Lecture Slides prepared by Meg Flemming Austin … 105/_ch_13_lect… · PowerPoint® Lecture Slides prepared by Meg Flemming Austin ... • Identify the differences between fetal

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PowerPoint® Lecture Slides

prepared by

Meg Flemming

Austin Community College

C H A P T E R 13

The

Cardiovascular

System: Blood

Vessels and

Circulation


Chapter 13 Learning Outcomes

• 13-1

• Distinguish among the types of blood vessels based on their

structure and function.

• 13-2

• Explain the mechanisms that regulate blood flow through blood

vessels, and discuss the mechanisms that regulate movement of

fluids between capillaries and interstitial spaces.

• 13-3

• Describe the control mechanisms that interact to regulate blood

flow and pressure in tissues, and explain how the activities of the

cardiac, vasomotor, and respiratory centers are coordinated to

control blood flow through tissues.



• 13-4

• Explain the cardiovascular system's homeostatic response to

exercising and hemorrhaging.

• 13-5

• Describe the three general functional patterns in the pulmonary and

systemic circuits.

• 13-6

• Identify the major arteries and veins of the pulmonary circuit.

• 13-7

• Identify the major arteries and veins of the systemic circuit.



• 13-8

• Identify the differences between fetal and adult circulation patterns,

and describe the changes in the patterns of blood flow that occur at

birth.

• 13-9

• Discuss the effects of aging on the cardiovascular system.

• 13-10

• Give examples of interactions between the cardiovascular system

and the other organ systems.


Vascular Pathway of Blood Flow (13-1)

• Arteries leave the heart and branch into:

• Arterioles feed parts of organs and branch into:

• Capillaries, where chemical and gaseous

exchange occurs, and which drain into:

• Venules, the smallest vessels of the venous

system, which drain into:

• Veins, which return blood to the atria of the heart


Three Layers of Vessel Walls (13-1)

1. Tunica intima (or tunica interna)

• Has endothelial lining and elastic connective tissue

2. Tunica media

• Has smooth muscle with collagen and elastic fibers

• Controls diameter of vessel

3. Tunica externa (or tunica adventitia)

• Sheath of connective tissue may anchor to other

tissues


Figure 13-1 A Comparison of a Typical Artery and a Typical Vein.

Tunica externa

Tunica media

Tunica intima

Smooth Muscle

Endothelium

Elastic fiber

Lumen of vein

Lumen of artery

Artery and vein LM x 60

Tunica externa

Tunica media

Tunica intima

Smooth muscle

Endothelium

ARTERY VEIN


Elastic Arteries (13-1)

• First type of arteries leaving the heart

• Examples are pulmonary trunk, aorta, and major

branches

• Have more elastic fibers than smooth muscle

• Absorb pressure changes readily

• Stretched during systole, relaxed during diastole

• Prevent very high pressure during systole

• Prevent very low pressure during diastole


Muscular Arteries and Arterioles (13-1)

• Muscular arteries

• Examples are external carotid arteries

• Tunica media contains high proportion of smooth

muscle, little elastic fiber

• Arterioles

• Tunica media has only 1–2 layers of smooth muscle

• Ability to change diameter controls BP and flow


Capillaries (13-1)

• Tunica interna only

• Endothelial cells with basement membrane

• Ideal for diffusion between plasma and IF

• Thin walls provide short diffusion distance

• Small diameter slows flow to increase diffusion rate

• Enormous number of capillaries provide huge surface

area for increased diffusion


Tunica externa

Endothelium

Tunica intima

Tunica externa Tunica media

Endothelium

Tunica intima

Tunica externa

Endothelium

Endothelial cells

Basement membrane

Internal elastic layer

Endothelium

Tunica intima

Tunica media

Tunica externa

Tunica externa

Tunica media

Tunica media

Endothelium

Tunica intima

Smooth muscle cells (Tunica media)

Basement membrane

Endothelium

Large Vein

Medium-Sized Vein

Venule

Capillary

Elastic Artery

Muscular Artery

Arteriole

Figure 13-2 The Structure of the Various Types of Blood Vessels.


Capillary Beds (13-1)

• An interconnected network of capillaries

• Entrance to bed is regulated by precapillary

sphincter, a band of smooth muscle

• Relaxation of sphincter allows for increased flow

• Constriction of sphincter decreases flow

• This occurs cyclically, referred to as vasomotion

• Control is local through autoregulation


Figure 13-4 The Organization of a Capillary Bed.

Collateral

arteries

Arteriole

Smooth muscle cells

Section of a precapillary sphincter

Arteriovenous

anastomosis

Precapillary sphincters

Capillaries

Venule

Vein

Small venule

Capillary bed

Capillary

beds

Arteriole

Small artery

LM x 125

This micrograph shows a number of capillary beds.

KEY

Consistent

blood flow

Variable

blood flow

Features of a typical capillary bed. Solid arrows indicate consistent blood flow; dashed arrows indicate variable or pulsating blood flow.


Alternate Routes for Blood Flow (13-1)

• Formed by anastomosis, a joining of blood

vessels

• Arteriovenous anastomosis bypasses capillary

bed, connecting arteriole to venule

• Arterial anastomosis occurs where arteries fuse

before branching into arterioles

• Ensures delivery of blood to key areas, brain, and heart


Veins (13-1)

• Collect blood from tissues and organs and return it

to the heart

• Venules are the smallest and some lack tunica media

• Medium-sized veins

• Tunica media has several smooth muscle layers

• In limbs, contain valves

• Prevent backflow of blood toward the distal ends

• Increase venous return


Veins (13-1)

• Large veins

• Thin tunica media and thick collagenous tunica externa

• Thinner walls than arteries because of low pressure


Figure 13-5 The Function of Valves in the Venous System.

