Approach to the adult patient with anemia- Lecture 2 Flashcards
(103 cards)
1
Q
What are the 4 steps in the process of erythropoiesis
A
- low O2 delivery
- EPO stimulation
- RBC proliferation and maturation
- Reticulocyte release
2
Q
What is flow of an RBC formation
A
3
Q
EPO binds to _______. What does it induce?
A
marrow erythroid precursors
induces cell maturation
4
Q
What are marrow erythroid precursors called?
A
proerythroblasts
5
Q
____ and _____ are needed to assist with proliferation of RBC
A
folate and Vit B12
6
Q
_____ assists in the accumulation of hemoglobin
A
iron
7
Q
what is the role of iron?
A
binds oxygen to hgb
8
Q
Describe the process of erythropoiesis. What do all the stars mean?
A
9
Q
Name two differentiating factors of reticulocytes as compared to RBC
A
NOT biconcave (more round)
slightly bluer than RBC
10
Q
T/F: Reticulocytes contain RNA and RBC do not
A
true
11
Q
What is the total life span of a reticulocyte?
A
4-5 days
3 days in bone marrow
1-2 days in blood
12
Q
What are the optimal conditions for erythropoiesis?
A
normal EPO production
Normal erythroid marrow function
Adequate Hgb accumulation
13
Q
What is the end result if any of the physiological processes become defective during erythropoiesis?
A
decreased RBC production
14
Q
_____ is considered a reduction of one or more of the major red blood cell measurements, what are they?
A
anemia
Hgb
Hct
RBC
15
Q
What kind of approach includes addresses the mechanism responsible for the fall in hemoglobin concentration
A
Kinetic approach to anemia
16
Q
What kind of approach includes categorizes anemias based on alterations in RBC characteristics and the reticulocyte response?
A
Morphologic approach to anemia
17
Q
The kinetic approach address the _____ responsible for the fall in hemoglobin concentration
A
mechanism
18
Q
Morphologic approach: categorizes anemias based on alterations in ______ and the _______
A
RBC characteristics
reticulocyte response
19
Q
the kinetic approach to anemia can be caused by one or more of these things, name them.
A
decreased RBC production (erythropoiesis)
increased RBC destruction (hemolysis)
blood loss
20
Q
T/F: Under steady state conditions, there is more RBC being produced than RBC being destroyed
A
FALSE, production = destruction
21
Q
on average, what is the daily production of RBC?
A
1% of red cell mass
22
Q
What are the 5 common causes for decreased RBC production
A
- Lack of nutrients (iron, B12, folate)
- bone marrow disorders
- bone marrow suppression
- low levels of trophic hormones
- acute/chronic inflammation
23
Q
What are the 3 reasons for increased RBC destruction
A
- inherited hemolytic anemias
- acquired hemolytic anemias
- hypersplenism
24
Q
What is the most common cause of anemia?
A
blood loss
25
What are the 4 types of blood loss?
1. gross blood loss
2. occult blood loss
3. iatrogenic blood loss
4. under appreciated menstrual blood loss
26
If you damage your bone marrow, what happens to the reticulocyte count?
retic count decreases
27
what happens to the retic count when you have blood loss?
retic count increases
28
what happens to the retic count when you have increased RBC destruction?
retic count increases
29
the morphologic approach classifies anemias based on ????
red cell indices (MCV, MCH, MCHC)
30
reticulocytosis will (increase/decrease) MCV
increase
31
What are some causes of macrocytic anemia?
-folate and B12 deficiency
-drugs that interfere with nucleic acid synthesis
-abnormal RBC maturation
-alcohol abuse
-liver disease results in lipid deposits on RBC increasing surface area
32
microcytic anemia is often associated with low MCHC due to ____ hgb content in the small RBC
low/decreased
33
What is most common cause of microcytic anemia?
iron deficiency**
alpha or beta thalassemia minor
34
How is normocytic anemia diagnosed?
with a peripheral smear
35
What are causes of normocytic anemia?
Chronic kidney disease
anemia of chronic disease/inflammation
mild iatrogenic hospital anemia
36
Name some causes of mild iatrogenic hospital anemia
recurrent venipuncture, blood loss from surgery, hemodilution with IV fluids, blunted erythropoiesis due to acute illness
37
Physiology of anemic symptoms is directly related to ????
decreased oxygen delivery to tissues
38
acute, moderate-severe blood loss will also cause _____ and a more severe clinical presentation of anemia
hypovolemia
39
How does the body compensate for anemia?
increase in oxygen extraction
increase in stroke volume and heart rate
40
symptoms occurring at rest indicate a ______ or the heart’s inability to compensate
lower Hbg and Hct
41
What are the common s/s associated with an anemic patient
varying degrees of fatigue
unusual exertional tachycardia/dyspnea
tachycardia/dyspnea at rest
palpitations
audible pulsations
bounding pulses
pallor
42
Name some signs of anemia complicated by volume depletion
easy fatigability
muscle cramps
dizziness/syncope
lethargy
progressive hypotension/shock/death
43
What are the 4 major questions you should ask yourself when considering a anemia patient.
-Is the patient bleeding (past or present)? If so where?
-Is there evidence of increased RBC destruction (intravascular or extravascular)?
-Is there bone marrow suppression? If so why?
-Is the patient nutrient deficient in iron, folate or B12? If so why?
