Anatomy and Physiology

1
Anatomy and Physiology

• The Circulatory System Part I The Blood
• Community Education
• Chapter 13
• Mr. Kestner

2
Blood Composition

• Blood often called tissue because it contains
  many types of cells
• Approximately 5 6 liters of blood in adult
• Approximately 8 of total body weight
• Blood continuously circulates through body
• Has a normal pH of 7.35 7.45 (slightly basic,
  or alkaline)

3
Blood Composition

• Transports
• O2 from lungs to body
• CO2 from body to lungs
• nutrients from digestive tract to cells
• metabolic and waste products from body to organs
  of excretion
• heat produced by various body parts
• hormones from endocrine glands to body organs

4
Blood Composition

• Made of fluid called plasma and formed or solid
  elements called blood cells
• Plasma
• Viscous, approximately 55 of blood
• Approximately 90 H2O, with many dissolved, or
  suspended, substances
• Blood proteins
• Fibrinogen and prothrombin (clotting)
• Nutrients
• Vitamins, carbs, proteins, minerals (K, Ca,
  Na)
• Gases
• CO2, O2
• Metabolic waste
• Hormones and enzymes

5
Blood Cells

• Three main kinds of blood cells
• Erythrocytes
• Leukocytes
• Thrombocytes

6
Erythrocytes

• Red blood cells
• Produced in red bone marrow at a rate of 1
  million per minute
• Live approximately 120 days before being broken
  down by liver and spleen
• Approx. 4.5 to 5.5 million erythrocytes per cubic
  millimeter ( 1 drop), or 25 trillion in body
• Mature form circulating in blood lacks nucleus
  and is shaped like disc with a thinner central
  area
• Contains hemoglobin

7
Hemoglobin

• Complex protein composed of the protein molecule
  called globin and the iron compound called heme
• Carries both O2 and CO2
• When carrying O2, hemoglobin gives blood
  characteristic red color
• When blood contains a lot of O2, it is bright
  red when blood contains less O2 and more CO2, it
  is a much darker red with a bluish cast

8
Leukocytes

• White blood cells
• Not as numerous as erythrocytes
• Formed in bone marrow and lymph tissue
• Usually live about 3 9 days
• Normal count is 5 10 thousand per cubic
  millimeter of blood ( 1 drop)
• Can pass through capillary walls into body tissue
• Main function is to fight infection
• Some do this by engulfing, ingesting, and
  destroying pathogens, or germs a process called
  phagocytosis

9
Leukocytes

• Neutrophils
• phagocytize bacteria by secreting an enzyme
  called lysozyme
• Eosinophils
• remove toxins and defend the body from allergic
  reactions by producing antihistamines
• Basophils
• participate in the bodys inflammatory response
  produce histamine, a vasodilator, an
  anticoagulant
• Monocytes
• phagocytize bacteria and foreign materials
• Lymphocytes
• Provide immunity for the body by developing
  antibodies protect against formation of cancer
  cells

10
Thrombocytes

• Also called platelets
• Formed in bone marrow and live for about 5 9
  days
• Normal count is 250,000 to 400,000 per cubic
  millimeter of blood ( 1 drop)
• Important for the clotting process
• When blood vessel is cut, thrombocytes collect at
  site to form sticky plug

11
Thrombocytes

• Secrete chemical, serotonin, which causes blood
  vessel to spasm and narrow, decreasing flow of
  blood
• At same time, release an enzyme called
  thromboplastin, which acts with Ca and other
  substances in plasma to form thrombin
• Thrombin acts on blood protein fibrinogen to form
  fibrin, a gel-like net of fine fibers that traps
  erythrocytes, platelets, and plasma to form a
  clot
• Effective method for controlling bleeding in
  smaller vessels
• Large vessel cuts, rapid blood flow can interfere
  with clotting

12
Blood Groups

• ABO Blood Group
• A presence or absence of two major antigens on
  the RBC membrane
• Antigen A
• Antigen B
• Blood contains one of four combinations
• Only A
• Only B
• Both A and B
• Neither A nor B

13
Blood Types

• Each blood type has antibodies
• Formed during infancy against antigens
• Type A has anti-B antibody
• Type B has anti-A antibody
• Type AB has neither antibody
• Type O has both anti-A and anti-B antibodies

14
Rh Factor

• Named after the Rhesus monkeys
• Found also in humans later
• Identified as antigen D
• If antigen D present
• Rh positive
• If antigen D is not present
• Rh negative
• Most Americans are Rh positive

