Lab Tech Lab Exam 1

Question 0

Can the CBC and thrombocyte eval tests be done in house or sent out?

Answer 0

Both can be done in house

Thrombocyte count can be sent out with 2 unstained blood smears

Question 1

What tube is needed for the CBC and thrombocyte evaluation?

Answer 1

Purple top

EDTA

Question 2

What should always be done to confirm automated CBC results?

Answer 2

Automated platelet counts should be verified by examination of a stained blood smear.

Question 3

Does thrombocyte eval determine abnormalities in the primary or secondary phase of hemostasis?

Answer 3

Primary, mechanical

Question 4

Describe, in detail, the steps for manually performing CBC and thrombocyte eval.

Answer 4

Make diagnostic blood smear
Should be performed within 5 hours of collection
Look in monolayer
Count average number of platelets per oil immersion field (10 fields)
Multiply average by 15,000

Question 4

.

Answer 4

.

Question 5

How can platelet clumps affect thrombocyte counts?

Answer 5

Platelet clumping will make the count seem low.

Question 6

When reviewing a blood smear for confirmation, what area of the blood film are you most likely to see this in?

Answer 6

Monolayer?

Question 7

Describe in details the steps for running the buccal mucosal bleeding time test.

Answer 7

Patient may need to be anesthetized or sedated
Upper lip tied back with gauze to expose mucosal surface
Lancet used to create a small incision in the mucosa above the premolars
Incision allowed to bleed and is blotted below (not touching!) the incision site with filter paper every 5 sec until would is no longer bleeding

Question 8

Can the BMBT test be sent out to a lab?

Answer 8

No, only in vivo test for primary hemostasis and must be performed in house

Question 9

Is the BMBT test used for primary or secondary phase of hemostasis?

Answer 9

Primary, mechanical

Question 10

What is the normal time for the BMBT test in a dog?

Answer 10

1-5 min

Question 11

If BMBT is prolonged, what medical conditions could cause this to occur?

Answer 11

Evaluates vascular integrity, platelet numbers, function, and vWF

Question 12

What tube is needed for the activated clotting time test, ACT? What is in the tube?

Answer 12

Gray top tube

Diatomaceous earth

Question 13

Can the ACT test be done in house or sent out?

Answer 13

In house

Question 14

Is the ACT test used to evaluate the primary or secondary phase of hemostasis?

Answer 14

Secondary (chemical)

Question 15

What portion of the coag cascade is evaluated for the ACT test?

Answer 15

Intrinsic and common pathways

Question 16

Describe in detail the steps for running the ACT

Answer 16

Gray top tube must be warmed to 37C (98.6F) to evaluate clot formation
2 mls of fresh, whole blood (without anticoagulant) is added to a special tube containing diatomaceous earth as a contact activator
Invert tube gently to mix
Place tube back into heat source

Question 17

What is the normal ACT time for a dog?

Answer 17

60-90 sec

Question 18

What is the normal ACT for a cat?

Answer 18

45-160 sec

Question 19

If ACT is prolonged, what medical conditions could cause this to occur?

Answer 19

Can demonstrate severe clotting factor deficiencies, but insensitive compared to PTT

Question 20

What tube is needed for a Prothrombin (PT) test? What anticoagulant is present in this tube?

Answer 20

Blue top tube

Citrate

Question 21

Can the PT test be done in house or sent off?

Answer 21

Either

Question 22

Is the PT used to evaluate the primary or secondary phase of hemostasis?

Answer 22

Secondary or chemical phase

Question 23

Which portion of the coag cascade is evaluated with the PT test?

Answer 23

Extrinsic and common pathway

Question 24

If prothrombin time is prolonged, what medical conditions could cause this to occur?

Answer 24

Severe liver disease
DIC (disseminated intravascular coagulation)
Hereditary or acquired deficiencies of extrinsic or common pathway factors
Vit K deficiency/antagonist
Early rodenticide toxicity (within 24hrs)

Question 25

What tube is needed for the Activated Partial Thromboplastin Time, PTT? What anticoagulant is present in the tube?

Answer 25

Blue top tube

Citrate

Question 26

Can the PTT test be done in house or sent off?

Answer 26

Either

Question 27

Is the PTT test used to evaluate the primary or secondary phase of hemostasis?

Answer 27

Secondary or chemical

Question 28

Which portion of the coag cascade is evaluated in the PTT test?

Answer 28

Intrinsic and common pathways

Question 29

If PTT is prolonged, what medical conditions could cause this to occur?

Answer 29

Deficiency of intrinsic or common pathway factors
Severe liver disease
DIC
Vitamin K deficiency/antagonist
Over-heparization

Question 30

List the steps, in detail, for performing a rapid major cross match.

Answer 30

Major: recipient plasma and donor RBC
1 drop donor blood (EDTA), 1 drop recipient serum, 2 drops saline
Place on glass slide and swirl to mix
Equal volumes needed for accuracy

Question 31

List the steps, in detail, for performing a major and minor cross match.

Answer 31

Obtain 1 ml of blood from recipient and place in EDTA tube
Obtain 1 ml of blood from donor and place in EDTA tube
Separate plasma from RBCs via centrifugation of both tubes, at blood speed for 10 min
Separate plasma and packed RBCs into 4 separate plastic tubes, labeled donor plasma, recipient plasma, donor RBCs, recipient RBCs
Suspend 0.2 mls of donor RBCs into 4.8 mls or 0.9% saline and gently mix
Do the same with recipient RBCs
Prepare 4 slides as follows:
(1) 1 drop donor plasma, 1 drop donor rinsed RBCs
(2) 1 drop recipient plasma, 1 drop recipient rinsed RBCs
(3) minor: 1 drop recipient rinsed RBCs, 1 drop donor plasma
(4) major: 1 drop recipient plasma, 1 drop donor rinsed RBCs

Question 32

What do you look for grossly in most species, to determine if cross match is compatible?

Answer 32

Agglutination

Question 33

If agglutination is present, what must you differentiate microscopically?

Answer 33

Agglutination must be differentiated from rouleaux formation