Seeley's Essentials of Anatomy and Physiology PDF

 2 Chapter 13 Blood Vessels and Circulation Lecture Outline © 2019 McGraw-Hill Education ...

 2 Chapter 13 Blood Vessels and Circulation Lecture Outline © 2019 McGraw-Hill Education  3 OBJECTIVES AT THE END OF THE SESSION THE STUDENT WILL BE ABLE TO: A. Identify anatomic and physiologic deviations of the circulatory system. B. Verbalize appreciation of the clinical significance of Blood Vessels and Circulation of Blood. C. Describe the structure and function of arteries, capillaries and veins. © 2019 McGraw-Hill Education  4 Blood Vessels Blood vessels outside the heart are divided into two classes: 1. The pulmonary vessels, which transport blood from the right ventricle of the heart through the lungs and back to the left atrium 2. The systemic vessels, which transport blood from the left ventricle of the heart through all parts of the body and back to the right atrium © 2019 McGraw-Hill Education  5 Blood Vessel Functions 1. Carry blood 2. Exchange nutrients, waste products, gases within tissues 3. Transport substances 4. Regulate blood pressure 5. Direct blood flow to tissues © 2019 McGraw-Hill Education  6 Vessel Structures Arteries: carry blood away from heart thick with a lot of elastic Veins: carry blood toward heart think with less elastic Capillaries: exchange occurs between blood and tissue fluids © 2019 McGraw-Hill Education  7 Venule Arteriole Capillaries Vein Artery © 2019 McGraw-Hill Education  8 Blood Flow Blood flows from arteries into arterioles Arterioles into capillaries Capillaries into venules Venules to small veins Veins return to heart © 2019 McGraw-Hill Education  9 Blood Vessel Walls Tunica intima: innermost layer simple squamous Tunica media: middle layer smooth muscle with elastic and collagen Tunica adventitia: outermost layer connective tissue © 2019 McGraw-Hill Education  10 Artery and Vein Figure 13.2 © 2019 McGraw-Hill Education ©Ed Reschke/Photolibrary/Getty Images  11 Types of Arteries Elastic arteries: largest in diameter thickest walls Example - aorta and pulmonary trunk Muscular arteries: medium to small size thick in diameter contain smooth muscle cells can control blood flow to body regions © 2019 McGraw-Hill Education  12 Arteries Figure 13.1a,b © 2019 McGraw-Hill Education  13 Capillaries Blood flows from arterioles into capillaries Capillaries branch to form networks Blood flow is regulated by smooth muscle cells, precapillary sphincters © 2019 McGraw-Hill Education  14 Capillary Network Figure 13.3 © 2019 McGraw-Hill Education  15 Capillary Structure Figure 13.1d © 2019 McGraw-Hill Education  16 Types of Veins Blood flows from capillaries into venules Blood flows from venules into small veins All 3 tunics are present in small veins Medium sized veins: collect blood from small veins and deliver to large veins Large veins: contain valves © 2019 McGraw-Hill Education  17 Blood Vessel Structure Figure 13.1 © 2019 McGraw-Hill Education  18 Valves Figure 13.4 © 2019 McGraw-Hill Education  19 Pulmonary Circulation Vessels Pulmonary circulation: blood vessels that carry blood from right ventricle to lungs and back from left atrium of heart Pulmonary trunk: blood pump from right ventricle towards lung Pulmonary veins: exit lungs and carry O2 rich blood to left atrium © 2019 McGraw-Hill Education  20 Systemic Circulation Vessels The systemic circulation carries blood from the left ventricle to the tissues of the body and back to the right atrium. Oxygenated blood from the pulmonary veins passes from the left atrium into the left ventricle and from the left ventricle into the aorta. Arteries distribute blood from the aorta to all portions of the body © 2019 McGraw-Hill Education  21 Blood Flow through the Circulation Figure 13.5 © 2019 McGraw-Hill Education  22 © 2019 McGraw-Hill Education  23 Parts of the Aorta 1 Ascending: passes superiorly from left ventricle Aortic arch: 3 major arteries which carry blood to head and upper limbs Descending: extends through thorax and abdomen to pelvis © 2019 McGraw-Hill Education  24 Parts of the Aorta 2 Thoracic: part of descending aorta that extends through thorax to diaphragm Abdominal: descending aorta that extends from diaphragm where it divides at the common iliac arteries © 2019 