10.08.18 Approach to Anemia

Question 1

an automated test to give us information about red cells

Answer 1

Complete Blood Count (CBC)

Question 2

Is hemoglobin calculated or directly measured?

Answer 2

Directly measured

Question 3

Volume of red cells per total volume of blood, given as a percentage

Answer 3

Hematocrit

Question 4

Is hematocrit calculated or directly measured?

Answer 4

Calculated

Question 5

Direct measurement of the number of red cells

Answer 5

RBC

Question 6

Direct measurement of red cell volume

Answer 6

MCV

Question 7

Calculated value, based on Hb and RBC

Answer 7

MCH

Question 8

Calculate value, based on Hb, MCV, and RBC

Answer 8

MCHC

Question 9

coefficient of variation of the MCV; how much “spread” there is in the MCVs of all the different red cells in the patient’s body

Answer 9

RDW

Question 10

How does the distribution of RDW look in iron deficiency

Answer 10

Widened

Question 11

a decreased hemoglobin/hematocrit below the normal range for gender and age; manifestation of disease not a final diagnosis

Answer 11

Anemia

Question 12

What does the clinical manifestation of anemia depend on?

Answer 12

1. Reduction of oxygen carrying-capacity
2. Change in whole blood volume (acute-less, chronic-more)
3. Rate of change of Hb
4. Cardiopulmonary compensation
5. Manifestation of illness that caused anemia

Question 13

What are most symptoms of acute hemorrhage related to?

Answer 13

Hypovolemia

Question 14

What are they symptoms of acute hemorrhage

Answer 14

1. Hypotension
2. Orthostatic changes
3. Syncope
4. Shock

Question 15

What are symptoms of tissue hypoxia

Answer 15

1. Fatigue
2. Shortness of breath
3. Cognitive difficulties
4. Ischemic pain

Question 16

How does the body respond to anemia with an increased cardiac output?

Answer 16

Increased heart rate

Question 17

What reflex does acute blood loss and hypovolemia trigger?

Answer 17

Vasoconstriction

Question 18

What are chronic changes associated with the body’s response to anemia?

Answer 18

1. Kidneys retain salt/water (transfusion require diuretic)
2. Increased 2,3DPG leads to right shift in O2 disassociation –> increased O2 delivery to tissues
3. Renal mesangial cells sense decreased O2 delivery and increase erythropoietin synthesis

Question 19

What are the mechanisms of anemia?

Answer 19

1. Hemorrhage
2. Hemolysis
3. Decreased RBC production

Question 20

How is anemia classified?

Answer 20

1. Erythropoietic response (reticulocyte count- hyperproliferative or hypoproliferative)
2. RBC size and Hb concentrantion (microcytic/hypochromic, macrocytic, normocytic/normochromic)

Question 21

On Wright-Giemsa staining these cells are polychromatophilic (grayish blue)

Answer 21

Reticulocyte

Question 22

Retic count x Hct/ideal Hct x 0.5

Answer 22

Reticulocyte index

Question 23

Retic (%) x RBC

Answer 23

Absolute reticulocyte count

Question 24

On supravital staining how are reticulocytes differentiated?

Answer 24

Have RNA “reticulated” remnants

Question 25

What does retic index <2% or absolute retic count <75000 suggest?

Answer 25

RBC production problem; --> hypoproliferative abnormality

Question 26

What does retic index >2% or absolute retic count >100000 suggest?

Answer 26

Good marrow response, so anemia is either hemorrhage (blood loss) or hemolysis (RBC destruction)

Question 27

Tends to reflect a problem with Hb synthesis iron deficiency, thalassemia, lead poisoning, anemia of chronic disease, and sideroblastic anemias

Answer 27

Microcytic anemia

Question 28

What lab value classifies microcytic anemia?

Answer 28

low MCV (<80)

Question 29

Megaloblastic- impairment of DNA synthesis Non-megaloblastic- variety of other causes

Answer 29

Macrocytic anemia

Question 30

What lab value classifies macrocytic anemia?

Answer 30

high MCV (>100)

Question 31

Either the marrow isn't working well, there is a mixed problem, or there is a very acute problem

Answer 31

Normocytic anemia

Question 32

What are the 2 approaches to treat anemia?

Answer 32

1. Treat the underlying cause | 2. Transfusion

Question 33

How do you decide whether to transfuse?

Answer 33

1. How symptomatic is the patient? 2. Can we reverse the underlying cause? 3. Do we have enough time to treat the underlying cause?

Question 34

What are the general indications that determine you need a blood transfusion?

Answer 34

1. Cardiovascular compromise (CHF, shock, angina) 2. Hypoproliferative anemia with no or prolonged recovery 3. Anemic patient is going to surgery now- blood loss potential