haematology Flashcards
(25 cards)
Main functions of blood
Transport (O2, nutrients, hormones),
regulation (pH, temperature),
protection (immune response, clotting).
Major components of blood
Plasma (55%)
Formed elements
(RBCs, WBCs, platelets - 45%).
What is the composition of plasma?
90% water,
7% proteins (albumin, globulins, fibrinogen),
3% other solutes (electrolytes, gases, nutrients, hormones).
Role of albumin in plasma
Maintains oncotic pressure, transports hormones, fatty acids, and drugs.
What is the clinical significance of low albumin levels?
Hypoalbuminemia can cause edema due to reduced oncotic pressure, leading to fluid accumulation in tissues.
(Guyton 4th SA Ed.)
What is the normal RBC count in adults?
Males: 4.7-6.1 million/µL, Females: 4.2-5.4 million/µL.
(LPR Fundamentals 9th Ed.)
What is the lifespan of an RBC?
Approximately 120 days, after which they are broken down in the spleen and liver.
(Guyton 4th SA Ed.)
What is the structure and function of hemoglobin?
Hemoglobin is a tetrameric protein containing iron, which binds oxygen for transport.
(Guyton 4th SA Ed.)
What are the clinical signs of iron deficiency anemia?
Fatigue, pallor, brittle nails, glossitis, and pica (craving non-food items like ice, dirt).
(LPR Fundamentals 9th Ed.)
What are the types of WBCs?
Granulocytes: Neutrophils, eosinophils, basophils.
Agranulocytes: Lymphocytes, monocytes.
What is the function of neutrophils?
Phagocytosis of bacteria, first line of defense in acute infections.
(Guyton 4th SA Ed.)
What is leukocytosis and its clinical significance?
An elevated WBC count, often indicating infection, inflammation, or leukemia.
(LPR Fundamentals 9th Ed.)
What is the normal platelet count?
150,000-450,000 per µL of blood.
(Guyton 4th SA Ed.)
What are the steps of hemostasis?
1) Vasoconstriction, 2) Platelet plug formation, 3) Coagulation cascade.
(Guyton 4th SA Ed.)
What is the clinical significance of thrombocytopenia?
Increased risk of bleeding due to a low platelet count (<150,000/µL). Causes include bone marrow disorders and immune conditions.
(LPR Fundamentals 9th Ed.)
What determines blood type?
The presence of A and B antigens on RBCs and corresponding antibodies in plasma.
(Guyton 4th SA Ed.)
What is the universal donor and recipient blood type?
Universal donor: O-, Universal recipient: AB+.
(Guyton 4th SA Ed.)
What is hemolytic disease of the newborn (HDN)?
A condition caused by Rh incompatibility between mother and fetus, leading to hemolysis in the newborn.
What is anemia?
A condition with reduced RBC count or hemoglobin, leading to decreased oxygen-carrying capacity.
LPR Fundamentals 9th Ed.
What is polycythemia?
An abnormal increase in RBCs, increasing blood viscosity and risk of clotting.
Guyton 4th SA Ed.
What is sickle cell anemia and its clinical features?
A genetic disorder causing RBCs to become crescent-shaped, leading to vaso-occlusion, pain crises, and anemia.
LPR Fundamentals 9th Ed.
What is the clinical significance of an elevated ESR (erythrocyte sedimentation rate)?
High ESR indicates inflammation, infection, or autoimmune disease.
LPR Fundamentals 9th Ed.
What are the intrinsic and extrinsic pathways of coagulation?
Intrinsic: Activated by damage inside the vessel (Factor XII).
Extrinsic: Activated by tissue factor (Factor VII). Both lead to the common pathway and fibrin clot formation.
Guyton 4th SA Ed.
What is the clinical use of heparin and warfarin?
Heparin: Fast-acting anticoagulant, used in acute settings.
Warfarin: Long-term anticoagulant, monitored by INR levels.
LPR Fundamentals 9th Ed.