McGraw-Hill Education  25 Major Arteries Figure 13.6 © 2019 McGraw-Hill Education  26 Branches of the Aorta Figure 13.7 © 2019 McGraw-Hill Education  27 Arteries of the Head and Neck 1 Branches of aortic arch: brachiocephalic artery left common carotid artery left subclavian Brachiocephalic artery: first branch off aortic arch supplies blood to right side of head and neck © 2019 McGraw-Hill Education  28 Arteries of the Head and Neck 2 Left common carotid artery: 2nd branch off aortic arch supplies blood to the left side of head and neck Left subclavian artery: 3rd branch off aortic arch supplies blood to left upper limbs © 2019 McGraw-Hill Education  29 Arteries of the Head and Neck 3 Right common carotid artery: branches off brachiocephalic artery supplies blood to right side of head and neck Right subclavian artery: branches off brachiocephalic artery supplies blood to right upper limbs © 2019 McGraw-Hill Education  30 Arteries of the Head and Neck Figure 13.8 © 2019 McGraw-Hill Education  31 © 2019 McGraw-Hill Education  32 Cerebral Arterial Circle Figure 13.10 © 2019 McGraw-Hill Education  33 Major Arteries of the Head and Thorax Figure 13.9 © 2019 McGraw-Hill Education  34 Arteries of the Upper Limbs 1 Axillary arteries: continuation of subclavian supply blood deep in clavicle Brachial arteries: continuation of axillary where blood pressure measurements are taken © 2019 McGraw-Hill Education  35 Arteries of the Upper Limbs 2 Ulnar arteries: branch of brachial artery near elbow Radial arteries: branch of brachial artery supply blood to forearm and hand pulse taken here © 2019 McGraw-Hill Education  36 Arteries of the Upper Limbs 3 Figure 13.11 © 2019 McGraw-Hill Education  37 Abdominal Aorta Branches 1 Celiac trunk arteries: supply blood to stomach, pancreas, spleen, liver, upper duodenum Superior mesenteric arteries: supply blood to small intestines and upper portion of colon Inferior mesenteric arteries: supply blood to colon © 2019 McGraw-Hill Education  38 Abdominal Aorta Branches 2 Renal arteries: supply blood to kidneys Hepatic arteries: supply blood to liver Testicular arteries: supply blood to testes Ovarian arteries: supply blood to ovaries © 2019 McGraw-Hill Education  39 Abdominal Aorta Branches 3 Inferior phrenic arteries: supply blood to diaphragm Lumbar arteries: supply blood to lumbar vertebra and back muscles © 2019 McGraw-Hill Education  40 Arteries of Pelvis Common iliac arteries: branches from abdominal aorta divides into internal iliac arteries External iliac arteries: division of common iliac artery supply blood to lower limbs Internal iliac arteries: division of common iliac supply blood to pelvic area © 2019 McGraw-Hill Education  41 © 2019 McGraw-Hill Education  Major Arteries of the Abdomen and 42 Pelvis Figure 13.12 © 2019 McGraw-Hill Education  43 Arteries of the Lower Limbs 1 Femoral arteries: supply to thigh Popliteal arteries: supply blood to knee Anterior and posterior arteries: supply blood to leg and foot Fibular arteries: supply blood to lateral leg and foot © 2019 McGraw-Hill Education  44 Arteries of the Lower Limbs 2 Figure 13.13 © 2019 McGraw-Hill Education  45 Veins 1 Veins return blood to the heart. In the systemic circulation, the blood returning to the heart is deoxygenated. In the pulmonary circulation, the blood returning to the heart in the pulmonary veins is oxygenated. © 2019 McGraw-Hill Education  46 Veins 2 Superior vena cava: returns blood from head, neck, thorax, and right upper limbs empties into right atrium of heart Inferior vena cava: returns blood from abdomen, pelvis, lower limbs empties into right atrium of heart © 2019 McGraw-Hill Education  47 Major Veins Figure 13.14 © 2019 McGraw-Hill Education  48 Veins of the Head and Neck 1 External jugular vein: drain blood from head and neck empties into subclavian veins Internal jugular vein: drain blood from brain, face, neck empty into subclavian veins © 2019 McGraw-Hill Education  49 Veins of the Head and Neck 2 Subclavian veins: forms brachiocephalic veins Brachiocephalic veins: join to form superior vena cava © 2019 McGraw-Hill Education  50 Veins of the Head and Neck 3 Figure 13.15 © 2019 McGraw-Hill Education  51 Veins of the Upper Limbs 1 Brachial veins: empty into axillary vein Cephalic veins: empty