Lymphatic system (cont d)

Transcription

1 Circulatory System Objectives Understand the roles of the cardiovascular and lymphatic systems and their relationship to each other Know the tissue layers that characterize blood vessels Know the anatomical and functional differences between arteries, veins and capillaries Distinguish systemic and pulmonary circulation and portal circulation Describe differences in adult and fetal circulation with respect to the hepatic portal and pulmonary systems Know the cellular components of blood Know where hematopoeisis occurs and where blood cells are removed from circulation Know the relationship of cerebrospinal fluid (CSF) to blood Relate the function of the following organs to the circulatory system: spleen, thymus, lymph nodes, tonsils, carotid bodies, hypothalamus, brown fat, lungs, kidneys, liver, bone marrow, endocrine glands, choroid plexus

2 Major divisions of the circulatory system Cardiovascular system functions distributes nutrients, wastes, O 2, CO 2, hormones thermoregulation, osmoregulation, physiological homeostasis components heart, arteries, veins, capillaries blood Lymphatic system (cont d)

3 Major divisions of the circulatory system Lymphatic system functions immune response, lipid absorption, returns fluids from tissues to venous cardiovascular system components Lymph Capillaries, Vessels, Ducts Lymph Organs Lymph Nodes Thymus Spleen Tonsils Peyer s Patches Vermiform Appendix Lymph

4 Layers of the cardiovascular system listed from luminal to superficial: Vessels Heart Endothelium Tunica Intima Endocardium Muscle and CT Tunica Media Myocardium Covering Tunica Adventitia Pericardium General terms Collateral Circulation Anastomosis

5 Arteries by definition: conduct blood away from heart typically conduct O 2 -rich blood exceptions are pulmonary arteries and umbilical arteries narrow diameter (than veins) thicker wall (than veins) Tunica Intima maybe Stratified Squamous Epithelium Tunica Media alternating bands of Smooth Muscle and Elastic CT high pressure located deep (not merely subcutaneous) except to pass joints typically co-occur with veins and nerves of same name

6 Veins by definition: conduct blood towards the heart typically conduct O 2 -depleted blood exceptions are pulmonary veins and umbilical vein large diameter thin wall low pressure passive valves two tier system of both superficial (subcutaneous) and deep vessels Capillaries leaky vessels consist only of Tunica Intima only

7 Blood Plasma extracellular matrix water, dissolved salts, proteins, nutrients, urea, hormones, CO 2 Albumin osmolarity Fibrinogen clotting Globulins immune response Formed elements of blood cellular Hematopoiesis from pleuripotent stem or progenitor cells Red Bone Marrow in adults Yolk Sac, Spleen, Liver, Kidneys in embryo and fetus

8 Erythrocytes or Red Blood Cells (RBC s) carry hemoglobin, four-ringed protein that binds iron (hence O 2 ) most numerous blood cell type biconcave anucleate 7.5 µm in diameter Rollo formation ~120 day lifespan unlike leucocytes, RBC s do not escape capillaries

9 Leucocytes or White Blood Cells (WBC s) Granulocytes or Polymorphonuclear Cells extracellular digestion by release of lytic enzymes innate immune response types distinguished by hemotoxylin and eosin (H&E) staining Neutrophils neutral ph, red and blue most numerous granulocyte, major constituent of pus Eosinophils acid, red Basophils and Mast Cells basic, blue produce edema, release heparin and histamine Agranulocytes Monocytes or Macrophages (mature) amoeboid cells, internal digestion by phagocytosis Lymphocytes many types: t-lymphocytes, b-lymphocytes, natural killer-lymphocytes recognize, target, and kill antigens adaptive immune response Thrombocytes or blood platelets small pieces of cells involved in clotting

10 Heart Pericardial cavity middle mediastinum Parietal Pericardium Serous Pericardium Fibrous Pericardium Heart suspended by great vessels superiorly (anterior and posterior) tissue layers of heart Visceral pericardium (or simply pericardium ) serosa Myocardium cardiac striated muscle Endocardium simple squamous epithelium margins of the heart superior sternal angle to 4 th thoracic intervertebral disc right ½ inch parasternal apex left midclavicular line or ½ inch medial to areola in males inferior xiphisternal joint to 8 th thoracic intervertebral disc

11 Pulmonary circulation to and from lungs Systemic circulation to and from body Intrinsic circulation of the heart Hepatic Portal circulation separated as right and left chambers of the heart 2 Atria (s. atrium) 2 Ventricles Interatrial Septum Interventricular Septum Atrioventricular Septum

