood from the muscles located in the occipital region. This vein passes behind the transverse processes of the cervical vertebrae and flows into the brachiocephalic vein near the mouth of the vertebral vein or directly into the vertebral vein.

internal thoracic veins, vv. thoracicae internae. They accompany the internal thoracic artery, two on each side. Their roots are the superior epigastric and musculophrenic veins, vv. epigastricae superiores et vv. musculophrenicae. The first of them anastomose in the thickness of the anterior abdominal wall with the lower epigastric veins flowing into the external iliac vein. The anterior intercostal veins, lying in the anterior intercostal spaces, flow into the internal thoracic veins, vv. intercostals anteriores that anastomose with the posterior intercostal veins ( vv. intercostales posteriores), flowing into the unpaired and semi-unpaired veins.

The highest intercostal vein flows into the brachiocephalic vein of each side, v. intercostalis suprema, collecting blood from 3-4 upper intercostal spaces.

Veins of the head and neck

Rice. 145. Internal jugular and subclavian veins and their tributaries.
1-v. annularis 2-v. facialis; 3-v. submentalis; 4-v. thyroidea superior; 5-v. laryngea superior; 6-v. jugularis interna; 7-v. jugularis externa (cut off); 8-v. brachiocephalica dextra; 9-vv. brachiales; 10-v. brachialis medialis; 11-v. axillaris; 12-v. cephalica; 13-v. subclavia; 14-v. retromandibularis.
See atlas, etc.

Internal jugular vein , v. jugularis interna(see Fig. 145), - a large vessel, which, together with the external jugular vein ( v. jugularis externa) collects blood from the head and neck, from areas corresponding to the branching of the external and internal carotid and vertebral arteries.

V. jugularis interna is a direct continuation of the sigmoid sinus meninges. It begins at the level of the jugular foramen, below which there is a small expansion - the superior bulb of the internal jugular vein ( bulbus venae jugularis superior). Initially, the vein is located behind the internal carotid artery, and then laterally and lies behind the common carotid artery in common with it and the vagus nerve fascial sheath. Before confluence with the subclavian vein ( v. subclavia) there is a second extension - the lower bulb of the internal jugular vein, bulbus venae jugularis inferior, above and below which there is one paired valve in the vein.

Through the sigmoid sinus, from which the internal jugular vein originates, venous blood flows from the system of sinuses of the hard shell of the brain. Superficial and deep cerebral veins flow into these sinuses, collecting blood from the brain - diploic, as well as ophthalmic veins and labyrinth veins, which can be considered as intracranial tributaries of the internal jugular vein.

diploic veins, vv. diploicae, valveless, through them the blood flows from the bones of the skull. These thin-walled, relatively wide veins originate in the spongy substance of the bones of the cranial vault (formerly they were called cancellous veins). In the cranial cavity, they communicate with the meningeal veins and sinuses of the hard shell of the brain, and outside, through the emissary veins, with the veins of the outer integument of the head. The largest of these veins are the frontal diploic vein, v. diploica frontalis, flows into the superior sagittal sinus; anterior temporal diploic vein v. diploica temporalis anterior, flows into the sphenoparietal sinus; posterior temporal diploic vein, v. diploica temporalis posterior, flows into the mastoid emissary vein, and the occipital diploic vein, v. diploica occipitalis, flows into the transverse sinus or into the occipital emissary vein.

superior and inferior ophthalmic veins, vv. ophthalmicae superior and inferior, valveless. The veins of the nose and forehead flow into the first of them, the larger one, upper eyelid, ethmoid bone, lacrimal gland, membranes eyeball and most of his muscles. V. ophthalmica superior in the region of the medial angle of the eye, it anastomoses with the facial vein ( v. facialis). V. ophthalmica inferior is formed from the veins of the lower eyelid, neighboring muscles of the eye, lies on the lower wall of the orbit under optic nerve and flows into the superior ophthalmic vein, which exits the orbit through the superior orbital fissure and flows into the cavernous sinus.

Veins of the labyrinth vv. labyrinthi, exit it through the internal auditory meatus and flow into the inferior petrosal sinus.

Sinuses of the dura mater with the help of emissary veins ( vv. emissariae) connect with veins located in the outer integument of the head. Emissary veins are located in small bone canals, through which blood flows outward from the sinuses, i.e., to the veins that collect blood from the outer integument of the head. The parietal emissary vein is exposed, v. emissaria parietalis, which passes through the parietal opening of the bone of the same name and connects the superior sagittal sinus with the external veins of the head; mastoid emissary vein, v. emissaria mastoidea located in the mastoid canal temporal bone; condylar emissary vein, v. emissaria condylaris, penetrates through the condylar canal of the occipital bone. The parietal and mastoid emissary veins connect the sigmoid sinus with tributaries of the occipital vein, and the condylar also with the veins of the external vertebral plexus.

Extracranial tributaries of the internal jugular vein are the following veins:

1. pharyngeal veins, vv. pharyngeae, valveless, carry blood from the pharyngeal plexus ( plexus pharyngeus), which is located on the posterior and lateral surfaces of the pharynx. Venous blood flows into it not only from the pharynx, but also from auditory tube, soft palate and back of the hard shell of the brain;
2. lingual vein, v. lingualis, which is formed by the dorsal and deep veins of the tongue, vv. dorsales linguae et v. profunda linguae, and the hyoid vein, v. sublingualis;
3. superior thyroid vein, v. thyroidea superior(sometimes flows into the facial vein), accompanies the artery of the same name, has valves. The superior laryngeal vein drains into the superior thyroid vein v. laryngea superior, and sternocleidomastoid vein, v. sternocleidomastoidea. In some cases, one of the thyroid veins runs laterally to the internal jugular vein and flows into it independently as the middle thyroid vein, v. thyroidea media;
4. facial vein, v. facialis, flows into the internal jugular vein at the level of the hyoid bone. Smaller veins flow into it, forming in soft tissues face (angular vein, v. angularis; supraorbital vein, v. supraorbitalis; veins of the upper and lower eyelids, vv. palpebrales superiores and inferiores; external nasal veins vv. nasales externae; superior and inferior labial veins, vv. labiales superior and inferior; palatine vein, v. palatina; submental vein, v. submentalis; branches parotid gland, rr. parotidei; deep vein of the face v. faciei profunda);
5. mandibular vein, v. retromandibularis, is a fairly large vessel. It goes in front of the auricle, passes through the parotid gland behind the branch mandible(outside of the external carotid artery), flows into the internal jugular vein. Collects blood from the auricle ( vv. auriculares anteriores), temporal and parietal regions of the head ( vv. temporales superficiales, mediae, profundae), temporomandibular joint ( vv. articularis temporomanibularis), pterygoid (venous) plexus [ plexus (venosus) pterygoideus], into which the middle meningeal veins flow ( vv. meningeae mediae), from the parotid gland ( vv. parotideae), middle ear ( vv. tympaniçae).

External jugular vein, v. jugularis externa(see Fig. 145), is formed at the anterior edge of the sternocleidomastoid muscle by the confluence of its two tributaries - the anterior one, which is an anastomosis with the submandibular vein ( v. retromandibularis), which flows into the internal jugular vein, and the posterior, formed by the confluence of the occipital and posterior ear veins ( v. occipitalis et v. auricularis posterior). The external jugular vein goes down the anterior surface of the sternocleidomastoid muscle to the clavicle, pierces the pretracheal plate of the cervical fascia and flows into the confluence of the subclavian and internal jugular veins or a common trunk with the latter - into the subclavian. At the level of its mouth and in the middle of the neck, this vein has two paired valves. The suprascapular vein flows into it, v. suprascapularis, anterior jugular vein and transverse veins of the neck, vv. transversae colli.

anterior jugular vein, v. jugularis anterior(see Fig. 145), is formed from the small veins of the mental region, follows down in the anterior region of the neck, pierces the pretracheal plate of the cervical fascia, penetrates into the interfascial suprasternal space. In this space, the left and right anterior jugular veins are connected by a transverse anastomosis, forming the jugular venous arch ( arcus venosus juguli). This arc, on the right and on the left, flows into the external jugular vein of the corresponding side.

subclavian vein, v. subclavia, - an unpaired trunk, is a continuation of the axillary vein, passes in front of the anterior scalene muscle from the lateral edge of the 1st rib to the sternoclavicular joint, behind which it connects to the internal jugular vein. At the beginning and at the end, the subclavian vein has a valve; it does not receive constant tributaries. More often than others, small thoracic veins flow into the subclavian vein, vv. pectorales, and dorsal scapular vein, v. scapularis dorsalis.

Veins of the upper limb

Rice. 146. Superficial (subcutaneous) veins.
1-vv. temporales superficiales; 2-v. jugularis externa; 3-v. jugularis anterior; 4-v. cephalica; 5 - arcus venosus palmaris superficialis; 6v. intermedia cubiti (v. mediana cubiti - BNA); 7-v. basilica; 8-v. epigastric superficialis; 9-v. saphena magna; 10 - rete venosus dorsalis pedis; 11-v. facialis.

