EXAM 2 Study Guide Mo Flashcards
In a healthy 45 years old male, red blood cells are formed in?
Vertebrae
How much of a whole blood sample is:
Plasma?
Formed elements (hematocrit)?
Plasma = 55%
Formed elements = 45% (this includes erythrocytes at 45% and the buffy coat which is leukocytes(WBC) and platelets which account for less than 1% of whole blood)
What are the 3 components that make up the Plasma portion of whole blood? (give me percents)
91.5% is H2O
7% is proteins
2% Other solutes
(ions, waste products, salts, lipids, enzymes, gas, and vitamins)
What are the 3 components that make up the Formed elements (hematocrit) portion of whole blood? (give me percents)
Erythrocytes
Leukocytes/WBC
Platelets
Total body weight of a person is what percentage blood and what percentage body fluids and tissues?
8% blood
92% body fluids and tissues
Leukocytes/WBC are part of the formed elements of whole blood. What is the breakdown of Leukocytes/WBC with percentages?
PMNs (Neutrophils) 40-70% Lymphocytes 20-40% Monocytes 2-10% Eosinophils 1-6% Basophils <1%
What is the most abundant and least abundant component of Leukocytes/WBC?
PMN (Neutrophils) are most abundant at 40-70%
Basophils are least abundant at less than 1%
Proteins make up 7% of plasma of whole blood. What is the component break down of Proteins with percentages?
albumin =55%
globulins = 38%
fibrinogen = 7%
In normal adult blood composition what is the formula for serum?
serum=plasma-clotting factors (e.g.,fibrinogen).
What components of blood is known as hematocrit - “crit”?
RBC, WBC, and platelets are known as hematocrit.
Tell me the Hematocrit difference between a normal person, anemia, and polycythemia?
anemia is less “crit” and polycythemia is more “crit” than normal blood.
Anemia = thin blood
Polycythemia = thick blood (more viscous)
Hb x 3 = ?
Hct
If someone is infant to 5 years old where does majority of their red blood cell production come from? (what bone(s))
Rib and Tibia
all bones but rib and Tibia is majority
20 year old throughout the remaining life span where does majority of the red blood cell production come from? (what bone(s))
Vertebra (then sternum then rib and hipbone)
Functions of RBC? (3 answers)
Transport of hemoglobin.
Transport of oxygen and carbon dioxide.
Acid-base buffer.
What regulates RBC production in response to hypoxemia (released from the kidneys mostly)
Erythropoietin
What two vitamins are needed to mature a RBC?
Vit B12 and folic acid
What destroys old RBCs and how?
Macrophages destroy old RBCs by phagocytosis.
Hb is excreted as?
bilirubin
iron is released as/to?
transferrin
Hypoxia is a stimulus to the kidneys to release erythropoietin from the kidneys mainly (10% from liver) which then does what?
erythropoietin stimulates red bone marrow and thus increases RBC counts. The more RBC the more oxygen that can be carried!
What are some ways hypoxia can develop and create a stimulus for the release of erythropoietin? (3 things)
decreased RBC count
decreased amount of hemoglobin
decreased availability of 02
If you are deficient in what three things it can cause anemia?
IRON
vitamin B12
folic acid
Where does the body store iron?
iron is stored in Hb (65%) and also in the liver, spleen, and bone marrow
Intracellular iron is stored in protein-iron complexes such as? (2)
ferritin and hemosiderin
Circulating iron is loosely bound to the transport protein?
transferrin-carrier protein
The life span of an erythrocyte is ?
100-120 days
“Old and senile” RBCs become rigid and fragile, and their hemoglobin begins to degenerate, they are trapped in ? (graveyard of RBC)
Spleen
Dying erythrocytes are engulfed by ?
macrophages
Heme and globin are separated and the WHAT is salvaged for reuse?
iron
Heme is degraded to a yellow pigment called ?
bilirubin
The liver secretes bilirubin into the intestines as ?
bile
The intestines metabolize bile into?
urobilinogen
This degraded pigment (heme-bilirubin-bile-urobilinogen) leaves the body in feces, in a pigment called ?
stercobilin (what makes poop brown)
what is free bilirubin’s solubility status? toxic or non toxic? transported by what?