12 Systemic circulation Superior vena cava from upper ½ body Inferior vena cava from lower ½ body Coronary sinus intrinsic circulation of heart Right atrium Right ventricle Pulmonary circuit Pulmonary trunk to pulmonary arteries Lungs Pulmonary veins Left atrium Left ventricle Systemic circulation Ascending Aorta to everything

13 General features of Atria smaller and thinner walled than ventricles Musculi Pectinati Auricles Atria separated from one another by Interatrial Septum Atria separated from ventricles by Atrioventricular Septum contains Atrioventricular (AV) Node beginning of Moderator Band

14 Right Atrium Sinus Venosus posterior right, smooth surface receives Superior and Inferior Venae Cavae and Coronary Sinus Crista Terminalis Sinoatrial (SA) Node the pacemaker Fossa Ovalis vestige of Foramen Ovale (fetal interatrial bypass) Left Atrium receives Upper and Lower Right and Upper and Lower Left Pulmonary Veins

15 General Features of Ventricles larger and thicker walled than atria Trabeculae Carnae Atrioventricular (AV) Valves active, muscular Cusps Chordae Tendineae Papillary muscles Semilunar Valves passive Ventricles separated from one another by interventricular septum contains Moderator Band or Purkinje Fibers

16 Right Ventricle Right AV or Tricuspid Valve three cusps opening of Pulmonary Trunk anterior superior left Pulmonary Semilunar Valve Left Ventricle Left AV or Bicuspid or Mitral Valve two cusps opening of Ascending Aorta anterior superior right Aortic Semilunar Valve

17 Electrical conduction of the heart Sinoatrial Node pacemaker Atrioventricular Node Moderator Band or Bundle of HIS or Purkinje Fibers

18 Locations to listen to heart valves Aortic Semilunar Right 2 nd intercostal space parasternal Pulmonary Semilunar Left 2 nd intercostal space parasternal Tricuspid Right 5 th intercostal space parasternal Bicuspid or Mitral Left 5 th intercostal space midclavicular

19 Fetal circulation fetal structure R&L Umbilical Arteries Umbilical Vein Ductus Venosus (also Portal Sinus Foramen Ovale Ductus Arteriosus fate Vesical Arteries and Median Umbilical Ligament Ligamentum Teres in Falciform Ligament Ligamentum Venosus Hepatic Portal Vein) Fossa Ovalis Ligamentum Arteriosum

20 Fetal Definitive

21 Branches of the Thoracic Aorta listed in order of branching 1) Ascending Aorta branches: Right and Left Coronary Arteries 2) Aortic Arch branches: a) Brachiocephalic Artery branches: i) Right Common Carotid ii) Right Subclavian Artery b) Left Common Carotid Artery c) Left Subclavian Artery 3) Descending Aorta branches: segmental Esophageal and Intercostal arteries

22 Superior Vena Cava venous counterpart to the Thoracic Aorta drains entire upper half of body located to right side of Aortic Arch, on mediastinal surface of right lung begins with the union of Right and Left Brachiocephalic Veins terminates in Sinus Venosus of Right Atrium Tributaries 1) Left Brachiocephalic or Left Innominate Vein long, horizontal, anterior to branches of aortic arch begins with union of L Subclavian and L Internal Jugular Veins 2) Right Brachiocephalic or Right Innominate Vein short, vertical begins with union of R Subclavian and R Internal Jugular Veins 3) Azygos Vein drains right Intercostal Veins drains left Intercostal Veins via Hemiazygos Veins

23 Branches of the Abdominal Aorta listed in order of branching 1) Coeliac Trunk to superior abdominal organs 2) Superior Mesenteric Artery to Jejunum, Ileum, Large Intestine up to and including Transverse Colon 3) Right and Left Renal Arteries 4) Right and Left Gonadal (Testicular or Ovarian) Arteries 5) Inferior Mesenteric Artery to Descending and Sigmoid Colons and superior Rectum 6) Right and Left Common Iliac Arteries to pelvic region and lower limbs

24 Inferior Vena Cava venous counterpart to the Abdominal Aorta drains entire lower half of body its main tributaries are those corresponding only to paired arterial branches of the Abdominal Aorta, except the Hepatic vein located to right side of Abdominal Aorta, anterior to lumbar vertebrae begins with the union of the Right and Left Common Iliac veins terminates in Sinus Venosus of Right Atrium

25 Tributaries of the Inferior Vena Cava listed in order of union 1) Right and Left Common Iliac Veins 2) Right Gonadal (Testicular or Ovarian) Vein 3) Right and Left Renal Veins Left Renal Vein - long, crosses anterior to Abdominal Aorta tributary of Left Renal Vein: Left Gonadal (Testicular or Ovarian) Vein 4) Hepatic Vein