Allocate superficial and deep veins of the upper limb. They are interconnected by a large number of anastomoses and have numerous valves. Superficial (subcutaneous) (Fig. 146) veins are more developed than deep ones (especially on the back of the hand). From them begin the main venous pathways - the lateral and medial saphenous veins of the hand, which receive blood from the venous plexus of the back surface of the fingers.

dorsal metacarpal veins, vv. metacarpeae dorsales(four), and the anastomoses between them form the dorsal venous network of the hand on the back surface of the fingers, metacarpus and wrist ( rete venosum dorsale manus). On the palmar surface of the hand superficial veins thinner than the back. They begin with a plexus on the fingers, in which the palmar finger veins are isolated, vv. digitales palmares. Through numerous anastomoses, located mainly on the lateral edges of the fingers, blood flows into the dorsal venous network of the hand.

The superficial veins of the forearm, into which the veins of the hand continue, form a plexus; the lateral and medial saphenous veins of the arm are clearly distinguished in it.

Lateral saphenous vein of the arm v. cephalica(see Fig. 147), starts from the radial part of the venous network of the dorsum of the hand, being, as it were, a continuation of the first dorsal metacarpal vein ( v. metacarpea dorsalis I). It follows from the back surface of the hand to the anterior surface of the radial edge of the forearm, receives numerous skin veins of the forearm along the way and, becoming larger, goes to the cubital fossa. Here it anastomoses through the intermediate vein of the elbow with the medial saphenous vein of the arm and continues to the shoulder, where it lies in the lateral groove of the biceps brachii muscle, and then in the groove between the deltoid and pectoralis major muscles, pierces the fascia and flows under the clavicle into the axillary vein.

Rice. 147. Superficial (subcutaneous) veins of the right upper limb.
1-v. cephalica; 2-v. basilica; 3-v. intermedi; basilica; 4-v. intermedia cephalica; 5-v. intermedia cubiti (v. mediana cubiti - BNA).
See atlas, etc.

Medial saphenous vein of the arm v. basilica(see Fig. 146, 147), is a continuation of the fourth dorsal metacarpal vein ( v. metacarpea dorsalis IV), passes from the back of the hand to the ulnar side of the anterior surface of the forearm and follows towards the cubital fossa, where it receives the intermediate vein of the elbow. Further, the medial saphenous vein rises along the medial groove of the biceps muscle of the shoulder to the shoulder, at the border of its lower and middle thirds it pierces the fascia and flows into one of the brachial veins.

Intermediate vein of elbow v. intermedia cubiti, which does not have valves, is located under the skin in the anterior elbow region. Passes obliquely from the lateral saphenous vein of the arm ( v. cephalica) to the medial saphenous vein of the arm ( v. basilica), anastomosing also with deep veins. Often, in addition to the lateral and medial saphenous veins, the intermediate vein of the forearm is located on the forearm, v. intermedia antebrachii. In the anterior ulnar region, it flows into the intermediate vein of the elbow or divides into two branches, which independently flow into the lateral and medial saphenous veins of the arm.

Deep (paired) veins of the palmar surface of the hand accompany arteries, form superficial and deep venous arches.

The palmar digital veins drain into the superficial palmar venous arch ( arcus venosus palmaris superficialis), located near the arterial superficial palmar arch. Paired palmar metacarpal veins vv. metacarpeae palmares, are sent to the deep palmar venous arch ( arcus venosus palmaris profundus). The deep palmar venous arch, as well as the superficial one, continue into the deep veins of the forearm - the paired ulnar and radial veins ( vv. ulnaris et vv. radiales), which accompany the arteries of the same name.

Two brachial veins formed from the deep veins of the forearm, vv. brachiales, not reaching the axillary vein, merge into one trunk, which, at the level of the lower edge of the tendon of the latissimus dorsi muscle, passes into the axillary vein ( v. axillaris). This vein continues to the lateral edge of the 1st rib, where it passes into the subclavian vein ( v. subclavia). V. axillaris, like its tributaries, has valves; it is adjacent to the anteromedial semicircle of the axillary artery, collects blood from the superficial and deep veins of the upper limb. Its tributaries correspond to the branches of the axillary artery. The most significant tributaries of the axillary vein are the lateral thoracic vein, v. thoracica lateralis into which the thoracic veins empty vv. thoracoepigastricae, anastomosing with the inferior epigastric vein ( v. epigastric inferior) - inflow of the external iliac vein. V. thoracica lateralis also receives thin veins that branch off from I-VII posterior intercostal veins ( vv. intercostales posteriores I-VII). Venous vessels flow into the thoracic veins, which exit from the peripapillary venous plexus ( plexus venosus areolaris), formed by the saphenous veins of the mammary gland.

Inferior vena cava system

Rice. 148. Superior and inferior vena cava and their tributaries.
1-v. brachiocephalica sinistra; 2 - arcus aortae; 3 - truncus pulmonalis; 4-v. phrenica inferior; 5-v. lienalis (cut off); 6-v. suprarenalis sinistra; 7-v. renalis sinistra; 8-v. iliaca communis sinistra; 9-v. iliaca interna sinistra; 10-v. iliaca externa sinistra; 11-v. saphena magna; 12-vv. pudendae externae; 13-v. femoralis; 14-v. iliaca communis dextra; 15-v. cava inferior; 16-v. testicularis dextra, 17 - v. testicular sinistra; 18 - pars abdominalis aortae; 19-vv. hepaticae; 20-v. cava superior; 21-v. brachiocephalica dextra; 22-v. subclavia dextra; 23-v. jugularis interna dextra.
See atlas, etc.

inferior vena cava, v. cava inferior(Fig. 148), the largest, has no valves, is located retroperitoneally, begins at the level intervertebral disc between the IV and V lumbar vertebrae from the confluence of the left and right common iliac veins on the right and slightly below the division of the aorta into the same arteries. At the beginning v. cava inferior follows up the anterior surface of the right psoas major muscle. Located to the right of the abdominal part of the aorta, the inferior vena cava passes behind the horizontal part duodenum, behind the head of the pancreas and the root of the mesentery, lies in the sulcus of the same name of the liver, taking the hepatic veins. Upon exiting the groove, it passes through its own opening of the tendon center of the diaphragm into the posterior mediastinum of the chest cavity, penetrates into the pericardial cavity and, being covered by the epicardium, flows into the right atrium. IN abdominal cavity behind the inferior vena cava are the right sympathetic trunk, the initial sections of the right lumbar arteries and the right renal artery.

Inflows of the inferior vena cava: distinguish between parietal and visceral tributaries of the inferior vena cava.

Parietal tributaries:

1) three or four lumbar veins, vv. lumbales; their course and the areas from which they collect blood correspond to the branches of the lumbar arteries. Often vv. lumbales I and II drain into an unpaired vein v. azygos), and not in the lower hollow. The lumbar veins of each side anastomose with each other using the ascending lumbar vein ( v. lumbalis ascendens) (see Fig. 136). In the lumbar veins through the spinal branches (rr. spinales) blood flows from the vertebral venous plexuses;

2) inferior phrenic veins, vv. phrenicae inferiores, right and left, adjoin two to the artery of the same name, flow into the inferior vena cava after it exits from the sulcus of the same name in the liver.

Visceral tributaries of the inferior vena cava:

1) testicular (ovarian) vein; v. testicularis (ovarica), steam room, starts from the posterior edge of the testicle (from the gate of the ovary) with numerous veins that braid the artery of the same name, forming a pampiniform (vine-shaped) plexus, plexus pampiniformis, which in men is part of the spermatic cord. Merging with each other, small veins form one venous trunk on each side. V. testicularis (ovarica) dextra flows at an acute angle into the inferior vena cava, a v. testicularis (ovarica) sinistra- at a right angle to the left renal vein;

2) renal vein, v. renalis, steam room, goes from the gate of the kidney in a horizontal direction (in front of the renal artery) and flows at the level of the intervertebral disc between the I and II lumbar vertebrae into the inferior vena cava. The left renal vein is longer than the right one and runs anterior to the aorta. Both veins anastomose with the lumbar, as well as the right and left ascending lumbar veins (vv. lumbales, vv. lumbales ascendens dextra et sinistra);

3) adrenal vein v. suprarenalis, - a short valveless vessel, exits the gate of the adrenal gland. The left adrenal vein drains into the left renal vein, and the right into the inferior vena cava. The superficial adrenal veins flow partly into the tributaries of the inferior vena cava (into the inferior phrenic, lumbar, renal veins), partly into the tributaries of the portal vein (into the pancreatic, splenic, gastric veins);

4) hepatic veins, vv. hepaticae, there are 3-4 of them, located in the liver parenchyma (the valves in them are not always expressed). They fall into the inferior vena cava in the place where it lies in the groove of the liver. One of the hepatic veins (usually the right one) before flowing into the inferior vena cava is connected to the venous (arancia) ligament of the liver ( lig. venosum) - overgrown venous duct, functioning in the fetus.

portal vein system

Rice. 149. Portal vein and its tributaries. 1-v. portac; 2-v. gastroepiploica sinistra; 3-v. gastric sinistra; 4 - lien; 5-v. lienalis; 6 - cauda pancreatis; 7-v. mesenterica superior; 8-v. mesenterica inferior; 9 - colon descendens; 10 - rectum; 11-v. rectalis inferior; 12-v. rectalis media; 13-v. rectalis superior; 14 - ileum; 15 - colon ascendens; 16 - caput pancreatis; 17-v. gastroepiploica dextra; 18-v. cystica; 19 - vesica fellea; 20 - duodenum (cut off and turned away); 21 - hepar; 22-v. prepylorica; 23 - ventriculus (turned away).
See atlas, etc.

