Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
67 Cards in this Set
- Front
- Back
how many primary squares are there in a hemocytometer |
9 |
|
how many secondary squares are in one primary square |
25 |
|
how many tertiary squares are in a secondary square |
16 |
|
Manual cell calculation |
Average # cells X dilution X 10 (depth) divided by-------------------------------------- # of primary squares |
|
which squares and how many do you count for: WBC RBC plts |
WBC: 4 primary RBC: 5 secondary PLT: 10 secondary |
|
What are the dilution factors for WBC RBC PLT |
WBC: 1:100 RBC 1:200 PLT: 1:100 |
|
What component in unopette lyses RBC? |
ammonium oxalate |
|
scientific notation for: WBC RBC PLT Eos |
WBC: one decimal X 10^3 (4.4-11.0) RBC: two decimals X 10^6 (4.00-5.90) PLT: no decimal X 10^3 (150-400) Eos: whole # (542/mm^3) |
|
The error range on two counts on a hemocytometer need to be how close to each other? |
+/- 10% |
|
Hgb determination: cyanmethemoglobin method Reagent: Components: What absorbance is used? |
Reagent: Drabkins Components: 1. potassium ferricyanide (oxidizes Hgb to methemoglobin - ferric +3 state) 2. potassium cyanide converts methemoglobin to cyanmethemoglobin Abs at 540nm |
|
What is the calculation for hemoglobin concentration using the cyanmethemoglobin method? |
make sure to have the concentration value in g/dL in calc |
|
how do you calculate the dilution factor |
total volume/sample volume |
|
Hemoglobin reference ranges for male and female |
male: 13.5-17.5 female: 12.0-16.0 g/dL |
|
T/F: drabkins reagent is sensitive to light |
True, dat.. |
|
and icteric sample has too much what in it |
Marco bili-rubio.... no, wait. Bilirubin. Too much bilirubin. |
|
what is an example of an abnormal Hgb that is resistant to lysis |
Hgb S and C |
|
what is a safer alternative to the cyanmethemoglobin method for hemoglobin determination. HOW is it different? What Abs is used? |
SLS: Sodium lauryl sulphate Lysis BOTH RBC and WBC. Hgb is oxidizes to ferric +3 state and then combines with SLS to be a hemochrome mol Abs at 555nm |
|
what is the def'n of hematocrit reference ranges for male/female: |
percentage of whole blood that is occupied by RBCs (always done in duplicate) male: 41-53% female: 36-46% |
|
rule of three: what is it used for? |
RBC x 3 = Hgb Hgb x 3 = Hct 4, 12, 36 Used to verify the integrity of the sample |
|
What are the RBC indices? |
MCV, MCHC, RDW |
|
MCV: Mean cell volume def'n: calculation: Ref range: ____ - _____ units? |
Def'n: ave size of RBC (indicator of micro/macrocytosis) calculation: Hct x 10 / RBC in millions Ref. range: 80-96 fL |
|
Mean cell hemoglobin (MCH) def'n: calculation: Ref range: ____ - _____ units? |
Def'n: ave weight of Hgb per RBC (does NOT indicate chromia) calculation: Hgb x 10 / RBC (in millions) Ref range: 29-32 pg |
|
Mean cell hemoglobin (MCHC) def'n: ....indicates calculation: Ref range: ____ - _____ units? don't need to memorize. |
def'n: average amount of red cell volume occupied by Hgb... indicates normo or hypochromia calculation: (Hgb / Hct) x 100 Ref range: 33.4-35.5 g/dL |
|
Low MCV and Low MCHC = |
Hypochromic and microcytic |
|
MCHC What are the "critical" high and low to remember? |
< 30 should not occur >36 should not occur unless you have spherocytes .... lost membrane, normal Hgb, low Hct |
|
causes of a high MCHC >36 besides spherocytes |
cold agglutinin lipemia (turbidity) hemolysis (free hgb) icteric (bilirubin abs) |
|
Red cell distribution width (RDW): CV def'n... it quantitates... ref. range: Calculated: |
def'n: amount of red cell size variation, quantitates anisocytosis ref. range: 11.5-15.0 g/L directly calculated from RBC histo = 1 SD/MCV x100% |
|
Red cell distribution width (RDW): SD calculated using: ref. range |
calculating the width in fL at the 20% height level on the RBC curve ref. range: 39-47 fL |
|
last immature stage in RBC dev: characteristics: |
reticulocytes. its right before it loses its nucleus spends two days in marrow, and one day in peri contains remnant cytoplasmic RNA |
|
what stain is used for retics |
supravital stain (New Methylene Blue) |
|
what does the reticulocyte count measure? increased: decreased: |
measures erythropoietic activity of the bone marrow increased: bone marrow compensating decreased: bone marrow lacks RBC to release to circulation |
|
how many "dots" does a reticulocyte need to be considered a reticulocyte? |
more than 2 dots |
|
if you counted 60 retics, what is the percent? |
6.0% |
|
how do you perform a retic count using a miller disc |
Count # of red cells AND reticulocytes in small square count # of retics in the big square Count until you get 111 in the small square, divide by 10 |