Valve opens above

contracting muscle

Valve closes below

contracting muscle

Valve

closed

Valve

closed


Checkpoint (13-1)

1. List the five general classes of blood vessels.

2. A cross section of tissue shows several small,

thin-walled vessels with very little smooth muscle

tissue in the tunica media. Which type of vessels

are these?

3. What effect would relaxation of precapillary

sphincters have on blood flow through a tissue?

4. Why are valves found in veins, but not in

arteries?


Maintaining Adequate Blood Flow (13-2)

• Flow maintains adequate perfusion of tissues

• Normally, blood flow equals cardiac output (CO)

• Increased CO leads to increased flow through

capillaries

• Decreased CO leads to reduced flow

• Capillary flow influenced by pressure and

resistance

• Increased pressure increases flow

• Increased resistance decreases flow


Pressure (13-2)

• Liquids exert hydrostatic pressure in all directions

• A pressure gradient exists between high and low

pressures at different points

• Circulatory pressure, high in aorta vs. low in venae

cavae

• Arterial pressure is blood pressure

• Capillary pressure

• Venous pressure

• Flow is proportional to pressure gradients


Resistance (13-2)

• Any force that opposes movement

• Circulatory pressure must be high enough to

overcome total peripheral resistance

• Highest pressure gradient exists in arterioles due to

high peripheral resistance

• Vascular resistance

• Viscosity

• Turbulence


Vascular Resistance (13-2)

• Largest component of peripheral resistance

• Caused mostly by friction between blood and vessel

walls

• Amount of friction due to length and diameter of vessel

• Length doesn't normally change

• The longer the vessel, the higher the resistance

• Arteriolar diameter is primary source of vascular

resistance

• The smaller the diameter, the greater the resistance


Viscosity (13-2)

• Due to interactions between molecules and

suspended materials in a liquid

• Low-viscosity fluids flow at low pressures

• High-viscosity fluids flow only under high pressures

• Blood viscosity is normally stable

• Changes in plasma proteins or hematocrit can alter

viscosity and, therefore, flow


Turbulence (13-2)

• Eddies and swirls in fluid flow

• In smooth-walled vessels turbulence is low

• Slow flow near the walls, faster flow in center

• Injured or diseased vessels or heart valves show

increase in turbulence and decrease in flow

• Turbulent blood flow across valves produces the

sound of heart murmurs


Interplay of Pressure and Resistance (13-2)

• Blood pressure is maintained by hormonal and

neural mechanisms

• Adjusting diameter of arterioles to specific organs:

• Regulates peripheral resistance

• Regulates flow

• Allows for matching flow and perfusion to tissue needs


Blood Pressure (13-2)

• Arterial pressures fluctuate

• Systolic pressure (SP) is peak and occurs during

ventricular contraction

• Diastolic pressure (DP) is the minimum and occurs at

the end of ventricular relaxation

• Recorded as systolic over diastolic (e.g., 120/80

mm Hg)

• Pulse is alternating changes in pressures


Pulse Pressure (13-2)

• The difference between systolic and diastolic

pressures

• Pulse pressure = SP – DP

• Diminishes over distance, eliminated at the capillary

level

• Arterial recoil or elastic rebound occurs during diastole

• Adds additional push or squeeze on blood

• Results in fluctuation of pressures


Systolic

Pulse pressure

Blood

pressure

(mm Hg)

Diastolic

Ao

rta

Ela

sti

c

art

eri

es

Mu

sc

ula

r

art

eri

es

Art

eri

ole

s

Ca

pil

lari

es

Ve

nu

les

Me

diu

m-

siz

ed

ve

ins

La

rge

ve

ins

Ve

na

e c

ava

e

120

100

80

60

40

20

0

Figure 13-6 Pressures within the Systemic Circuit.


Capillary Pressures (13-2)

• Drops from 35 to 18 mmHg along capillary length

• Capillaries are permeable to ions, nutrients,

wastes, gases, and water

• Capillary pressures cause filtration out of

bloodstream and into tissues

• Some materials are reabsorbed into blood

• Some materials are picked up by lymphatic vessels


Four Functions of Capillary Exchange (13-2)

1. Maintains constant communication between

plasma and IF

2. Speeds distribution of nutrients, hormones, and

gases

3. Assists movement of insoluble molecules

4. Flushes bacterial toxins and other chemicals to

lymphatic tissues for immune response


Mechanisms of Capillary Exchange (13-2)

• Diffusion of solutes down concentration gradients

• Filtration down fluid pressure gradients

• Osmosis down osmotic gradient

• Water is filtered out of capillary by fluid or

hydrostatic pressures

• Water is reabsorbed into capillary due to osmotic

pressure


Capillary Exchange and Pressure Balances

(13-2)

• Capillary hydrostatic pressure (CHP) is high at

arteriolar end, low at venous end

• Tends to push water out of plasma into tissues at

arteriolar end, favoring filtration

• Blood osmotic pressure (BOP) is higher than in

interstitial fluid

• As CHP drops over length of capillary, BOP remains the

same, favoring reabsorption


3.6 L/day flows

into lymphatic

vessels

Return to

circulation

24 L/day

No net fluid

movement 20.4 L/day

35

Hg

25 mm Hg

CHP > BCOP

Fluid forced

out of capillary

CHP = BCOP

No net

movement

of fluid

BCOP > CHP

Fluid moves

into capillary

mm Hg

25 mm

Hg

25 mm

Hg

25 mm

Hg

18 mm

Reabsorption

Venule

Filtration

Arteriole

KEY

CHP (Capillary

hydrostatic pressure)

BOP (Blood

osmotic pressure)

Figure 13-7 Forces Acting Across Capillary Walls.