A special place among the veins that collect blood from the internal organs is portal vein, v. portae(Fig. 149). This is not only the largest visceral vein of the human body (length 5-6 cm, diameter 11-18 mm), but it is also the bringing venous link of a special, so-called portal, liver system. V. portae located in the thickness of the hepatoduodenal ligament behind the hepatic artery and common bile duct along with nerves, lymph nodes and vessels. It is formed from the veins of unpaired organs of the abdominal cavity (stomach, small and large intestine, except for the anal canal of the rectum, spleen, pancreas). Venous blood from these organs through the portal vein follows through the liver, and from it through the hepatic veins into the inferior vena cava. The main tributaries of the portal vein are the superior mesenteric and splenic veins, as well as the inferior mesenteric vein, which merge with each other behind the head of the pancreas. Entering the gate of the liver, v. portae splits into a larger right ( r. dexter) and left ( r. sinister) branches. Each of them, in turn, breaks up into segmental, and then into branches of ever smaller diameter, which pass into the interlobular veins. Inside the lobules, they break up into wide capillaries, the so-called sinusoids, which flow into the central vein (Fig. 150). The sublobular veins emerging from each lobule, merging, form 3-4 hepatic veins, vv. hepaticae. So, the blood flowing into the inferior vena cava through the hepatic veins passes on its way through two capillary networks. One of them is in the wall. digestive tract, where the tributaries of the portal vein originate, the second - in the parenchyma of the liver, represented by the capillaries of its lobules (the so-called miraculous venous network, rete mirabile venosum).

Before entering the portal of the liver (in the thickness of the hepatoduodenal ligament), the gallbladder vein flows into the portal vein, v. cystica(from the gallbladder), as well as the right and left gastric veins, vv. gastricae dextra et sinistra and prepyloric vein v. prepylorica that carry blood from the corresponding parts of the stomach. The left gastric vein anastomoses with the esophageal veins ( vv. esophageales) - tributaries of the unpaired vein from the system of the superior vena cava. In the thickness of the round ligament of the liver, the paraumbilical veins follow to the liver, vv. paraumbilicales, starting in the navel, where they anastomose with the superior epigastric veins ( vv. epigastricae superiores) - tributaries of the internal thoracic veins ( vv. thoracicae internae- from the system of the superior vena cava) and with the superficial and inferior epigastric veins ( vv. epigastricae superficiales et inferior) - tributaries of the femoral and external iliac veins from the system of the inferior vena cava (Fig. 151).

A- formation of the portal vein; own hepatic artery and common bile duct: 1 - v. pancreatica; 2 - duodenum; 3 - vv. jejunales et ileales; 4-v. mesenterica superior; 5 - ductus choledochus; 6-v. portae; 7-v. mesenterica inferior; 8-v. lienalis; 9 - lien; 10 - colon transverse; 11 - pancreas;
b- branching of the portal vein and hepatic artery in the liver; formation of the common bile duct: 1 - hepar; 2 - vesica fellea; 3-v. portae; 4 - ductus cysticus; 5 - ductus hepaticus communis; 6-r. dexter v. portae; 7 - arteriola, venula et ductus interlobulares; 8-v. centralis; 9-v. hepatica; 10-v. sublobularis; 11-r. sinister v. portae; 12-rr. segmentales; 13 - ductus choledochus; 14-v. cava inferior; 15 - pars abdominalis aortae; 16-a. hepatica propria;
V- microvessels and bile ducts liver lobules: 1 - venula interlobularis; 2 - ductus interlobularis; 3 - arteriola interlobularis; 4 - vasa sinusoidea; 5-v. centralis; 6 - venula septalis; 7 - arteriola septalis; 8-ductulus interlobularis; 9-ductus biliferus.

Portal tributaries:

1) superior mesenteric vein, v. mesenterica superior(see Fig. 149), goes to the root of the mesentery small intestine to the right of the artery of the same name. Its tributaries are the veins of the jejunum and ileum, vv. jejunales and ileales; pancreatic veins, vv. pancreaticae; pancreatoduodenal veins, vv. pancreaticoduodenales; iliac vein, v. ileocolica; right gastroepiploic vein, v. gastroepiploica dextra; right and middle colic veins and vein appendix, vv. colicae media and dextra, v. appendicularis. The superior mesenteric vein, through the listed veins, collects blood from the walls of the jejunum and ileum and their mesentery, from the caecum and appendix, ascending and transverse colon, partly from the stomach, duodenum and pancreas, greater omentum;

2) splenic vein, v. lienalis (splenica), is located along the upper edge of the pancreas below the splenic artery, runs from left to right, crossing the aorta in front, and merges with the superior mesenteric vein behind the head of the pancreas. Its tributaries are the pancreatic veins, vv. pancreaticae, short gastric veins, vv. gastricae breves, and the left gastroepiploic vein, v. gastroepiploica sinistra. The latter anastomoses along the greater curvature of the stomach with the right vein of the same name. The splenic vein collects blood from the spleen, part of the stomach, pancreas, and greater omentum;

3) inferior mesenteric vein, v. mesenterica inferior, is formed by the confluence of the superior rectal vein ( v. rectalis superior), left colic vein ( v. colic sinistra) and sigmoid veins ( vv. sigmoideae). Located next to the left colic artery, the inferior mesenteric vein goes up, passes under the pancreas and flows into the splenic vein (sometimes into the superior mesenteric vein). V. mesenterica inferior collects blood from the walls of the upper rectum, sigmoid and descending colon.

Veins of the pelvis and lower limb

Common iliac vein, v. iliaca communis(see Fig. 151), - a large unpaired valveless vessel, formed at the level of the sacroiliac joint at the confluence of the internal and external iliac veins. The right common iliac vein is located behind, and then lateral to the artery of the same name, the left one is more medial (the median sacral vein flows into it, v. sacralis mediana).

Rice. 151. Scheme of anastomoses between the portal, superior and inferior vena cava.
1-v. cava superior; 2-v. brachiocephalica sinistra; 3-v. hemiazygos accessoria; 4 - vv. intercostales posteriores sinistrae; 5-v. azygos; 6 - plexus venosus esophageus; 7-v. hemiazygos; 8 - vv. intercostales posteriores dextrae; 9 - anastomosis between the portal and superior vena cava; 10-v. gastric sinistra; 11-v. portae; 12-v. lienalis; 13-v. mesenterica interior; 14-v. renalis sinistra; 15-v. cava inferior: 16 - vv. testiculares (ovaricae); 17-v. rectalis superior; 18-v. iliaca communis sinistra; 19-v. iliaca interna sinistra; 20-vv. rectales mediae; 21 - plexus venosus rectalis (connects the system of the inferior vena cava with the portal); 22-v. epigastric superficialis; 23-v. epigastric inferior; 24-v. mesenterica superior; 25 - anastomosis between the upper and lower hollow and portal veins; 26-vv. paraumbilicales; 27 - hepar; 28-v. epigastric superior; 29-v. thoracoepigastrica; 30-v. thoracica interna; 31-v. subclavia dextra; 32-v. jugularis interna dextra; 33-v. brachiocephalica dextra.

Both common iliac veins at the level of the intervertebral disc between the IV and V lumbar vertebrae merge into the inferior vena cava.

Internal iliac vein, v.iliaca interna(see Fig. 151), rarely has valves, lies on the side wall of the small pelvis behind the artery of the same name. The areas from which blood is taken out by its tributaries correspond (with the exception of the umbilical vein) to the branches of the artery of the same name. V. iliaca interna has parietal and visceral tributaries.

Parietal tributaries of the internal iliac vein: superior and inferior gluteal veins, vv. gluteae superiores and inferiores, obturator veins, vv. obturatoriae, lateral sacral veins, vv. sacrales laterales(paired), as well as the iliac-lumbar vein, v. iliolumbalis(unpaired). These veins are adjacent to the arteries of the same name and have valves.

The visceral tributaries of the internal iliac vein, with the exception of the veins of the bladder, do not have valves. As a rule, they start from the following venous plexuses surrounding the pelvic organs:

1. sacral plexus ( plexus venosus sacralis), which is formed due to anastomoses of the sacral lateral and median veins ( vv. sacrales laterales et v. sacralis mediana);
2. prostatic venous plexus ( plexus venosus prostaticus) in men - a dense plexus of large veins surrounding the prostate gland and seminal vesicles, into which the deep dorsal vein of the penis flows, v. dorsalis penis profunda, deep veins of the penis, v. profundae penis, and posterior scrotal veins, vv. scrotales posteriores entering the pelvic cavity through urogenital diaphragm; in women, there is a venous plexus surrounding the urethra, which passes posteriorly into the vaginal venous plexus ( plexus venosus vaginalis). Above, this plexus passes into the uterine venous plexus ( plexus venosus uterinus) surrounding the cervix. The outflow of blood from these plexuses occurs through the uterine veins, vv. uterinae;
3. vesical venous plexus ( plexus venosus vesicalis) covering bladder from the sides and in the area of ​​its bottom. Blood from this plexus flows through the vesical veins ( vv. vesicales);
4. rectal venous plexus ( plexus venosus rectalis), which is adjacent to the rectum from behind and from the sides, and is also located in its submucosa. It is most difficult to develop in the lower rectum. From this plexus, blood flows through one unpaired upper and two paired middle and lower rectal veins. superior rectal vein, v. rectalis superior flows into the inferior mesenteric vein. Middle rectal veins vv. rectales mediae, paired, carry blood from the middle section of the organ (flow into the internal iliac vein). inferior rectal veins, vv. rectales inferiores, paired, blood flows through them into the internal pudendal vein ( v. pudenda interna- inflow of the internal iliac vein).

