(P) Lesson 4: Special Collection and Handling for Hemostasis Laboratory

Question 1

What are the two (2) most commonly encountered tests in a hemostasis laboratory?

Answer 1

1. Prothrombin Time (PT)
2. Partial Thromboplastin Time (PTT)

Question 2

What two (2) specific clotting factors were mentioned to be prone to deteriotation?

Answer 2

1. Factor V
2. Factor VIII

Question 3

The deterioration of clotting factors may result in what?

Answer 3

Prolonged coagulation time

Question 4

T or F: Special collection and handlng of blood samples for PT and PTT are crucial to ensure accurate and reliable results.

Answer 4

True

Question 5

What are some of the factors to be considered in samples for PT and PTT tests?

There are three (3) mentioned answers here.

Answer 5

1. Temperature
2. Anticoagulant used
3. Method of Collection

Question 6

Ideal specimen for platelet function or clotting factor assessment?

Answer 6

Citrated blood collected using blue top

Question 7

What two (2) reasons behind why citrated blood is used for platelet function and clotting factor assessment?

Answer 7

1. Chelates calcium
2. Preservation of all clotting factors

Question 8

Ideal Specimen

• Acts as a chelating agent, binding to calcium ions in the blood

Answer 8

Citrate

Question 9

Ideal Specimen

• Essential for the coagulation cascade
• Citrate prevents the formation of blood clots by chelating ____

Answer 9

Calcium

Question 10

Ideal Specimen

T or F: Citrate alters the activity of the clotting factors.

Answer 10

False

They do not alter the activity.

Question 11

Ideal Specimen

There are two (2) clotting factors that are considered as labile factors since they are sensitive and deteriorate easily in certain anticoagulants (e.g. EDTA).

Answer 11

Factor V and Factor VIII

Question 12

Ideal Specimen

Factors in the coagulation cascade that are sensitive to change in temperature, time, and handling during the blood collection and processing

Answer 12

Labile clotting factors

Question 13

What is the principle behind using whole blood in coagulation tests?

Answer 13

No anticoagulant is used and the whole blood is allowed to clot.

Question 14

What three (3) tests in the hemostasis laboratory uses whole blood?

Answer 14

1. Clotting Time
2. Clot Retraction Time
3. Whole Blood Clot Lysis Time

Question 15

Whole Blood Specimen

What are the three (3) different methods in measuring clotting time?

Answer 15

1. Slide Method/Drop Method
2. Lee and White Method
3. Capillary Tube Method

Question 16

Whole Blood Specimen

• Measures the time it takes for blood to clot
• Determines if there are problems under the common and intrinsic pathways?

Answer 16

Clotting Time

Question 17

Whole Blood Specimen

• One of the special tests used for evaluation of platelets

Sorry, yan lang talaga malalagay ko. 💔

Answer 17

Clot Retraction Time

Question 18

What are the two (2) types of tests for clot retraction time?

Answer 18

1. McFarlan Method
2. Hirschboeck Method

Question 19

Whole Blood Specimen

• Measures the stability of the clot within 48 hours

Answer 19

Whole Blood Clot Lysis Time

Question 20

Serum Specimen

Pop Quiz: What are the clotting factors under the fibrinogen group?

Answer 20

1. Factor I
2. Factor V
3. Factor VIII
4. Factor X
5. Factor XIII

Balik ka muna sa secondary hemostasis if hindi mo ‘to nasagot. 😠

Question 21

Serum Specimen

The clotting factors of the ____ group are completely absent in the serum since they are completely consumed/

Answer 21

Fibrinogen

Question 22

Serum Specimen

How much of the residual prothrombin or Factor II is left in the serum?

Answer 22

About 20% or less

Question 23

Serum Specimen

What are the two (2) tests that use serum as a sample?

Answer 23

1. Serum Prothrombin Time (Serum PT)/Thrombin Consumption Test
2. Mixing Studies

Question 24

Serum Specimen

• Involves mixing patient plasma with serum
• Used to pinpoint what clotting factor is deficient in the patient’s sample
• Mixes the plasma of the patient to the serum of another individual or the normal serum mix to plasma of the patient before proceeding and repeating PTT after mixing

Answer 24

Mixing Studies

Question 25

# Serum Specimen What **two (2) types of plasma** are under the serum specimen?

Answer 25

1. Platelet Rich Plasma (PRP) 2. Platelet Poor Plasma (PPP)

Question 26

# Serum Specimen * Plasma that contains **higher concentration of platelets**

Answer 26

Platelet Rich Plasma (PRP)

