Transcript Cardiovascular - Mounds Park Academy Blogs

Circulatory System
Blood is 8% of body weight
6 qts. for avg. sized person
3X more viscous than water
A few sayings about
Blood
• Blood cannot be washed out with blood. - Afghan proverb
• Blood alone moves the wheels of history. – Benito Mussolini
• The best blood will at some time get into a fool or a mosquito. - Austin O’
Malley
• A pint of sweat will save a gallon of blood. - George S. Patton
• “I have nothing to offer but blood, toil, tears and sweat.” – Winston Churchill
• “Humor is a rubber sword - it allows you to make a point without drawing
blood”
– Groucho Marx
“The
thorn from the bush one has planted, nourished and pruned pricks
more deeply and draws more blood.” - Maya Angelo
History of Blood
• The ancient Greeks made the first
descriptions of heart structure.
• Leonardo DaVinci and his
contemporaries made very explicit
descriptions of the heart , arteries
and veins.
• By the 1650’s people knew of
pulmonary circulation.
• William Harvey (1628) made the
first description of the process of
systemic circulation.
• By 1750 Harvey’s description was
universally accepted in the
Western world.
Functions
• Transports
nutrients
• Transports O2
• Transports
wastes
• Transports
hormones
• Protects
against disease
• Regulates
body temp.
• Regulates
fluid & salt
balance
Lymphatic system returns body fluids back to circulatory system
Lymph System
- Lymph
empties into
progressively larger lymphatic
vessels which merge into the
Thoracic Duct.
- The lymph flows into the right
and left subclavian veins in the
thorax.
- The lymphatic system is as a
low pressure drainage system
that collects a small portion of
fluid from throughout the body
and returns it to the bloodstream.
-The lymphatic system depends
on muscular movement,
breathing, and simple gravity to
move lymph fluid throughout the
body.
Blood Components
• Red Blood Cells
• Buffy coat is a
grayish layer of
White Blood Cells
and platelets
• Plasma
• Hematocrit is the %
of RBC’s in whole
blood
• Normal volume is
about 6 qts.
• Blood plasma is a clear,
slightly yellowish fluid.
• It is a water solution
containing digested food
materials as well as the
wastes from the tissues.
• Plasma carries
antibodies and
hormones.
• Plasma transports most
of the waste CO2 from
the tissues back to the
lungs
• Plasma carries salts and
proteins which help in
maintaining the correct
osmotic balance
between the blood and
the tissues.
• Blood serum = plasma protein
Blood Plasma
• There are three main
groups of plasma
proteins.
• Albumins (55%)
transport pigments,
hormones and drugs.
They help to maintain
blood volume.
• Globulins (38%) gamma work as
antibodies, alpha and
beta transport lipids
and hormones
• Fibrinogen (7%)
involved in clotting
Plasma proteins
• Biconcave disk
• Transports O2 and
some C02
• Will stack up as they
move through tiny
capillaries
3 to 5 days for a RBC
to mature, they last
for about 120 days
2.4 million prod. /sec.
Red Blood Cells
• Erythropoiesis is the
production of red blood
cells (RBC’s)
• This occurs in the red
bone marrow.
• In children, RBC’s are
produced in the marrow
of all of the bones.
• In the fetus RBC ‘s are
produced in the liver,
spleen and lymph nodes.
• The process starts with
undifferentiated cells
called stem cells.
• The nucleus is extruded
near the end of the
development of the RBC.
Erythropoiesis
Red Blood Cells cont.
• Because they are
non-nucleated they
cannot repair
themselves
• After a while they
are full of little
tears and nicks
• Old, damaged
RBC’s are
phagocytized by
the liver, spleen or
the bone marrow
• Anemia - reduced #
of RBC’s : can be
caused by diet and/or
disease
• Sickle cell anemia incomplete
dominance of normal
blood cell with
recessive sickle cell
trait.
• Heterozygous state
seems to give
resistance to malaria.
RBC abnormalities
• White Blood
Cells
(leukocytes)defend the
body against
disease.
• WBC’s have a
nuclei and
develop from
stem cells in
the red bone
marrow.
• Some mature
in other
organs.
(lymph nodes,
thymus)
• WBC’s can
leave blood
vessels
through a
process called
diapedesis.
White Blood Cells
White Blood Cells cont.
• Two main groups
are granular and
agranular
• They ingest foreign
protein, secrete
histamine, secrete
heparin, secrete
antibodies.
• This slide shows a
WBC swallowing
two yeast cells.
Granular leukocytes - Neutrophils
• 55-75% of the WBC pop.
• Form in the red bone
marrow.