Venous Pressure (13-2)

• Gradient is low compared to arterial side

• Large veins provide low resistance ensuring

increase in flow despite low pressure

• When standing, blood flow must overcome gravity

• Muscular compression pushes on outside of veins

• Venous valves prevent backflow

• Respiratory pump due to thoracic pressures


Checkpoint (13-2)

5. Identify the factors that contribute to total

peripheral resistance.

6. In a healthy individual, where is blood pressure

greater: at the aorta or at the inferior vena cava?

Explain.

7. While standing in the hot sun, Sally begins to feel

light-headed and then faints. Explain what

happened.


Homeostatic Regulation of Perfusion (13-3)

• Affected by:

• Cardiac output, peripheral resistance, and blood

pressure

• Regulated to ensure blood flow changes occur at:

• Appropriate time, in right location, and without negative

effect on pressure and flow to vital organs

• Accomplished through:

• Autoregulation, neural and hormonal input


Autoregulation of Perfusion (13-3)

• Immediate and localized changes in:

• Vasoconstrictors, factors that stimulate

constriction

• Vasodilators, factors that promote dilation

• Tissue temperature, low O2 or pH, high CO2 cause:

• Capillary sphincter dilation causing:

• Peripheral resistance decrease causing:

• Increase in flow through capillary beds


Neural Control of Blood Pressure and Perfusion

(13-3)

• Triggered by changes in arterial pressure or blood

gas levels

• Cardiovascular (CV) centers in medulla oblongata

• Adjust cardiac output

• Vasomotor center in medulla oblongata

• Controls diameter of arterioles and peripheral resistance

• Controls venoconstriction


Figure 13-9 Short-Term and Long-Term Cardiovascular Responses.

Autoregulation

HOMEOSTASIS DISTURBED

• Physical stress (trauma,

high temperature)

• Chemical changes

(decreased O2 or pH,

increased CO2 or

prostaglandins)

• Increased tissue activity. Inadequate

local blood

pressure and

blood flow

Local decrease

in resistance

and increase in

blood flow HOMEOSTASIS

RESTORED

HOMEOSTASIS

If autoregulation is ineffective

Normal

blood pressure

and volume

HOMEOSTASIS

RESTORED

Neural and Hormonal Mechanisms

Endocrine

response (see

Figure 13-12a)

Long-term increase

in blood volume

and blood pressure

Stimulation of

receptors sensitive

to changes in

systemic blood

pressure or

chemistry

Activation of

cardiovascular

centers in the

medulla

oblongata

Short-term elevation

of blood pressure

by sympathetic

stimulation of the

heart and peripheral

vasoconstriction

Neural

mechanisms

Endocrine mechanisms

Start


Baroreceptor Reflexes (13-3)

• Receptors monitor degree of stretch

• Aortic sinuses

• Located in pockets in walls of ascending aorta

• Aortic reflex adjusts flow through systemic circuit

• Carotid sinuses

• Very sensitive to ensure adequate flow to, and perfusion

of, brain


Figure 13-10 The Baroreceptor Reflexes of the Carotid and Aortic Sinuses.

Responses to Increased

Baroreceptor Stimulation

Baroreceptors

stimulated

Cardioinhibitory

centers stimulated

Cardioacceleratory

centers inhibited

Vasomotor center

inhibited

Decreased

cardiac

output

Vasodilation

occurs


Rising blood pressure

HOMEOSTASIS RESTORED

Blood pressure declines

Start

Start

HOMEOSTASIS

Normal range

of blood pressure


HOMEOSTASIS RESTORED

Falling blood pressure

Blood pressure rises

Baroreceptors

inhibited

Vasoconstricti-

on occurs

Responses to Decreased

Baroreceptor Stimulation

Vasomotor center

stimulated

Cardioacceleratory

centers stimulated

Cardioinhibitory

centers inhibited

Increased

cardiac

output


Chemoreceptor Reflexes (13-3)

• Receptors

• Sensitive to changes in carbon dioxide, oxygen, and pH

in blood and CSF

• Located in carotid and aortic bodies, medulla

oblongata

• Decrease in pH or plasma O2, increase in plasma CO2

stimulate increase in heart rate and arteriolar

constriction

• Result is increase in BP


Hormonal Control of Cardiovascular

Performance (13-3)

• Short-term

• E and NE trigger rapid increase of cardiac output and

vasoconstriction

• Long-term

• Antidiuretic hormone (ADH), angiotensin II, EPO

• Raise BP when too low

• Atrial natriuretic peptide (ANP)

• Lowers BP when too high


Antidiuretic Hormone and Cardiovascular

Regulation (13-3)

• Released from posterior pituitary in response to:

• Decrease in blood volume

• Increase in blood osmolarity

• Presence of angiotensin II

• Results in:

• Vasoconstriction

• Conserving water by kidneys, increasing blood volume


Angiotensin II and Cardiovascular Regulation

(13-3)

• When BP decreases, kidney secretes renin

• Cascade of reactions forms angiotensin II

• Angiotensin II

• Stimulates CO, arteriolar constriction

• Immediately increases BP

• Stimulates release of ADH and aldosterone

• Stimulates thirst center


Erythropoietin and Cardiovascular Regulation

(13-3)

• Released by kidney when:

• BP drops

• Plasma oxygen drops

• Stimulates:

• RBC production

• Increases blood volume


Atrial Natriuretic Peptide and Cardiovascular

Regulation (13-3)