The veins of the human body are interconnected by numerous anastomoses. Greatest practical value have intersystem venous anastomoses, i.e., those with the help of which the systems of the superior and inferior caval and portal veins are interconnected (Table 5).

Veins of the lower extremities

Rice. 152. Great saphenous vein of the right lower limb and its tributaries in the leg and foot.
1-v. saphena magna; 2 - rete venosum calcaneum (BNA); 3 - a branch connecting the subcutaneous (superficial) veins with deep ones; 4 - vv. digitales dorsales pedis; 5 - arcus venosus dorsalis pedis; 6 - rete venosum dorsale pedis
See atlas, etc.

external iliac vein, v. iliaca externa, has no valves, is a continuation of the femoral vein (the inguinal ligament serves as the border between them), receives blood from all veins of the lower limb. The external iliac vein follows up next to the artery of the same name and adjoins the psoas major muscle on the medial side. At the level of the sacroiliac joint, it connects to the internal iliac vein ( v. iliaca interna), forming the common iliac vein ( v. iliaca communis). Directly above the inguinal ligament (almost within the vascular gap) into the external iliac vein flow: 1) inferior epigastric vein, v. epigastric inferior(a single vessel, the paired tributaries of which have numerous valves) and 2) a deep vein surrounding the ilium, v. circumflexa ilium profunda, its position and tributaries correspond to the branches of the artery of the same name; anastomoses with the iliac-lumbar vein - a tributary of the common iliac vein.

The veins of the lower limb are divided into superficial and deep.

Veins of the foot: dorsal digital veins, vv. digitales dorsales pedis(Fig. 152), start from the venous plexus of the fingers and flow into the dorsal venous arch of the foot ( arcus venosus dorsalis pedis). The medial and lateral sections of the arch give rise to the medial and lateral marginal veins. The continuation of the first of them is the great saphenous vein of the leg, and the second is the small saphenous vein of the leg. The plantar venous network is located on the plantar surface of the foot, rete venosum plantare(Fig. 153), which receives blood from numerous saphenous veins. It anastomoses with the deep veins of the fingers and metatarsus, as well as with the dorsal venous arch of the foot. Blood from the saphenous veins of the dorsal and plantar surfaces of the foot flows through the large and small saphenous veins of the leg. The deep veins of the plantar surface of the foot originate from the plantar digital veins ( vv. digitales plantares). Connecting with each other, they form the plantar metatarsal veins ( vv. metatarseae plantares), which flow into the plantar venous arch ( arcus venosus plantaris). From the arch through the medial and lateral plantar veins, blood flows into the posterior tibial veins.

Rice. 153. Small saphenous vein of the right lower limb and its tributaries.
1-v. saphena parva; 2 - rete venosum subcutaneum (BNA); 3 - branch connecting vv. saphenae parva et magna; 4 - rete venosum dorsale pedis; 5 - rete venosum plantare; 6-v. saphena magna.
See atlas, etc.

Great saphenous vein of the leg v. saphena magna(see Fig. 146, 152), has numerous valves; begins in front of the medial malleolus and, having received inflows from the plantar surface of the foot, follows next to the saphenous nerve along medial surface lower leg upwards, bends behind the medial epicondyle of the thigh, crosses the sartorius muscle and passes along the anteromedial surface of the thigh to the subcutaneous fissure ( hiatus saphenus). Here the vein goes around the falciform edge, perforates the ethmoid fascia and flows into the femoral vein. V. saphena magna receives numerous saphenous veins of the anteromedial surface of the lower leg and thigh; often (before flowing into the femoral vein), the saphenous veins of the external genital organs and the anterior wall of the abdomen flow into it: external pudendal veins, vv. pudendae externae; superficial vein surrounding the iliac bone v. circumflexa ilium superficialis; superficial epigastric vein, v. epigastria superficialis; superficial dorsal veins of the penis (clitoris), vv. dorsales penis (clitoridis) superficiales; anterior scrotal (labial) veins, vv. scrotales (labiales) anteriores.

Small saphenous vein of the leg, v. saphena parva(see p. 153), has many valves, is a continuation of the lateral marginal vein of the foot. It collects blood from the dorsal venous arch and from the saphenous veins of the plantar surface of the foot and heel region. The small saphenous vein follows up behind the lateral malleolus, is located in the groove between the lateral and medial heads of the gastrocnemius muscle, next to the medial skin branches of the lower leg (n. saphenus) penetrates into the popliteal fossa, where it flows into the popliteal vein. Numerous superficial veins of the posterolateral surface of the lower leg flow into the small saphenous vein. Its tributaries have numerous anastomoses with deep veins and with the great saphenous vein of the leg.

The deep veins of the lower extremity are equipped with numerous valves; they accompany the arteries of the same name in pairs. An exception is the deep vein of the thigh, v. profunda femoris];
pp.179-200;
pp.200-215;
pp.215-235;
pp.235-245.

It is an important component of our body. Without it, the vital activity of human organs and tissues is impossible. Blood nourishes our body with oxygen and is involved in all metabolic reactions. Vessels and veins, through which the "energy fuel" is transported, play an important role, so even a small capillary must work at full capacity.

Only the heart matters

In order to understand vascular system heart, you need to know a little about its structure. The four-chamber human heart is divided by a septum into 2 halves: left and right. Each half has an atrium and a ventricle. They are also separated by a septum, but with valves that allow the heart to pump blood. The venous apparatus of the heart is represented by four veins: two vessels (superior and inferior vena cava) flow into the right atrium, and two pulmonary vessels into the left.

The circulatory system in the heart is also represented by the aorta, and through the aorta, which departs from the left ventricle, blood enters all organs and tissues of the human body, except for the lungs. From the right ventricle through the pulmonary artery, blood moves through the supplying bronchi and alveoli of the lung. This is how blood circulates in our body.

Venous apparatus of the heart: superior vena cava

Since the heart is small in volume, the vascular apparatus is also represented by medium-sized, but thick-walled veins. In the anterior mediastinum of the heart is a vein formed by the fusion of the left and right brachiocephalic veins. It is called the superior vena cava and belongs to the systemic circulation. Its diameter reaches 25 mm, and its length is from 5 to 7.5 cm.

The superior vena cava is located deep enough in the pericardial cavity. To the left of the vessel is the ascending aorta, and to the right is the mediastinal pleura. Behind it, the anterior surface of the root of the right lung protrudes. and the right lung are located in front. Such a fairly close relationship is fraught with compression and, accordingly, a deterioration in blood circulation.

The superior vena cava empties into the right atrium at the level of the second rib and collects blood from the head, neck, upper chest, and arms. There is no doubt that this small vessel is of great importance in the human circulatory system.

What vessels are represented by the system of the superior vena cava?

The blood-carrying veins are located near the heart, so when the heart chambers relax, they seem to stick to it. Due to these peculiar movements, a strong negative pressure is created in the system.

Vessels included in the system of the superior vena cava:

• several veins extending from the walls of the abdomen;
• vessels that feed the neck and chest;
• veins of the shoulder girdle and arms;
• veins of the head and neck region.

Mergers and Confluences

What are the tributaries of the superior vena cava? The main tributaries can be called the brachiocephalic veins (right and left), which are formed as a result of the confluence of the internal jugular and subclavian veins and do not have valves. Due to constant low pressure there is a risk of air getting into them when injured. The left brachiocephalic vein runs behind the manubrium of the sternum and thymus, and behind it is the brachiocephalic trunk and the left carotid artery. The right blood thread of the same name starts its way from the sternoclavicular joint and is adjacent to the upper edge of the right pleura.

Also, the tributary is an unpaired vein, which is equipped with valves located at its mouth. This vein originates in the abdominal cavity, then passes along the right side of the vertebral bodies and through the diaphragm, following behind the esophagus to the point of confluence with the superior vena cava. It collects blood from the intercostal veins and chest organs. The unpaired vein lies on the right on the transverse processes of the thoracic vertebrae.

With anomalies of the heart, an additional left superior vena cava appears. In such cases, it can be considered an incapacitated inflow, which does not bear a burden on hemodynamics.

in system

The internal jugular vein is a fairly large vein that enters the system of the superior vena cava. It is she who collects blood from the veins of the head and part of the neck. It begins near the jugular foramen of the skull and, going down, forms the c and neurovascular bundle.

The tributaries of the jugular vein are divided into intracranial and extracranial. Intracranial include:

• meningeal veins;
• diploic veins (feeding the bones of the skull);
• vessels that carry blood to the eyes;
• labyrinth veins (inner ear);
• brain veins.

Diploic veins include: temporal (posterior and anterior), frontal, occipital. All of these veins carry blood to the sinuses of the dura mater and do not have valves.

Extracranial tributaries are:

• facial vein, carrying blood from the labial folds, cheeks, earlobes;
• mandibular vein.

The pharyngeal veins, superior thyroid veins, and lingual vein drain into the internal jugular vein in the middle third of the neck on the right.

Veins of the upper limbs included in the system

On the arm, the veins are divided into deep, lying in the muscles, and superficial, passing almost immediately under the skin.

Blood enters from the fingertips into the dorsal veins of the hand, followed by the venous plexus formed by superficial vessels. The cephalic and basilar veins are subcutaneous vessels of the arm. The main vein originates from the palmar arch and venous plexus of the hand on the back. It runs along the forearm and forms the median vein of the elbow, which is used for intravenous injections.

