Kabusu: Lab Technique TQs

Question 1

When should you collect blood from a horse? Why?

Answer 1

Morning

Epinephrine (from exercise/daily stress etc) will cause splenic contractions and artificially increase RBC value

Question 2

When should you take blood from dogs*

Answer 2

Morning, before food

Lipids in food cause hemolysis of sample

Question 3

What tube has a purple top*

Answer 3

EDTA

Question 4

Which tube is the best choice for CBC/hematology? Why? *

Answer 4

EDTA

1) Preserves cell morphology the best
2) Interferes with Romanowsky stain the least

Question 5

You have a sample in a green top tube. You note hemolysis. Which blood parameters will be affected, and how? *

Answer 5

Lithium heparin tube

Increased K+

Increased Phosphate

Increased AST

Question 6

Which two samples require immediate analysis? Within how long? *

Answer 6

Ammonia

CSF

Analyze within 60 minutes

Question 7

Which tube should CSF be collected in? What should be added to it?*

Answer 7

CSF should be collected in EDTA

CSF is low in protein and degrades quickly.

Add bovine serum albuminin (BSA) to stabilize cells. If you dont have BSA, put blood from same dog in –> increases protein –> more stable

Question 8

You have two tests for Lepto: one is highly specific, one is highly sensitive. You can only pick one. Which will you pick for a screening test and why? What type of predictive value will this test have?

Answer 8

The highly sensitive one

• It tests for True Positive and has few False Negatives
• It wil have a high NPV

Question 9

You have two tests for Lepto. One is highly specific and one is highly sensitive. Which will you choose for a confirmatory test? What type of predictive value will it have?

Answer 9

The highly specific test

• Tests the True Negatitves so will have few False Positives
• High PPV

Question 10

How do you calculate sensitivity?

Answer 10

TP/(TP+FN)

Question 11

How do you test specificity?

Answer 11

TN/(TN+FP)

Question 12

In terms of predictive value: if you have high prevalence of a disease in your area, what will the PPV and NPV be?

Answer 12

High PPV

Low NPV

Question 13

In terms of predictive value: if you have a low prevalence of a disease in your area, what will the PPV and NPV be?

Answer 13

Low PPV

High NPV

Question 14

Which is tube of choice for coagulation tests? Why? *

Answer 14

Sodium citrate (blue top)

• Binds poorly with calcium

Question 15

What is very important when doing a CBC and coagulation tests?*

Answer 15

Sample collection!

- Atraumatic venipuncture

- Be successful the first time

Question 16

T/F - it is acceptable to freeze EDTA samples if you wont analzye them for a while*

Answer 16

FALSE! Never freeze as they will expand

Question 17

T/F - when running a CBC, you start by separating plasma and cells*

Answer 17

FALSE - dont do this

Question 18

Which is tube of choice for bile acids*

Answer 18

Plain blood tube (red top)