Lecture 1: Introduction to Hematology Flashcards
What are the 3 things involved in anemia?
Reduction in RBC count
Reduction in Hgb
Reduction in RBC mass
Define polycythemia.
Increase in the total number of RBCs.
Increase in amt of Hgb.
Increase in RBC mass.
Define anisocytosis.
Variable RBC size.
Measured by RDW (RBC Distribution Width)
Define Poikilocytosis.
Variable RBC shape.
Measured via peripheral blood smear?
Define polychromasia.
Increased reticulocyte count in peripheral blood smear.
Define hypochromia.
Central pallor that is greater than 1/3 of the RBC.
Define micro and macrocytosis.
RBC size.
How much of our body weight does whole blood make up?
7-8%
How much blood does the average male have? Female?
Male = 12 pints
Female = 9 pints
What are the 5 functions of blood?
O2 and nutrient transport
Clotting
Immune response
Waste transport
Temperature regulation
Why do males generally have more blood?
Combination of larger physical size + testosterone production induces minor RBC production in the bone marrow.
What 4 components make up whole blood?
Plasma (55%)
RBCs (45%)
WBCs & platelets (<1%)
What layer of whole blood are WBCs and platelets in?
Buffy coat, which is found in the middle of plasma and RBCs.
What is plasma derived from?
Water and salt from the large intestine.
Where are RBCs derived from?
Main site: Bone marrow
Secondary sites: liver & spleen
What is plasma mainly made of?
90% water.
10% proteins, hormones, insulin, electrolytes, and nutrients.
What are the primary functions of plasma?
Transporting RBCs, proteins, antibodies, etc.
Maintain BP
What is the primary function of an RBC?
Oxygenating tissue.
What are the two functions of Hgb?
Carrying O2 from lungs to tissues.
Carrying CO2 from tissues to lungs.
What hormone is responsible for RBC production?
EPO
Erythropoietin, produced by the kidneys.
Minor ones include testosterone and thyroid hormone.
Where are most RBCs made?
Bone marrow.
What is the lifespan of an RBC?
4 months, 120 days.
What describes the shape of a normal RBC?
Flexible, bright red biconcave disc.
What are the 5 types of WBCs?
Neutrophils (most abundant)
Lymphocyte
Monocyte
Eosinophil
Basophil
Note:
Never Let Monkeys Eat Bananas
Also keeps them in order of abundance
When do I see a left band shift? Lymphocytosis?
Left band shift = Bacterial infections.
Lymphocytosis = Viral infections.
What is unique about a platelet?
No nucleus.
It is a cell fragment.
What hormone stimulates platelet production?
Thrombopoeitin, made by the liver and kidney.
Where can I find extra platelets?
Spleen
What is the lifespan of a platelet?
7-10 days.
What is the typical differential breakdown of a diff?
50-70% neutrophils
0-5% band neutrophils
20-40% lymphocytes
2-6% monocytes
1-4% eosinophils
0-1% basophils
What factors increase Hgb?
Male
Young infants
High altitude
Smokers
What factors decrease Hgb?
Pregnancy
Female
Why does smoking increase Hgb?
Left shift in Hgb dissociation curve due to inefficient Hgb. The body produces more Hgb to compensate.
What is hematocrit?
RATIO of RBC volume to blood volume.
Hct = (RBC * MCV)/10
Hct = Hgb x3
Who has the higher range of Hct?
Males.
What is MCV?
Mean corpuscular volume, aka individual RBC size.
What describes MCV status?
Microcytosis
Normocytosis
Macrocytosis
What is MCH?
Mean Corpuscular Hemoglobin, aka Amt/weight of Hgb per RBC. (Directly related to RBC size)
What describes MCH status?
Hypochromia
Normochromia
Hyperchromia
How is MCH calculated?
MCH = (Hgb/RBC) x 10
How are anemias categorized?
MCV and MCH status, such as a normocytic hypochromic anemia.
What is MCHC?
Mean Corpuscular Hemoglobin Concentration, aka average Hgb concentration in each RBC.
It is a ratio of Hemoglobin to Hematocrit.
How is MCHC calculated?
Hgb/Hct
What is RDW?
RBC Distribution Width, aka Percentage of RBCs OUT of normal range in terms of size.
Directly related to MCV changes.
What is increased RDW known as?
Anisocytosis.
Often includes reticulocytosis.
What is the difference between thrombocytosis and thrombocythemia?
Thrombocythemia is technically primary thrombocytosis, aka idiopathic.
Overall, it just means high platelet counts.
What is MPV?
Mean platelet volume, aka average size of platelets.
When do I see increased MPV? Decreased MPV?
Increased MPV = increased platelet production bc young platelets are big.
Decreased MPV = decreased platelet production.
What is the purpose of a peripheral blood smear?
Manually assessing blood cell morphology and cell counts.
Visualizing neoplastic cells from bone marrow.
