week 1 study questions

hemo

what is the EDTA phenomenon

low platelet count due to EDTA-induced aggregation of platelets

what is pseudothrombocytopenia

another name of EDTA phenomenon

what can the lab do to resolve specimens affected by the EDTA phenomenon

can be prevented w/ sodium citrate and collected/reviewd at 37C, but not always

what does EDTA phenomenon indicate

it is only an in-vitro phenomenon and has no clinical significance

what needs to be done if a blue top is run on the XN

whenever a blue top is used, the result must be multiplied by 1.1 to make up for the 9:1 blood:anticoagulant

How long is too long for a tourniquet

a min

what is the effect of a tourniquet that is left on too tightly or too too long on CBC

causes hemoconcentration causing false increased in all cells and proteins in a sample specifically RBC and HGB

what is the affect of excessive foot/finger squeezing during a microstick on a CBC

hemolysis, false decrease due to extravascular fluid dilution, abnormal morphology

what is the effect of venipuncture above an IV line on a CBC

containment/dilution by IV fluid, slight-extreme decreased in Hb, RBC, WBC, Plt

what are the effects of a slow fill or the tubes or difficult sticks on CBC

hemolysis, clotting, delay in mixing w/ anticoagulant

what is the anticoagulant of choice for hematology testing, why?

EDTA K2 or EDTA K3, neither of these distort morphology

how does EDTA prevent coagulation

removing calcium from the blood

what are the results and storage requirement to achieve CBC results

room temp-24; refrigeration-48 hrs

what is the prefered storage for CBC samples

refrigeration!

what happens to a room temp blood sample when it is let sit out for longer than 24 hrs

MCV icreases

what needs to be done to a sample if it has been refrigerated

it must come up to temp before use and needs to be mixed well

what tube color is K3 EDTA

dark purple

what is the difference between K2 and K3

K3 has a higher concentration of EDTA while K2 has a higher volume

what color are K2 EDTA tubes

pink

Can cord blood be accepted for CBC

no

what is the diagnostic significance of the CBC

anemias, leukemias, allergic reactions, viral bacteria and parasitic infections

what is done when a hemolytic, lipemic, or icteric samples are received

hight speed centrifuge, replace lipemic plasma, correct the measurement

what is done if HIL sample is recieved for a CBC, but is not treated first

HGB will be falsely increased

what happens to a clotted specimen that is given to hemo

reject

what happens if the lab receives a short draw to perform a CBC

a manual test is done after the sample is transfered to a microtainer and add a note that says “quantitiy not suffiient”

what is done when a frozen sample arrives for a CBC

reject

what is done when a shared sample that has already been centrifuged and sampled before it is given to Hemo for a CBC

reject as it can’t be centrifuged twice and the plasma can’t be resampled

what are the 3 fractions of blood

plasma (yellow); wbc and plt (white)'; rbc (red

what does the plasma aspect of blood contain

water, proteins, nutrients, and hormones

what percentage of blood is plasma

55%

what percentage of blood is WBC and platelets

1%

what percentage of RBC is blood

44%

how does anemia affect blood fraction percentages

low Hct, increased plasma, low RBC and Hb, usually doesn’t affect WBC or plt

hos does polycythemia affect blood fraction percentages

high Hct, elevated RBC, thicker blood (hyperviscocity), increase in all cell lines

what is the problem with blood that is too thick

increases clotting

how is plasma made

blood is allowed to separate natrually and doesnt require clotting

What is plasma specifically good for study

more representative of the body’s blood composition

what tests use plasma

coag or immediate study

how is serum made

blood is allowed to clot for 30-60 min then centrifuged

what is serum specifically good for testing

higher levels of certain analytes

what tests often use serum

chem, antibody/antigen testing

what is the alternative hemocytometer ruling used less commonly

Fuchs-Rosenthal with a depth of 0.2mm

What is the standard dilutent for manual RBC counts in lab and its tonicity

0.9% saline which is isotonic

what does isotonic mean specifically in hemo

it matches the osmotic pressure of blood and other bodily fluids

what is tonicicty

the ability of a solution to modify the volume of cells by altering their water content

what volume of sample and dilution are used for slightly bloody or slightly cloudy samples

