Hematology Flashcards
(280 cards)
Most common antiseptic used for phlebotomy
70% alcohol
angle between skin and needle
15-30°
cuases of specimen hemolysis
- prolonged tourniquet application
- moisture/contamination
- too small bore needle
- excessive agitation
- frothing of blood
distance of tourniquet above the puncture site
3 to 4 inches OR 7.5 to 10 cm
usual type of EDTA used in the lab and the no. of inversions needed
action of anticoag
what’s the concentration per mL of blood
K2EDTA; 8
chelation of calcium
1.5 mg/mL
blood must be analyzed for CBC within how many hours?
if blood smear prep?
within 6 hrs of collection
within 3 hrs of collection
MPV is what?
how much does it swell when EDTA is used during the first hour?
mean platelet volume
20% increase
green top tubes contain what anticoag?
how many inversions?
what’s the anticoag concentration?
mode of action?
heparin
8
15-20 units per mL
binds antithrombin
3 types of heparin formulations
2 main tests heparin is used for
types: ammonium, sodium and lithium heparin
tests: OFT and blood gas studies
what anticoag causes cellular clumping which leads to pseudoleukocytosis and pseudothombocytopenia
heparin
light blue top anticoag?
no. of inversions?
action?
3.2% sodium citrate
3-4
chelation of Ca
factors that affect coag test (mnemonics)
in shortened? in prolonged?
Shortened: Hemolysis, Excessive agitation, Prolonged tourniquet, Excess needle manipulation, Plt contam
Prolonged: clots, inc anticoag conc.
black top ac and tests
3.8% sodium citrate for Westergren and ESR
pink top tube ac and uses
K2EDTA and blood bank tests, alternative whole blood hema determination
light blue top ac (2)
3.2% sodium citratie
CTAD citrate, theophylline, adenosine, dipyridamole
angle used for blood smear prep?
most commonly used technique for it?
30 to 45°
two glass slide method/manual wedge technique
distance of blood drop in smear from the frosted glass?
diameter of the drop of blood in blood smear?
length and shape of the smear?
scanning methods used? tail to head? back and forth serpentine?
1cm
2-3mm
2/3 or 3/4 and finger-shaped
Longitudinal and Battlement
Automated Methods: (SLIDE)
BLOOD FILM STAINING:
fixative:
stain:
buffer:
CellaVision HemaPrep®
Centrifugal (Spinner) Type
Coulter LH
Sysmex SP-10
methanol
Wright or Wright-Giemsa
0.05M Sodium Phosphate (pH 6.4)
defined as any stain which contains methylene blue (and/or its products of oxidation) and a
halogenated fluorescein dye (commonly eosin B or eosin Y)
- __ - a basic stain, it colors the nucleus and some cytoplasmic structures a blue or purple color (stained structures are described to be basophilic [e.g., DNA or RNA])
- __ – an acidic stain, it colors some cytoplasmic structures an orange-red color (stained structures are described to be acidophilic [e.g., proteins with amino groups]). most commonly used type of stain in the hematology laboratory
Romanowsky-type stain:
METHYLENE BLUE
EOSIN
STAINING TECHNIQUES FOR BLOOD FILMS:
- Flood the slide with Wright’s stain for 1 to 3 mins, buffer is then added
- Generally, 5 to 10 mins. to stain a batch of slides; ex. Midas III, Hema-Tek, Coulter LH, Sysmex SP-10
- 1 minute only, Uses modified Wright or
Wright-Giemsa stain filtered into a Coplin jar or a staining dish. aged distilled water is used as the buffer
COLORS:
macro: slide color
micro: rbc, wbc nuclei, neutrophil cytoplasm, eosinophil granules
MANUAL
AUTOMATED
QUICK
pink to purple
orange to salmon pink!!, purple to blue, pink to tan with violet to lilac granules, bright orange
- detect “snowplow” effect (presence of more than four times the number of WBCs per field at the lateral edges than the monolayer area) which is unacceptable
- Used also to estimate total WBC count:
Average no. of WBCs per hpf x 2,000 = estimated WBC ct. per μL - When the appropriate area of a blood smear with a normal RBC count is viewed, there are generally about 200 to 250 RBCs per 100x OIF
Used to examine the nuclear details of the white blood cells; Average number of platelets/OIF X 20,000 = estimated plt. ct. per μL
what is the formula for the platelet estimate?
storage of slides
10x Objective Examination
40x High-Dry or 50x Oil Immersion
Objective
100x Oil Immersion Objective
Average no. of platelets per field x total RBC count / 200 RBCs per field
7 days before disposal
___: process of blood cell formation
* Classical marker of hematopoietic stem cells: __
* considered to start around the nineteenth day of embryonic development after fertilization
Two Related Theories (Origin of Hematopoietic Progenitor Cells):
1.) ___
- suggests that each of the blood cell lineages is derived from its own unique stem cell
2.) ___
- suggests that all blood cells are derived from a single progenitor stem cell called a pluripotential stem cell. Most widely accepted theory among experimental hematologists
Hematopoiesis (aka: Hemopoiesis)
CD 34
Polyphyletic Theory
Monophyletic Theory
Three phases of Hematopoiesis:
site: yolk sac; 1st blood cells: ___
(formed during the first 2 to 8 weeks of life)
●Primitive Erythroblasts (PE); important in early embryo-genesis to produce hemoglobin (__ (3)) necessary for delivery of oxygen to the embryonic tissues. it occurs intravascularly (within developing blood vessels)
site: fetal liver; Hb F (Fetal hemoglobin) is the predominant hemoglobin; __ - first fully developed organ in the fetus -size of the thymus
increases during fetal development; major site of __production; __ - produce B cells
site: bone marrow; Hematopoiesis starts in the
bone marrow cavity before the 5th month of fetal development. The bone marrow becomes
the chief site by the end of 24 weeks’ gestation.
MESOBLASTIC/MEGALOBLASTIC; primitive erythroblast; Gower-1, Gower-2 and Portland
HEPATIC; Thymus; T cell; Kidneys and spleen
INTRAMEDULLARY/MEDULLARY/MYELOID
ADULT HEMATOPOIESIS
* Hematopoietic tissues of adults are located NOT ONLY in the __, but also in
the __(4).
* Bone marrow – contains developing erythroid, myeloid, lymphoid, and megakaryocytic cells
– considered to be a primary lymphoid organ with functions equivalent to that of __ (birds)
– is estimated to be capable of generating around:
__ billion RBCs
__ Granulocytes, and
__ Platelets
~ per kilogram of body weight DAILY
bone marrow; lymph nodes, spleen, thymus and liver; Bursa of Fabricius
2.5; 1 billion; 2.5 billion