15
Rh Factor

• Unlike ABO antibodies, anti-Rh antibodies do not
  develop spontaneously in infancy
• Instead, only developed in Rh negative person if
  he/she receives a blood transfusion with Rh
  positive blood
• Then antibodies are produced
• If second mismatched transfusion occurs, blood
  will agglutinate and cells will rupture

16
Rh Factor

• Similar problem occurs when Rh negative mother
  carries an Rh positive baby
• First pregnancy is usually normal because mother
  may now be sensitized and produce anti-Rh
  antibodies
• These antibodies will cross placenta and destroy
  blood of second baby or subsequent pregnancies
• Shots of RhoGAM are given to prevent it

17
Anatomy and Physiology

• The Circulatory System Part II
• The Heart and Vessels
• Community Education
• Chapter 14
• Mr. Kestner

18
The Circulatory System

• Also known as the cardiovascular system
• Often referred to as the transportation system
  of the body
• Consists of
• Heart
• Blood vessels
• Blood
• Transports O2 and nutrients to cells
• Carries CO2 and metabolic materials away

19
The Heart

• A muscle, a hollow organ often called the Pump
• Approximately the size of a closed fist
• Located in the mediastinal cavity
• Between the lungs
• Behind the sternum
• Above the diaphragm

20
The Heart

• Three layers of tissue form the heart
• Endocardium inside layer of heart, continuous
  with inside of blood vessels
• Myocardium thickest layer, the muscular middle
  layer
• Pericardium double layered outside membrane (or
  sac), a lubricating fluid fills space between
  layers to prevent friction
• The Septum is a muscular wall that separates the
  heart into right and left sides

21
The Heart

• The heart is divided into 4 chambers
• Right atrium receives blood from the body
• Right ventricle receives blood from RA, then
  pumps it to the lungs for oxygen
• Left atrium receives blood from the lungs
• Left ventricle receives blood from the LA, then
  pumps it to the body
• http//www.smm.org/heart/heart/pumping.htm

22
The Heart

• One-way valves in the heart chambers keep the
  blood flowing in the right direction
• Tricuspid valve located between RA and RV
• Pulmonary valve located between RV and
  pulmonary artery, a blood vessel that carries
  blood to the lungs
• Mitral valve located between LA and LV
• Aortic valve located between LV and aorta, the
  largest artery in the body
• http//www.smm.org/heart/heart/steth.htm

23
Cardiac (Heartbeat) Cycle

• Right left sides are separated by septum
• Both sides work together in cyclic manner
• Cycle consists of brief period of rest
• Diastole
• Followed by period of ventricular contraction
• Systole

24
Cardiac (Heartbeat) Cycle

• At start of cycle, atria contract and push blood
  into the ventricles
• The atria then relax, and blood returning from
  body enters the ____ atrium, while blood
  returning from the lungs enters the ___ atrium

25
Cardiac (Heartbeat) Cycle

• At start of cycle, atria contract and push blood
  into the ventricles
• The atria then relax, and blood returning from
  body enters the right atrium, while blood
  returning from the lungs enters the left atrium
• As atria are filling, systole begins and the
  ventricles contract

26
Cardiac (Heartbeat) Cycle

• The ____ ventricle pushes blood into the
  pulmonary artery, sending blood to the lungs for
  oxygen
• The ___ ventricle pushes blood into the aorta,
  sending blood to all other parts of the body

27
Cardiac (Heartbeat) Cycle

• The right ventricle pushes blood into the
  pulmonary artery, sending blood to the lungs for
  oxygen
• The left ventricle pushes blood into the aorta,
  sending blood to all other parts of the body

28
Cardiac (Heartbeat) Cycle

• The blood in the right side of the heart is low
  in oxygen and high in carbon dioxide
• When this blood arrives in the lungs, the carbon
  dioxide is released into the lungs, and oxygen is
  taken into the blood
• This oxygenated blood is then carried to the left
  side of the heart by the pulmonary veins
• The blood in the left side of the heart is high
  in oxygen and low in carbon dioxide, and ready to
  be pumped to the body

29
Blood Vessels

• Blood is carried through body in blood vessels
• The heart and blood vessels form a closed system
• There are three main types of blood vessels
• Arteries
• Veins
• Capillaries

30
Arteries

• Carry blood away from heart
• Aorta is the largest artery in body
• Immediately begins branching into smaller
  arteries
• Smallest branches of arteries called arterioles
• they join with capillaries
• More muscular and elastic than other blood
  vessels
• they receive blood as it is pumped from heart

31
Veins

• Carry blood back to the heart
• Superior/inferior vena cava are largest
• Superior vena cava brings blood from _ body
• Inferior vena cava brings blood from _ body