The veins of the palmar arches are divided into two deep ulnar and radial vessels, which merge near the elbow joint and two brachial veins are obtained. Then the brachial vessels pass into the axillary. continues axillary and has no branches. It is connected to the fascia and periosteum of the first rib, due to which its lumen increases when the arm is raised. The blood supply of this vein is equipped with two valves.

Vessels of the chest

The intercostal veins lie in the intercostal spaces and collect blood from the chest cavity and partially the anterior abdominal wall. The tributaries of these vessels are the spinal and intervertebral veins. They are formed from the vertebral plexuses located inside the spinal canal.

The vertebral plexuses are vessels that repeatedly anastomose with each other, extending from the occipital foramen to the upper part of the sacrum. In the upper part of the spinal column, small plexuses develop into larger ones and flow into the veins of the spine and occiput.

Causes of compression of the superior vena cava

The causes of such an ailment as superior vena cava syndrome are such pathological processes as:

• oncological diseases (adenocarcinoma, lung cancer);
• metastases in breast cancer;
• tuberculosis;
• retrosternal goiter thyroid gland;
• syphilis;
• soft tissue sarcoma and others.

Often, compression occurs due to the germination of a malignant tumor in the wall of the vein or its metastasis. Thrombosis can also cause an increase in pressure in the lumen of the vessel up to 250-500 mm Hg, which is fraught with rupture of the vein and death of a person.

How does the syndrome manifest itself?

Symptoms of the syndrome can develop instantly without precursors. This occurs when the superior vena cava becomes blocked by an atherosclerotic thrombus. In most cases, symptoms develop gradually. The patient has:

• headache and dizziness;
• cough with increasing shortness of breath;
• pain in the chest;
• nausea and dysphagia;
• change in facial features;
• fainting;
• swelling of the veins in the chest and neck;
• swelling and puffiness of the face;
• cyanosis of the face or chest.

To diagnose the syndrome, several studies are necessary. Well-established radiography and Doppler ultrasonography. With their help, it is possible to differentiate diagnoses and prescribe appropriate surgical treatment.

4. Venous system: general plan of the structure, anatomical features of the veins, venous plexuses. Factors that ensure the centripetal movement of blood in the veins.

5. The main stages of the development of the heart.

6. Features of the fetal circulation and its changes after birth.

7. Heart: topography, structure of chambers and valvular apparatus.

8. The structure of the walls of the atria and ventricles. conduction system of the heart.

9. Blood supply and innervation of the heart. Regional lymph nodes (!!!).

10. Pericardium: structure, sinuses, blood supply, venous and lymphatic outflow, innervation (!!!).

11. Aorta: divisions, topography. Branches of the ascending aorta and the aortic arch.

12. Common carotid artery. External carotid artery, its topography and general characteristics of the lateral and terminal branches.

13. External carotid artery: anterior group of branches, their topography, areas of blood supply.

14. External carotid artery: medial and terminal branches, their topography, areas of blood supply.

15. Maxillary artery: topography, branches and areas of blood supply.

16. Subclavian artery: topography, branches and areas of blood supply.

17. Blood supply to the brain and spinal cord (internal carotid and vertebral arteries). Formation of the arterial circle of the brain, its branches.

18. Internal jugular vein: topography, intra and extracranial tributaries.

19. Cerebral veins. Venous sinuses of the dura mater, their connections with the external system of veins (deep and superficial veins of the face), emissary and diploic veins.

20. Superficial and deep veins of the face, their topography, anastomoses.

21. Superior vena cava and brachiocephalic veins, their formation, topography, tributaries.

22. General principles of the structure and function of the lymphatic system.

23. Thoracic duct: formation, parts, topography, tributaries.

24. Right lymphatic duct: formation, parts, topography, places where it flows into the venous bed.

25. Ways of lymph outflow from the tissues and organs of the head and regional lymph nodes.

26. Ways of outflow of lymph from the tissues and organs of the neck and regional lymph nodes.

21. Superior vena cava and brachiocephalic veins, their formation, topography, tributaries.

Superior vena cava (s.cdvasuperior) - this is a short valveless vessel with a diameter of 21-25 mm and a length of 5-8 cm, which is formed as a result of the confluence of the right and left brachiocephalic veins behind the junction of the cartilage of the first right rib with the sternum (Fig. 109). This vein follows vertically down and at the level of the connection of the third right cartilage with the sternum flows into the right atrium. In front of the vein are the thymus and the mediastinal part of the right lung covered with pleura. The mediastinal (mediastinal) pleura is adjacent to the vein to the right, and the ascending aorta is to the left. With its posterior wall, the superior vena cava is in contact with the anterior surface of the root of the right lung. The unpaired vein flows into the superior vena cava on the right, and the small mediastinal and pericardial veins on the left. The superior vena cava collects blood from three groups of veins: veins of the walls of the chest and partially abdominal cavities, veins of the head and neck, and veins of both upper limbs, i.e. from those areas that are supplied with blood by the branches of the arch and the thoracic part of the aorta (Table 16).

Unpaired vein (s.azygos) is a continuation in the thoracic cavity right ascending lumbar vein(v. lumb & lis ascendens dextra), which passes between the muscle bundles of the right leg of the lumbar part of the diaphragm into the posterior mediastinum and on its way anastomoses with the right lumbar veins that flow into the inferior vena cava. Behind and to the left of the unpaired vein are the vertebral column, the thoracic aorta and thoracic duct, as well as the right posterior intercostal arteries. The esophagus lies in front of the vein. At the level of the IV-V thoracic vertebrae, the unpaired vein goes around the root of the right lung behind and above, then goes forward and down and flows into the superior vena cava. There are two valves at the mouth of the unpaired vein. The semi-unpaired vein and the veins of the posterior wall of the chest cavity flow into the unpaired vein on its way to the superior vena cava: right top nya intercostal vein; posterior intercostal veins, as well as veins of the organs of the chest cavity: esophageal, bronchial, pericardial and mediastinal veins.

Semi-jeparous vein ( v . hemiazygos ), which is sometimes called the left, or small unpaired, vein, thinner than the unpaired vein, since only 4-5 lower left posterior intercostal veins flow into it. The semi-unpaired vein is a continuation of the left ascending lumbar vein(v. lumbdis ascendens sinistra), passes between the muscle bundles of the left leg of the diaphragm into the posterior mediastinum, adjacent to the left surface of the thoracic vertebrae. To the right of the semi-unpaired vein are the thoracic aorta, behind the left posterior intercostal arteries. At the level of VII-X thoracic vertebrae, the semi-unpaired vein turns sharply to the right, crosses the spinal column in front, is located behind the aorta, esophagus and thoracic duct) and flows into the unpaired vein. The accessory semi-unpaired vein flows into the semi-unpaired vein from top to bottom.(v. hemiazygos accessoria), receiving 6-7 superior intercostal veins(I- VII), as well as the esophageal and mediastinal veins. The most significant tributaries of the unpaired and semi-unpaired veins are the posterior intercostal veins, each of which is connected at its anterior end to the anterior intercostal vein, a tributary of the internal thoracic vein. The presence of such connections of the veins creates the possibility of outflow of venous blood from the walls of the chest cavity back into the unpaired and semi-unpaired veins and forward into the internal thoracic veins.

Posterior intercostal veins (w. intercostdles posteriores) are located in the intercostal spaces next to the arteries of the same name (in the groove of the corresponding rib). These veins collect blood from the tissues of the walls of the chest cavity and partly from the anterior abdominal wall (lower posterior intercostal veins). The dorsal vein empties into each of the posterior intercostal veins.(v. dorsalis), which is formed in the skin and muscles of the back, and the intervertebral vein(v. intervertebralis), formed from the veins of the external and internal vertebral plexuses. A spinal branch flows into each intervertebral vein (r.spinalis), which, along with other veins (vertebral, lumbar and sacral) is involved in the outflow of venous blood from the spinal cord.

Internal (anterior and posterior) vertebral venous plexuses (plexus venosi vertebrals interni, anterior et post6 rior) are located inside the spinal canal (between the hard shell of the spinal cord and the periosteum) and are represented by repeatedly anastomosing veins (Fig. 110). The plexuses extend from the foramen magnum to the top of the sacrum. The spinal veins and veins of the spongy substance of the vertebrae flow into the internal vertebral plexuses. From these plexuses, blood flows through the intervertebral veins passing through the intervertebral foramina (next to the spinal nerves) into the unpaired, semi-unpaired and accessory semi-unpaired veins. Blood from the internal plexuses also flows intoexternal (anterior and posterior) venous vertebral plexuses (plexus venosi vertebrals externi, anterior et posterior), which are located on the anterior surface of the vertebrae, and also braid their arcs and processes. From the external vertebral plexuses, blood flows into the posterior intercostal, lumbar and sacral veins.(vv. intercostdles posteriores, lumbales et sacrales), as well as directly into the unpaired, semi-unpaired and additional semi-unpaired veins. At the level of the upper part of the spinal column, the veins of the plexuses flow into the vertebral and occipital veins.(vv. vertebrals et occipitdles).

Brachiocephalic veins (right and left) (vv. brachiocephdlicae, dextra et sinistra) valveless, are the roots of the superior vena cava. They collect blood from the organs of the head and neck and upper extremities. Each brachiocephalic vein is formed from two veins - the subclavian and internal jugular (Fig. 111).