• Released by atrial walls when BP increases

• From stretch of atrial wall due to more venous return

• Effects

• Increases sodium (and therefore water) loss by kidneys

• Reduces thirst

• Blocks release of ADH, aldosterone, E, NE

• Stimulates arteriolar dilation


Decreasing blood

pressure and

volume

Start

HOMEOSTASIS

DISTURBED

Blood pressure and volume fall

Short-term

Long-term

Sympathetic activation

and release of adrenal

hormones E and NE

Endocrine Response

of Kidneys

Renin release leads

to angiotensin II

activation

Erythropoietin (EPO)

is released

Increased cardiac output and peripheral vasoconstriction

HOMEOSTASIS

Normal blood pressure and

volume

Angiotensin II Effects

Antidiuretic hormone

released

Aldosterone secreted

Thirst stimulated

Increased red blood

cell formation

HOMEOSTASIS

RESTORED

Blood pressure and volume rise

Increased blood pressure

Increased blood volume

Factors that compen-

sate for decreased

blood pressure and

volume

Combined Short-Term

and Long-Term Effects

Figure 13-12a The Hormonal Regulation of Blood Pressure and Blood Volume.


Increasing blood

pressure and

volume

Atrial natriuretic

peptide (ANP)

released by

the heart

HOMEOSTASIS

DISTURBED

Rising blood

pressure and

volume

Factors that compensate for increased

blood pressure and volume

HOMEOSTASIS

Normal

blood pressure and volume

Responses to ANP

Increased Na+ loss in urine

Increased water loss in urine

Reduced thirst

Inhibition of ADH, aldosterone,

epinephrine, and

norepinephrine release

Peripheral vasodilation

Combined Effects

Reduced blood

volume

HOMEOSTASIS

RESTORED

Declining blood

pressure and

volume

Figure 13-12b The Hormonal Regulation of Blood Pressure and Blood Volume.


Checkpoint (13-3)

8. Describe the actions of vasodilators and

vasoconstrictors.

9. How would slightly compressing the common

carotid artery affect your heart rate?

10.What effect would vasoconstriction of the renal

artery have on systemic blood pressure and

blood volume?


Four Cardiovascular Responses to the Stress of

Exercise (13-4)

1. Extensive vasodilation

• Increased O consumption

• Causes lower peripheral resistance

• Resulting in increased flow

2. Increased venous return

• Due to skeletal muscle and respiratory "pumps"


Four Cardiovascular Responses to the Stress of

Exercise (13-4)

3. Increased cardiac output

• Frank-Starling principle due to increased venous return

• Arterial pressures are maintained

• Increased CO balances out decrease in peripheral resistance

4. Shunting of blood flow away from nonessential

organs

• Ensures adequate perfusion of heart and skeletal

muscles


Short-Term Cardiovascular Response to

Hemorrhage (13-4)

• Loss of blood causes decrease in BP

• Carotid and aortic reflexes increase cardiac output and

peripheral resistance

• Venoconstriction accesses venous reserve

• Sympathetic activation triggers arteriolar constriction

• All mechanisms function to elevate BP


Long-Term Cardiovascular Response to

Hemorrhage (13-4)

• May take several days to restore blood volume to

normal

• Fluids are accessed from interstitial space

• ADH and aldosterone promote fluid retention

• Thirst increases

• EPO triggers RBC production

• All mechanisms lead to increase in volume and BP


Checkpoint (13-4)

11. Why does blood pressure increase during

exercise?

12. Name the immediate and long-term problems

related to the cardiovascular response to

hemorrhaging.

13. Explain the role of aldosterone and ADH in

long-term restoration of blood volume.


Three Functional Patterns of the Cardiovascular

System (13-5)

1. Distribution of arteries and veins nearly identical

except near heart

2. Single vessel may undergo name changes as it

crosses anatomical boundaries

3. Anastomoses of arteries and veins reduce threat

of temporary blockage of vessel to organ


Brain

Upper limbs

Pulmonary circuit

(arteries)

Pulmonary circuit (veins)

Lungs

RA LA

Systemic circuit

(arteries)

Left ventricle Right

ventricle Systemic

circuit (veins)

Kidneys

Spleen

Liver Digestive

organs

Gonads

Lower limbs

Figure 13-13 An Overview of the Pattern of Circulation.


Checkpoint (13-5)

14. Identify the two circuits of the cardiovascular

system.

15. Identify the three general functional patterns of

the body's blood vessels.


The Pulmonary Circuit (13-6)

• Blood exits right ventricle through pulmonary

trunk

• Branches into left and right pulmonary arteries

• Enter lungs, arterial branching nearly parallels

branching of respiratory airways

• Smallest arteriole feeds capillary surrounding alveolus

• Oxygenated blood returns to left atrium through

left and right, superior and inferior pulmonary

veins


Ascending aorta

Superior vena cava

Right lung

Right pulmonary

arteries

Right pulmonary

veins

Aortic arch

Pulmonary trunk

Left lung

Left pulmonary

arteries

Left pulmonary

veins

Alveolus

Alveolar

capillary

O2

CO2 Inferior vena cava

Descending aorta

Figure 13-14 The Pulmonary Circuit.


Checkpoint (13-6)

16. Name the blood vessels that enter and exit the

lungs, and indicate the relative oxygen content of

the blood in each.

17. Trace the path of a drop of blood through the

lungs, beginning at the right ventricle and ending

at the left atrium.


The Systemic Circuit (13-7)

• Supplies oxygenated blood to all non-pulmonary

tissues

• Oxygenated blood leaves left ventricle through

aorta

• Returns deoxygenated blood to right atrium

through superior and inferior venae cavae, and

coronary sinus

• Contains about 84 percent of total blood volume


Figure 13-15 An Overview of the Major Systemic Arteries.