into axillary vein and basilic vein Median cubital veins: connects to cephalic vein near elbow © 2019 McGraw-Hill Education  52 Veins of the Upper Limbs 2 Figure 13.16 © 2019 McGraw-Hill Education  53 Veins of the Thorax 1 Right and left brachiocephalic veins: drain blood from thorax into superior vena cava Azygos veins: drain blood from thorax into superior vena cava Internal thoracic veins: empty into brachiocephalic veins © 2019 McGraw-Hill Education  54 Veins of the Thorax 2 Posterior intercostal veins: drain blood from posterior thoracic wall drains into azygos vein on right side Hemiazygos vein: receives blood from azygos vein of left side © 2019 McGraw-Hill Education  55 Veins of the Thorax 3 Figure 13.17 © 2019 McGraw-Hill Education  56 Veins of the Abdomen and Pelvis 1 Common iliac vein: formed from external and internal iliacs empty into inferior vena cava External iliac vein: drains blood from lower limbs empty into common iliac vein © 2019 McGraw-Hill Education  57 Veins of the Abdomen and Pelvis 2 Internal iliac vein: drains blood from pelvic region empties into common iliac vein Renal vein: drains blood from kidneys © 2019 McGraw-Hill Education  58 Major Veins of the Abdomen and Pelvis Figure 13.18 © 2019 McGraw-Hill Education  59 © 2019 McGraw-Hill Education  60 Hepatic Portal System Liver is a major processing center for substances absorbed by intestinal tract. Portal system: vascular system that begins with capillaries in viscera and ends with capillaries in liver uses splenic vein and superior mesenteric vein © 2019 McGraw-Hill Education  61 Veins of the Hepatic Portal System Figure 13.19 © 2019 McGraw-Hill Education  62 Veins of the Lower Limbs 1 Femoral veins: drain blood from thigh and empty into external iliac vein Great saphenous veins: drain from foot and empty into femoral vein Popliteal veins: drain blood from knee and empty into femoral vein © 2019 McGraw-Hill Education  63 Veins of the Lower Limbs 2 Figure 13.20 © 2019 McGraw-Hill Education  64 Blood Pressure Blood pressure is the measure of force blood exerts against blood vessel walls. Systolic pressure: contraction of heart Diastolic pressure: relaxation of heart Average Blood Pressure: 120/80 © 2019 McGraw-Hill Education  65 Measuring Blood Pressure Figure 13.21 © 2019 McGraw-Hill Education  66 Pulse Pressure Pulse pressure is the difference between systolic and diastolic blood pressures. Example - 120 for systolic / 80 for diastolic; pulse pressure is 40 mm Hg pulse pressure points can be felt near large arteries © 2019 McGraw-Hill Education  67 Body Locations to Evaluate Pulses Figure 13.23 © 2019 McGraw-Hill Education  68 Capillary Exchange 1 Most exchange across capillary wall’s occurs by diffusion Blood pressure, capillary permeability and osmosis affect movement of fluids across capillary walls. Net movement of fluid from blood into tissues Fluid gained in tissues is removed by lymphatic system © 2019 McGraw-Hill Education  69 © 2019 McGraw-Hill Education  70 Capillary Exchange 2 Figure 13.24 © 2019 McGraw-Hill Education  71 Local Control of Blood Flow Local control achieved by relaxation and contraction of precapillary sphincters Sphincters relax blood flow increases Precapillary sphincters controlled by metabolic needs of tissues Concentration of nutrients also control blood flow Blood flow increases when oxygen levels decrease © 2019 McGraw-Hill Education  Local Control of Blood Flow through 72 Capillary Beds Figure 13.25 © 2019 McGraw-Hill Education  73 Nervous Control of Blood Flow Vasomotor center: sympathetic division controls blood vessel diameter Vasomotor tone: state of partial constriction of blood vessels increase causes blood vessels to constrict and blood pressure to go up © 2019 McGraw-Hill Education  74 Hormonal Control of Blood Flow The sympathetic division also regulates hormonal control of blood flow through the release of epinephrine and norepinephrine from the adrenal medulla. In most blood vessels, these hormones cause constriction, which reduces blood flow. In some tissues, such as skeletal muscle and cardiac muscle, these hormones cause the blood vessels to dilate, increasing blood flow. © 2019 McGraw-Hill Education  75 Nervous Regulation of Blood Vessels Figure 13.26 © 2019 McGraw-Hill Education  