Left brachiocephalic vein formed behind the left sternoclavicular joint. The vein has a length of 5-6 cm, follows from the place of its formation obliquely down and to the right behind the handle of the sternum and thymus. Behind this vein are the brachiocephalic trunk, the left common carotid and subclavian arteries. At the level of the cartilage of the right I rib, the left brachiocephalic vein connects with the right vein of the same name, forming the superior vena cava.

Right brachiocephalic vein 3 cm long is formed behind the right sternoclavicular joint. Then the vein descends almost vertically behind the right edge of the sternum and is adjacent to the dome of the right pleura.

Small veins from the internal organs flow into each brachiocephalic vein: thymic veins (vv. thymicae); pericardial veins (vv, pericardidcae); pericardial phrenic veins (w. pericardial ophreiiicae); bronchial veins (vv. bronchidles); esophageal veins (vv. oesophagedles); mediastinal veins (vv. mediastinales) - from the lymph nodes and connective tissue of the mediastinum. Larger tributaries of the brachiocephalic veins are the inferior thyroid veins (vv. thyroidede inferiores, only 1-3), through which blood flows from unpaired thyroid plexus(plexus thyroideus impar), and the inferior laryngeal vein (v. laryngea inferior), which brings blood from the larynx and anastomoses with the superior and middle thyroid veins.

Vertebral vein(v. vertebrdlis) passes along with the vertebral artery through the transverse openings of the cervical vertebrae to the brachiocephalic vein, taking on its way the veins of the internal vertebral plexuses.

deep jugular vein(v. cervicalis profunda) starts from the external vertebral plexuses, collects blood from the muscles and fascia located in the occipital region. This vein passes behind the transverse processes of the cervical vertebrae and flows into the brachiocephalic vein near the mouth of the vertebral vein or directly into the vertebral vein.

Internal thoracic vein(v. thoracica interna) steam room, accompanies the internal thoracic artery. The roots of the internal thoracic veins are the superior epigastric vein (v. epigastrica superioris) and the musculophrenic vein (v. musculophrenica). The superior epigastric vein anastomoses in the thickness of the anterior abdominal wall with the inferior epigastric vein, which flows into the external iliac vein. The anterior intercostal veins (w. intercostales anteriores) lying in the anterior intercostal spaces flow into the internal thoracic vein, which anastomose with the posterior intercostal veins that flow into the unpaired or semi-unpaired vein.

The highest intercostal vein (v. intercostalis suprema) flows into each brachiocephalic vein, right and left, collecting blood from 3-4 upper intercostal spaces.

Superior vena cava - short vessel 5-8 cm long and 21-25 mm wide. It is formed by the confluence of the right and left brachiocephalic veins. The superior vena cava receives blood from the walls of the chest and abdominal cavities, organs of the head and neck, and upper limbs.

Veins of the head and neck. The main venous collector from the organs of the head and neck is the internal jugular vein and partially the external jugular vein (Fig. 94).

Rice. 94. Veins of the head and face:

1 - occipital vein; 2 - pterygoid (venous) plexus; 3 - maxillary vein; 4 - submandibular vein; 5 - internal jugular vein; 6 - external jugular vein; 7 - mental vein; 8 - facial vein; 9 - frontal vein; 10- superficial temporal vein

Internal jugular vein - a large vessel that receives blood from the head and neck. It is a direct continuation of the sigmoid sinus of the dura mater; originates from the jugular foramen of the skull, goes down and, together with the common carotid artery and the vagus nerve forms the neurovascular bundle of the neck. All tributaries of this vein are divided into intracranial and extracranial.

TO intracranial include cerebral veins that collect blood from the cerebral hemispheres; meningeal veins - blood comes from the meninges; diploic veins - from the bones of the skull; eye veins - blood comes from the organs of vision and nose; labyrinth veins - from inner ear. These veins carry blood to the venous sinuses (sinuses) of the hard shell of the brain. The main sinuses of the dura mater are superior sagittal sinus, which runs along the upper edge of the falx cerebrum and flows into the transverse sinus; inferior sagittal sinus runs along the lower edge of the falx cerebrum and flows into the straight sinus; straight sine connects with the transverse; the cavernous sinus is located around the Turkish saddle; transverse sinus laterally enters the sigmoid sinus, which passes into the internal jugular vein.

Sinuses of the dura mater with emissary veins connect with the veins of the outer covering of the head.

TO extracranial tributaries internal jugular vein are facial vein - collects blood from the face and oral cavity; submandibular vein - receives blood from the scalp, auricle, masticatory muscles, part of the face, nose, lower jaw.

The pharyngeal veins, lingual, and superior thyroid veins flow into the internal jugular vein in the neck. They collect blood from the walls of the pharynx, tongue, floor of the mouth, submandibular salivary glands, thyroid gland, larynx, sternocleidomastoid muscle.

External jugular vein formed as a result of the connection of its two tributaries: 1) the confluence of the occipital and posterior ear veins; 2) anastomosis with the submandibular vein. Collects blood from the skin of the occipital and behind the ear region. The suprascapular vein, anterior jugular vein and transverse veins of the neck flow into the external jugular vein. These vessels collect blood from the skin of the same area.

Anterior jugular vein is formed from the small veins of the mental region, penetrates into the interfascial suprasternal space, in which the right and left anterior jugular veins, connecting, form jugular venous arch. The latter flows into the external jugular vein of the corresponding side.

subclavian vein - unpaired trunk, is a continuation of the axillary vein, merges with the internal jugular vein, collects blood from the upper limb.

Veins of the upper limb. Allocate superficial and deep veins of the upper limb. Superficial veins, connecting with each other, form venous networks, from which two main saphenous veins of the arm are then formed: lateral saphenous vein of the arm located on the side of the radius and flows into the axillary vein and medial saphenous vein of the arm located on the ulnar side and flows into the brachial vein. In the elbow bend, the lateral and medial saphenous veins are connected by a short intermediate vein of the elbow.

The deep veins of the upper limb are deep palmar veins. They accompany the arteries of the same name in two, form superficial and deep venous arches. The palmar digital and palmar metacarpal veins flow into the superficial and deep palmar venous arches, which then pass into the deep veins of the forearm - the paired ulnar and radial veins. Along the way, veins from muscles and bones join them, and in the region of the cubital fossa they form two brachial veins. The latter take blood from the skin and muscles of the shoulder, and then, not reaching the axillary region, at the level of the tendon of the widest muscle of the back, they are connected into one trunk - axillary vein. Veins flow into this vein from the muscles of the shoulder girdle and shoulder, and also partially from the muscles of the chest and back.

At the level of the outer edge of the 1st rib, the axillary vein passes into subclavian. It is joined by the non-permanent transverse vein of the neck, the subscapular vein, as well as the small thoracic and dorsal scapular veins. The confluence of the subclavian vein with the internal jugular vein on each side is called the venous angle. As a result of this connection, brachiocephalic veins, where the veins of the thymus, mediastinum, pericardial sac, esophagus, trachea, neck muscles, spinal cord, etc. flow. Further, having joined, the brachiocephalic veins form the main trunk - superior vena cava. It is joined by the veins of the mediastinum, the pericardial sac and unpaired vein, which is a continuation of the right ascending lumbar vein. The unpaired vein collects blood from the walls of the abdominal and chest cavities (Fig. 95). It empties into an unpaired vein semi-azygous vein, to which the veins of the esophagus, mediastinum, partially posterior intercostal veins join; they are a continuation of the left ascending lumbar vein.

Inferior vena cava system

The system of the inferior vena cava is formed from the joints that collect blood from the lower extremities, walls and organs of the pelvis and abdominal cavity.

inferior vena cava formed by the union of the left and right common iliac veins. This thickest venous trunk is located retroperitoneally. It originates at the level of IV-V lumbar vertebrae, is located to the right of abdominal aorta, goes up to the diaphragm and through the opening of the same name - into the posterior mediastinum. Penetrates into the pericardial cavity and flows into the right atrium. Along the way, parietal and visceral vessels join the inferior vena cava.

Parietal venous tributaries include lumbar veins(3-4) on each side, collect blood from the venous plexus of the spine, muscles and skin of the back; anastomose with the ascending lumbar vein; inferior phrenic veins(right and left) - blood comes from the lower surface of the diaphragm; drain into the inferior vena cava.

The group of visceral tributaries includes testicular (ovarian) veins, collect blood from the testicle (ovary); renal veins - from the kidney; adrenal - from the adrenal glands; hepatic - carry blood away from the liver.

Venous blood from the lower extremities, walls and organs of the pelvis is collected in two large venous vessels: the internal iliac and external iliac veins, which, having joined at the level of the sacroiliac joint, form the common iliac vein. Both common iliac veins then merge into the inferior vena cava.

Internal iliac a vein is formed from veins that collect blood from the pelvic organs and belong to the parietal and visceral tributaries.

To the group parietal tributaries includes the superior and inferior gluteal veins, obturator, lateral sacral and iliac-lumbar veins. They collect blood from the muscles of the pelvis, thigh, and abdomen. All veins have valves. TO visceral tributaries include the internal genital vein - collects blood from the perineum, external genital organs; bladder veins - blood comes from the bladder, vas deferens, seminal vesicles, prostate (in men), vagina (in women); lower and middle rectal veins - collect blood from the walls of the rectum. Visceral tributaries, connecting with each other, form venous plexuses around the pelvic organs (bladder, prostate, rectum).