Question 27

# Serum Specimen Within what **range** should a platelet count fall within to be considered as **platelet-rich plasma?**

Answer 27

200,000 to 300,000 platelets/uL

Question 28

# Serum Specimen What are the **three (3) tests** in the hemostasis laboratory that uses **platelet-rich plasma?**

Answer 28

1. Platelet Aggregation Studies 2. Plasma Recalcification Time 3. Plasma Retention Test

Question 29

# Serum Specimen * The ideal specimen for PT/PTT tests as it doesn't require platelets

Answer 29

Platelet-Poor Plasma

Question 30

# Serum Specimen **T or F:** In PT/PTT tests, there should be no cellular elements or contaminants such as RBC, WBC, or platelets present in the plasma.

Answer 30

True

Question 31

# Serum Specimen Why should there be no cellular elements or contaminants in the plasma?

Answer 31

They could interfere with the **accuracy** of the tests.

Question 32

# Serum Specimen Within what **range** should a platelet count fall within to be considered as **platelet-poor plasma?**

Answer 32

Less than 10,000 platelets/uL or total absence of platelets

Question 33

# Serum Specimen What are the **three (3) tests** in the hemostasis laboratory that uses **platelet-poor plasma?**

Answer 33

1. Prothrombin Time (PT) 2. Partial Thromboplastin Time (PTT) 3. Reptilase Time

Question 34

**T or F:** PT/PTT are part of the platelet function tests.

Answer 34

False

Question 35

They are specifically designed to **assess the functionality of platelets** in the blood.

Answer 35

Platelet Function Tests

Question 36

They primarily assess **the clotting function of plasma**, focusing on the clotting factors involved in the intrinsic and extrinsic clotting pathways.

Answer 36

PT/PTT

Question 37

Any abnormal results from the platelet function test will be deemed as ____ or ____ by PT/PTT.

Answer 37

Normal or unaffected

Question 38

# Anticoagulant Used for Coagulation Tests * Ideal to use to preserve all clotting factors, especially **labile clotting factors** such as clotting Factor V and Factor VII

Answer 38

Sodium Citrate

Question 39

# Anticoagulant Used for Coagulation Tests For **PTT requests,** the specimen should be processed immediately within ____

Answer 39

Within 2 hours

Question 40

# Anticoagulant Used for Coagulation Tests If the test requested is for **PT only,** the plasma retrieved can still be used within ____

Answer 40

Within 24 hours

Question 41

# Anticoagulant Used for Coagulation Tests Both specimens for **PT and PTT** are stored at what temperature?

Answer 41

Room temperature

Question 42

What are **two (2) types of sodium citrate concentration?**

Answer 42

1. 3.2% (0.109 M) 2. 3.8% (0.129 M)

Question 43

The two types of sodium citrate concentration are ideal specifically among patients with **increased ____**, frequently seen in patients with ____

Answer 43

Increased **hematocrit value** as seen in **polycythemia vera**

Question 44

**T or F:** Relative polycythemia vera causes a false increase in the hematocrit value.

Answer 44

True

Question 45

**T or F:** Dehydration causes a false decrease in hematocrit value.

Answer 45

False (False increase)

Question 46

**T or F:** Absolute polycythemia vera causes a true increase in hematocrit.

Answer 46

True

Question 47

If the hematocrit value has reached ____, it will affect the PT/PTT results.

Answer 47

> 52%

Question 48

If the hematocrit exceeds ____, there will be an excess of citrate in the specimen.

Answer 48

0.50 L/L

Question 49

Excess of citrate in the specimen causes ____ of coagulation time tests.

Answer 49

Prolonged coagulation

Question 50

# Remedy Used for Increased Hematocrit Value This formula is used to determine the amount of anticoagulant that we have to remove from that particular tube due to high hematocrit value.

Answer 50

C = (1.85 x 10^-3) x (100 - Hct) x Vol

Question 51

# Remedy Used for Increased Hematocrit Value **T or F:** Authors recommend to not open the blue top tube before testing or separating plasma from the specimen.

Answer 51

True

Question 52

# Remedy Used for Increased Hematocrit Value Use ____ citrate concentration if the patient has high hematocrit.

Answer 52

3.2%

Question 53

# Remedy Used for Increased Hematocrit Value What ratio should be maintained in any test if you are mixing the blood to a particular anticoagulant?

Answer 53

9:1

Question 54

# Anticoagulants that should not be used for coagulation tests What are the **three (3) anticoagulants** that should not be used for coagulation tests?