32
Veins

• Carry blood back to the heart
• Superior/inferior vena cava are largest
• Superior vena cava brings blood from ? body
• Inferior vena cava brings blood from ? body
• Both vena cavae drain into the right atrium
• Smallest branches of veins called venules
• Thinner and have less muscle tissue
• Most contain valves to prevent backflow

33
Capillaries

• Connect arterioles with venules
• Have thin walls containing only one layer of
  cells
• Thin walls allow O2 and nutrients to pass to
  cells and allow CO2 and metabolic waste from
  cells to enter capillaries

34
Anatomy and Physiology

• The Circulatory System Part III
• The Conduction Pathway
• Community Education
• Chapter 14
• Mr. Kestner

35
Conductive Pathway

• Electrical impulses originating in the heart
  cause the cyclic contraction of the muscle
• Sinoatrial (SA) node
• Atrioventricular (AV) node
• Bundle of His
• Right bundle branch
• Left bundle branch
• Purkinje fibers

36
Sinoatrial (SA) Node

• Group of nerve cells located in the right atrium
• Considered the pacemaker
• Sends out electrical impulse, which spreads out
  over the muscles in the atria
• Atria muscles then contract and push blood into
  ventricles
• After impulse passes through atria, it reaches AV
  node

37
Atrioventricular (AV) Node

• Group of nerve cells located between the atria
  and ventricles
• Sends electrical impulse through bundle of His

38
Bundle of His

• Nerve fibers in the septum
• Divides into a right bundle branch and a left
  bundle branch
• Carries impulse down through ventricles
• Bundle branches further subdivide into Purkinje
  fibers

39
Purkinje Fibers

• A network of nerve fibers throughout ventricles
• This way, electrical impulse reaches all the
  muscle tissue in ventricles, and ventricles
  contract

40
Conduction

• Electrical conduction pattern occurs
  approximately every 0.8 seconds
• Movement of electrical impulse can be recorded on
  an electrocardiogram (ECG)
• Used to detect abnormal activity or disease
• If something interferes with normal electrical
  conduction pattern of the heart, arrhythmias occur

41
Arrhythmias

• Abnormal heart rhythms
• Can be mild to life-threatening
• Example
• Early contraction of atria (Premature Atrial
  Contraction PAC), can occur in anyone and
  usually goes unnoticed
• Ventricular fibrillation, in which ventricles
  contract at random without coordination,
  decreases or eliminates blood output and causes
  death if not treated

42
Arrhythmias

• Cardiac monitors and ECGs are used to diagnose
  arrhythmias
• Treatment depends on type and severity of
  arrhythmia
• Life-threatening fibrillations are treated with a
  defibrillator, a device that shocks the heart
  with an electrical current to stop the
  uncoordinated contraction and allow the SA node
  to regain control

43
Arrhythmias

• Sometimes external or internal pacemakers are
  used to regulate rhythm
• A small battery-powered device with electrodes
  threaded through vein and positioned in right
  atrium and apex of right ventricle
• It monitors hearts activity and delivers an
  electrical impulse to stimulate contraction
• Fixed pacemakers deliver at predetermined rate
• Demand pacemakers deliver only when heart is not
  responding correctly

44
Anatomy and Physiology

• The Circulatory System Part IV
• Diseases and Abnormal Conditions
• Community Education
• Chapters 13 and 14
• Mr. Kestner

45
Diseases and Abnormal Conditions

• Anemia
• Iron deficiency
• Aplastic
• Pernicious
• Sickle Cell
• Aneurysm
• Arteriosclerosis
• Atherosclerosis

46
Diseases and Abnormal Conditions

• Congestive Heart Failure
• Embolus
• Hemophilia
• Hypertension
• Leukemia
• Myocardial Infarction
• Phlebitis
• Varicose Veins

47
Anemia

• An inadequate number of RBC, hemoglobin, or both
• Symptoms include pallor, fatigue, dyspnea, and
  tachycardia
• Types of anemia include
• Iron deficiency anemia
• Inadequate amount of iron to form hemoglobin
• Aplastic anemia
• Result of injury to bone marrow
• Pernicious anemia
• Abnormally large and inadequate RBCs due
  inadequate absorption of Vitamin B12
• Sickle cell anemia
• Inherited, results in production of
  crescent-shaped RBCs