• Live short lives (hrs. to 4
days)
• Numbers increase during
infections.
• Rapidly engulf foreign
elements/cellular debris.
• Strong enzymes in specific
granules and lysosomes
destroy them.
Granular - Eosinophils
• 1-3% of WBC’s
• Phagocytic in immune
responses.
• Involved in late-onset phase
of asthmatic attacks. May
cause damage by increasing
cell permeability to allergic
substances.
• Limit the expression of mast
cell degranulation during
allergic reactions.
Granular - Basophils
• 0-1% of WBC’s
• Degranulate in allergic
reactions, releasing
histamine, serotinin, and
heparin.
• This induces contraciton of
smooth muscle, increases
vascular permeability
enhancing the effects of
inflammation.
Nongranular - lymphocyte
• 20-45% of WBC’s
• Arise from the bone marrow.
• Also from lymph nodes,
spleen and thymus.
• 20% B cells, from bone
marrow, short lived, secrete
antibodies.
• 70% T cells, long-lived, from
thymus. May be cytotoxic,
helper or suppressor cells
associated with cellmediated immunity.
• Third kind is Natural killer
cells
Nongranular - Monocyte
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2-8% of WBC’s
Arise in the bone marrow.
Mature in the blood (8 hrs.)
Critical in immune response
Macrophages
Destroy antigens.
Phagocytose cellular and
related debris in wound
healing, bone formations and
other activities where
breakdown occurs.
Platelets
• Also called
thrombocytes, are not
complete cells. They are
tiny fragments of
membrane-enclosed
cytoplasm pinched off
from giant cells
(megakaryocytes) in the
bone marrow
• They last about 10 days
and they function in
blood clotting
Platelets cont.
• Function in physically
plugging leaks in blood
vessels and they also
release chemicals that
promote clotting
• Prothrombin, Ca+2, and
the platelets’ clotting
factors are involved in
making a clot.
• Codominance
between A,B
which are both
dominant over O
• Rh factor
important to
mothers who are
Rh negative and
have an Rh
positive child
• Blood type varies
with different
cultures
Blood Types
The transfusion will work if a person who is going to receive blood has a blood group
that doesn't have any antibodies against the donor blood's antigens. But if a person
who is going to receive blood has antibodies matching the donor blood's antigens, the
red blood cells in the donated blood will clump.
• The first historical attempt at blood
transfusion was described by the
15th-century chronicler Stefano
Infessura.
• Infessura relates that, in 1492, as
Pope Innocent VIII sank into a
coma, the blood of three boys was
infused, through the mouth, into the
dying pontiff.
• The boys were ten years old, and
had been promised money.
• However, not only did the pope die,
but so did the three children.
Blood Transfusion History
• The first fully-documented human
blood transfusion was administered
by Dr. Jean-Baptiste Denis,
physician to King Louis XIV of
France, on June 15, 1667.
• He transfused the blood of a sheep
into a 15-year old boy, who
recovered.
• Denis performed another
transfusion into a labourer, who
also survived.
• The small amount of blood
transfused allowed those two people
to survive those events.
• He transfused some calf’s blood
into another person who died.
• After other failures this procedure
was banned in France and other
European countries.
First Transfusions
• In 1818, Dr. James Blundell, a
British obstetrician, performed the
first successful blood transfusion
of human blood, for the treatment
of postpartum hemorrhage.
• He used the patient's husband as a
donor, and extracted four ounces
of blood from his arm to transfuse
into his wife.
• During the years 1825 and 1830,
Dr. Blundell performed 10
transfusions, five of which were
beneficial, and published his
results.
• He also invented many
instruments for the transfusion of
blood.
• Transfusions became more
common but many people still
died.
First Success
• In 1901 Austrian Karl Landsteiner
discovered human blood groups.
• Mixing blood from two individuals
can lead to blood clumping or
agglutination.
• Landsteiner discovered that blood
clumping was an immunological
reaction which occurs when the
receiver of a blood transfusion has
antibodies against the donor blood
cells.
• Karl Landsteiner's work made it
possible to determine blood groups
(A, B, AB, O) and thus paved the
way for blood transfusions to be
carried out safely.
• For this discovery he was awarded
the Nobel Prize in Physiology or
Medicine in 1930
Blood Groups
• The first transfusions had to be
made directly from donor to
receiver before coagulation.
• In 1910 it was discovered that by
adding anticoagulant and
refrigerating the blood it could be
stored for a period of days.
• This opened the way for blood
banks.
• The first non-direct transfusion
was performed on March 27, 1914
by the Belgian doctor Albert
Hustin.
