Blood and Anemia

Question 1

What is the composition of blood?

Answer 1

plasma (55%):
-water (92%)
-proteins (7%)
-salts
-lipids (cholesterol)
-carbohydrates (glucose)
-gases (O2, CO2)
cells (45%):
-RBC (4.5million/mcL)
-WBC (5000-10000/mcL)
-granulocytes
-neutrophils (60-70%)
-eosinophils (1-3%)
-basophils (1%)
-monocytes (4-8%)
-lymphocytes (20-40%)
-platelets (150,000-400,000/mcL)

Question 2

What is the hematocrit?

Answer 2

volume fraction that is cells after centrifugation

Question 3

What are the sites of hematopoiesis in adults? Children? Fetus?

Answer 3

adult: calvarium, vertebrae, ribs, sternum, pelvis
child: bones
fetus: bones, liver, spleen

Question 4

What is the basic cell of the eight major hematopoietic lineages? What can this cell differentiate into?

Answer 4

stem cells
stem cells can become CLP or CMP
CLP–>T cell or B cell
CMP–>RBC, platelets, basophil, eosinophil, neutrophil, monocyte, osteoclast

Question 5

Describe the intrinsic pathway of the coagulation cascade.

Answer 5

starts with vessel damage
XII–>XIIa
XI–>XIa (via XIIa)
IX–>IXa (via XIa)
X–>Xa (via XIa)
II–>IIa (via Xa)
fibrinogen–>fibrin (via Xa)

Question 6

Describe the extrinsic pathway of the coagulation cascade.

Answer 6

starts with trauma
VII–>VIIa
X–>Xa (via VIIa)
II–>IIa (via Xa)
fibrinogen–>fibrin (via IIa)

Question 7

What makes up the common pathway of the coagulation cascade?

Answer 7

Xa

Question 8

What is the role of anticoagulants?

Answer 8

reduce the risk of blood clots which can cause stroke, pulmonary embolism or MI in patients with AF, VTE, ACS, orthopedic surgery

Question 9

What is the MOA of warfarin?

Answer 9

blocks the vitamin-K dependent processes of producing factors II, IX, VII, X
INR monitoring is essential

Question 10

Which clotting factor is prothrombin?

Answer 10

II

Question 11

What is the MOA of apixaban, rivaroxaban, and edoxaban?

Answer 11

factor Xa inhibitors

Question 12

What is the MOA of heparin?

Answer 12

binds to and activates antithrombin, inactivating factor Xa and IIa
may be used during acute DVT and MI management

Question 13

What is the MOA of enoxaparin and LMWH?

Answer 13

reduced anti-factor IIa activity relative to anti-factor Xa activity
more favourable benefit-risk ratios
better PK
less microvascular bleeding and bleeding risk compared to UFH

Question 14

What is the MOA of dabigatran?

Answer 14

direct thrombin inhibitor

Question 15

True or false: ASA is an anticoagulant

Answer 15

false
its an antiplatelet, sometimes used in combo with DOACs

Question 16

What are examples of antiplatelet drugs?

Answer 16

platelet aggregation inhibitors:
-ASA and COX-inhibitors
oral thienopyridines:
-clopidogrel, prasugrel, ticagrelor, ticlopidine
glycoprotein platelet inhibitors:
-abciximab, eptifibatide, tirofiban
protease-activated receptor-1 antagonists
-vorapaxar
miscellaneous:
-dipyridamole (nucleoside transport inhibitor and PDE3 inhibitor)
-cilostazol (PDE3 inhibitor)

Question 17

What is the function of erythrocytes?

Answer 17

transport of oxygen from lungs into peripheral tissues

Question 18

What is the structure of hemoglobin?

Answer 18

four heme groups and four globins
-adult: two alpha, two beta
-fetal: two alpha, two gamma

Question 19

What is anemia?

Answer 19

reduction of hemoglobin in the blood to below-normal levels
-<13g/dL in males
-<11.5g/dL in females

Question 20

What might anemia be associated with?

Answer 20

abnormal hemoglobin: abnormal hematopoiesis
reduced # of RBC: decreased hematopoiesis
structural abnormalities of RBC: abnormal hematopoiesis
may be a consequence of increased loss or destruction of RBC

Question 21

Which vitamins, minerals, and macronutrients could be associated with decreased hematopoiesis?