Free bilirubin is NOT soluble in water, toxic to the CNS, and transported by albumin.
How is Free bilirubin removed?
Free bilirubin is removed from blood by the liver, conjugated with glucuronate and excreted in bile (not urine).
In the intestine, bacteria convert conjugated bilirubin to ?
urobilinogen (soluble).
What is responsible for the pink color of plasma?
Transferrin
Transferrin has how many iron binding sites?
two
30% of total iron “storage iron” is?
Ferritin
Hemosiderin, what is it?
iron-storage complex (water-soluble)
Methemoglobin means what in relation to iron form?
iron in ferric form (Fe+++)
What is the treatment for methemoglobinemia?
IV methylene blue (converts ferric to ferrous form)
Which iron form is the “GOOD” form?
Ferrous (Fe++)
“2 for us”
Does methemoglobin bind more readily to 02?
No, does not bind to 02 as readily, but has increased affinity for CN-
Because methomoglobin does not bind to 02 as readily, what does that mean for saturation?
defective 02 transport leads to low saturation.
What meds can cause methemoglobinemia? (3)
Nitrites, benzocaine*, metabolites of prilocaine
how will the fingernails of someone with methemoglobinemia look?
gray-blue discoloration
causes of cyanide poisoning? (4)
Nitroprusside (releases CN ions)
Bitter almond oil
KCN
Wild cherry syrup
S/S of cyanide poisoning?
Tachycardia, hypotension, coma , acidosis, increased venous O2, rapid death.
How do you treat cyanide poisoning?
To treat cyanide poisoning, use sodium nitrite and amyl nitrites to oxidize Hb to metHb (inducing methemoglobinemia) which binds cyanide, allowing cytochrome oxidase enzyme to go free and function.
Use thiosulfate to bind this cyanide, forming thiocynate, which is excreted by kidneys.
What is porphyria?
The porphyrias’ are conditions of defective heme synthesis that leads to the accumulation and increase excretion of heme precursors i.e. porphyrins
A similar condition to porhyria can be caused by what?
Lead
S/S of porphyria? (4)
Abdominal pain, N/V
Tachycardia, sustained hypertension
Muscular weakness
Seizures
If someone has porphyria what meds should you not give them (contraindicated) (2)
BARBITURATES
Benzo
What is the most common porphyria and what are the presenting symptoms?
Porphyria cutanea tarda
Blisters, photosensitivity
tea colored urine.
Which porphyria has the accumulated substrate ALA (aminolevulinic acid)?
Acute intermittent porphyria
“Anemia” would mean you have a decrease in what three components of blood?
decreased RBC, Crit, and Hb.
Hyper-segmented neutrophil is the hall mark of?
Megaloblastic anemia
Management of iron deficiency anemia in female and male patients?
give IRON, packed RBC
How do you treat megaloblastic anema (pernicious)?
Combination of folic acid and Vit B12 for life (never folic acid alone)
Pathogenesis of Sickle cell anemia?
Valine substitutes with glutamine in the 6th position of the Beta-hemoglobin chain (HbS).
(see slide 58, visual helps)
clinical manifestations of Sickle Cell Anemia?
sickling can lead to ischemia, thrombosis CVAs, and infections.
painful leg ulcers (vaso occlusive)
Hematuria
Necrosis of the spleen
Salmonella osteomylitis
Require vaccination against pneumococci, salmonella
Priapism
Cor pulmonale
Sickl “crisis” by decreased 02 and dehydration
Resistance to malaria (why?)
Treatment for sickle cell anemia?
Hydroxyurea (increase HbF), BMT
HbF interferes with formation of HbS
(this makes little sense to me, but it is what Mo has down)