• The first blood transfusion using
blood that had been stored and
cooled was performed on January
1, 1916.
Preserving Blood
• Oswald Hope Robertson, a medical
researcher and U.S. Army officer,
established the first blood bank
while serving in France during WW
I.
• The first academic institution
devoted to the science of blood
transfusion was founded by
Alexander Bogdanov in Moscow in
1925.
• Bogdanov was motivated by a
search for eternal youth and the
possibilities of bringing back the
dead.
• He believed that 11 blood
transfusions had improved his
eyesight and cured his baldness.
• He later died after receiving some
blood that was not compatible with
his.
First Blood Banks
First US Blood Banks
• In 1937 Bernard Fantus, at the
Cook County Hospital in
Chicago, established the first
hospital blood bank in the United
States.
• In creating a hospital laboratory
that preserved and stored donor
blood, Fantus originated the term
"blood bank".
• Within a few years, hospital and
community blood banks were
established across the United
States.
Plasma and RBC’s
• In the late 1930s and early
1940s, Dr. Charles R.
Drew’s discovered that
blood could be separated
into blood plasma and red
blood cells.
• The plasma could be frozen
separately.
• Blood stored in this way
lasted longer and was less
likely to become
contaminated
• Carl Walter and W.P. Murphy, Jr.,
introduced the plastic bag for blood
collection in 1950.
• Further extending the shelf life of
stored blood was an anticoagulant
preservative, CPDA-1, introduced in
1979, which increased the blood
supply and facilitated resourcesharing among blood banks
Other Discoveries
Rh Factor
• In 1939-40 Karl Landsteiner,
Alex Wiener, Philip Levine,
and R.E. Stetson discovered
the Rhesus blood group
system.
• This was found to be the
cause of the majority of
transfusion reactions up to
that time.
• Every two seconds someone in the
U.S. needs blood.
• More than 38,000 blood donations are
needed every day.
• One out of every 10 people admitted
in a hospital needs blood.
• Total blood transfusions in a given
year: 14 million (2001)
• The average red blood cell
transfusion is approximately 3 pints.
• The blood type most often requested
by hospitals is Type O.
Blood Bank
• The blood used in an
emergency is already on the
shelves before the event occurs.
• Sickle cell disease affects more
than 80,000 people in the U.S.,
98% of whom are African
American. Sickle cell patients
can require frequent blood
transfusions throughout their
lives
• More than 1 million new people
are diagnosed with cancer each
year. Many of them will need
blood, sometimes daily, during
their chemotherapy treatment.
• A single car accident victim can
require as many as 100 units of
blood.
Blood Bank cont.
Donor Eligibility
• You must be at least 17 years old, weigh more than 110 pounds, and be
in good general health to donate.
• A healthy donor may donate red blood cells every 56 days
• A healthy donor may donate platelets as few as 3 days apart, but a
maximum of 24 times a year.
• A sterile needle is used only once for
each donor and then discarded.
• Blood donation is a four-step
process: registration and medical
history, mini-physical, donation,
and refreshments.
• Every blood donor is given a miniphysical, checking the donor's
temperature, blood pressure, pulse
and hematocrit level (red blood cells
count) to ensure it is safe for him or
her to give blood
• The actual blood donation typically
takes less than 10-12 minutes. The
entire process, from the time you
arrive to the time you leave, takes
about an hour
Donating Blood
Donation facts
• The average adult has about 10
to 12 pints of blood in his body.
Roughly 1 pint is given during a
donation
• All donated blood is tested for
HIV, Hepatitis B and C, syphilis
and other infectious diseases,
before it can be released to
hospitals
• Information given to the
American Red Cross is strictly
confidential. It may not be
released without your
permission except as directed by
law
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The number of blood donations
collected in the U.S. in a year: 15
million (2001)
The number of blood donors in the
U.S. in a year: 8 million (2001)
The number of patients who receive
blood in the U.S. in a year: 4.9
million (2001)
The volume of blood transfused to
patients is increasing at the rate of
6% per year (2001)
The demand for blood transfusions
is growing faster than donations
Current Donor/Blood situation
Blood donations cont.
• Less than 38% of the U.S.
population is eligible to
donate blood
• Blood cannot be
manufactured — it can only
come from generous donors
• Shortages of all blood types
usually occur during the
summer and winter holidays
Shelf Life
• Whole blood can be processed
into red cells, platelets, plasma,
and cryoprecipitate.
• It is possible to donate specifically
only platelets or plasma. This
process is called apheresis.
• Most donated red blood cells must
be used within 42 days of
collection.
• Donated platelets must be used
within 5 days of collection.