Answer 54

1. Heparin 2. Ethylenediaminetetraacetic Acid (EDTA) 3. Oxalate

Question 55

# Anticoagulants that should not be used for coagulation tests * Has anti-thrombin property * Will inhibit clotting formation

Answer 55

Heparin

Question 56

# Anticoagulants that should not be used for coagulation tests Most coagulation tests rely on the formation of ____ which comes from ____

Answer 56

Formation of thrombin from prothrombin

Question 57

# Anticoagulants that should not be used for coagulation tests * Not ideal for coagulation tests since it makes Factor V unstable

Answer 57

EDTA

Question 58

# Anticoagulants that should not be used for coagulation tests * Not ideal when automated machines are used * Binds to calcium which will form a precipitate that affects the absorbance and transmittance of light

Answer 58

Oxalate

Question 59

# Anticoagulants that should not be used for coagulation tests Most automated machines use ____ for testing PT/PTT.

Answer 59

Light source

Question 60

What are the **two (2)** suggested techniques of collection for coagulation tests?

Answer 60

1. Two-syringe technique 2. Two evacuated tube technique

Question 61

What is the **main objective** of the two collection techniques?

Answer 61

To prevent tissue fluid contamination in our specimen

Question 62

Please review the procedure of the two-syringe method and two evacuated tube method.

Answer 62

Hehe, thanks pi.

Question 63

What are the **five (5)** factors affecting the specimen during blood collection?

Answer 63

1. Tissue Fluid 2. Drug Administration 3. Acidity and Basicity 4. Tourniquet Application 5. Anticoagulant Used

Question 64

# Factors affecting the specimen during blood collection Generally, how do we ensure there is no tissue fluid contamination?

Answer 64

Using two blue tops - discarding the first one and utilizing the second one for coagulation tests

Question 65

# Factors affecting the specimen during blood collection If we conduct a PT test when there is thromboplastin from tissue fluid in our PT reagent, it will lead to what?

Answer 65

Shortened PT test time | Due to excess thromboplastin present

Question 66

# Factors affecting the specimen during blood collection These drugs inhibit platelet function by altering the cyclo-oxygenase metabollic pathway.

Answer 66

Aspirin and other anti-inflammatory drugs

Question 67

# Factors affecting the specimen during blood collection If a patient will undergo platelet function test, they must refrain from taking those drugs at least ____

Answer 67

1 week prior to testing

Question 68

# Factors affecting the specimen during blood collection Why should we not flick or tap the arm?

Answer 68

It can lead to the formation of **lactic acid**

Question 69

# Factors affecting the specimen during blood collection Besides tapping or flicking the arm, what is another way that we can have acidic plasma?

Answer 69

When plasma is left in contact with blood for too long after centrifugation

Question 70

# Factors affecting the specimen during blood collection When the resources or sugars are depleted, cells may enter what pathway due to the absence of oxygen and formation of lactic acid?

Answer 70

Glycolytic pathway

Question 71

# Factors affecting the specimen during blood collection The formation of lactic acid in the plasma due to absence of oxygen can result in what?

Answer 71

Acidosis

Question 72

# Factors affecting the specimen during blood collection **T or F:** Acidosis causes an increase in blood pH and affects clotting factors.

Answer 72

False (decrease)

Question 73

# Factors affecting the specimen during blood collection To avoid having acidic plasma, what **three (3)** things should we remember?

Answer 73

1. Do not tap it 2. Avoid prolonged tourniquet application 3. Separate plasma immediately

Question 74

# Factors affecting the specimen during blood collection **T or F:** CO2 level in the plasma will decrease if not covered and will cause basicity in the plasma.

Answer 74

True

Question 75

# Factors affecting the specimen during blood collection **T or F:** Tourniquet application should not be too tight or prolonged to prevent arterial occlusion and stasis.

Answer 75

False (venous occlusion)

Question 76

# Factors affecting the specimen during blood collection What **two (2)** things may occur when the tourniquet is too tight?

Answer 76

1. Fluid contamination 2. Hemoconcentration of blood

Question 77

# Factors affecting the specimen during blood collection Hemoconcentration of blood causes a ____ result of coagulation tests?

Answer 77

False increase

Question 78

# Factors affecting the specimen during blood collection If we don't use a certain amount of anticoagulant or do not use 3.2% sodium citrate, it causes what type of results for clot-based coagulation tests?

Answer 78

Falsely prolonged results

Question 79

# Factors affecting the specimen during blood collection If PT/PTT test is proceeded, what do we add to bring back the calcium for the blood to clot for polycythemic blood?