Vertebral

Right subclavian

Brachiocephalic trunk

Aortic arch

Ascending aorta

Celiac trunk

Brachial

Radial

Ulnar

External iliac

Palmar arches

Popliteal

Posterior tibial

Anterior tibial Fibular

Plantar arch

Right common carotid

Left common carotid

Left subclavian Axillary

Descending aorta Diaphragm Renal Superior mesenteric

Gonadal Inferior mesenteric Common iliac Internal iliac

Deep femoral

Femoral

Dorsalis pedis


The Aorta (13-7)

• Ascending aorta is first systemic vessel

• Begins at aortic semilunar valve

• Left and right coronary arteries branch off near

base of aorta

• Aortic arch curves across top of heart

• Descending aorta drops down through

mediastinum


Three Elastic Arteries of the Aortic Arch (13-7)

1. Brachiocephalic trunk

• Branches to form right common carotid artery and

right subclavian artery

2. Left common carotid

3. Left subclavian

• This is an example of non-mirror-image

arrangement

• From here on, arteries are the same on both sides of

the body

• Designation of right and left not necessary


Subclavian Arteries (13-7)

• Supply arms, chest wall, shoulders, back, and CNS

• Internal thoracic artery

• Vertebral artery

• Thyrocervical trunk

• Supply pericardium, chest, neck, shoulder, CNS

• Becomes axillary artery

• Brachial artery

• Radial and ulnar arteries

• Form anastomoses, the superficial and deep palmar arches.

• Digital artery

• Supply upper limbs


Figure 13-16 Arteries of the Chest and Upper Limb.

Thyrocervical trunk

Right subclavian

Axillary

Deep brachial

Intercostal arteries

Brachial

Radial

Ulnar

Palmar arch

Digital arteries

Right common carotid

Vertebral Left common carotid

Brachiocephalic trunk Left subclavian Aortic arch Ascending aorta Descending aorta

Heart

Internal thoracic

Descending aorta


The Carotid Arteries (13-7)

• Common carotids ascend up into the neck and

divide

• External carotid artery

• Supplies pharynx, esophagus, larynx, and face

• Internal carotid artery

• Enters skull, supplies brain and eyes


Blood Supply to the Brain (13-7)

• Two pathways

• Vertebral arteries enter skull and fuse to form one

basilar artery

• Posterior cerebral artery

• Posterior communicating artery

• Cerebral arterial circle

• Ring-shaped anastomosis encircling the infundibulum of the

pituitary


Anterior cerebral

Middle cerebral

Cerebral arterial circle

Posterior cerebral

Basilar

Internal carotid

Carotid sinus

Vertebral

Thyrocervical trunk

Subclavian Internal thoracic

Second rib

Common carotid

Brachiocephalic trunk

Branches of the

External Carotid

Superficial temporal

Maxillary

Occipital

Facial External carotid

The general circulation pattern of arteries supplying the neck and superficial structures of the head

Figure 13-18a Arteries of the Neck, Head, and Brain.


Cerebral Arterial Circle

Anterior communicating

Anterior cerebral

Posterior communicating

Basilar

Vertebral

Anterior cerebral

Internal carotid (cut)

Middle cerebral

Posterior cerebral

The arterial supply to the brain

Posterior cerebral

Figure 13-18b Arteries of the Neck, Head, and Brain.


Major Arteries of the Trunk (13-7)

• Descending aorta

• Thoracic aorta within thoracic cavity

• Abdominal aorta after passing through diaphragm

• Phrenic artery

• First branch off abdominal aorta

• Supplies diaphragm


Unpaired Arteries of Digestive Organs (13-7)

• Supply blood to all digestive organs

• Celiac trunk

• Left gastric artery

• Splenic artery

• Common hepatic artery

• Superior mesenteric artery

• Inferior mesenteric artery


Paired Major Arteries of the Trunk (13-7)

• Gonadal arteries

• Testicular in male, ovarian in female

• Adrenal arteries

• Supply adrenal glands

• Renal arteries

• Supply kidneys

• Lumbar arteries

• Supply spinal cord and abdominal wall


Iliac Arteries (13-7)

• Abdominal aorta branches to the:

• Common iliac artery

• Branches to:

• Internal iliac artery

• Supplies pelvis

• External iliac artery

• Supplies lower limbs


Figure 13-19b Major Arteries of the Trunk.

THORACIC

AORTA

Bronchial arteries

Pericardial arteries

Esophageal arteries

Mediastinal arteries

Un

pair

ed

(m

ult

iple

)

Conducting passages of respiratory tract

Pericardium

Esophagus

Mediastinal structures

Intercostal arteries (paired, segmental)

Vertebrae, spinal cord, back muscles, body wall, and skin

Superior phrenic arteries

Diaphragm

Left gastric

Stomach, adjacent portion of esophagus

Splenic Spleen, stomach, pancreas

Common hepatic

Liver, stomach, gallbladder, duodenum, pancreas

Superior mesenteric

Pancreas, small intestine, appendix, and first two-thirds of large intestine

Inferior mesenteric

Last third of large intestine (left third of transverse colon, descending colon, sigmoid colon, and rectum)

Inferior phrenic arteries

Diaphragm, inferior portion of esophagus

Adrenal arteries

Adrenal glands

Celiac trunk

ABDOMINAL

AORTA

Renal arteries

Kidneys

Gonadal arteries

Gonads (testes or ovaries)

Lumbar arteries (paired, segmental)

