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Objectives for the Cardiovascular System
1. State the function of the blood
2. Compare the different blood cells and their function
3. Describe the structure of the Red Blood Cells (RBC)
4. List the cells found in the granulocytes and the agranulocytes with their function
5. Explain the different blood types and their antigens
6. Discuss the steps of the hemostasis process
7. Name the 2 circulatory circuits in the body
8. Describe the external anatomy of the heart
9. List the major arteries and veins of the heart
10. Name the 4 valves of the heart and what part they play in the cardiac cycle
11. Describe the make-up of the cardiac muscle and how it is different from skeletal
12. List the nodal cells of the heart
13. Review the terminology in cardiac dynamics
14. Compare the affects of the Sympathetic and Parasympathetic nervous system control
15. Compare the differences in the structure of artery, veins, capillaries
16. Review the principles of diffusion, osmosis, hydrostatic pressure, capillary
osmotic pressure, interstitial fluid colloid osmotic pressure, net
filtration pressure, plasma colloid osmotic pressure
17. Discuss the affects of neural autoregulation, & hormones on the vascular system
18. Explain the pathway of the blood as it travels through the body including the
pulmonary circulation
19. Describe the differences in the lymph system and its function
20. Explain the differences in the fetal circulation
21. Discuss the process of shock, naming the types of shock & its complications
22. Discuss the cardiovascular problems that occur with Taser Gun injury
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Cardiovascular System – Lecture 4
I. Blood
A. Function of Blood
1. Transportation
2. Regulation
3. Restriction
4. Defense
5. Stabilization
B. Composition(Plasma + Formed Elements)
1. Cells
a. Plasma ( 46-63% = plasma proteins, solutes, water)
1) Differences between plasma & interstitial fluid
2) Plasma Proteins – synthesized by liver
a) Albumins (60%) – osmotic pressure
b) Globulins (35%)
(1) Immunoglobulin (antibodies)
(2) Transport Proteins
c) Fibrinogen (4%)
3) Solutes
a) Electrolytes (Na, K, Cl)
b) Organic nutrients (acids, glucose, amino acids)
c) Organic wastes (urea, bilirubin)
b. Red Blood Cells (erythrocytes)
1) Structure of RBC
a) Concaved – large surface area
b) Lack of mitochondria, ribosomes, nucleus
(No mitosis or protein synthesis)
2) Hemoglobin Structure & Function
a) Hemoglobin (Hb) – oxygen carrier part
b) Heme unit – single molecule hold iron ion
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(1) Weak bond
(2) Depends on conditions
c) H&H different male & female
(1) Due to androgens
(2) Estrogen inhibits RBC production
d) Types
(1) HbA (adult)
(2) HbF (fetal)
3) Life span (120 days)
a) Rupture or destroyed by phagocytic cells
(Hemolyze)
b) 1% replaced daily
4) Hemoglobin Conservation & Recycling
a) Phagocytic cells of liver, spleen, & bone
monitor status of RBC’s
(1) Disassembled into amino acids
(2) Biliverdin
(3) Bilirubin
(4) Jaundice
(5) Transferrin
b) Dietary issues
5) Red Blood Cell Formation (erythropoiesis)
a) Bone Marrow
(1) Red – long bones
(a) Vertebrae, sternum, ribs, skull,
scapulae, pelvis, proximal
limb bones
(2) Yellow – fatty tissue
b) From Immaturity to Maturity
(1) Erythroblasts (immature RBC)
(2) Reticulocyte – 2 days in marrow to
circulation
(3) Mature RBC post 24 hours in circulation
c) Hormone Regulation
(1) Erythropoietin (EPO) or erythropoiesis-
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stimulating hormone – kidneys
(a) Stimulates division of
Erythroblasts
(b) Speeds up maturity of RBC’s
6) Destruction of RBC
a) Can't synthesize protein for growth & repair
b) Phagocytic cells spleen, liver, bone marrow
& marrow
c) AA & iron salvage & reuse
d) Insoluble/ soluble
e) Plasma hemoglobin
f) Excessive destruction
