2 Objectives 28-1 Spell, define, and correctly use the Key Terms in this chapter. 28-2Describe the structure of the heart and the function of each part. 28-3Trace the flow of blood through the heart. 29-4List the most common heart sounds and what events produce them. 28-5Explain how heart rate is controlled. The Circulatory System
3 Objectives (cont.) 28-6List the different types of blood vessels and describe the functions of each. 28-7Define blood pressure and tell how it is controlled. 28-8Trace the flow of blood through the pulmonary and systemic circulation. 28-9List the major arteries and veins of the body and describe their locations List and describe the components of blood. The Circulatory System
Give the functions of red blood cells, the different types of white blood cells, and platelets List the substances normally found in plasma Explain how bleeding is controlled Explain the differences among type A blood, type B blood, type AB blood and type O blood Explain the difference between Rh positive blood and Rh negative blood. Objectives (cont.) The Circulatory System
Explain the importance of blood typing and tell which blood types are compatible List the organs of the lymphatic system and give their locations and functions Define lymph and tell how it is circulated in the body Describe signs, symptoms, causes, and treatments of various diseases and disorders of the heart, blood vessels, blood and the lymphatic system. Objectives (cont.) The Circulatory System
6 Introduction Circulation is the process of sending blood: To the lungs to pick up oxygen To the digestive system to pick up nutrients For delivery of oxygen and nutrients to all organ systems of the body The circulatory system consists of the heart and blood vessels. This system also circulates waste products to certain organ systems so these wastes can be removed from the blood. The lymphatic system is included because it also circulates fluids throughout the body.
7 Structure of the Heart A cone-shaped organ about the size of a loose fist Within the mediastinum and extends from the level of the second rib to about the level of the sixth rib Slightly left of the midline of the body. Heart is bordered: laterally by the lungs posteriorly by the vertebral column anteriorly by the sternum Inferiorly the heart rests on the diaphragm.
8 Coverings and Walls of the Heart Heart Coverings Pericardium - covers the heart and large blood vessels Visceral pericardium - innermost layer Parietal pericardium - lays on top of the visceral pericardium Heart Walls: Epicardium - the outermost layer Myocardium - the middle layer Endocardium - the innermost layer Click for Larger View
9 Coverings and Walls of the Heart
10 Heart Chambers Heart contains four hollow chambers Two atria – left and right Two ventricles – left and right Click for Larger View
11 The Heart Labeled
12 The Heart – No Labels Identify the Parts of the Heart A. L. M. O. P. S. R. Q. N. C. G. H. I. J. K. E. D. F. B. Click Next for Answers
13 The Heart – Answers A.Aortic arch B.Right pulmonary artery C.Superior vena cava D.Ascending aorta E.Right pulmonary veins F.Pulmonary semilunar valve G.Right Atrium H.Right ventricle I.Tricuspid valve J. Inferior vena cava K. Descending aorta L. Left pulmonary artery M. Pulmonary trunk N. Left pulmonary veins O. Left atrium P. Aortic semilunar valve Q. Mitral (bicuspid) valve R. Septum S. Left ventricle
14 Heart Valves Tricuspid valve Tricuspid valve - prevents blood from flowing back into the right atrium when the right ventricle contracts Bicuspid valve Bicuspid valve - prevents blood from flowing back into the left atrium when the left ventricle contracts Pulmonary valve Pulmonary valve - prevents blood from flowing back into the right ventricle Aortic valve Aortic valve - prevents blood from flowing back into the left ventricle
15 Path of Blood Through the Heart Deoxygenated blood in from body Deoxygenated blood in Oxygenated blood in lungs Atria ContractVentricles Contract Deoxygenated blood out to lungs Oxygenated blood out to body
16 Heart Sounds One cardiac cycle - One cardiac cycle - you can hear two heart sounds (lubb and dupp) when valves in the heart snap shut Lubb – 1 st sound Lubb – 1 st sound - when the ventricles contract and the tricuspid and bicuspid valves snap shut Dupp – 2 nd sound Dupp – 2 nd sound - when the atria contract and the pulmonary and aortic valves snap shut.