26 Arterial Branches

27 Intrinsic circulation of the heart Coronary Arteries vs Cardiac Veins Branches of Right Coronary Artery Marginal (coronary) Artery on right margin of heart Circumflex (Coronary) Artery (right side) at Atrioventricular Septum

28 Branches of Left Coronary Artery Anterior Interventricular or Descending Artery at anterior interventricular septum anastomoses with Posterior Interventricular Artery Circumflex (Coronary) Artery (left side) branch: Posterior Interventricular or Descending Artery at posterior interventricular septum anastomoses with Anterior Interventricular Artery

29 Cardiac veins Small Cardiac Vein corresponds to Marginal Artery on right margin of heart Great Cardiac Vein corresponds to Anterior Interventricular Artery at anterior interventricular septum Middle Cardiac Vein corresponds to Posterior Interventricular Artery at Posterior Interventricular Septum Coronary Sinus alongside Circumflex Artery at Atrioventricular Septum receives Cardiac Veins and drains into Sinus Venosus of Right Atrium

30 All subsequent descriptions are for paired right and left vessels even though this is not specified in each case

31 Branches of the Common Carotid Arteries and their branches ends in two terminal branches at level of laryngeal eminence in carotid triangle 1) Internal Carotid Artery major branches of the Internal Carotid Artery: a) Middle Cerebral Artery to majority of Cerebrum via Carotid Canal passes through the Cavernous Sinus (a venous dural sinus surrounding the sella turcica) b) Ophthalmic Artery to orbit via optic canal select branches of Ophthalmic Artery: i) Central Artery enters eye within optic nerve branches of the Central Artery: Superior and Inferior Temporal Arteries to retina Superior and Inferior Nasal Arteries to retina ii) Supraorbital Artery 2) External Carotid Artery (continued)

32 Branches of the External Carotid Artery and its branches 1) Lingual Artery to tongue 2) Facial Artery crosses face from mandibular ramus to medial orbit 3) Superficial Temporal Artery to temporal fossa, scalp 4) Occipital Artery 5) Maxillary Artery to muscles of mastication, palate, teeth, and infraorbital region select branches of maxillary artery: a) Sphenopalatine Artery to nasal cavity and palate b) Middle Meningeal Artery to cranial cavity via foramen spinosum c) Alveolar Arteries (3) to teeth d) Infraorbital Artery to middle face

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34 Branches of the Subclavian Arteries and their branches 1) Vertebral Artery to cranial cavity via foramen magnum 2) Thyrocervical Trunk to scapular and cervical regions 3) Internal Thoracic Artery 4) Costocervical Trunk 5) Dorsal Scapular Artery 6) Axillary Artery (terminal branch, simply a change of name) Subclavian Artery Axillary Artery at first rib to anterior and lateral thoracic regions branches: a) Thoracoacromial Artery (travels with Lateral Pectoral nerve) b) Subscapular Artery c) Lateral Thoracic artery (travels with Long Thoracic nerve) d) Circumflex Humeral Artery e) Brachial Artery (terminal branch) Axillary Artery Brachial Artery at Teres Major muscle (continued)

35 Location of the Brachial Artery Proximally: on medial side of brachium between anterior and posterior compartments but within anterior compartment Distally: medial to tendon of biceps brachii in antecubital region Major Branches of the Brachial Artery 1) Profunda Brachii Artery serves posterior compartment 2) Superior and Inferior Ulnar Collateral Arteries 3) Radial Artery (one terminal branch of brachial artery) terminates in manus as: Deep Palmar Arch anastomoses with Ulnar Artery 4) Ulnar Artery (another terminal branch of brachial artery) branches: Common Interosseous Artery and its branches: Anterior Interosseous Artery Posterior Interosseous Artery terminates in manus as: Superficial Palmar Arch anastomoses with Radial Artery

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37 Circulation of the cranial cavity 1) Internal Carotid Artery Middle Cerebral Artery (at carotid canal) serves frontal, parietal, and temporal lobes of the cerebrum passes through Cavernous Sinus (a venous plexus of the dural sinuses) four levels from deep to superficial emerges through Central Sulcus or Fissure between frontal and parietal lobes of cerebrum emerges through Sylvian or Lateral Sulcus or Fissure between frontal and temporal lobes of cerebrum branches: Anterior Cerebral Artery - to anterior inferior frontal lobe Right and Left Anterior Cerebral Arteries anastomose via: Anterior Communicating Artery Posterior Communicating Artery an anastomosis with posterior cerebral artery (continued)