c. White Blood Cells (leukocytes) - acute circulation periods
1) Groups
a) Granulocytes
(1) Neutrophils (70% or 55-65%)
(a) First arrivals
(b) Active eaters
(c) Short life – 12 hours
(2) Eosinophils (2-4%) – 2 lobes
(a) Allergic reactor
(3) Basophils – (1% or 0.5%)
(a) Granules secrete heparin &
histamine
(b) Interstitial Fluid attacker
b) Agranulocytes
(1) Monocytes (2-8%) – kidney bean
nucleus – large cell
(a) Phagocytic guys
(b) Chemical attraction
(c) Fibroblasts
(d) Activate lymphocytes
(e) Tissues = macrophages
[1] Histocyte
[2] Microglial
[3] Kupffer
(2) Lymphocytes – (20-30%)
(a) T cells – attackers & stimulator
(b) B cells – antibodies
(c) Natural killer cells (NK) –
surveillance with destruction
own body tissue
(d) Cluster of differentialtion (CD)
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2) Characteristics of WBC’s
a) Amoeboid movement
b) Diapedesis – squeeze
c) Positive chemotaxis
d) Phagocytosis
d. Platelets
1) Megakaryocytes “REALLY BIG CELLS”
a) Shed platelets (packets) – thrombocytes
(1) 10-12 days life
(2) Initiate blood clotting & close vessels
C. Blood Types (surface antigens of membrane)
1. Important surface antigens
a. Type A = A only antigens; B antibodies
b. Type B = B only antigens; A antibodies
c. Type O = neither A nor B antigens but A&B antibodies
d. Type AB = both A and B antigens but no A&B antibodies
e. Rh
1) Positive – present
2) Negative – absent
2. Compatible bloods
a. Plasma contains antibodies
b. Persons’ immune system ignores antigens on surface
c. Incompatible bloods cause agglutination (clumping)
d. Emergency situation
1) Type O – has neither A nor B antigens or Rh
(universal donor)
2) Type AB – antigen A & B; lack antibodies A&B
(universal recipient)
3. Blood banking
a. Red Blood Cells (packed cells)
b. Plasma (liquid portion) – cryoprecipaitate – clotting
c. Platelets – abnormal platelet function
d. White Blood Cells – infections unresponsive to antibiotic
e. Factor transfusions
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D. Hemostasis – blood clotting
1. Steps
a. Vascular
b. Platelet
c. Coagulation
2. Process
a. Pathways
1) Extrinsic (tissue; external damage)
2) Intrinsic (internal; exposure to collagen fibers)
3) Common (merging of extrinsic/intrinsic at factor X)
a) Prothrombin to thrombin
b) Fibrinogen to fibrin
3. Clot Retraction & Removal
a. Retraction – reduces size
b. Fibrinolysis = plasminogen to plasmin to dissolve via
tissue plasminogen activator (TPA) from tissues
c. Medication
1) Clot busters – Thrombolytic therapy (TPA,
Streptokinase)
2) Antiplatelet therapy (ASA, Reopro, Aggrastat)
3) Anticoagulation therapy (Heparin, Lovenox)
II. Circulatory System
A. Circuit (arteries, veins, capillaries)
1. Pulmonary carry blood to and from pulmonary system
2. Systemic – carry blood from heart to body
B. Anatomy of Heart
1. Structure External (angle position; mid-sternal)
a. Pericardial cavity
1) Visceral or epicardium
2) Parietal
b. Epicardium
c. Myocardium
1) Cardiac muscle cell
a) Cardiocyte
b) Dependent on aerobic metabolism
c) Intercalated discs with tight junctions
d) Striated muscles but involuntary
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d. Endocardium
e. Apex
f. Base
g. Auricla
h. Coronary sulcus
i. Interventricular sulcus
2. Internal (4 chambers)
a. Septum
1) Interventricular
2) Interatrial
b. Vessels
1) Superior vena cava
2) Inferior vena cava
3) Aorta
4) Pulmonary arteries
5) Pulmonary veins
6) Coronary arteries – supply the cardiac muscles
origin aortic sinus ascending aorta; ANS; O2 needs
60-80%; fill in diastolic phase
a) Right Coronary artery
(1) Marginal branch
(2) Posterior interventricular branch
c) Left Coronary artery
(1) Circumflex branch
(2) Anterior Interventricular branch
7) Coronary veins
a) Great cardiac vein- carries away from capillary
b) Coronary sinus – veins drain into; open to R
