Bleeding Disorders and Blood Types Flashcards
Thromboembolic disorders
These result from conditions that cause undesirable clotting like the roughening of vessel endothelium or slow-flowing blood
Thrombus
A clot that forms in an unbroken vessel. It can block the flow of blood to tissue if its large enough
Embolus
Thrombus that breaks away from a vessel wall. It moves through the circulatory system until it becomes stuck in a narrow blood vessel somewhere int he body
Anticoagulant drugs
These are used clinically to prevent undesirable clotting
- Aspirin, heparin and warfarin
Bleeding disorders
They arise from abnormalities that prevent normal clot formation
Thrombocytopenia
A deficiency in circulating platelets
- May result from any condition that suppresses/destroys red bone marrow
- treated with platelet transfusions
Impaired liver function
- can affect the synthesis of procoagulant clotting factors
- Shortage of vitamin K, diseases (hepatitis or cirrhosis)
Hemophilia
A group of genetic conditions that result in a deficiency of clotting factors
- X-linked recessive trait
- Managed clinically by transfusions
Disseminated intravascular coagulation
- Leads to widespread clotting and severe bleeding
- Does not occur by itself
- Complication of pregnancy, septicemia or incompatible blood transfusions
Differential WBC count
Used to detect differences in relative amounts of specific blood cell types
Prothrombin time
Measures the amount of prothrombin in the blood
Platelet counts
Evaluate the status of the hemostasis system
Antigens
Substances that trigger the body’s adaptive immune response
- Things that do not belong inside the body and cause disease
Antibodies
Proteins produced by lymphocytes that target specific antigens
- Bind to pathogens to inhibit their functions and makes it easier to destroy them through phagocytosis
Affinity maturation
- The immune system builds affinity for an antigen over time by refining the fit of the antibodies so they can bind more efficiently in the future
Autoimmune disease
When the maturation of lymphocytes to insure they don’t react to self-antigens fail
- the immune system reacts to your own tissues an an infection
Allergies
Immune hypersensitivities to otherwise non-pathogenic foreign substances
- Symptoms are caused by the overreaction of the immune response
Blood types
- humans have different blood types based on specific antigens on red blood cell membranes
- ABO and Rh antigens can cause strong transfusion reactions
Blood transfusion
ABO blood groups are based on the presence/absence of type A or type B antigens
- Type AB; Has both antigens but no antibodies
- Type O: has neither antigens but both antibodies
- Type A: has A antigen and anti-B antibodies
- Type B: Has B antigen and anti-A antibodies
Rh factor
- A group of RBC antigens that are either present (Rh+ blood) or absent (Rh- blood)
- Can be referred to as D antigen where the presence = Rh+
- Rh antibodies = Rh- only after exposure
Rh+ birth
- A Rh- mother can have a Rh+ baby only the first time
- The second birth, the mothers antibodies can cross the placenta and attack the fetus as the mother has already been exposed to Rh+ cells
- Treated by giving mother anti-Rho immunoglobulin
Tranfusion reaction
- Occurs if the antigens in the donor blood type attack the recipient’s antibodies = agglutination/hemolysis of donor cells
- O- = universal donor because no A, B or D antigens on it
- AB+ = universal recipient bcos no anti-a, b or d antibodies in the plasma
Blood typing
Involves determination of possible transfusion reactions before transfusion between donor and recipient’s blood types
Agglutinations
Agglutinations when blood typing means it is positive.
- this is because the antibodies in the plasma react to antigens added to the sample
- Agglutination in a cell block A and Rh+ means the recipient is positive for Type A bloodied the Rh factor meaning the recipient is A+