Vertebrae, spinal cord, and abdominal wall

Right common iliac

Pelvis and right lower limb

Left common iliac

Pelvis and left lower limb

Right external iliac

Right internal iliac

Pelvic muscles, skin, viscera of pelvis (urinary and reproductive organs), perineum, gluteal region, and medial thigh

Left internal iliac

Left external iliac

Superior gluteal

Hip muscles, hip joint

Obturator

Ilium, hip and thigh muscles, hip joint and femoral head

Internal pudendal

Lateral rotators of hip; rectum, anus, perineal muscles, external genitalia

Lateral sacral

Skin and muscles of sacrum

Un

pair

ed

(sin

gle

)

Pair

ed

A flowchart showing major arteries of the trunk


THORACIC

AORTA

Bronchial arteries

Pericardial arteries

Esophageal arteries

Mediastinal arteries

Un

pa

ire

d (

mu

ltip

le)

Conducting passages of respiratory tract

Pericardium

Esophagus

Mediastinal structures

Intercostal arteries (paired, segmental)

Vertebrae, spinal cord, back muscles, body wall, and skin

Superior phrenic arteries

Diaphragm


Pa

ire

d

Figure 13-19b Major Arteries of the Trunk. (1 of 3)


A flowchart showing major arteries of the

trunk

Left gastric

Stomach, adjacent portion of esophagus

Splenic Spleen, stomach, pancreas

Common hepatic

Liver, stomach, gallbladder, duodenum, pancreas

Superior mesenteric

Pancreas, small intestine, appendix, and first two-thirds of large intestine

Inferior mesenteric

Last third of large intestine (left third of transverse colon, descending colon, sigmoid colon, and rectum)

Inferior phrenic arteries

Diaphragm, inferior portion of esophagus

Adrenal arteries

Adrenal glands

Celiac trunk

ABDOMINAL

AORTA

Renal arteries

Kidneys

Gonadal arteries

Gonads (testes or ovaries)

Un

pair

ed

(sin

gle

)

Pair

ed

Lumbar arteries (paired, segmental)

Vertebrae, spinal cord, and abdominal wall



Right common iliac

Pelvis and right lower limb

Left common iliac

Pelvis and left lower limb

Right external iliac


Pelvic muscles, skin, viscera of pelvis (urinary and reproductive organs), perineum, gluteal region, and medial thigh

Left internal iliac

Left external iliac

Superior gluteal

Hip muscles, hip joint

Obturator

Ilium, hip

and thigh

muscles, hip

joint and

femoral head

Internal pudendal

Lateral rotators of hip; rectum, anus, perineal muscles, external genitalia

Lateral sacral

Skin and muscles of sacrum




Lower Limb Arteries (13-7)

• External iliac artery forms:

• Deep femoral artery

• Femoral artery

• Popliteal artery

• Anterior tibial, posterior tibial, and fibular arteries

• Two anastomoses connect anterior tibial

• Dorsalis pedis arteries and two branches of posterior tibial

• Dorsal arch on top of foot

• Plantar arch on bottom of foot


Figure 13-20 An Overview of the Major Systemic Veins.

Vertebral

External jugular

Subclavian Axillary

Cephalic

Basilic Brachial

Hepatic veins

Median cubital

Radial

Median antebrachial Ulnar

Palmar venous arches

Digital veins

Great saphenous

Popliteal

Small saphenous

Fibular

Plantar venous arch

Dorsal venous arch

Internal jugular

Brachiocephalic

Superior vena cava

Intercostal veins

Inferior vena cava Renal Gonadal Lumbar veins

Left and right common iliac

External iliac

Internal iliac

Femoral

Deep femoral

Posterior tibial Anterior tibial

KEY

Superficial veins

Deep veins


Systemic Veins (13-7)

• Venous network returns blood to heart

• Arteries and veins run parallel, often similar names

• Major veins in neck and limbs different than

arteries

• Arteries are located deep

• Veins usually a set of two

• One deep and the other superficial

• Aids in body temperature control


The Superior Vena Cava (13-7)

• SVC

• Receives blood from:

• Head and neck

• Upper limbs, shoulders, and chest


Venous Return from Head and Neck (13-7)

• Small veins in brain drain into dural sinuses

• Largest is superior sagittal sinus

• Internal jugular veins

• External jugular veins

• Collect blood from superficial head and neck

• Vertebral veins

• Collect blood from cervical spinal cord and posterior

skull


Figure 13-21 Major Veins of the Head and Neck.

Temporal

Maxillary

Facial

Internal jugular

Right brachiocephalic

Left brachiocephalic

Superior vena cava Internal thoracic

Right subclavian

Vertebral External jugular

Dural sinuses

Great cerebral

Superior sagittal sinus


Venous Return from the Upper Limbs and

Chest (13-7)

• Digital vein drains into venous network in palms

• Cephalic vein

• Basilic vein

• Median cubital

• Connects cephalic and basilic veins

• Site of venous blood sample tap


Venous Return from the Upper Limbs and

Chest (13-7)

• Deeper forearm veins are radial veins and ulnar

veins

• Brachial vein joins basilic vein to form:

• Axillary vein

• Subclavian vein

• Meet and merge with internal and external jugular veins

• Creates large brachiocephalic vein SVC

• Azygos vein drains chest wall SVC


Inferior Vena Cava (13-7)

• IVC

• Collects blood from organs below diaphragm


Venous Return from the Lower Limbs (13-7)

• Plantar veins on the sole of the foot

• Plantar venous arch drains into:

• Anterior tibial vein

• Posterior tibial vein

• Fibular vein

• Dorsal venous arch drains into:

• Great saphenous vein and small saphenous vein


Venous Return from the Lower Limbs (13-7)

• Behind knee small saphenous, tibial, and fibular veins

connect

• Popliteal vein

• Femoral vein

• Great saphenous and deep femoral vein join femoral vein

• External iliac vein

• Joins internal iliac vein to become common iliac vein

• IVC


Veins of the Abdominopelvic Organs (13-7)

• As IVC ascends toward heart it collects blood

from:

• Lumbar vein

• Gonadal vein

• Renal and adrenal veins

• Phrenic vein

• Hepatic vein


Figure 13-22 The Venous Drainage of the Abdomen and Chest.