|
how to calculate a corrected retic count... what does it correct for? when do you correct? |
Corrected reticulocyte count corrects for an abnormal hematocrit value Retic % = raw retic % x (pt. Hct / 45) Correct anytime the pts Hct is less than 45 (they have anemia) |
|
reticulocyte production index (RPI) def'n: calculation: |
reticulocytes produced on a daily basis calculation: corrected retic / # d to mature for every 2% Hct deviation from 45% the maturation rises 0.1 days. >3.0% is an adequate response |
|
Reference range for raw retic, corrected retic, and RPI |
0.5-1.5% NORMAL |
|
how long do RBC survive normally |
120d |
|
erythrocyte sedimentation rate (ESR) |
Rate of RBC settling in 1 hour mm/hr directly proportional to RBC mass (heavier = faster = more Hgb). inversely proportional to plasma viscocity (more viscous = slower) Useful for monitoring disease or differentiating btwn similar diseases |
|
How do the following affect ESR: Albumin zeta potential fibrinogen, globulins |
Albumin: decreases it.. more viscous zeta potential: decrease it... RBC repel each other proteins: increases it cause they cover up neg. charges |
|
ESR ref ranges |
male: 0-20 female: 0-30 |
|
Ref. range: MCV MCH MCHC |
MCV: 80-96 fL MCH 29-32 pg MCHC: 33.4-35.3 g/dL |
|
MCHC # < _______ = hypochromasia MCV > ____ = macrocytic MCV < ____ = microcytic |
MCHC <32 = hypochromasia MCV >100fL = macrocytic MCV <80fL =microcytic |
|
Coulter principle: threshold is.. the area between thresholds is called |
thresholds are the set limit, the area between them is a channel |
|
Abnormal RBC histogram |
Cold agglutinin |
|
NORMAL |
Most RBCs fall between 80 and 100fl. The histogram should start at thebaseline on the left and a small “tail” may be evident on the right. This represents doublets and triplets (cellsthat go through the aperture in twos and threes). |
|
Abnormal RBC histogram |
MACROcytosis, target cells |
|
Abnormal RBC histogram |
Dimorphic RBC population, high RDW, anisocytosis, post-transfusion |
|
Abnormal RBC histogram |
Giant plt, RBC fragments |
|
NORMAL PLT histogram |
The PLT histogram has twocurves. One is the curve created fromthe directly measured PLT count and the other is Coulter’s patented curvefitting process which allows an accurate PLT count without interference from microcyticRBC or RBC fragments. |
|
|
NORMAL WBChistogram. LBMEN. The lymphocytes (smallest cell) fall to the far left of the histogram. The lymphs are followed by the Basos,MonosEos and Neutrophils. Basophilic granules are water soluble, lose some of the granules when the basophils are put in solution. When this happens, the cell cytoplasm shrinksdown around the nucleus and the few remaining granules and makes the cellappear smaller than it is in vivo. |
|
|
Immature neutrophils |
|
|
Lymphocytosis, literally no other cell types |
|
|
Varient lymph (reactive lymph) the peak is slightly shifted over to the right |
|
|
immature neutrophil = shift to the left |
|
|
Eosinophila, they are in the neutrophil range |
|
|
Blasts |
|
In VCS tech, the following measures... (Y) VOLUME= (Z) CONDUCTIVITY= (X) LIGHTSCATTER = |
VOLUME= SIZE CONDUCTIVITY= INTERNAL COMPOSITION LIGHTSCATTER = CELL SHAPE / SURFACE |
|
|
NORMAL data plot |
|
|
|
|
|
The strange “blip” at the end ofthe PLT histogram is indicative of very microcytic RBCs and RBC fragments thatare small enough to get in under the 20fl cutoff. In this instance it would be important toverify the PLT count. |
|
|
Auer rods aredefined as acoalescence ofthe azurophilicgranules and areonly seen in non-lymphocyticleukemias |
|
MYELOPROLIFERATIVE DISORDERS |
Defined as a hypercellular bonemarrow with increased quantities of one or more of the cells lines:erythrocytes, leukocytes or platelets in the peripheral blood. It is thought to be a neoplastic, clonalproliferation of a single multipotential stemcell w/ one cell line predominating and often transforming into another. |
|
Sysmex - WBC. Measurethe forward scatter, side scatter and side fluorescence of the WBC populations |
Measurethe forward scatter (SIZE), side scatter (internal structure) and side fluorescence (RNA/DNA info) of the WBC populations |
|
Placementof cells in the scattergram is based on the size (forward scatter),internal composition (side scatter) |
|
|
diff scatter.. memorzie locations |
|
|
Sysmex-Hemoglobin uses what method |
SLS. Step one is denaturation of theglobin molecule. Step 2 is oxidation of the hememolecule. Finally Step 3 where the SLShemoglobin is converted to SLS hemoglobin which is read photometrically. |