76 Mean Arterial Pressure 1 An adequate blood pressure is required to maintain blood flow through the blood vessels of the body. Several regulatory mechanisms ensure that blood pressure remains adequate for this task. Mean arterial pressure (MAP) is a calculated value that reflects an average arterial pressure in various vessels of the body. © 2019 McGraw-Hill Education  77 Mean Arterial Pressure 2 The body’s MAP is equal to the cardiac output (CO) times the peripheral resistance (PR). Cardiac output is equal to the heart rate (HR) times the stroke volume (SV). Peripheral resistance is the resistance to blood flow in all the blood vessels. MAP = CO × PR © 2019 McGraw-Hill Education  78 Mean Arterial Pressure 3 The MAP changes in response to changes in HR, SV, or PR. The mean arterial pressure changes over our lifetime. MAP is about 70 mm Hg at birth. It is maintained at about 95 mm Hg from adolescence to middle age, and may reach 110 mm Hg in a healthy older person. © 2019 McGraw-Hill Education  79 Baroreceptor Reflexes Baroreceptor reflexes activate responses to blood pressure in normal range Baroreceptors respond to stretch in arteries due to increased pressure Located in carotid sinuses and aortic arch Change peripheral resistance, heart rate, stroke volume in response to blood pressure © 2019 McGraw-Hill Education  80 Baroreceptor Reflex Mechanisms Figure 13.27 © 2019 McGraw-Hill Education  81 Baroreceptor Effects on Blood Pressure Figure 13.28 © 2019 McGraw-Hill Education  82 Chemoreceptor Reflex Chemoreceptors are sensitive to changes in blood oxygen, carbon dioxide, and pH Chemoreceptors are located in carotid bodies and aortic bodies which lie near carotid sinuses and aortic arch They send action potentials along sensory nerve to medulla oblongata © 2019 McGraw-Hill Education  83 Chemoreceptor Reflex Mechanisms Figure 13.29 © 2019 McGraw-Hill Education  84 Adrenal Medullary Mechanism 1 1. Stimuli increase sympathetic stimulation to adrenal medulla 2. Adrenal medulla secretes epinephrine and norepinephrine into blood 3. This causes increased heart rate and stroke volume and vasoconstriction 4. Vasodilation of blood vessels in skeletal and cardiac muscle © 2019 McGraw-Hill Education  85 Adrenal Medullary Mechanism 2 Figure 13.30 © 2019 McGraw-Hill Education  Renin-Angiotensin-Aldosterone 86 Mechanism 1 1. Reduce blood flow causes kidneys to release renin 2. Renin acts on angiotensinogen to produce angiotensin I 3. Angiotensin-converting enzyme converts angiotensin I to angiotensin II 4. Angiotensin II causes vasoconstriction 5. Angiotensin II acts on adrenal cortex to release aldosterone © 2019 McGraw-Hill Education  Renin-Angiotensin-Aldosterone 87 Mechanism 2 6. Aldosterone acts on kidneys causes them to conserve sodium and water 7. Result less water lost in urine and blood pressure maintained © 2019 McGraw-Hill Education  Renin-Angiotensin-Aldosterone 88 Mechanism 3 Figure 13.31 © 2019 McGraw-Hill Education  89 Antidiuretic Hormone Mechanism 1 1. Nerve cells in hypothalamus release antidiuretic hormone (ADH) when concentration of solutes in plasma increases or blood pressure decrease 2. ADH acts of kidneys and they absorb more water (decrease urine volume) 3. Result is maintain blood volume and blood pressure © 2019 McGraw-Hill Education  90 Antidiuretic Hormone Mechanism 2 Figure 13.32 © 2019 McGraw-Hill Education  91 Long-Term Control of Blood Pressure Figure 13.33 © 2019 McGraw-Hill Education  92 Aging and Blood Vessels Arteriosclerosis: makes arteries less elastic Atherosclerosis: type of arteriosclerosis from deposit of materials in artery walls (plaque) Factors that contribute to atherosclerosis: lack of exercise, smoking, obesity, diet high in cholesterol and trans fats, some genetics © 2019 McGraw-Hill Education  93 Atherosclerotic Plaque Figure 13.34 © 2019 McGraw-Hill Education  94 References: VanPutte, C. L. , Regan, J., & Russo, A. (2019). Seeley’s Essentials of Anatomy and Physiology (11th ed.). U. K.: McGraw-Hill Education. Patton, K. et al. (2012). Essentials of Anatomy and Physiology. Missouri, U.S.A. : Elsevier, Inc. Marieb, E. (2009). Essentials of human anatomy (9th ed.). San Francisco: Benjamin Cummings Publishing Inc © 2019 McGraw-Hill Education  95 © 2019 McGraw-Hill Education