SUPERIOR VENA CAVA

Mediastinal veins

Esophageal veins

Azygos

Internal thoracic

Hepatic veins

Renal veins

Gonadal veins

Lumbar veins

Common iliac

External iliac

Internal iliac

Superficial veins

Deep veins

KEY

Digital veins

Palmar venous arches

Ulnar

Basilic Median antebrachial

Radial

Cephalic

Median cubital

Adrenal veins

Phrenic veins

Basilic

INFERIOR VENA CAVA

Intercostals Brachial

Hemiazygos

Cephalic Axillary

Brachiocephalic Highest intercostal Subclavian

External jugular

Internal jugular Vertebral


Figure 13-23a A Flowchart of the Tributaries of the Superior and Inferior Venae Cavae.

Right

vertebral

Right

external

jugular

Right

internal

jugular

Collects blood

from cranium, spinal

cord, vertebrae

Left

vertebral

Left

internal

jugular

Collects blood

from cranium, face,

and neck

Left

external

jugular

Collects blood from

neck, face, salivary

glands, scalp

Right

subclavian

Right

axillary

Veins of the

right upper

limb

Right

intercostal

veins

Collect blood

from vertebrae

and body wall

Right

brachiocephalic

Left and

right internal

thoracic

veins

Collect blood

from structures

of anterior

thoracic wall

Left

brachiocephalic

Left

subclavian

Mediastinal

veins

Collect blood

from the

mediastinum

KEY

Superficial veins

Deep veins

Azygos

SUPERIOR

VENA CAVA

RIGHT

ATRIUM

Collect blood

from the

esophagus

Esophageal

veins

Hemiazygos

Left

intercostal

veins

Collect blood

from vertebrae

and body wall

Through

highest

intercostal vein

Left

axillary

Left

brachial

Collects blood from

forearm, wrist, and

hand

Collects blood from lateral surface of upper limb

Collects blood from medial surface of upper limb

Left cephalic Left basilic

Interconnected by median cubital vein and median

antebrachial network

Left

radial

Radial

side of

forearm

Left

ulnar

Ulnar

side of

forearm

Venous network

of wrist and hand

Tributaries of the superior vena cava


RIGHT

ATRIUM

INFERIOR

VENA CAVA

Hepatic veins

Gonadal veins

Lumbar veins

Collect blood from the liver

Collect blood from the gonads (testes or ovaries)

Collect blood from the spinal cord and body wall

Phrenic

veins

Adrenal

veins

Renal

veins

Collect blood from the diaphragm

Collect blood from the adrenal glands

Collect blood from the kidneys

Right

common

iliac

Left

common

iliac

Right external

iliac

Blood from

veins in right

lower limb

Collect blood from the pelvic muscles, skin, urinary and reproductive organs of pelvic cavity


Left internal iliac

Left external

iliac

Blood from

veins in left

lower limb

Superior

gluteal

veins

Internal

pudendal

veins

Obturator

veins

Lateral

sacral

veins

Tributaries of the inferior vena cava

Figure 13-23b A Flowchart of the Tributaries of the Superior and Inferior Venae Cavae.


Hepatic Portal System (13-7)

• Portal system is two capillary beds in series

connected by portal vessel

• Blood going through capillaries of digestive organs

absorbs nutrients, some wastes, some toxins

• Blood is processed by liver before entering

general circulation


Hepatic Portal System (13-7)

• Capillaries from:

• Lower large intestine inferior mesenteric vein

• Spleen, stomach, pancreas splenic vein

• Stomach, small and large intestines superior

mesenteric vein

• All three hepatic portal vein

• Blood from gastric vein and cystic vein added

• Blood enters liver capillaries hepatic vein

IVC


Figure 13-24 The Hepatic Portal System.

Inferior vena cava

Hepatic veins

Hepatic portal Cystic

Superior mesenteric

Colic veins

Ascending colon

Intestinal veins

Superior rectal veins

Small intestine

Sigmoid veins

Descending colon

Inferior mesenteric

Left colic

Splenic

Gastroepiploic veins

Spleen

Gastric veins

Aorta

Esophagus

Liver Stomach

Pancreas


Checkpoint (13-7)

18. A blockage of which branch of the aortic arch would

interfere with blood flow to the left arm?

19. Why would compression of the common carotid

arteries cause a person to lose consciousness?

20. Grace is in an automobile accident, and her celiac

trunk is ruptured. Which organs will be affected

most directly by this injury?

21. Describe the general distribution of major arteries

and veins in the neck and limbs. What functional

advantage does this distribution provide?


