Blood for Essentials of Healthcare
-
Upload
rhshealthscience -
Category
Health & Medicine
-
view
180 -
download
2
Transcript of Blood for Essentials of Healthcare
Learning Targets
• Identify the functions of the blood.
• Discuss the components of the blood.
• Describe the process of blood formation and recycling.
• Discuss the blood clotting process (hemostasis)
Fun Facts
• Each adult has 8 to 10 pints of blood.
• A newborn has just over 6 ounces of blood.
• A single RBC can make a full circuit of the circulatory system in 30 seconds.
• There are 150 billion RBCs in one ounce of blood.
Functions of Blood
• If the circulatory system in the body’s highway system, the blood is like the commuters and travelers.
– It Transports: electrolytes, nutrients, waste.
– It Regulates: balances pH, hormones, body temperature, and concentration of water/electrolytes in the tissues.
– It Protects: mobilizes immune cells, clotting ability to heal injury.
Blood Components
• Blood has 4 major components:
– Plasma
– Erythrocytes
– Leukocytes
– Thrombocytes
Blood Plasma (55% of volume)
• This is the slightly yellow solution that carries the following important elements: – Water (92%)
– Plasma Proteins
– Nutrients (from the digestive system)
– Electrolytes (important to pH balance and exchange)
– Hormones, vitamins, enzymes
– Waste products
Plasma Proteins – Top 3
• Fibrinogen:
– This protein is needed for blood to clot.
– Produced in the liver.
• Albumin:
– This is the most abundant.
– Made in the liver.
– Creates osmotic pressure to prevent all of the water from seeping into the tissues.
• Globulin:
– Formed in the liver and lymphatic system.
– Some of this becomes Immunoglobulin.
– Some is made into Prothrombin in the liver to allow blood to clot.
Erythrocytes
• The Red Blood Cells– These have the
function of carrying oxygen via hemoglobin molecules located in the cells.
– They have no nucleus.
– These are developed in a complex process called erythropoiesis.
Erythropoiesis
• The process of making red blood cells occurs in the red bone marrow.
– All blood cells (except special lymphocytes) are born in red bone marrow.
– Stems cells called hemocytoblasts are stimulated by the hormone erythropoietin (released by the kidneys when RBC level drops)
– Requires B12, copper, folic acid, cobalt and iron to complete process.
The RBC Lifecycle
• RBC are usable in the body for about 120 days.
– After this time, they become worn out.
– RBCs are recycled in the spleen and liver.
– The cell parts are waste, but most of the iron is saved for reuse.
– Some iron that is not saved is eliminated in bilirubin via the digestive tract.
Hemoglobin
• As discusses, is the special molecule that carrier oxygen in RBCs.
– It is a protein.
– 1 RBC has several million hemoglobins.
• Hemoglobin functions by binding oxygen to iron (forming iron oxide which is red).
Leukocytes
• White Blood Cells have two major types:
– Granulocytes – made in red bone marrow
– Agranulocyte – made in lymphatic tissue
• These cells are part of the immune system.
Agranulocyte
• This applies to about 35% of all WBCs. These cells have solid (nongrainy) middles when examined under a microscope. – There are two types:
Lymphocytes and Macrophages (monocyte)
– The function as part of the specific immune response.
– These are made in the lymphatic tissue.
Granulocytes
• These are cells formed in red bone marrow from cells called myelocytes. They have a grainy appearance.
• There are 3 types: – Neutrophils (phagocytes)
– Eosinophils (respond to allergic or parasitic issues)
– Basophils (phagocytes that also release histamines)
Thrombocytes
• These are blood platelets.
– They are fragments of cells called megakaryocytes formed in the red bone marrow.
– They are necessary to allow the process of blood clotting to occur.
Hemostasis
• This is term for the process that stops bleeding. – When a break is detected in a blood vessel, several
actions occur. • Serotonin is released to constrict the vessels. -->
• Thromboplastin (from platelets and tissues) uses calcium to act as an enzyme, deactivates anticoagulants in blood
• Prothrombin (reacts with calcium, clotting factors and thromboplastin to covert to…)
• Thrombin (acts asn an enzyme to convert Fibrinogen in plasma to Fibrin)
• Fibrin forms a net that catches together blood cells, platelets anf forms the clot.
Because…
• A clot is only a good thing to have if there is a bleed.
• Clots can cause impairment of circulation, strokes, heart attacks.
• For those reasons, we do not want clots to form spontaneously.
• The complicated process is a safeguard to prevent accidental clot formation.
Blood Types
• Blood type is an inherited trait. – It is named based on the presence of proteins on
RBC called agglutinogen. • They have labeled A and B ( O types have none)
• People with a type of agglutinogen have antibodies against there opposite. – Ex: A has anti B, O has both anti A and B, AB has none.
• Human Blood also may contain the Rh factor. – This is the + or – part of the blood type.
– People with the Rh factor can receive Rh negative blood, but not the other way around.
What Happens When We Receive the Wrong Blood Type?
• Bad things. – The Antibodies and protein in the blood that do
not match react with each other.
– This leads to clumping of cells and hemolysis (destruction of RBCs) by immune system which is responding to the foreign proteins.
– Signs of an acute reaction include fever, increased blood pressure, pain, and shortness of breath.
– These reactions can be deadly, lead to kidney failure, etc.