|
Top
Top |
| About Blood |
 |
 |
|
 |
In 1900 dr. Karl Landsteiner discovered that there were three main human blood groups which became known as A, B and O
|
|
The St. John ambulance Brigade in Ireland set up an 'on call' blood donor panel to serve hospitals in the Dublin area
|
|
In 1936 the first 'Blood bank' was opened in Cook County Hospital, Chigago - home of the Drama series 'ER'
|
|
Before World War II, when a patient required a transfusion, donors had to go to the hospital where the patient was so that they could be directly transfused. These donors were known as 'donors on the hoof'
|
|
In 1948 the Minister for Health established the National Blood Transfusion Association in Ireland
|
|
The Blood Transfusion Service Board came into existence in 1965 |
|
|
The
Origins of Blood
Blood is produced
in the bone marrow, a jellylike substance
inside the bones. In adults, the spine,
ribs, and pelvis are the primary bones
that make blood.
As the blood cells develop from the
stem cells in the marrow, they seep
into the blood that passes through the
bones and on into the bloodstream.
The different blood cells have different
life spans — red blood cells last
about 120 days in the bloodstream; platelets
about 10 days; and the various kinds
of white blood cells can last from days
to years.
The body has feedback systems that tell
it when to make new blood cells. For
example, if bodily oxygen levels are
low, the kidneys produce a hormone called
erythropoietin, which stimulates the
stem cells in the marrow to produce
more red blood cells.
|
How
Blood Travels
Blood moves in two large, continuous circles
through a network of blood vessels. The
'right circuit' moves blood from the right
side of the heart through the lungs back
to the heart (left side). The 'left circuit'
moves blood from the heart to the rest
of the body and then back to the heart.
There are different types of blood vessels:
arteries, capillaries, and veins.
Arteries carry blood away from the heart.
They branch out into smaller arteries,
which connect to capillaries. The capillaries
are very narrow — only one cell
wide. Inside the capillaries, the red
blood cells release oxygen, which passes
through the thin capillary walls and into
the surrounding tissue. The tissue releases
waste products, like carbon dioxide, which
passes through the thin capillary walls
into the blood.
Blood returns to the heart in the veins.
Veins contain one-way valves to keep low-pressure
blood flowing towards the heart, even
against the pull of gravity. Because the
blood in veins contains so little oxygen,
it appears bluish in comparison to the
bright red of oxygenated blood.
|
Everybody has Blood - Everybody needs Blood
This red liquid carries
oxygen and nutrients to all parts of the
body, and carries carbon dioxide and other
waste products back to the lungs, kidneys
and liver for disposal. It fights against
infection and helps heal wounds, so we
can stay healthy.
There's no substitute for blood. If people
lose blood from surgery or injury or if
their bodies can't produce enough, there
is only one place to turn -- volunteer
blood donors. |
Blood Types
Although blood is made of the same basic elements, not all blood is alike. In fact, there are 8 common red blood cell types, which are determined by the presence or absence of certain antigens. Since some antigens can trigger a patient's immune system to attack the transfused blood cells, safe therapy with blood depends on careful blood typing and cross-matching. |
|
Human blood travels 60,000 miles per day on its journey through the arteries, arterioles and capillaries and back through the venules and veins.
The most common blood group is O, accounting for about 46% of the world's population. However, in some areas other blood groups predominate, in Norway for example, type A is the most prevalent. |
|
7% of a person's body weight is made up of blood |
|
The minimum age for donating blood is eighteen |
|
The maximum age for donating blood is 65 (or 60 if you are a first time donor)
|
|
The most common blood group is O positive |
|
Rehydrate
by drinking plenty of fluids over
the next 24-48 hours |
|
The rarest blood group in India O- negative |
|
One in four people will need a blood transfusion at some point in their lives |
|
Only 5% of the population are regular blood donors |
|
A unit of blood lasts for just 35 days. |
|
An average adult has between 5.6 Lts and 6.8 Lts of blood |
|
Blood carries oxygen and nutrients to all parts of the body |
|
Blood carries carbon dioxide and other waste products back to the lungs, kidneys and liver for disposal |
|
There are about 1 billion red cells in two to three drops of blood |
| |
| One car accident victim may require up to 30 units of blood, a bleeding ulcer could require anything between 3-30 units of blood and a coronary artery bypass may use between 1-5 units of blood. |
|
|