Answer 79

Calcium reagent

Question 80

# Factors affecting the specimen during blood collection The process of bringing back calcium for the blood to clot.

Answer 80

Recalcification

Question 81

# Factors affecting the specimen during blood collection **T or F:** Plasma cannot clot without red cells.

Answer 81

False (can)

Question 82

Setting the ____ of the centrifuge is vital in preparing PPP or PRP specimen.

Answer 82

Time and speed/gravitational force

Question 83

# Factors affecting the specimen during blood collection What are the **four (4)** tests that use PPP?

Answer 83

1. PT 2. PTT 3. Thrombin Time 4. Reptilase Time

Question 84

# Match the purpose to the plasma specimen. 1. Assess clotting factors 2. Assess platelet function A. PPP B. PRP

Answer 84

1. A 2. B

Question 85

What are the **three (3)** tests that use PRP?

Answer 85

1. Platelet Aggregation Studies 2. Platelet Retention Test 3. Plasma Recalcification Test

Question 86

# PPP or PRP * Perform a **heavy spin** * Set gravitational force to **2000 to 3000 for 10 to 15 minutes** * Contains approximately **less than 10 x 10^9/L platelets** * Can be stored **at room temperature** * Testing should be done **within 2 hours** * **Stored at 4C** if test cannot be done immediately for not more than 4 hours * If cannot be processed immediately, can be stored in a freezer **(-15C to 20C)** to extend validity for up to 2 hours * Used in **PT/PTT**

Answer 86

PPP

Question 87

# PPP or PRP * Perform **light spin** * Set gravitational force to **less than 200 for 10 to 15 minutes)** * Contains approximatelt **250 x 10^9/L platelets** * More **turbid** appearance * Commonly used for **platelet aggregation studies** * May be left at **room temperature** in capped plastic tubes for **2 hours before testing** * Cannot be stored in a freezer or ref * **Fasting for 6 to 8 hours** is required to decrease turbidity

Answer 87

PRP

Question 88

What are **two (2)** other analytes in the plasma that can be analyzed using a blue top on a cold centrifuge?

Answer 88

1. Beta-thromboglobulin 2. Platelet Factor IV

Question 89

What are the **six (6)** factors that affect blood specimen for coagulation? ## Footnote Feeling ko natanong ko na 'to kanina pero paulit-ulit kasi, yawa.

Answer 89

1. High PCV or HCT 2. Contact with glass surface 3. Hemolysis 4. Premature clotting or presence of clot on blood samples prior to testing 5. Storage temperature 6. pH of blood samples

Question 90

# Factors that affect blood specimen for coagulation High hematocrit values will cause ____ citrate.

Answer 90

Excess

Question 91

# Factors that affect blood specimen for coagulation Glass surface provides a ____ charge, causing platelets to be activated.

Answer 91

Negative

Question 92

# Factors that affect blood specimen for coagulation What are the clotting factors that can be prematurely activated upon contact with glass surface?

Answer 92

Contact Group **(Factor XI, Factor XII, HMWK, PK)**

Question 93

# Factors that affect blood specimen for coagulation If the contact group of clotting factors was activated prematurely because of contact with the glass surface, the PTT result will be ____ because there is lower concentration of clotting factors.

Answer 93

Prolonged

Question 94

# Factors that affect blood specimen for coagulation **T or F:** Glass syringe may be used for PTT.

Answer 94

False

Question 95

# Factors that affect blood specimen for coagulation **T or F:** Always reject hemolysed specimen.

Answer 95

True

Question 96

# Factors that affect blood specimen for coagulation Why don’t we accept hemolysed sample for PT/ PTT and certain coagulation tests?

Answer 96

Once red cells are damaged, ADP and tissue thromboplastin-like component is released.

Question 97

# Factors that affect blood specimen for coagulation The release of ADP and the thromboplastin will cause a lowering of the concentration of clotting factors which will cause ____ of the result of PT/PTT.

Answer 97

Prolongation

Question 98

# Factors that affect blood specimen for coagulation Specimen collected ____ should be rejected.

Answer 98

More than 2 hours ago

Question 99

# Factors that affect blood specimen for coagulation Decreases the concentration of CF and causes clumping of platelets

Answer 99

Premature clotting

Question 100

# Factors that affect blood specimen for coagulation **T or F:** The plasma on a centrifuged blue top should immediately be transferred to another tube.

Answer 100

True

Question 101

PT measures what pathway/s?

Answer 101

Extrinsic and common pathway

Question 102

PTT measures what pathway/s?

Answer 102

Intrinsic and common pathway

Question 103

If the person is ____ deficient and tests for PT and PTT, the result would be **normal.**

Answer 103

Factor XIII | Because Factor XIII is part of the common pathway.