The veins of the lower limb are aimed into superficial and deep, which are interconnected by anastomoses.

In the area of ​​the foot, the saphenous veins form the plantar and dorsal venous networks of the foot, into which the digital veins flow. From the venous networks, the dorsal metatarsal veins are formed, which give rise to the large and small saphenous veins of the leg.

Great saphenous vein of the leg is a continuation of the medial dorsal metatarsal vein, along the way it receives numerous superficial veins from the skin and flows into the femoral vein.

Small saphenous vein of the leg It is formed from the lateral part of the subcutaneous venous network of the rear of the foot, flows into the popliteal vein, collects blood from the saphenous veins of the plantar and dorsal surfaces of the foot.

Deep veins of the lower limb are formed by the digital veins, which merge into the plantar and dorsal metatarsal veins. The latter flow into the plantar and dorsal venous arches of the foot. From the plantar venous arch, blood flows through the plantar metatarsal veins into the posterior tibial veins. From the dorsal venous arch, blood enters the anterior tibial veins, which along the way collect blood from the surrounding muscles and bones and, when combined, form the popliteal vein.

Popliteal vein receives small knee veins, small saphenous vein and passes into the femoral vein.

femoral vein, rising up, goes under the inguinal ligament and passes into the external iliac vein.

The deep vein of the thigh flows into the femoral vein; veins surrounding the femur; superficial epigastric veins; external genital veins; great saphenous vein of the leg. They collect blood from the muscles and fascia of the thigh and pelvic girdle, the hip joint, the lower part of the abdominal wall, and the external genitalia.

portal vein system

From unpaired organs of the abdominal cavity, except for the liver, blood is first collected in the portal vein system, through which it goes to the liver, and then through the hepatic veins to the inferior vena cava.

Portal vein(Fig. 96) - a large visceral vein (length 5-6 cm, diameter 11-18 mm), is formed by connecting the inferior and superior mesenteric and splenic veins. The veins of the stomach, small and large intestine, spleen, pancreas and gallbladder flow into the portal vein. Then the portal vein goes to the gate of the liver and enters its parenchyma. In the liver, the portal vein is divided into two branches: the right and the left, each of which, in turn, is divided into segmental and smaller ones. Inside the lobules of the liver, they branch into wide capillaries (sinusoids) and flow into the central veins, which pass into the sublobular veins. The latter, connecting, form three or four hepatic veins. Thus, blood from the organs of the digestive tract passes through the liver, and then only enters the system of the inferior vena cava.

Superior mesenteric vein goes to the roots of the mesentery of the small intestine. Its tributaries are the veins of the jejunum and ileum, pancreatic, pancreatoduodenal, iliac-colic, right gastroepiploic, right and middle colic veins and the vein of the appendix. The superior mesenteric vein receives blood from the above organs.

Rice. 96. Portal vein system:

1 - superior mesenteric vein; 2 - stomach; 3 - left gastroepiploic vein; 4 - left gastric vein; 5- spleen; 6- tail of the pancreas; 7- splenic vein; 8- inferior mesenteric vein; 9- descending colon; 10 - rectum; 11 - inferior rectal vein; 12- middle rectal vein; 13- superior rectal vein; 14 - ileum; 15 - ascending colon; 16 - head of the pancreas; 17, 23- right gastroepiploic vein; 18- portal vein; 19- gallbladder vein; 20 - gallbladder; 21 - duodenum; 22 - liver; 24- pyloric vein

splenic vein collects blood from the spleen, stomach, pancreas, duodenum and greater omentum. The tributaries of the splenic vein are the short gastric veins, the pancreatic vein, and the left gastroepiploic vein.

Inferior mesenteric vein is formed as a result of the confluence of the superior rectal vein, left colic and sigmoid veins; it collects blood from the walls of the upper rectum, sigmoid colon, and descending colon.

lymphatic system

The lymphatic system is part of cardio-vascular system(Fig. 97). Through the lymphatic system, water, proteins, fats, and metabolic products return from the tissues to the circulatory system.

Rice. 97. Lymphatic system (diagram):

1,2 - parotid lymphatic minds; 3 - cervical nodes; 4 - thoracic duct; 5, 14 - axillary lymph nodes; 6, 13 - elbow lymph nodes; 7, 9- inguinal lymph nodes; 8 - superficial lymphatic vessels of the leg; 10 - iliac nodes; 11 - mesenteric nodes; 12 - cistern of the thoracic duct; 15 - subclavian nodes; 16 - occipital nodes; 17- submandibular nodes

The lymphatic system performs a number of functions: 1) maintains the volume and composition of tissue fluid; 2) maintains a humoral connection between the tissue fluid of all organs and tissues; 3) absorption and transfer of nutrients from the digestive tract to the venous system; 4) transfer to the bone marrow and to the site of injury of migrating lymphocytes, plasma cells. Cells are transported through the lymphatic system malignant neoplasms(metastases), microorganisms.

The human lymphatic system consists of lymphatic vessels, lymph nodes, and lymphatic ducts.

The beginning of the lymphatic system is lymph capillaries. They are found in all organs and tissues of the human body, except for the brain and spinal cord and their membranes, skin, placenta, spleen parenchyma. The walls of the capillaries are thin single-layer epithelial tubes with a diameter of 10 to 200 microns, have a blind end. They stretch easily and can expand 2-3 times.

When several capillaries merge, they form lymph vessel. Here is the first valve. Depending on the location of the lymphatic vessels are divided into superficial and deep. Through the vessels, lymph goes to the lymph nodes that correspond to a given organ or part of the body. Depending on where the lymph is collected from, visceral, somatic (parietal) and mixed lymph nodes are distinguished. The former collect lymph from the internal organs (tracheobronchial, etc.); the second - from the musculoskeletal system (popliteal, elbow); still others - from the walls of hollow organs; the fourth - from the deep structures of the body (deep cervical nodes).

The vessels that carry lymph to the node are called bringing and the vessels that come out of the gates of the node - enduring lymphatic vessels.

Large lymphatic vessels form lymphatic trunks, which, when merged, form lymphatic ducts flowing into the venous nodes or into the terminal sections of the veins that form them.

There are six such large lymphatic ducts and trunks in the human body. Three of them (thoracic duct, left jugular and left subclavian trunks) flow into the left venous angle, three others (right lymphatic duct, right jugular and right subclavian trunks) into the right venous angle.

thoracic duct is formed in the abdominal cavity, behind the peritoneum, at the level of the XII thoracic and II lumbar vertebrae as a result of the fusion of the right and left lumbar lymphatic trunks. Its length is 20-40 cm, it collects lymph from the lower extremities, the walls and organs of the pelvis, the abdominal cavity and the left half of the chest. From the abdominal cavity, the thoracic duct passes through the aortic opening into the chest cavity, and then exits into the neck region and opens into the left venous angle or into the terminal sections of the veins that form it. It flows into the cervical part of the duct bronchomediastinal trunk, which collects lymph from the left half of the chest; left subclavian trunk carries lymph from the left hand; left jugular trunk comes from the left side of the head and neck. On the path of the thoracic duct there are 7-9 valves that prevent the reverse flow of lymph.

From the right half of the head, neck, upper limb, organs of the right half of the chest, lymph collects right lymphatic duct. It is formed from the right subclavian, right bronchomediastinal and jugular trunks and flows into the right venous angle.

Lymphatic vessels and nodes of the lower limb are divided into superficial and deep. Superficial vessels collect lymph from the skin and subcutaneous tissue of the foot, lower leg and thigh. They fall into the superficial inguinal The lymph nodes that are below the inguinal ligament. In the same nodes, lymph flows from the anterior abdominal wall, gluteal region, external genitalia, perineum and part of the pelvic organs.

In the popliteal fossa are popliteal lymph nodes, which collect lymph from the skin of the foot, lower leg. The efferent ducts of these nodes empty into deep inguinal lymph nodes.

deep lymphatic vessels they collect lymph from the foot, lower leg into the popliteal lymph nodes, and from the thigh tissues into the deep inguinal nodes, the efferent vessels of which flow into the external iliac nodes.

Depending on the location pelvic lymph nodes divided into parietal and visceral. The first group includes external, internal and common iliac nodes, which collect lymph from the walls of the pelvis. Visceral lymph nodes in relation to the pelvic organs are periurinary, parauterine, paravaginal, pararectal and collect lymph from the corresponding organs.

The efferent vessels of the internal and external iliac nodes reach common iliac lymph nodes, from which the lymph goes to the lumbar nodes.

IN abdominal lymph nodes lymph is collected from the parietal and visceral lymph nodes and vessels of the abdominal cavity, lower back.

The efferent lymphatic vessels of the lumbar lymph nodes form the right and left lumbar trunks, which give rise to the thoracic duct.

Lymphatic vessels and nodes of the chest cavity collect lymph from the walls of the chest and organs located in it.

Depending on the topography of organs, lymph nodes are distinguished parietal(sternal, intercostal, superior diaphragmatic) and visceral(anterior and posterior mediastinal, bronchopulmonary, lower and upper tracheobronchial). They collect lymph from the relevant organs.

In the head area, lymph flows from the occipital, mastoid, superficial and deep parotid, facial, chin, submandibular lymph nodes.

By topographic location neck lymph nodes are divided into cervical and lateral cervical, as well as superficial and deep. Lymph comes to them from adjacent organs.