38 Circulation of the cranial cavity 2) Right and Left Vertebral arteries anastomose to form: Basilar artery (unpaired) branches: Cerebellar arteries Posterior cerebral artery terminal paired branches anastomoses with middle cerebral artery via posterior communicating artery 3) Middle meningeal Artery to meninges and calvarium

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40 Branches of the coeliac trunk and their unpaired major branches 1) Left Gastric Artery branches to lesser curvature of stomach and esophagus 2) Common Hepatic Artery branches: a) Hepatic Artery b) Gastroduodenal Artery branches to (right side of) greater curvature of stomach, duodenum, and head and neck of pancreas 3) Splenic Artery branches to fundus and (left side of) greater curvature of stomach, and body and tail of pancreas

41 Branches of Common Iliac arteries and their major branches 1) Internal iliac Artery branches: a) Iliolumbar Artery (serves iliopsoas muscle) b) Lateral Sacral Artery c) Superior and Inferior Gluteal Arteries d) Umbilical Artery of fetus or Superior Vesical Artery of adult e) Uterine and Vaginal Arteries of female or Inferior Vesical Artery of male f) Middle Rectal ( Middle Hemorrhoidal ) Artery g) Obturator artery to obturator muscles h) Internal Pudendal Artery - to perineum Branch (one among many): Inferior Rectal ( Inferior Hemorrhoidal ) Artery 2) External Iliac artery (continued)

42 Branches of Internal Iliac artery

43 Branches of Internal Iliac artery

44 Branches of External Iliac Artery and its branches 1) Inferior Epigastric artery 2) Circumflex Iliac artery 3) Femoral Artery (terminal branch a simple change of name) External Iliac Artery femoral artery at inguinal ligament Branches of Femoral Artery: a) External Pudendal arteries to external genitalia, i.e., scrotum in males or labia majora in females b) Profunda Femoris Artery to muscles of medial and posterior compartments its branches: Medial and Lateral Circumflex Femoral Arteries and their branches descend medial and lateral thigh c) Popliteal Artery (terminal branch, a simple change of name) Femoral Artery Popliteal Artery at adductor hiatus (continued)

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46 Branches of Popliteal Artery and their major branches 1) Genicular arteries (superior medial and lateral, inferior medial and lateral) 2) Sural Arteries 3) Anterior Tibial Artery (terminal branch of Popliteal Artery) branch (terminal): Dorsalis Pedis Artery 4) Posterior Tibial Artery (terminal branch of Popliteal Artery) branches: a) Peroneal Artery b) Medial and Lateral Plantar Arteries (terminal branches of Posterior Tibial Artery)

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48 Pulse Superficial Temporal Artery temporal fossa Carotid Artery (Common or External) anterior to sternocleidomastoid at level of laryngeal eminence Brachial Artery antecubital fossa medial to tendon of biceps brachii Radial Artery anterior distal radius Femoral Artery femoral triangle Popliteal Artery popliteal fossa Posterior Tibial Artery posterior to medial malleolus Dorsalis Pedis Artery between tendons of extensor hallucis longus and extensor digitorum longus

49 Venous drainage of the Head and Neck for most arteries there are corresponding veins of the same name except: Internal, External, and Common Carotid arteries veins with no corresponding arteries: 1) Internal Jugular Vein drains cranial cavity, anterior face, tongue and pharynx Sigmoid Dural Sinus Internal Jugular Vein at jugular foramen major tributaries: a) Facial Vein b) Lingual Vein 2) External Jugular Vein drains lateral and posterior scalp, posterior face, infratemporal fossa major tributaries: a) Maxillary Vein b) Superficial Temporal Vein 3) Anterior Jugular Vein drains superficial thyroid region

50 Brain Ventricles, Cerebrospinal Fluid, Meninges, Dural Sinuses Choroid Plexus a capillary-like structure within some ventricles Cerebrospinal Fluid (CSF) blood filtrate produced by choroid plexus that bathes the central nervous system from within and without Structures filled with CSF: 1) Subarachnoid Space 2) Brain Ventricles - derivatives of the embryological neural tube (CNS) a) Lateral Ventricles in paired cerebral hemispheres of forebrain b) Third Ventricle between right and left thalami and within hypothalamus of forebrain c) Cerebral Aqueduct narrow tube in midbrain uniting third and fourth ventricles d) Fourth Ventricle between cerebellum and pons of hindbrain e) Central Canal of the spinal cord