• The body will replenish the
elements given during a blood
donation - some in a matter of
hours, and others in a matter of
weeks
• The American Red Cross
blood program started in 1940,
under the leadership of Dr.
Charles Drew.
• They supply approximately
45% of the nation's blood
supply.
• They provide blood for
patients in nearly 3,000
hospitals in the U.S.
• The Red Cross makes blood
available to any patient who
needs it — patients are not
required to find donors to
replace the blood they use.
Red Cross
American Red Cross – cont.
• 80% of the blood donations
given to the Red Cross are
collected at mobile blood
drives.
• The remaining 20% are
collected at fixed Red Cross
donor centers.
• The American Red Cross
works with over 50,000
sponsors each year to hold
more than 120,000 blood
drives, providing convenient
locations for people to give
blood
• Pumps oxygen
poor blood to
the lungs and
oxygen rich
blood to the
body.
• It is a twosided pump,
consisting of 4
chambers.
• About fistsized
• Output varies
from 5 to 35L
of
blood/minute
Heart
The pericardium
• The heart is enclosed
in a tough connective
tissue sack called the
pericardium.
• The wall of the heart
consists of the
endocardium- inner
lining
• Myocardium -thick
cardiac muscle layer
• Epicardium connective tissue outer
layer
Blood flow through the heart
• Atria (upper chambers)
receive blood from
outside the heart.
• Ventricles (lower
chambers) pump blood
out of the heart.
• Valves prevent the blood
from flowing back to
where it was.
• Left ventricle has the
thickest wall since it
pumps blood to the body
not just to the lungs.
• Rt. Atrium - Rt. Ventricle
- lungs - Lt. Atrium - Left
Ventricle - body.
Tricuspid and Bicuspid Valves
• Tricuspid valve (#3)
prevents blood in the
right ventricle from
back flowing into the
right atrium when
that ventricle
contracts
• Biscupid (mitral)
(#9) valve prevents
blood in the left
ventricle from
backflowing into the
left atrium
Coronary Arteries
• The heart
tissue is
supplied with
blood from the
relatively tiny
the coronary
arteries.
• Blockages of
these arteries
causes heart
attacks
• Angioplasty is a treatment
used to improve blood
flow through a narrowed
artery.
• It is known as P.T.C.A.
(Percutaneous
Transluminal Coronary
Angioplasty.
• A small rubber balloon is
threaded into the artery
(from the groin area) and
inflated to enlarge the
afflicted vessel.
• A metal stent is inserted to
maintain the arteries
diameter.
• Overtime a thin layer of
cells grows over the stent
preventing blood from
sticking to the stent.
Angioplasty and Stents
• Angioplasty
• Specialized heart
muscle tissue initiates
and coordinates the
heart’s rhythmic beat.
• The sinoatrial node
(the heart’s
pacemaker) initiates
the beat and starts
atrium contraction.
• The atrioventricular
node recieves
impulses from the SA
node, pauses and then
initiates ventricular
contraction.
Heart Beat
Another look at the SA and AV nodes
• heart function
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Pacemakers are devices that
“pace” the heart rate when it
is too slow (brachydia).
They can take over for the
sinoatrial node, when it is
functioning improperly.
Pacemakers monitor and
regulate the heart, they
transmit electrical impulses
to stimulate the heart if it is
beating too slowly.
The pacemaker is
implanted, underneath the
skin, just below the
collarbone, in a procedure
that takes about two hours.
It is programmed to
stimulate the heart at a predetermined rate, and settings
can be adjusted at any time.
Routine evaluation,
sometimes even via
telephone, ensures the
pacemaker is working
properly.
Battery life, generally runs
from five to ten years.
Artificial Pacemakers
Dual Pacemaker diagram
Implanted Cardioverter Defibrillators (ICDs)
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ICDs are effective in stopping
arrhythmias.
They are the most successful therapy to
treat ventricular fibrillation, the major
cause of sudden cardiac death.
ICDs monitor the heart rhythm, they
automatically function as pacemakers
for heart rates that are too slow, and
deliver life-saving shocks if a
dangerously fast heart rhythm is
detected.
(ICDs) are small devices, about the size
of a pager, that are placed below the
collarbone.
If the heart beats too quickly, the
ventricles will not have enough time to
fill with blood and will not effectively
pump blood to the rest of the body. Left
unchecked, the rapid heartbeat could
cause death.
To intervene, the ICD issues a
lifesaving jolt of electricity to restore
the heart’s normal rhythm and prevent
sudden cardiac death.
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Congestive Heart failure
occurs when the pumping
action of the heart is
impaired.