Connected, the lymphatic vessels of the neck on each side form jugular trunk. On the right, the jugular trunk joins the right lymphatic duct or independently flows into the venous angle, and on the left - to the thoracic duct.

In the upper limb, the lymph first collects through the superficial and deep vessels into the regional elbow and axillary lymph nodes. They are in the pits of the same name. Elbow knots divided into superficial and deep. Axillary lymph nodes also divided into superficial and deep. By localization, the lymph nodes in the axillary region are divided into medial, lateral, posterior, lower, central and apical. Superficial lymphatic vessels, accompanying the saphenous veins of the upper extremities, form the medial, middle and lateral group.

Coming out of the deep axillary lymph nodes, the vessels form the subclavian trunk, which flows into the thoracic duct on the left, and on the right into the right lymphatic duct.

The lymph nodes are peripheral organs immune system, which act as biological and mechanical filters and are usually located around blood vessels, usually in groups of several to ten knots or more.

Lymph nodes are pinkish-gray in color, round, ovoid, bean-shaped and ribbon-shaped, their length ranges from 0.5 to 30-50 mm (Fig. 98).

Rice. 98. The structure of the lymph node:

1 - capsule; 2 - trabecula; 3 - crossbar; 4 - cortex; 5 - follicles; 6- afferent lymphatic vessels; 7- medulla; 8- efferent lymphatic vessels; 9- gate of the lymph node

Each lymph node is covered with a connective tissue capsule from the outside. The lymph node on one side has veins and efferent lymphatic vessels. The afferent vessels approach the node from the convex side. Inside the node, thin partitions depart from the capsule and are interconnected in the depth of the node.

On the section of the node, peripheral dense cortical substance, which consists of cortical and paracortical zones, and the central medulla are visible. In the cortex and medulla, B- and T-lymphocytes are formed and a leukocyte factor is produced, which stimulates cell reproduction. Mature lymphocytes enter the sinuses of the nodes, and then are carried out with the lymph into the outlet vessels.

Hematopoietic organs

The bone marrow is the organ that produces blood cells. It forms and reproduces stem cells, which give rise to all types of blood cells and the immune system. Therefore, the bone marrow is also called the immune organ. Stem cells have a great ability to multiply and form a self-sustaining system.

As a result of numerous complex transformations and differentiation in three directions (erythropoiesis, granulopoiesis and thrombopoiesis), stem cells become shaped elements. In stem cells, cells of the immune system are also formed - lymphocytes, and from the latter - plasma cells (plasmocytes).

Allocate red bone marrow, which is located in the spongy substance of flat and short bones, and yellow marrow, which fills the cavities of the diaphysis of long tubular bones.

The total bone marrow mass of an adult is about 2.5-3.0 kg, or 4.5-4.7% of body weight.

The red bone marrow consists of myeloid tissue, which also includes reticular and hematopoietic tissue, and yellow bone marrow consists of adipose tissue, which replaced the reticular tissue. With significant blood loss, the yellow bone marrow is again replaced by red bone marrow.

Spleen(lien, splen) performs the functions of a peripheral organ of the immune system. It is located in the abdominal cavity, in the region of the left hypochondrium, at the level from IX to XI ribs. The weight of the spleen is about 150-195 g, the length is 10-14 cm, the width is 6-10 cm and the thickness is 3-4 cm. splenic ligaments. It has a red-brown color, soft texture. Connective tissue partitions - trabeculae, between which there is a parenchyma, depart from the fibrous membrane inside the organ. The latter is formed by white and red pulp. The white pulp consists of splenic lymph nodes and lymphoid tissue around the intraorgan arteries. The red pulp is formed by loops of reticular tissue filled with erythrocytes, lymphocytes, macroorganisms and other cellular elements, as well as venous sinuses.

On the concave surface are the gates of the spleen, they are the vessels and nerves.

In the spleen, the destruction of erythrocytes occurs, as well as the differentiation of T- and B-lymphocytes.

thymus(thymus), or thymus, refers to the central organs of lymphocytopoiesis and immunogenesis. In the thymus, stem cells coming from the bone marrow. after a series of transformations, they become T-lymphocytes. The latter are responsible for the reactions of cellular immunity. Then T-lymphocytes enter the blood and lymph, leave the thymus and pass into the thymus-dependent zones of the peripheral organs of immunogenesis. In the thymus, stromal epithelial cells produce thymosin(hemopoietic factor), which stimulates the proliferation of lymphoblasts. In addition, other biologically active substances are produced in the thymus. active substances(factors with properties of insulin, calcitonin, growth factors).

The thymus is an unpaired organ composed of the left and right lobe connected by loose cellulose. From above, the thymus gland narrows, and expands from below. Left lobe in many cases it can be longer than the right one.

The thymus is located in the anterior part of the upper mediastinum, in front of the upper part of the pericardium, the aortic arch, the left brachiocephalic and superior vena cava. The right and left mediastinal pleura adjoin the thymus on the sides. The anterior surface of the thymus connects to the sternum. The organ is covered with a thin connective tissue capsule, from which partitions extend inward, dividing the substance of the gland into small lobules. The parenchyma of the organ consists of the peripheral part of the cortex and the central part of the medulla. The thymus stroma is represented by reticular tissue. Between the fibers and cells of the reticular tissue are thymus lymphocytes (thymocytes), as well as multi-layered epithelial cells (epithelio-reticulocytes). In addition to the immunological function and the function of blood formation, the thymus is also characterized by endocrine activity.

The superior vena cava is a short thin-walled vein with a diameter of 20 to 25 mm, located in the anterior mediastinum. Its length varies on average from five to eight centimeters. The superior vena cava belongs to the veins of the systemic circulation and is formed by the confluence of two (left and right) brachiocephalic veins. It collects venous blood from the head, upper chest, neck, and arms and empties into the right atrium. The only tributary of the superior vena cava is the azygos vein. Unlike many other veins, this vessel does not have valves.

The superior vena cava is directed downward and enters the pericardial cavity at the level of the second rib, and a little lower flows into the right atrium.

The superior vena cava is surrounded by:

• Left - aorta (ascending part);
• Right - mediastinal pleura;
• Ahead - thymus (thymus gland) and right lung (mediastinal part covered with pleura);
• Behind - the root of the right lung (anterior surface).

Superior vena cava system

All vessels included in the system of the superior vena cava are located close enough to the heart, and during relaxation, they are under the influence of the suction action of its chambers. Also affects them during respiratory movements rib cage. Due to these factors, a sufficiently strong negative pressure is created in the system of the superior vena cava.

The main tributaries of the superior vena cava are the avalvular brachiocephalic veins. They also always have very low pressure, so there is a risk of air entering if they are injured.

The system of the superior vena cava is made up of veins:

• Neck and head areas;
• The chest wall, as well as some veins of the abdominal walls;
• Upper shoulder girdle and upper limbs.

Venous blood from the chest wall enters the inflow of the superior vena cava - the unpaired vein, which absorbs blood from the intercostal veins. The unpaired vein has two valves located at its mouths.

The external jugular vein is located at the level of the angle of the mandible under auricle. This vein collects blood from tissues and organs located in the head and neck. The posterior ear, occipital, suprascapular and anterior jugular veins flow into the external jugular vein.

The internal jugular vein originates near the jugular foramen of the skull. This vein, together with the vagus nerve and the common carotid artery, forms a bundle of vessels and nerves of the neck, and also includes the veins of the brain, meningeal, ophthalmic, and diploic veins.

Vertebral venous plexuses, which are part of the superior vena cava system, are divided into internal (passing inside the spinal canal) and external (located on the surface of the vertebral bodies).

Syndrome of compression of the superior vena cava

The syndrome of compression of the superior vena cava, manifested as a violation of its patency, can develop for several reasons:

• With the progression of the development of oncological diseases. With lung cancer and lymphomas, lymph nodes are often affected, in the immediate vicinity of which the superior vena cava passes. Also, metastases of breast cancer, soft tissue sarcomas, melanoma can lead to impaired patency;
• Against the background of cardiovascular insufficiency;
• With the development of retrosternal goiter against the background of the pathology of the thyroid gland;
• With the progression of some infectious diseases such as syphilis, tuberculosis and histioplasmosis;
• In the presence of iatrogenic factors;
• With idiopathic fibrous mediastinitis.

The syndrome of compression of the superior vena cava, depending on the causes that caused it, can progress gradually or develop quite quickly. The main symptoms of the development of this syndrome include:

• swelling of the face;
• Cough;
• convulsive syndrome;
• Headache;
• nausea;
• Dizziness;
• Dysphagia;
• Change in facial features;
• Drowsiness;
• Shortness of breath
• fainting;
• Pain in the chest;
• Swelling of the veins of the chest, and in some cases of the neck and upper limbs;
• Cyanosis and plethora of the upper chest and face.

To diagnose the syndrome of compression of the superior vena cava, as a rule, an x-ray is performed, which allows to identify the pathological focus, as well as to determine the boundaries and extent of its spread. In addition, in some cases, carry out:

• Computed tomography - to obtain more accurate data on the location of the mediastinal organs;
• Phlebography - to assess the extent of the focus of the disorder and conduct differential diagnosis between vascular and extravascular lesions.

After the studies, taking into account the rate of progression of the pathological process, the issue of conducting drug treatment, chemotherapy or radiation therapy or surgery.

In cases where the cause of changes in the vein is thrombosis, thrombolytic therapy is carried out, followed by the appointment of anticoagulants (for example, heparin sodium or therapeutic doses warfarin).