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atrium near inferior vena cava
c) Small cardiac vein
d) Middle cardiac vein – carry away from capillary
e) Posterior cardiac vein
f) Anterior cardiac vein
c. Valves – leaflets prevent backflow
1) Atrioventricular (AV valves) – supported by papillary
muscles; projected from ventricular wall; chordae
tendineae – support & attach valves
a) Tricuspid
b) Mitral ( Bicuspid)
2) Semilunar Valves
a) Pulmonic valve
b) Aortic valve
d. Differences between Right & Left Ventricles
1) Pressure
2) Blood
3) Muscles
C. Cellular Make-up
1. Cardiac Muscle (cardiocytes)
a. Small, single nucleus
b. Myofibril & shortening with contractions
c. Abundant mitochondria & myoglobin (aerobic)
d. Intercalated discs (contact sites)
e. Action potential quick with tight connections
f. Automaticity
2. Fibrous Skeleton Tissue (connective tissue)
a. Support
b. Surround
c. Limits overexpansion
3. Contractile Cells
a. Action potential in sarcolemma
1) Phase 0
2) Phase 1
3) Phase 2
4) Phase 3
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5) Phase 4
b. Quick depolarization/repolarization
4. Conduction System
a. Nodal Cells
1) Pacemaker cells
a) Sinoatrial node (SA node) – 60-100/min
b) Atrioventricular node (AV node) – 40-60/min
c) AV Bundle (Bundle of His) – conducts impulse
to branches
d) R & L bundle branches
e) Purkinje fibers – 20-30/min ventricles
b. Electrocardiogram – electrical recorded impulse
1) P wave
2) PR interval
3) QRS wave
4) ST segment
5) T wave
6) U wave
5. Cardiac cycle (contraction & relaxation)
a. Phases
1) Systole
2) Diastole
b. Heart Sounds
1) First (AV closure)
2) Second ( Semilunar closure)
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3) Third & Fourth (blood flow & atrial contraction)
c. Pressure changes
1) Isovolumetric contraction period – close AV valves
a) Onset of systole
2) Ejection period (60% SV ejected in first quarter cycle)
3) Isovolumetric relaxation (AV valves open)
6. Cardiac Dynamics
a. Terminology
1) Stroke volume (SV) – amount ejected from heart
2) Cardiac Output (CO) - amount blood pumped from
ventricles/min; varies (“normal” 3.5- 8.0 L/min)
a) CO = SV x HR
3) Preload – volume in heart prior to contraction
4) Afterload – pressure heart works against in aorta
5) Cardiac contractility – ability of heart to change force of
contraction without changing the length
6) Heart rate – number times per minute heart beats
7) Systemic vascular resistance (SVR) - pressure in
systemic vessels
8) Absolute Refractory periods – no stimulus would cause
dpolarization
9) Relative refractory periods – large enough stimulus
would cause a depolarization
10) Arrhythmias
a) Heart Block – AV node blocked
b) Premature
(1) Atrial contraction
(2) Ventricular
d) Fibrillation
(1) Ventricular
(2) Atrial
d) Tachycardia
(1) Atrial
(2) Ventricular
(3) Supraventricular
(4) Junctional
e) Bradycardia
(1) Sinus
(2) Junctional
f) Flutter
11) Coronary artery disease
a) Atherosclerosis
b) Arteriosclerosis – fat in artery wall
12) Acute Coronary Syndrome (MI)
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13) Reperfusion – blood restored to cardiac muscle
14) Revascularization – vessel reopening
15) Defibrillation – electrical interruption of arrhythmia
7. Affects of Autonomic Nervous System – changes in HR & BP
(similar to CNS; gap junctions; Neurotransmitters –
ANS = Ach
Catacholamine – norepinephrine, epinephrine, dopamine
alpha 1
alpha 2
beta 1
beta 2
a. Sympathetic – norepinephrine/epinephrine via brain stem axons
1) Originate in vasomotor center of brain stem
2) Tonic activity (constricted)
b. Parasympathetic (Ach) via vagus nerve
1) Regulation heart but NOT blood vessels
8. Medulla oblongata control
a. Baroreceptors = pressure changes
1) Aortic – aortic sinuses heart
2) Carotid sinus – internal carotid of neck
3) Atrial – wall R atrium
b. Chemoreceptor = chemical O2 & CO2
1) Activation with drop in pH & O2 or CO2 rise
