Indicies

Question 1

Calculating MCV

Answer 1

hct/rbc x 10

Question 2

Calculating MCH

Answer 2

Hgb/RBC x 10

Question 3

Calculating MCHC

Answer 3

Hgb/Hct x 100

Question 4

WBC count

Answer 4

(# cells counted x dilution x 10)/ #squares counted

Question 5

RBC count

Answer 5

(# cells counted x dilution x 10)/ (1/5)

Question 6

platelet count

Answer 6

(#cells counted x dilution x 10) / # squares counted

Question 7

absolute WBC value calculation

Answer 7

% value x total WBC count

Question 8

rule of 3

Answer 8

RBC x 3 = Hgb

Hgb x 3 = Hct

Question 9

Which value determines microcytic/ normocytic/ macrocytic? (RBC size)

Answer 9

MCV

Question 10

Hematocrit definition

Answer 10

volume of RBC/ Volume of WB x 100

Question 11

Microhct sources of error

Answer 11

poorly drawn
dilution
hemolysis
clot
low volume draw
parallx reading error
trapped plasma (by ab. shaped RBCs)

Question 12

Retic count

Answer 12

retics/ 10 = % retic count

Question 13

retic count sources of error

Answer 13

stain (must use supravital stain)
artefact
refractile inclusions
other inclusion bodies (howell-jolley, pappenheimer, heinz, basophilic stippling)

Question 14

erythrocytes sedimentation rate uses what kind of blood sample?

Answer 14

anticoagulated blood (EDTA, sodium citrate)

Question 15

What are the 3 stages of erythrocyte sedimentation?

Answer 15

rouleaux
maximum sedimentation
RBC packing

Question 16

normal sedimentation rates

Answer 16

m: 0-10 mm/hr
f: 0-20 mm/hr

Question 17

causes of increased ESR error

Answer 17

physiologic: increased fibrinogen/gamma globulin, anemia, macrocytic RBCs, increase plasma volume, inflammation
non-physiologic: increased temp >27, dirty equipment, increase bore of tube, non-vertical tube, rack/tube movement

Question 18

causes of decreased ESR error

Answer 18

physiologic: increase albumin, microcytic RBCs, ab. RBC shape
non-physiologic: decreased temp <22, clots, hemolysis, old specimen, decrease tube bore, bubbles in tube

Question 19

Cell count significance: Increased RBC (erythrocytosis)

Answer 19

polycythemia
lung disease
malignancy
dehydration

Question 20

cell count significance: RBC decrease (erythocytopenia/ anemia)

Answer 20

iron deficiency
bleeding
hereditary disorders

Question 21

cell count significance: Platelet increase (thrombocytosis)

Answer 21

inflammation
malignancy
acute phase reactant

Question 22

cell count significance: platelet decrease (thrombocytopenia)

Answer 22

bm disease

platelet distruction

Question 23

manual cell count sources of error

Answer 23

clotted sample
improper mixing
dirty equipment
dilution error
improper filling of hemacytometer
contaminated fluid
inadequate settling time
drying of dilution
calculation errors

Question 24

cell count significance: wbc increase (leukocytosis)

Answer 24

bacterial infection
inflammation
malignancy

Question 25

cell count significance: wbc decrease (leukopenia)

Answer 25

viral infection

chemotherapy