Sample Collection and Processing

Question 1

Which tube has no additive and can be used to send serum for blood chemistry?

Answer 1

Red top tube

Question 2

Serum separator tube with a gel that promotes clot formation, and can be used to provide serum for chemistry and serology.

Answer 2

Tiger Top/Marble Top

Question 3

Which tube contains EDTA with a K+ salt for anticoagulation by binding calcium?

Answer 3

Purple top tube

Question 4

Which tube is best for sending CBC, PCR, and fluid analyses due to its ability to preserve cell morphology?

Answer 4

Purple top tube

Question 5

What electrolyte abnormalities can be expected in a chemistry sent in a tube contaminated with EDTA?

Answer 5

High K+ and low Ca++

Hyperkalemia and hypocalcemia due to the K+ salt present and the chelation of Ca++ to prevent clotting.

Question 6

The green top tube contains which additive, that prevents clotting by inhibiting thrombin?

Answer 6

Heparin

Question 7

Which tube is best for avian and reptile CBC and chemistry panels because it better prevents lysis of cells?

Answer 7

Green top tube

Question 8

This tube contains citrate as an anticoaglant Ca++ chelator, and is used for coagulation panels (PT, aPTT, FDP)

Answer 8

Blue top tube

Question 9

Why is the gray top tube best to use for serial glucose testing?

Answer 9

It contains fluoride which inhibits glycolysis/glucose metabolism.

Question 10

Which tube contains sodium fluoride oxalate?

Answer 10

Gray top tube

Question 11

Which of the following tubes inhibit clotting by chelating Ca++?

Purple
Green
Blue
Gray
Red
Tiger

Answer 11

Purple - EDTA
Blue - Citrate
Gray - sodium fluoride oxalate

Question 12

What are the best veins to get blood from?

Answer 12

Large veins:
Jugular
Cephalic
Saphenous

Question 13

According to RUSVM, how much blood should we be sending off for a CBC/SMAC?

Answer 13

5mL

Question 14

What can give a falsely decreased platelet count of labs?

Answer 14

Traumatic phlebotomy –> platelet activation and clot formation

Question 15

According to RUSVM, what size needle should we be using for filling blood tubes?

Answer 15

20g or larger

Question 16

ACCORDING TO RUSVM, which tubes should be filled first after a blood draw?

Answer 16

Tubes with anticoagulant. But then also don’t contaminate other tubes with anticoagulant, so I guess, like, remove the needle after the first tube and either use a new needle to fill the other tubes or take the top off the tube and fill the next one without a needle. Seems dumb but ok.

Question 17

Vacuum tubes contain a certain amount of additive that works best with a specific amount of blood.

If a purple, EDTA, tube is underfilled, what cell changes can you expect to see?

Answer 17

Low blood volume will maintain an excess of EDTA and K+ salt, which will shrink erythrocytes.

Changes on labs include falsely low PCV and MCV.

Question 18

When taking blood for a CBC, it should be analyzed within one hour or refrigerated because:

Answer 18

If blood sits out for 24 hours, the erythrocytes will swell, leading to increased MCV

Question 19

What will refrigerating a blood film and freezing a blood sample do?

Answer 19

cause cell lysis

Question 20

You spin down a blood sample for testing, but things get busy and you forget to separate serum from the clot for about 3 hours. What change can you expect to see on the chemistry?

Answer 20

Lower blood glucose levels due to RBCs using it for E.