c. Hypothalamus = emotional center
III. Blood Vessels (arteries, arterioles, capillaries, venules, veins)
A. Structure (both arteries & veins)
1. Layers
a. Tunica interna – endothelial lining
1) Semipermiable
2) Blood clotting
3) Hormonal control
4) Immune regulation
5) Regulation blood flow
6) Nitric Oxide & endothelins
b. Tunica media – smooth muscle
1) Synthesize collagen & elastin
2) Growth factors – vascular repair
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c. Tunica externa
B. Types of Vessels
1. Arteries (oxygenated blood carried away from the heart)
a. Elastic
b. Muscular – elastic (large), Muscular (medium), arterioles
c. High pressure
d. Oxygenated blood
2. Capillaries (exchange units)
a. Thin walled, sometimes single layers
b. Slower movement of flow
c. Gaps
d. Capillary beds – interconnected network
1) Precapillary sphincter
3. Veins
a. Low pressure
b. Unoxygenated blood
c. Valves present
d. Holding capacity
e. Muscular compression
f. Respiratory pump
C. Pressure (Long & Short Term control) = pressure & resistance
1. Systolic pressure – peak during ventricular systole
2. Diastolic pressure- pressure in vessels ventricular diastole end
3. Pulse pressure – difference between systolic and diastolic pressure
4. Capillary pressure
a. Exchange
1) Diffusion
2) Osmosis
3) Hydrostatic pressure
4) Capillary osmotic pressure
5) Interstitial fluid colloid osmotic pressure
6) Net filtration pressure
7) Plasma colloid osmotic pressure – move fluid inward
5. Long & Short Term Regulation
a. Long – kidney (over months)
b. Short – (temporary over minutes)
1) Hormonal
2) Neural
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D. Vascular Regulation
1. Autoregulation
a. Vasodilators
b. Vasoconstrictors
2. Neural Control
a. Cardiac Centers & Vasomotor Centers – medulla oblongata
1) Baroreceptors
2) Chemoreceptors
3) Higher Centers
b. Autonomic Nervous System
1) Sympathetic – constrictors/relaxation – final pathway
for smooth muscle tone of vessels
a) Release neurotransmittors
2) Parasympathetic – little effect on vascular system
3. Hormones
a. Endocrine = long & short term control
1) Angiotensin II (potent vasoconstrictor)
a) Post rennin release by kidney from fall BP
b) Conversion Angiotensinogen to angiotensin II
c) Stimulates ADH
2) Antidiuretic Hormone (ADH) – sodium & water
a) Pituitary gland release
3) Erythropoietin – released adrenal in low O2 makes RBC
4) Atrial Natriuretic Peptide – produced in atrial cells
a) Promotes loss of Na ions & water
b) Reduces thirst
c) Blocks E & NE
d) Stimulates peripheral vasodilation
e) Comes from excess stretch of muscle
E. Pulmonary Circulation
1. Process
a. Enter via pulmonary arteries to lungs, oxygenated, return heart
via pulmonary veins
b. Exchange occurs at alveoli & capillary network
F. Systemic Circulation
1. Arteries
a. Aorta (ascending, aortic arch, descending)
b. Aortic arch (brachicephalic, subclavian R & L, Carotid)
b. Subclavian (vertebral, axillary, brachial, ulna, radial, palmar
digital)
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1) Internal thoracic
c. Carotid (internal, external, carotid sinus, basilar, cerebral
arterial)
1) Facial, maxillary, temporal
d. Head (Basilar, middle, anterior)
1) Circle of Willis (anterior communicating & cerebral
posterior communicating & cerebral)
e. Descending
1) Pericardial
2) Bronchial
3) Mediastinal
4) Intercostals
5) Celiac trunk
6) Splenic
7) Common hepatic
8) Suprarenal
9) Renal R & L
10) Superior mesenteric
11) Gonadal
12) Inferior mesenteric
13) Lumbar
14) Common iliac
15) External iliac
16) Internal iliac
17) Femoral
a) Popliteal
b) Anterior tibial
c) Posterior tibial
d) Peroneal (dorsalis pedis & plantar arch)
2. Veins
a. Head & Neck
1) Dural sinuses
2) Jugular
a) Internal
b) External
3) Vertebral veins
4) Superior Vena Cava (blood chest, neck, head, upper
limbs)
b. Limbs & chest
1) Digital veins
2) Cephalic Vein
