Hematology Flashcards
(197 cards)
What is the only indication for RBC transfusion with normal Hb?
Tissue Hypoxia
Confusion (brain)
Angina (heart)
Even if Hb or Hct are normal
How do you calculate Hct?
3x Hb
if Hb is 8
then Hct is 24
WHat if Hb is below 8?
RBC transfusion
What is the first tests you always do in any anemia?
CBC and Peripheral Smear
What is Anemia Defined as?
HCT:
<41% in men
<36% in women
or
Hb
<13.5 in men
<12 in women
Note this is anemia.. but does not warrant RBC transfusion
Microcytic MCV <80 Causes
- iron deficiency
- Thalassemia
- Sideroblastosis
- Lead poisoning (part of sideroblastosis)
- Anemia of chronic disease
Whats the next step when CBC shows microcytic anemia?
Iron studies
If iron studies are normal then you do Electorpheresis (to rule out thalassemia)
or
Bone marrow biopsy
Macrocytic Anemias >100 Causes
B12 / folate deficiency Alcohol Liver Disease Methotrexate Zidovudine / phenytoin
what is the next step after CBC shows macrocytic anemia?
Peripheral smear
IF you see hypersegmented neutrophils –> B12 deficency
If you see normal PMNs (3-5 segments) then its either alcohol liver disease methotrexate Zidovudine / phenytoin
Normocytic Anemia causes (80-100 MCV)
Hemolysis
Hemhorrage
Bone Marrow disorder
next step –> get the reticulocyte count
if retic count is low then its a bone marrow issue –> do BM biopsy
If reticulocyte count is high –> this is a sign of hemohrrage or hemolysis
Anemia symptoms
fatigue, tiredness, poor exercise tolerance.
DISEASE PROGRESSION :
dyspnea on exertion, light-headedness
systolic ejection murmur (flow murmur)
confusion, AMS
AMS (RBC transfusion!)
What does Red Cell Distribution Width tell you?
Measures Anisocytosis - the variation amongst the cells.
will help differentiate between IDA and Thalassemia
What is Coombs test for?
to differentiate Auto Immune Hemolytic Anemia vs Herditary Spherocytosis
What is Bone Marrow Biopsy useful for?
Normocytic anemia with low retic count
When you give 1 unit of RBCs how much should Hb and Hct go?
Hb - 1 point
Hct - 3 points
Hct Ranges?
For nomral young healthy people - can go as low as 20% (no lower)
For older patients with CAD - keep it above 30%
RBC appearance in IDA
in a normal RBC 1/3 of the rbc center should be pale
in IDA the RBC is microcytic and the 90% of it is pale in the center.
IDA has a very increased RDW (increased anisocytosis)
IDA in a young patient differential?
in women - heavy menstrual flow
in men - PUD
IDA in an older patient (over 50)
Do COLONOSCOPY!!
IDA in a 2 year old?
get a meckles scan!!
meckles diverticulum MCC
Pregnant woman with IDA?
caused by increased demand,
give her Iron and Folate (all pregnant women should be on iron and folate!)
what should you do for someone with IDA caused by poor oral intake or malabsorption?
you need Acid to absorb Iron. Give this patient vitamin C.. make their GI acidic.
if that doesnt work you have to to IV
IDA presentation
brittle nails
spoon shaped nails (poikilocytosis)
glossitis
pica
none of these are diagnostic. History helps - but you have to do iron studies to confirm diagnosis
IDA iron studies
Serum Iron - decreased Serum Ferritin - Decreased TIBC (transferrin)- increased RDW - increased Reticulocytes - Decreased
If Serum Ferritin is low (storage form) - then its automatically IDA
Remember Ferritin and Transferin are always opposite.
in IDA Ferritin is low! so transferin (TIBC) must be high