Hematology: Sample Collection and Handling

Question 1

Sample collection

Answer 1

Need to know which tests are being run before you start so you know how much blood you need

Question 2

What two pieces of equipment are needed to draw blood?

Answer 2

Needle and Syringe

Question 3

What happens if the needle is too small?

Answer 3

Can cause hemolysis

Question 4

What happens if the syringe is too large?

Answer 4

Can collapse the vein

Question 5

What happens if the syringe is too small?

Answer 5

May not get enough blood with one puncture and have to repeat

Question 6

What is the preferred method of blood collection?

Answer 6

Vacutainer because you can get multiple samples with one stick

Question 7

What does using a vacutainer ensure?

Answer 7

That the anticoagulant is in the proper ratio to blood

Question 8

What tubes do you need if you need serum

Answer 8

Red top tube (RTT)

Serum seperater tube (SST)

Question 9

What tubes do you need if you need plasma?

Answer 9

Green top tube (GTT)

Blue top tube (BTT)

Question 10

What tubes do you need if you need whole blood?

Answer 10

Lavender top tube (LTT)

Question 11

Plasma

Answer 11

Fluid portion of whole blood (unclotted)
Contains fibrinogen
GTT/BTT
90% water, 10% dissolved constituents

Question 12

Serum

Answer 12

Fluid portion of clotted blood
Does not contain fibrinogen
RTT/SST

Question 13

What does RTT and SST not contain

Answer 13

Anticoagulant

Question 14

What happens during clotting

Answer 14

20 mins
Fibrinogen is converted to insoluble fibrin clot matrix
The clot squeezes out the serum in the centrifuge

Question 15

What has a different protein concentration than serum?

Answer 15

Plasma

Question 16

What do anticoagulants bind?

Answer 16

Calcium

Question 17

When are anticoagulants required?

Answer 17

When whole blood or plasma is needed

Question 18

Can serum or plasma be frozen?

Answer 18

Yes if it is placed into a new tube without the red blood cells

Question 19

What are the abnormal colors of serum?

Answer 19

Icteric
Hemolytic
Lipemic

Question 20

Heparin

Answer 20

Green Top Tube (GTT)

Lithium and sodium heparin

Question 21

What are the benefits to heparin tubes?

Answer 21

Do not need to wait for the tube to clot

Question 22

What are heparin tubes used to obtain

Answer 22

Plasma for clinical chemistries

Question 23

Citrates

Answer 23

Blue top tube (BTT)

Sodium citrate or lithium citrate

Question 24

What does sodium citrate interfere with?

Answer 24

Sodium assays

Question 25

What does sodium citrate prevent?

Answer 25

Clotting by binding with calcium

Question 26

What tests use citrated plasma?

Answer 26

Coagulation tests

Blood transfusions

Question 27

Gray top tubes

Answer 27

accurate glucose testing

Not commonly used

Question 28

What is the rule of thumb?

Answer 28

Get enough to run the test 3 times

Question 29

Well-hydrated animal

Answer 29

(PCV 50%)
50% cells, 50% fluids
10ml blood=5ml fluid

Question 30

Dehydrated animals

Answer 30

PCV 70%
70% cells, 30% fluids
10ml blood=3ml fluid

Question 31

EDTA

Answer 31

Ethylenediamineteraacetic acid

Question 32

Lavender Top Tube

Answer 32

EDTA

Chelates (bonding of) calcium

Question 33

What does LTT not alter?

Answer 33

Cell morphology

Question 34

What tests are LTT tubes good for and what are they not good for

Answer 34

Complete Blood Counts

Chemical Assays

Question 35

What do excessive amounts in LTT cause?

Answer 35

Excessive amounts cause cells to shrink and invalidates cell counts in automatic analyzers

Question 36

What does poking the needle through the top of the tube cause?

Answer 36

Hemolysis

Question 37

What order should the tubes be filled in

Answer 37

Citrate
Plain red
Tiger top/serum separator 
Green/heparin
Lavender
Gray