This causes an inadequate
delivery of blood (cardiac
output, CO).
Decreased CO leads to
excessive fluid
accumulation in the body.
Excessive fluid retention +
heart failure = congestive
heart failure
Congestive Heart Failure
Congestive Heart Failure cont.
• Causes: Almost anything that
causes the heart to increase its
workload for a prolonged
period or produces anatomic
damage that makes it more
difficult for the heart to
function"
• 1. Myocardial ischemia with
subsequent injury to cardiac
muscle
• 2. Toxic injury caused by
chemicals
• 3. Infection of the heart
• 4. Congential or genetic
abnormalities
X-Ray of Congestive Heart Failure
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There is a special pacemaker for
certain patients with heart failure.
In Cardiac Resynchronization
Therapy, an implanted device
paces both the left and right
ventricles (lower chambers) of the
heart simultaneously.
This resynchronizes muscle
contractions and improves the
efficiency of the weakened heart.
Devices for Heart Failure
Cardiac Resynchronization therapy
• Most of these devices can be
implanted with minor surgery
that may be done as outpatient
procedures
• Wires (leads) are placed in the
right upper and lower chambers
of the heart.
• A small computer, or
microprocessor, is implanted
under the skin, usually near the
collarbone.
• These "built-in" computers have
increased survival and the
quality of life for people with
heart failure.
Heart Transplants
• A heart transplant may be
necessary due to a cardiac
problems which ends in
deterioration of the heart
muscle.
• The two most common
cardiac problems are
coronary artery disease and
idiopathic cardiomyopathy.
(a cardiomyopathy of
unknown origin.)
• As the cardiac problem
progresses, the heart grows
weaker and increasingly less
able to pump blood.
Heart Transplants
• Eventually, the heart works
so hard to pump blood that it
may simply wear out.
• Drugs, mechanical assist
devices and other therapies
can sometimes stabilize and
even improve a patient's
condition.
• When those treatments fail,
transplantation becomes the
only therapeutic option.
• A heart-lung machine
allows the patient to
receive oxygenated blood
before the transplant is
grafted into place.
Cardiac muscle tissue
• Intercalated disks are
connection points
between cardiac
muscle cells and
allow impulses to
quickly flow from
one cell to another.
• Cardiac cells are
branched further
enhancing
connections with
other cells.
Cardiac Cycle
• There are two
basic parts, a
contraction
(systole) phase
and a relaxation
(diastole) phase.
• The lub-dub
sound of the heart
is caused by the
closure of the
heart valves
(tricuspid &
mitral, then
semilunar valves).
• Blood pressure is measuring
the pressure, or tension, that
blood exerts on the walls of
the blood vessels.
• In a healthy person, this
pressure is just enough for
the blood to reach all the
cells of the body, but not so
much that it strains blood
vessel walls.
• Generally, blood pressure
will go up at certain times.
• Normal resting blood
pressure should not go
above 140/90.
Blood Pressure
Heart Beat
• cardiac cycle
Pulmonary embolism
• pulmonary embolism
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Hearing a distinctive murmur
indicates a possibled valve
problem.
To find out what kind of valve
problem the patient has, the
doctor may order various tests,
including an echocardiogram,
an electrocardiogram, a chest
x-ray, or cardiac
catheterization.
The patient may be treated with
medications to help prevent
valve problems.
In serious situations the doctor
may recommend heart valve
surgery.
During this surgery, problem
heart valves will either be
repaired or replaced.
The top picture represents a
valve that is hard to open.
Stenosis occurs when a valve
doesn't open completely.
The bottom picture show a
valve that does not close
completely. Insufficiency (also
called regurgitation) results
when the valve doesn't close
tightly.
Heart Murmur
Echocardiogram
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An echodardiogram is a
noninvasive (the skin is not
pierced) procedure used to
assess the heart's function and
structures.
A transducer (like a
microphone) sends out
ultrasonic sound waves at a
frequency too high to be heard.
When the transducer is placed
on the chest at certain locations
and angles, the ultrasonic
sound waves move through the
skin and other body tissues to
the heart tissues, where the
waves echo off of the heart
structures.
The transducer picks up the
reflected waves and sends
them to a computer.
The computer interprets the
echoes into an image of the
heart walls and valves.
Factors that affect Heart Rate
• Nervous system
• Hormones
• Body
temperature
• Ion
concentrations
• Male or female
• Age
Heart Rate disturbances
• Tachycardia - fast
heart rate
• Brachydia - slow
heart rate
• Arrhythmia alteration in normal
rhythm
• Fibrillation uncoordinated
contraction of heart
muscle