RBC and bleeding disorders - SRS

Question 1

What is the unique ability of hemoglobin?

Answer 1

Bind O2 in high pO2 environment and releases O2 in low pO2 setting.

Question 2

What regulates RBC progenitor cells?

Answer 2

EPO - a glycoprotein produced and released by peritubular capillary lining cells.

Question 3

What regulates EPO?

Answer 3

pO2 - amount of oxygen available to the kidney

Question 4

When Hb levels fall below a certain level the plasma EPO levels increase logarithmically in inverse proportion to the severity of the anemia.

At what level does this occur?

Answer 4

Below 10 grams/dL

Question 5

What does RDW stand for?

Answer 5

Red cell distribution width

Question 6

What does hematocrit measure?

Answer 6

Red cell mass expressed as a % of whole blood volume

Question 7

What is the standard US measurement of anemia?

Answer 7

Hematocrit

Question 8

What is the european standard for anemia measurement?

Answer 8

Hemoglobin

Question 9

What is the normal relationship between hematocrit and hemoglobin?

Answer 9

3

Divide hematocrit by 3 to get hemoglobin

multiply hemoglobin by 3 to get hematocrit

Question 10

What does the RDW provide useful insight for?

Answer 10

Degree of anisocytosis

Question 11

What are two quick anatomical checks you can make to identify anemia?

Answer 11

Palmar crease

Conjunctiva

Question 12

What is anemia?

Answer 12

A laboratory finding clinically defined quantitatively as a patient value for hemoglobin or hematocrit which is less than 2.5 percentile value of reference range.

Question 13

What factors play into the reference ranges upon which anemia is judged?

Answer 13

Age

Sex

measuring technique used by the laboratory

geographic factors including altitude

Question 14

What are the four factors that clinical findings in RBC function deficiencies are related to?

Answer 14

1. Adequate normal hemoglobin vs. impaired hemoglobin
2. Acute (rapid) vs. Chronic (slow) loss of RBCs
3. Amount or extent of RBC volume loss
4. Indirect effects of red cell destruction (iron accumulation in thalassemia or splenic infarction in sickle cell anemia)

Question 15

Whatever its cause, anemia, when sufficiently severe leads to certain clinical findings. What are some of these?

Answer 15

Pale appearance

Weakness

Malaise

Fatigue

Dyspnea on exertion

Question 16

What changes can hypoxia cause in the liver, myocardium and kidney?

Answer 16

Fatty change

Question 17

What is a possible manifestation of myocardial hypoxia?

Answer 17

Angina pectoris, particularly if complicated by pre-existing coronary artery disease.

Question 18

In the event of acute blood loss and shock, what can develop d/t renal hypoperfusion?

Answer 18

Oliguria and anuria

Question 19

What are some symptoms of CNS hypoxia?

Answer 19

headache

dimness of vision

faintness

Question 20

What are the three mechanisms behind anemia?

Answer 20

Blood loss

Increased RBC destruction

Impaired Production

Question 21

When stressed, by what factor and over what timeline does the bone marrow upregulate red cell production?

Answer 21

4-5 fold within 7 to 10 days

Question 22

Where does hematopoiesis normally occur?

Answer 22

Red marrow - medullary cavity of flat bones in adults

Question 23

Where does hematopoiesis occur in exceptional circumstances?

Answer 23

Extramedullary hematopoiesis - Liver, spleen or even lymph nodes

Question 24

What are the effects of acute blood loss mainly due to?

Answer 24

Loss of intravascular volume

Question 25

What component of blood is primarily lost in acute blood loss?

Answer 25

plasma for the most part

Question 26

In acute blood loss a patient may experience hypovolemic shock. What kind of anemia are they likely to have? What will their EPO levels be?

Answer 26

Normochromic/normocytic anemia EPO levels normal

Question 27

What happens to white blood cell count in acute blood loss? Why?

Answer 27

Increases d/t epinephrine and decreased marginalization

Question 28

What happens to platelet count in acute blood loss?

Answer 28

Increases

Question 29

In acute blood loss what is the reticulocyte count like?

Answer 29

Normal

Question 30

Adult humans will experience symptoms with a 10-15% blood volume loss in under an hour. What are some examples of these symptoms?

Answer 30

Rapid pulse Increased respirations shortness of breath - with effort especially Light headed (all due to defects in vascular volume)

Question 31

Describe the findings you might expect if a patient has lost more than 20% blood volume in less than one hour?

Answer 31

Vascular shock, postural hypotension

Question 32

What would you expect in a patient with more than 30% blood volume loss in less than one hour?

Answer 32

Profound shock with confusion, air hunger and hypotension

Question 33

How long after an acute blood loss does it take for the reticulocyte count to increase?

Answer 33

7 days

Question 34

What are some common sources of chronic blood loss? What does this lead to?

Answer 34

GI causes Gynecological causes Iron loss

Question 35

In an older male with anemia, what should you think of as a likely cause?

Answer 35

Colon cancer

Question 36

When does chronic blood loss induce anemia?

Answer 36

1. Rate of loss exceeds the regenerative capacit of the marrow 2. Iron reserves are depleted and iron deficiency anemia appears

Question 37

Chronic anemia does not decrease vascular volume blood pressure suffiently to cause acute symptoms of hypotension. Gradual physiologic accomodation of deficient red cells can occur. What is an example of this?

Answer 37

Increased levels of high energy phosphates (2,3-DPG)

Question 38

What are some examples of chronic RBC loss/deficiency?

Answer 38

Sickle cell anemia G6PD deficiency Thalassemia Blood loss from large bowel adenocarcinoma

Question 39

What are four determinants of signs/symptoms in chronic RBC loss/deficiency?

Answer 39

1. overall severity of RBC loss 2. Rate at which loss occurs 3. duration of loss 4. associated physical health and age

Question 40

In chronic blood loss, most adults are asymptomatic until hemoglobin is what level?

Answer 40

under 7

Question 41

What is going on in this patient? Why is hematocrit high?

Answer 41

Normocytic anemia Acute blood loss High hematocrit because lost more plasma than RBC's

Question 42

What is going on with the patient whom this panel is from?

Answer 42

hypochromic Microcytic anemia Chronic blood loss