44
Name some constitutional symptoms.
unintentional weight loss, loss of appetite, fever, night sweats
45
symptoms of hx of medical condition associated with anemia
Melena - Upper GI bleed, bleeding ulcer
Large hematochezia - Lower acute GI bleed
Menorrhagia - Dysfunctional uterine bleeding
Renal failure
Rheumatoid arthritis
CHF¹
46
Name some social hxs approach that points to anemia
alcohol, asa, nsaids, blood thinners
47
Describe the skin of an anemic pt
pallor, jaundice, petechiae, bruising
48
describe the eyes of an anemic pt
pale conjunctiva, scleral icterus
49
Name some additional physical exam findings commonly found in anemic patients
lymph nodes
Hepatosplenomegaly (HSM)
bony tenderness (sternum, anterior tibia)
stool for occult blood
50
Consider looking at this flow sheet, maybe?
51
Hgb, hct and RBC count are all concentrations and dependent on _____
red cell mass
52
If RCM is decreased and/or plasma volume is increased, what are the RBC and H&H doing?
RBC and Hgb and Hct will be low
53
If plasma volume is decreased, what are RBC and H&H doing?
RBC and H&H will be elevated
54
How is retic count reported?
reported as a percentage of RBC
55
Why might the retic count be a problem when evaluating an anemic patient?
fewer RBC which may falsely increase the retic count
56
What is the most accurate way to count reticulocytes in an anemic patient?
retic index calculation
57
How do you calculate Reticulocyte Index Calculation (RI)? What is normal?
RI= retic percentage x (patient's HCT/normal HCT)
RI is <3%
58
Consider maybe looking at this again?
59
Increased retic count is indicative of ______
hemolysis
60
Name 3 labs that can help you further evaluate hemolysis?
serum lactate dehydrogenase (LDH)
indirect bilirubin
serum haptoglobin
61
Destruction of the RBC will (increase/decrease) LDH
increase
62
How is indirect bilirubin calculated?
Indirect bilirubin (unconjugated= total bilirubin - direct bilirubin (conjugated)
63
bilirubin is the orange-yellow pigment derived from ???
the breakdown of hgb
64
______ binds free hgb that is released from hemolyzed RBC
Haptoglobin
65
What is the coombs test test for?
Assesses the presence of antibodies on the surface of RBC’s, which ultimately causes RBC destruction
66
What does a positive coombs test indicate?
autoimmune hemolytic anemia, hemolytic transfusion reaction, drug sensitizations, hemolytic disease of the newborn
67
Is a normal coombs test positive or negative?
negative
68
Name some lab tests associated with microcytic anemia
69
Maybe consider looking at this one again??
70
name 3 ways the human body can lose iron
perspiration
epithelial cell desquamation
menstruation
71
Where is 65% of iron in the body found?
bound up in hemoglobin molecules in RBCs
72
Where is 30% of the iron in the body stored?
stored as ferritin or hemosiderin in the spleen, bone marrow and the liver
73
Where is 4% of the iron in the body found?
bound up in myoglobin molecules
74
Where is < 1% of iron in the body found?
throughout the cells in the body
75
Where is < .1% of the iron in the body is found?
bound to transferrin (taxicab for iron)
76
What does the serum iron measure?
Measures the amount of circulating iron bound to transferrin
77
What does decreased serum iron levels indicate?
iron-deficiency anemia, nephrosis¹, anemia of chronic disease and infection, chronic blood loss, malabsorption disorders
78
What does increased serum iron levels indicate?
hemochromatosis², excessive iron intake, hemolysis of erythrocytes, liver necrosis³
79
_____ is the major plasma transport protein for iron largely synthesized by the liver
Transferrin
80
Transferrin carries iron from the _______ to ______
duodenum to the marrow
81
What does transferrin saturation calculate?
Calculates how much of the transferrin is being bound by iron
82
What does a decreased transferrin saturation indicate?
iron-deficiency anemia
83
What does an increased transferrin saturation indicate?
hemochromatosis, iron overload, thalassemia, RBC transfusions
84
What does the total iron binding capacity measure?
Measures the blood’s capacity to bind iron with transferrin; indirectly measures transferrin
85
What is the opposite of transferrin saturation?
total iron binding capacity
86
______ is the body's major iron storage protein
ferritin
87
iron molecules not transported to marrow by _____ are bound to _____ for later use
transferrin
ferritin
88
______ the most reliable indicator of total-body iron status. What is the MOST ACCURATE?
ferritin
bone marrow biospy
89
______ is more specific and sensitive than iron concentration or TIBC for diagnosing iron-deficiency anemia
ferritin
90
What things do you need to determine macrocytic anemia?
retic count
B12
folate
91
Maybe look at this again idk???
92
Vitamin B12 requires ______ and ______.
Requires intrinsic factor (produced in the stomach) for absorption in the ileum
93
in order for vitamin b12 to be absorbed normally, what things must be working?
requires a normally functioning stomach, exocrine pancreas, and intestinal mucosa
94
Where is the majority of vit B12 stored?
stored in the liver
95
folic acid requires normal functioning of ______ for absorption
intestinal mucosa
96
Where specifically is folic acid absorbed? Where is it stored?
Absorbed in the upper ⅓ of the intestine and stored in the liver
97
What do elevated serum folate levels indicate?
B12 deficiency
98
Name a responsibility of B12
move folate into tissue cells
99
Maybe consider looking at this again?? who knows?
100
What is the main cause of microcytic anemia?
iron deficiency
101
What does transferrin saturation measure?
how much transferrin is bound to iron
102
What is the pathophysiology behind an anemic patient presenting with jaundice?
hemolysis
103
What is the significance of the RDW?
acute or chronic