1:20 w/ 100uL of specimen and 1980uL of saline

what volume of sample and dilution are used for moderately bloody or cloudy samples

1:100 w/ 20uL of specimen and 1990 uL of saline

what volume of sample and dilution are used for grossly bloody or turbid samples

1:200 W. 10 (or 20)uL and 1990 (or 3.98) mL

why are both sides of the hemocytometer utilized

this is so 2 techs can view the samples separately for quality control and percision

what is the normal range of RBCs for men

4.4-5.8 × 10^6 mcL

what is the normal range of RBCs for women

308-5.3 × 10^6 mcL

what is the normal range of RBCs for children

3.8-5.3 × 10^6 mcL

what is the normal range of RBCs for newborns

4.5-6.4 × 10^6 mcl

what is the normal range of WBCs for men

4-12 × 10³ mcL

what is the normal range of WBCs for women

4-12 ×10³ mcl

what is the normal range of WBCs for children

4-12 × 10³ mcl

what is the normal range of WBCs for newborns

5-21 × 10³ mcl

what is the RDW-CV

RBC distribution width coefficient of variation

what is indicated when the RDW-CV is increased

high anisocytosis= large variation in the size of RBCs

what can cause and increase in MCH and MCV (>100)

B12 or Folate deficienty, liver disease, alcoholism, thyroid dysfunction, chemotherapy

how and why is the MCHC used as a QC instrument

it is usually stable when both MCH and MCV are out of range and can often indicate an instrument malfunction

what is the formula for calculating the number of cells counted in a hemocytometer

cells/ml = (total cells x dilution x depth) / (Z/25) where Z= squares counted

how many squares are counted during a RBC hemocytometer count

5/25

how many squares are used during a WBC count with a hemocytometer

100/25

what is the standard hemocytometer rulling

Neubauer; when a cell is on a line count the cells on the right and top, but not the left and bottom

what is the stained material appearing in reticulocytes

RNA

what is indicated by reticulocytosis

an increased need for RBCs; can be caused by trauma, blood loss, pregnancy, hemolytic anemia

what are some disease states where reticulocytes are increased

hemolytic anemia, blood loss, pregnancy

what are some disease states where reticulocyte % is decreased

IDA, aplastic cirrhosis, B12/folate deficiency, myelocysplastic syndrome, megalosplatic anemia, aplastic anemia

what is the chemical used to remove oil from slides

histoclear

describe how to perform a WBC estimate. What is the acceptable limit when correlating with the automatic count

on a monolayer at 50x oil; (WBC counted / # of fields) x 3; within 20%

describe how to perform a Plt estimate. What is the acceptable limit when correlating with the automatic count

on a monolayer at 100x oil; (PLT counted / # of fields) x 15; within 20%

what are absolute WBC counts

# of a specific WBC present

what are relative WBC counts

percentage of wbc cells counted

what is the formula for relative WBC count

% of specific WBC / total WBC count

what is the normal relative range in neutrophils in men

40-68

what is the normal relative range in neutrophils in women

47-73

what is the normal relative range in neutrophils in children

40-73

what is the normal relative range in neutrophils in newborns

45-81

what is the normal relative range in lymphocytes in men

19-49

what is the normal relative range in lymphocytes in women

18-42

what is the normal relative range in lymphocytes in children

14-43

what is the normal relative range in lymphocytes in newborns

10-40

what is the normal relative range in monocytes in men

3-13

what is the normal relative range in monocytes in women

4-12

what is the normal relative range in monocytes in children

3-13

what is the normal relative range in monocytes in newborns

1-17

what is the normal relative range in eosinophils in men

0-8

what is the normal relative range in eosinophils in women

0-8

what is the normal relative range in eosinophils in children

0-5

what is the normal relative range in eosinophils in newborn

0-8

what is the normal relative range in basophils in men

0-1

what is the normal relative range in basophils in women

0-1

what is the normal relative range in basophils in children

0-1

what is the normal relative range in basophils in newborns

0-1

what is the normal absolute range in neutrophils in men

1.4-5.3

what is the normal absolute range in neutrophils in women

1.6-7.7

what is the normal absolute range in neutrophils in children

2.3-7.8

what is the normal absolute range in neutrophils in newborns

3.4-21.0

what is the normal absolute range in lymphocytes in men

0.9-3.3