Answer 21

iron deficiency
vitamin B12 deficiency
protein deficiency

Question 22

What is a genetic disorder that can cause abnormal hematopoiesis?

Answer 22

sickle cell anemia

Question 23

What are examples of bleeding that can put a person at risk for increased loss or destruction of RBC?

Answer 23

prolonged menstrual bleeding
peptic ulcer

Question 24

What is the morphology of a normal RBC?

Answer 24

biconcave disk
7mcm

Question 25

Provide morphologies of RBC and an example with each.

Answer 25

normocytic, normochromic anemia
-dilutional anemia
microcytic, hypochromic anemia
-iron deficiency
macrocytic, normochromic anemia
-deficiency of B12 and/or folic acid
anemias associated with abnormal RBC shape:
-elliptocytosis, spherocytosis, sickle cell anemia

Question 26

Provide examples of the many different symptoms of anemia.

Answer 26

eyes: yellowing
skin: pale, cold, yellowing
respiratory: shortness of breath
muscular: weakness
intestinal: changed stool color
central: fatigue, dizziness, fainting (severe cases)
blood vessels: low bp
heart: palpitations, tachycardia, angina or MI (severe)
spleen: enlargement

Question 27

What might cause decreased hematopoiesis?

Answer 27

bone marrow failure
-aplastic anemia
-myelophthisic anemia
deficiency of nutrients:
-B12 and folic acid (megaloblastic anemia)
-protein

Question 28

What usually causes abnormal hematopoiesis?

Answer 28

genetic abnormalities
-sickle cell anemia, thalassemia

Question 29

What might cause increased loss and destruction of RBC?

Answer 29

bleeding
intrasplenic sequestration
immune hemolysis
infections (malaria)
hemolytic anemia

Question 30

Describe hemolytic anemia.

Answer 30

increased RBC destruction
intracorpuscular defects:
-structural abnormalities
-sickle cell anemia, thalassemia, hereditary spherocytosis
extracorpuscular defects:
-antibodies, infectious agents, mechanical factors

Question 31

What is the most common form of anemia?

Answer 31

iron deficiency anemia

Question 32

What is the etiology of iron deficiency anemia?

Answer 32

increased loss of iron (chronic bleeding)
inadequate iron intake or absorption
increased iron requirements:
-babies, adolescents, adult women, pregnant women

Question 33

True or false: folate is a fat-soluble vitamin

Answer 33

false
water-soluble type of vitamin B (B9)

Question 34

What are sources of folic acid?

Answer 34

green leafy vegetables
citrus
pulses

Question 35

What is the role of folate?

Answer 35

folic acid works with B12 and vitamin C in protein and DNA metabolism
formation of red and white blood cells

Question 36

What are contributors to folate deficiency?

Answer 36

diseases in which folic acid is not well absorbed
-Celiac or Crohns
excessive alcohol
overcooked fruits and veg
hemolytic anemia or kidney dialysis
medicines (phenytoin, sulfasalazine, TMP/SMX)

Question 37

True or false: WBC disorders are usually a result of abnormal function

Answer 37

false
usually a result of abnormal number

Question 38

What might cause neutrophilia?

Answer 38

increased marrow activity:
-bacterial infections
-acute inflammation
-leukemia
release from marrow pool:
-stress
-corticosteroids
-endotoxin exposure
demargination into blood:
-bacterial infections
-hypoxemia
-stress
-corticosteroids
-exercise

Question 39

What might cause neutropenia?

Answer 39

decreased marrow activity:
-drugs
-radiation
-megaloblastic anemia
-aplastic anemia
-marrow replacement by tumor
decreased neutrophil survival
-sepsis
-viral or rickettsial infection
-immune destruction via drug
-immune destruction via antibodies

Question 40

What might cause lymphopenia?

Answer 40

immunodeficiency (AIDS
corticosteroids
toxic drugs
Cushings

Question 41

What might cause lymphocytosis?

Answer 41

medium to large, atypical lymphocytes predominant:
-viral infections
-active immune response
-lymphoma, leukemia
small, mature lymphocytes predominant:
-chronic infections (TB)
-autoimmune diseases (myasthenia gravis)
-metabolic diseases (Addisons disease)
-lymphoma, leukemia
immature cells predominant:
-leukemia, lymphoma