3) Basilic vein
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4) Radial & ulna
5) Brachial
6) Axillary
7) Subclavian
8) Brachiocephalic
9) Azygos – thoracic chest to SVC to atrium
c. Inferior Vena Cava – below diaphragm
1) Plantar
2) Anterior tibial
3) Posterior tibial
4) Peroneal
5) Dorsal venous arch – superior foot
6) Great saphenous & small saphenous
7) Popliteal
8) Femoral
9) Iliac (external & internal
10) Lumbar (gonadal, renal, suprarenal, phrenic, hepatic)
d. Hepatic Portal (drains celiac, superior & inferior mesenteric
artery)
(liver cells oxygenated by hepatic artery)
1) Substances from digestion
2) Carried by capillary beds without mixing
3) Delivery to liver
4) Liver capillaries
5) Hepatic veins
6) Inferior vena cava
3. Lymph System
a. Drains excess fluid
b. Infection process
c. Parallels vascular system
d. Lack tight junctions; carry large substances (proteins &
nutrients)
e. Empty into R & L thoracic ducts
f. Thoracic ducts empty into subclavian & internal jugular
G. Problems
1. Aneurysm- weakness of vessel wall
2. Acute Pulmonary Embolism
3. Occlusion
4. Infection
5. Trauma
6. Failure
7. Disease
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H. Fetal Circulation (no lungs to oxygenate, no digestion) – placenta function
1. Umbilical (2 arteries to placenta, 1 vein from with oxygen & nutrient)
a. Umbilical vein drains to capillaries in liver to IVC via
ductus venosus
b. Arteries of umbilical cord are blue since take blood back to
mother
heart
c. Vein of umbilical is red taking oxygenated blood away from
mom to
baby
2. Circulation
a. No pulmonary oxygenation (lungs collapsed)
b. Foramen ovale (between atrium)
c. Ductus arteriosus – between pulmonary & aorta
3. Birth
a. Breath = lungs fill and vessels expand
b. Smooth muscles ductus arteriosus contract
c. Pulmonary circulation begins
I. Aging System – gradual decline
1. Decreased hematocrit
2. Constriction or blockage of vessels
3. Pooling of blood
4. Inelastic walls
5. Reduction cardiac output
6. Reduction elasticity
7. Scar tissue
8. Changes in nodal & conducting cells
IV. Shock
A. Circulatory Failure- failure of vascular system to supply the tissues with
adequate blood supply; progresses if not treated
B. Types
1. Hypovolemic
a. Loss of fluid (blood, plasma, extracellular)
b. Stages
1) Non-progressive
2) Progressive
3) Irreversible
c. Compensatory mechanisms
1) Sympathetic
2) Fluid conservation
3) Hormone ADH stimulation
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4) Vasoconstriction vessels & non-essential
5) Decrease cellular energy production
a) Failure Na/K pump
b) Cellular swelling
2. Obstructive – mechanical obstruction
a. Pump, vessel
b. R heart failure, decrease venous return
3. Distributive – vascular tone, vascular enlargement
a. Vasomotor
b. Presence of vasodilator
c. States
1) Neurogenic – decreased sympathetic control
(transitory)
a) Spinal cord or brain injury, drugs,
anesthesia, hypoxia, lack of glucose
b) Spinal shock
2) Anaphylactic – allergic
a) Histamine release
b) Vasodilatation arterioles & venules
c) Capillary permeability
d) Respiratory
e) Sudden
f) Agent induced
3) Sepsis & Septic – vasodilatory
a) Severe infection & release mediators
b) Frequently Gram – negative
c) Pulmonary insufficiency
d) Disseminated intravascular coagulation (DIC)
e) Multiple organ dysfunction syndrome (MODS)
f) Micro- embolism
g) Capillary permeability/protein leakage
h) Reactive C protein
d. Complication
1) Acute Respiratory Distress Syndrome
2) Acute Renal Failure
3) Gastrointestinal
4) DIC
5) MODS)
IV. Taser Gun and cardiovascular system
A. History of Taser Gun
1. Weapon
2. Mechanism of action & effects
a. Muscle
b. Thermal injury
c. Electrical injury to tissues
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3. Demographics
B. Taser Injuries
1. Burns
2. Cardiovascular
3. Neurologic & psychiatric
4. Motor & Sensory
C. Triage and treatment