51 Meninges 1) Pia Mater 2) Arachnoid Mater Subarchnoid Space location of CSF between pia and arachnoid maters Arachnoid Villi drain CSF from subarachnoid space to dural sinuses 3) Dura Mater continuous with periosteum of calvarium and vertebral canal extensions of dura extending into fissures of brain: a) Falx Cerebri midsagittal septum between cerebral hemispheres b) Falx Cerebelli midsagittal septum between cerebellar hemispheres c) Tentorium Cerebelli horizontal septum between occipital lobes of cerebrum and cerebellum

52 Dural Sinuses 1) Superior Sagittal Sinus superior margin of falx cerebri inferior to sagittal suture 2) Inferior Sagittal Sinus along inferior margin of falx cerebri 3) Straight Sinus along union of falx cerebri and tentorium cerebelli 4) Transverse Sinuses along lateral margin of tentorium cerebelli Superior Sagittal Sinus Right Transverse Sinus at internal occipital protuberance Straight Sinus Left Transverse Sinus at internal occipital protuberance 5) Sigmoid Sinuses continuation of Transverse Sinuses sigmoid sinus Internal Jugular Vein at jugular foramen (continued)

53 Dural Sinuses (continued) 6) Cavernous Sinus venous plexus surrounding Sella Turcica passed through by Internal Carotid Artery, niii, niv, nv 1, nv 2, nvi receives Ophthalmic Vein* drains indirectly to Transverse and Sigmoid sinuses * Facial Vein anastomoses with Ophthalmic Vein, unlike arteries of same names this is a superficial venous pathway into the cranial cavity and potential source of infection

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55 Hepatic Portal Vein terminates in liver tributaries: 1) Splenic Vein 2) Superior Mesenteric Vein 3) Inferior Mesenteric Vein

56 Venous drainage of the upper extremity and girdle for every artery there are corresponding veins of the same name Superficial veins with no corresponding arteries: 1) Cephalic Vein drains dorsum of hand, lateral antebrachium and brachium ends in Axillary Vein at Deltopectoral Triangle 2) Basilic Vein Anterior medial antebrachium and medial brachium ends in Brachial Vein 3) Median Cubital Vein Antecubital anastomosis of Cephalic and Basilic Veins

57 Venous drainage of the lower extremity and pelvic region for every artery there are corresponding veins of the same name Superficial veins with no corresponding arteries: Great or Long Saphenous Vein drains medial crus and thigh ends in Femoral Vein in femoral triangle Short Saphenous Vein drains sural region ends in Popliteal Vein in popliteal region

58 Lymphatic system Functions Immune response lipid absorption removes dead blood cells from circulation, produces bilirubin returns fluids and mobile leucocytes from extracellular tissues to venous cardiovascular system

59 Terminal lymph vessels 1) Right Lymphatic duct drains upper right ¼ of body terminates in right subclavian vein 2) Thoracic duct drains all but upper right ¼ of body terminates in left subclavian vein Cysterna Chyli bulb-like expansion of inferior end of thoracic duct

60 Lymph Nodes scattered and concentrated in locations throughout body, especially major joints, the cervical region, and digestive organs Leucocytes within nodes attack antigens and impede them from circulating Afferent and Efferent lymph vessels - lead to and from nodes parts of the node: Capsule Trabeculae Nodules Germinal Centers site of maturation and acquisition of new antibodies by b-lymphocytes and their clonal proliferation Reticular fibers Macrophages and Lymphocytes

61 Distribution of Select Major Groups of Lymph Nodes of head: Parotid Submaxillary or Submandibular Occipital of neck: Cervical superior and inferior deep surround internal jugular veins Superficial superior anterior triangle (continued)

62 Distribution of Select Major Groups of Lymph Nodes of upper limb and girdle: Axillary Pectoral, Subclavicular, Subscapular, Brachial of lower limb and girdle (including genitals and perineum): Inguinal femoral triangle of thoracic cavity: Tracheobronchial, Intercostal Mediastinal mostly concentrated around arteries of abdominal Cavity: Lumbar efferents to cisterna chyli many groups, mostly concentrated around and named after all arteries and their branches, as well as viscera of pelvic cavity (e.g., rectum)

63 Thymus site of maturation of t-lymphocytes primarily in youth located posterior to manubrium in superior mediastinum size at age 2 (maximal): from laryngeal eminence to mid-sternal body size at adolescence (replaced by adipose): jugular notch to sternal angle

64 Spleen blood filter removes dead erythrocytes from circulation populated by monocytes and macrophages degrades hemoglobin to bilirubin (subsequently excreted by liver) located in left hypochondriac region, to left of stomach Capsule Cords of Billroth reticular fibers