Fetal Circulation (13-8)

• Biggest difference is sources of respiratory and

nutritional support

• All nutrients and blood gases supplied from

mother through diffusion across placenta

• Placenta is unique part of uterine wall

• Maternal and fetal circulatory systems in close contact


Placental Blood Supply (13-8)

• Low O2 fetal blood flows through umbilical

arteries

• At placenta:

• CO2 and wastes cross to mother

• O2 diffuses into fetal blood

• Returns to fetal circulation through umbilical vein

• Some blood goes to liver

• Rest goes to IVC through ductus venosus


Fetal Circulation in the Heart and Great Vessels

(13-8)

• Foramen ovale

• An interatrial opening

• Flap that acts as one-way valve from right to left atrium

• Allows blood to bypass pulmonary circuit

• Ductus arteriosus

• Short vessel that takes most of blood from right ventricle

directly to aortic arch of systemic circuit


Foramen ovale (open)

Ductus arteriosus (open)

Pulmonary trunk

Aorta

Placenta

Umbilical vein

Umbilical cord

Liver Inferior vena cava

Ductus venosus

Umbilical arteries

Blood flow to and from the

placenta in full-term fetus (before

birth)

Figure 13-25a Fetal Circulation.


Blood flow through the heart of a

newborn baby after delivery

Inferior vena cava

Ductus arteriosus (closed)

Pulmonary trunk

Left atrium

Foramen ovale (closed)

Right atrium

Left ventricle

Right ventricle

Figure 13-25b Fetal Circulation.


Circulatory Changes at Birth (13-8)

• Infant takes first breath

• Pulmonary vessels expand

• Ductus arteriosus contracts

• Blood flows into pulmonary trunk

• Remnants convert to ligamentum arteriosum

• Flap across foramen ovale closes

• Residual indentation is the fossa ovalis


Checkpoint (13-8)

22. Name the umbilical vessels that constitute the

placental blood supply.

23. A blood sample taken from the umbilical cord

contains high levels of oxygen and nutrients, and

low levels of carbon dioxide and waste products. Is

this sample from an umbilical artery or from the

umbilical vein? Explain.

24. Name the structures that are vital to fetal circulation

but cease to function at birth. What becomes of

each of these structures?


Effects of Aging on Blood (13-9)

• Lower hematocrit

• Formation of a thrombus, or stationary blood clot

• Can detach becoming an embolism

• Pooling of blood in veins of leg

• Due to ineffective venous valves


Effects of Aging on the Heart (13-9)

• Reduction in maximum cardiac output

• Changes in nodal and conducting cells

• Reduction of elasticity of cardiac skeleton

• Progressive atherosclerosis

• Serious if found in coronary circulation

• Replacement of damaged cardiac muscle with

scar tissue


Effects of Aging on the Vessels (13-9)

• Arteriosclerosis or thickening and toughening of

wall

• Inelastic walls of arteries less tolerant of pressure

increase

• Can lead to local dilation, an aneurysm

• Calcium salts deposited on walls

• Can lead to stroke or myocardial infarction

• Thrombi can form at atherosclerotic plaques


Checkpoint (13-9)

25. Identify components of the cardiovascular

system that are affected by age.

26. Define thrombus.

27. Define aneurysm.


Cardiovascular System Linked to All Other

Systems (13-10)

• Cardiovascular system supplies all others with:

• Oxygen

• Hormones

• Nutrients

• White blood cells

• Removes:

• Carbon dioxide and metabolic wastes


Figure 13-26

SYSTEM INTEGRATOR

Stimulation of mast cells produces

localized changes in blood flow and

capillary permeability

Provides calcium needed for normal cardiac muscle

contraction; protects blood cells developing in red

bone marrow

Skeletal muscle contractions assist in moving blood

through veins; protects superficial blood vessels,

especially in neck and limbs

Controls patterns of circulation in peripheral

tissues; modifies heart rate and regulates blood

pressure; releases ADH

Erythropoietin (EPO) regulates production of RBCs; several hormones elevate blood pressure; epinephrine stimulates cardiac muscle, elevating heart rate and contractile force

The section on vessel distribution demonstrated the extent of the anatomical connections between the cardiovascular system and other organ systems. This figure summa- rizes some of the physiological relationships involved. The most extensive communication occurs between the cardiovascular and lymphatic systems. Not only are the two systems physically interconnected, but cells of the lymphatic system also move from one part of the body to another within the vessels of the cardiovascular system. We examine the lymphatic system in detail, including its role in the immune response, in the next chapter.

The CARDIOVASCULAR

System

In

te

gu

-

me

nta

ry

Sk

ele

ta

l

Mu

sc

ula

r

Ne

rvo

us

En

do

cr-

in

e

Cardiovascular System Body System Cardiovascular System Body System

Delivers immune system cells to injury sites; clotting response seals breaks in skin surface; carries away toxins from sites of infection; provides heat

Transports calcium and phosphate for bone deposition; delivers EPO to red bone marrow, parathyroid hormone, and calcitonin to osteoblasts and osteoclasts

Delivers oxygen and nutrients, removes carbon

dioxide, lactic acid, and heat during skeletal

muscle activity

Endothelial cells maintain blood–brain barrier;

helps generate CSF

Distributes hormones throughout the body; heart

secretes ANP

In

te

gu

-

Me

nta

ry

(P

ag

e 1

38)

Sk

ele

ta

l

(Pag

e 1

88)

Mu

sc

ula

r

(Pag

e 2

41)

Ne

rvo

us

(P

ag

e 3

02)

En

do

cr-

In

e

(Pag

e 3

76)

Re

sp

ira

-

to

ry

(Pag

e 5

32)

Lym

ph

-

atic

(Pa

ge 5

00)

Dig

es-

tive

(Pag

e 5

72)

Urin

ary

(Pag

e 6

37)

Re

pro

du

-

ctive

(Pag

e 6

71)


Checkpoint (13-10)

28. Describe what the cardiovascular system

provides for all other body systems.

29. What is the relationship between the skeletal

system and the cardiovascular system?

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Lecture Slides prepared by Meg Flemming Austin … 105/_ch_13_lect… · PowerPoint® Lecture Slides prepared by Meg Flemming Austin ... • Identify the differences between fetal