17 Apply Your Knowledge Your 8-year-old patient has asked you why his heart makes two noises. What would you tell him?
18 Answer Apply Your Knowledge - Answer Lubb – 1 st sound Lubb – 1 st sound - when the ventricles contract and the tricuspid and bicuspid valves snap shut Dupp – 2 nd sound Dupp – 2 nd sound - when the atria contract and the pulmonary and aortic valves snap shut Your 8-year-old patient has asked you why his heart makes two noises. What would you tell him?
19 Heart Rate Cardiac conduction system consists of a group of structures that send electrical impulses through the heart. When cardiac muscle receives an electrical impulse, it will contract.
20 Blood Vessels Arteries and Arterioles Arteries and Arterioles strongest of the blood vessels carry blood away from the heart easily and are under high pressure have thick walls Veins and Venules Veins and Venules no pressure in veins - does not move very easily valves in veins prevent blood from flowing backwards
21 Blood Vessels - Capillaries Branches of arterioles Branches of arterioles - the smallest type of blood vessel Connect arterioles to venules Connect arterioles to venules - only about one cell layer thick Oxygen and nutrients Oxygen and nutrients can pass out of a capillary into a body cell Carbon dioxide Carbon dioxide and other waste products can pass out of a body cell into a capillary
22 Blood Pressure Force blood exerts on the inner walls of blood vessels - highest in arteries and lowest in veins Systolic pressure - ventricles contract, blood pressure is greatest in the arteries Diastolic pressure -the ventricles relax, blood pressure in arteries is at its lowest Reported as the systolic number over the diastolic number.
23 Control of Blood Pressure Blood pressure is controlled to a large extent by the amount of blood pumped out of the heart Starling's law of the heart - blood enters the left ventricle, the wall of the ventricle is stretched. The more the wall is stretched, the harder it will contract, and the more blood it will pump out. Baroreceptors also help regulate blood pressure Low BP causes the cardiac center of the brain to increase heart rate
25 Major Blood Vessels Arterial System carry oxygen rich blood away from the heart pulmonary arteries carry oxygen poor blood paired - left and right artery of the same name
26 Major Blood Vessels (cont.) Venous System Venous System Vessels that carry blood toward the heart Pulmonary veins – carry oxygen rich blood Large veins often have the same names as the arteries they run next to Hepatic portal system Hepatic portal system collection of veins carrying blood to the liver Click for Larger View
27 Major Blood Vessels (cont.)
28 Apply Your Knowledge Your patient wants to know what the bottom number of his blood pressure means. What would you say?
29 Answer Apply Your Knowledge - Answer Diastolic pressure is when the ventricles of the heart relax, blood pressure in arteries is at its lowest. Your patient wants to know what the bottom number of his blood pressure means. What would you say?
30 Components of Blood A type of connective tissue Red blood cells (erythrocytes) White blood cells (leukocytes Platelets-contains cell fragments Plasma - fluid part of blood (55% of blood) Average-sized adult contains - 5 liters of blood Hematocrit (45%) - percentage of blood cells in a sample of blood Average-sized adult contains - 5 liters of blood Hematocrit (45%) - percentage of blood cells in a sample of blood
31 Red Blood Cells Transport oxygen throughout the body Are biconcave-shaped cells that are small enough to pass through capillaries Hemoglobin is a pigment found on RBCs Oxyhemoglobin carries oxygen and is bright red in color Deoxyhemoglobin does not carry oxygen and is a darker red color
32 Red Blood Cells (cont.)
33 White Blood Cells Granulocytes Neutrophils – (55%) destroying bacteria, viruses, and toxins in the blood stream Eosinophils – (3%) getting rid of parasitic infections such as worm infections Basophils –(1%) control inflammation and allergic reactionsAgranulocytes Monocytes – (8%) destroying bacteria, viruses, and toxins in blood Lymphocytes – (33%) immunity for the body
34 Blood Platelets Fragments of cells that are found in the blood stream Thrombocytes are important in the clotting of blood 130,000 to 360,000 platelets per cubic millimeter of blood
35 Controlling Bleeding Hemostasis - the stoppage of bleeding Three processes of hemostasis Blood vessel spasm Platelet plug formation Blood coagulation
36 Platelet Plug Formation
37 Blood Plasma Blood plasma is the liquid portion of blood. Consists of: Mostly water Mixture of proteins Albumins Globulins Fibrinogen Nutrients Amino acids Glucose Nucleotides Lipids Gases Electrolytes Waste products
38 Apply Your Knowledge Does the pulmonary arteries carry high levels oxygen or low levels of oxygen in the blood?
39 Answer Apply Your Knowledge - Answer Pulmonary arteries carry oxygen poor blood Does pulmonary arteries carry high levels oxygen or low levels of oxygen in the blood?