48
Aneurysm

• A ballooning out of, or a saclike formation on an
  artery wall
• Disease, congenital defects, and injuries can
  cause this defect
• Many are asymptomatic
• Common sites are cerebral, aortal, and abdominal
  arteries
• If aneurysm ruptures, hemorrhage occurs which can
  lead to death
• Treatment involves removal and replacement of
  blood vessel area with plastic graft or another
  vessel

49
Arteriosclerosis

• Hardening or thickening of the arterial walls
• Results in loss of elasticity and contractility
• Commonly occurs as a result of aging
• Causes hypertension
• Can lead to aneurysm or cerebral hemorrhage

50
Atherosclerosis

• Occurs when fatty plaques (usually cholesterol)
  are deposited on arteries
• Narrows arterial opening, which reduces or
  eliminates blood flow
• If plaque breaks loose, it can circulate through
  bloodstream as an embolus
• Treatment
• Low cholesterol diet, medications, and exercise
  are used to prevent atherosclerosis
• Angioplasty may be used to remove or compress the
  deposits, or stent insertion to allow blood flow
  may be recommended
• Bypass surgery is used when artery is completely
  blocked http//www.cvassoc.com/images/serviceimag
  es/Stent.html

51
Congestive Heart Failure (CHF)

• Heart muscle does not beat adequately to supply
  the body with needed blood
• May involve right side or left side of heart
• Symptoms include
• Edema dyspnea pallor jugular distention weak,
  rapid pulse cough with pink, frothy sputum
• Treatment
• Cardiac drugs diuretics elastic support hose
  O2 therapy bedrest and/or low-sodium diet

52
Embolism

• A foreign substance circulating in the
  bloodstream
• Can be air, a blood clot, bacterial clumps, a fat
  globule, or other similar substances
• When embolus enters artery or capillary too small
  for passage, blockage of blood vessel occurs

53
Hemophilia

• Inherited disease that occurs almost exclusively
  in males, but can be carried by females
• Because of lack of plasma protein required for
  clotting process, blood is unable to clot
• Minor cut can lead to prolonged bleeding
• Minor bump can cause internal bleeding
• Treatment involves transfusing whole blood or
  plasma, and administering the missing protein
  factor (Factor VIII)

54
Hypertension (HTN)

• High blood pressure with a systolic pressure
  gt 140 and a diastolic pressure gt 90
• Risk factors
• Family history, race, age, obesity, stress,
  smoking, and diet high in saturated fat
• Controlling HTN
• No cure
• Usually controlled with antihypertensive drugs,
  diuretics, limited stress, avoiding tobacco,
  and/or low-sodium or low-fat diet
• If not treated, HTN can cause permanent damage to
  heart, blood vessels, and kidneys

55
Leukemia

• A malignant disease of the bone marrow
• Results in high number of WBCs
• Different types of leukemia, some acute and some
  chronic
• Symptoms include
• Fever, pallor, swelling of lymph, fatigue,
  anemia, bleeding gums, excessive bruising, and
  joint pain
• Treatment methods vary but may include
• Chemotherapy, radiation, and/or bone marrow
  transplant

56
Myocardial Infarction (MI)

• Coronary artery blockage
• Affected tissue dies and is called infarct
• Death can occur immediately
• Symptoms include
• Severe crushing pain (angina pectoris), that
  radiates to the arm, neck, and jaw pressure in
  the chest perspiration and cold, clammy skin
  dyspnea change in BP

57
Myocardial Infarction (MI)

• Treatment
• If heart stops, CPR should be initiated
  immediately
• Immediate treatment with a thrombolytic or
  clot-busting drug may open the blood vessel and
  restore blood flow to the heart
• Must be used within first several hours
• Additional treatment methods include complete
  bedrest, pain meds, vasodilators, O2 therapy,
  anticoagulants, and control of arrhythmias
• Long-term care includes control of BP,
  low-cholesterol diet, tobacco and stress
  avoidance, regular exercise, and weight control

58
Phlebitis

• Inflammation of vein, frequently in the leg
• If a thrombus, or clot, forms, condition is
  called thrombophlebitis
• Symptoms include
• Pain edema erythema and discoloration at the
  site
• Treatment methods include
• Anticoagulants pain meds elevation of affected
  area antiembolism or support hose and, if
  necessary, surgery to remove clot

59
Varicose Veins

• Dilated, swollen veins that have lost elasticity
  and cause decreased blood flow
• Frequently occur in legs and result from
  pregnancy, prolonged sitting or standing, and
  hereditary factors
• Treatment methods include exercise, antiembolism
  or support hose, avoidance of prolonged sitting
  or standing, and tight-fitting or restrictive
  clothing
• In severe cases, surgery can be performed to
  remove the vein