40 ABO Blood Group Blood TypeAntigen Present Antibody Present Blood that can be received AABA & 0 BBAB & O AB NoneA, B, AB, & O 0NoneA & BO
41 RH Blood Group Rh positive Rh positive person has red blood cells that contain the Rh antigen Rh negative Rh negative red blood cells do not contain the Rh antigen Rh positive blood Rh positive blood is given to Rh negative person and antibodies form Second time this occurs antibodies Second time this occurs antibodies will bind to the donor cells and agglutination will occur
42 Apply Your Knowledge What type(s) of blood could a patient who has type B blood receive without complications?
43 Answer Apply Your Knowledge - Answer Type B & O What type(s) of blood could a patient who has type B blood receive without complications?
44 The Lymphatic System A network of connecting vessels that collect fluids between cells Lymphatic vessels then return this fluid (called lymph) to the blood stream Picks up lipids from the digestive organs and transports them to the blood stream Defend our bodies against disease- causing agents called pathogens
45 The Lymphatic System Lymph Nodes Lymph Nodes digest unwanted pathogens in the lymph start an immune response against the pathogen Thymus production of T lymphocytes & hormone called thymosin Spleen Spleen largest lymphatic organ spleen also removes worn out red blood cells from the circulation
46 Lymph Fluid Tissue fluid that has entered a lymphatic capillary Pushed through the vessels by the squeezing action of skeletal muscles Contain valves that prevent the backflow of lymph Lymph Node
47 Diseases and Disorders of the Circulatory System Anemia Anemia - a condition in which a person does not have enough red blood cells or hemoglobin in blood to carry an adequate amount of oxygen to body cells Aneurysm Aneurysm - defined as a ballooning of an artery wall that results when the wall of the blood vessel becomes weak
48 Diseases and Disorders of the Circulatory System (cont.) Carditis - an inflammation of the heart most commonly referred to as endocarditis, myocarditis, or pericarditis depending on the layer of the heart affected Congestive heart failure - a slowly developing condition in which the heart weakens over time.
49 Coronary artery disease Coronary artery disease – (atherosclerosis) characterized by narrowing of coronary arteries Heart arrhythmias Heart arrhythmias – abnormal heart rhythms in which the heart beats too quickly (tachycardia) or too slowly (bradycardia) Heart attack Heart attack (myocardial infarction) – damage to cardiac muscle that is due to a lack of blood supply Diseases and Disorders of the Circulatory System (cont.)
50 Hypertension (high blood pressure) Hypertension (high blood pressure) defined as consistent resting blood pressure 140/90 mm Hg or higher Leukemia Leukemia a condition in which the bone marrow produces a large number of white blood cells that are not normal Murmurs Murmurs simply defined as abnormal heart sounds Diseases and Disorders of the Circulatory System (cont.)
51 Sickle cell anemia Sickle cell anemia – a condition in which abnormal hemoglobin causes red blood cells to change to a sickle (crescent) shape Thrombophlebitis Thrombophlebitis – a condition in which a blood clot and inflammation develop in a vein Varicose veins Varicose veins – dilated veins and are usually seen in the legs Diseases and Disorders of the Circulatory System (cont.)
52 Apply Your Knowledge The doctor has told your patient she has anemia. How would you explain this to the her?
53 Answer Apply Your Knowledge - Answer Anemia is a condition in which a person does not have enough red blood cells or hemoglobin in blood to carry an adequate amount of oxygen to body cells. The doctor has told your patient she has anemia. How would you explain this to the her?
54 Summary Medical Assistant Knowledge of the circulatory system will assist you in providing care for the patient with diseases and disorders of the circulatory system. You must have knowledge of this system especially when assisting the physician during his examination of the circulatory system.