Laboratory Activity 3: SAMPLE PREPARATION FOR HEMATOLOGY PROCEDURES

Question 1

Some hematology procedures require (?).

Answer 1

whole blood, plasma, serum or defibrinated blood samples

Question 2

It is important that (?) must be adhered to by the laboratory personnel in each step of sample preparation to ensure the generation of reliable and meaningful measurements and results.

Answer 2

appropriate guidelines

Question 3

1. Whole Blood Preparation:
   a. Draw a sufficient (?) corresponding to the volume of the additive/anticoagulant;
   b. To achieve an optimum ratio of blood to additive/anticoagulant, the volume of blood should (1) fill the tube to the (?) indicated on the evacuated tube label, or (2) be according to the appropriate (?) of the sample to the additive/anticoagulant used.
   c. Before clotting occurs, (?) evacuated tube by gentle inversion according to the type of additive/anticoagulant
   d. Label the specimen container with (?).

Answer 3

amount of blood

line
ratio

immediately mix

patient information including the date and time of collection

Question 4

2. Plasma Preparation:
   a. Draw a sufficient (?) into an evacuated tube with the required anticoagulant.
   b. Gently (?) after collection by appropriate number of inversions according to the type of anticoagulant used. Avoid hemolysis of the specimen during collection and mixing.
   c. Immediately centrifuge anticoagulated blood for (?) or refer to speed and duration recommended by the manufacturer of evacuated tube used.
   d. After centrifugation, three layers are formed: (from top to bottom) (?). The plasma should appear (?).
   e. Carefully (?) with a Pasteur pipette and transfer to a test tube. Take care not to disrupt the (?) or transfer any cells.
   f. (?) the sample container

Answer 4

amount of blood

mix immediately

5 10 minutes at 2,500 rpm

plasma, buffy coat, red blood cells
clear without any pink or red tinge

aspirate the plasma
packed red blood cell layer

Label

Question 5

Notes: Do not use (?) to stop centrifuge. Centrifuge blood within (?) of collection. Do not (?) the sample until the plasma is separated from the cells.

Answer 5

brake

2 hours

refrigerate

Question 6

Serum Preparation:
a. Draw a sufficient (?) to yield the serum volume required by the particular test.
b. Allow the tube containing venous blood to stand in an upright position at room temperature for (?) to allow complete clotting to occur.
c. After 20 -30 minutes, check for complete clotting by (?) and when blood does not ooze from the tube, clotting is complete.
d. (?) the sides of the clot using an applicator stick (at a depth of (?)). Rim only once.

Answer 6

amount of blood

20-30 minutes (no longer than 60 min)

inclining the tube gently

Gently rim or ring
1 cm

Question 7

(1) If using a clot activator tube, invert carefully (?) to mix clot activator and blood.
(2) If using a serum separator tube (SST), mix tubes well by carefully inverting the collection tube (?) for clot formation to occur. Avoid hemolysis of the specimen during collection & mixing.

Answer 7

5 -6 times

8-10 times

Question 8

Note: (?) may cause lysis of red cells. If the clot clings to the stick, dislodge the clot from the stick carefully and include the clot for centrifugation. Do not discard the clot.

Answer 8

Repeated rimming

Question 9

3. Serum Preparation:
   e. Centrifuge blood for (?) or refer to speed and duration recommended by the manufacturer of evacuated tube used. Do not use brake to stop centrifuge.
   f. After centrifugation, note the (?).
   g. Carefully (?) with a Pasteur pipette and transfer to a test tube. Take care not to disrupt the packed red blood cell layer or transfer any cells.
   h. (?) for turbidity. Turbid samples should be (?) to remove remaining insoluble matter. Serum should appear (?).
   i. (?) the sample container

Answer 9

5 10 minutes at 2,500 rpm

layers formed

aspirate the supernatant (serum)

Inspect serum
re-centrifuged

clear without any pink or red tinge

Label

Question 10

Notes: (?) prior to complete coagulation may cause fibrin clots to form in the serum. Centrifuge within (?) of collection. Do not (?) the sample until the serum is separated from the cells.

Answer 10

Centrifuging specimens

2 hours

refrigerate

Question 11

4. Microcollection
   a. Perform (?) following the procedure in the previous experiment.
   b. Collect the specimen in both (?). Fill tubes at the opposite end of the colored ring and wipe off blood at exterior of the tube.
   c. Seal unfilled end (end with colored ring) with (?).
   d. Centrifuge tubes (open end pointing towards the center of centrifuge) for (?).
   e. After centrifugation, examine and identify the (?).

Answer 11

capillary puncture

heparinized and non-heparinized capillary tubes

seal-ease clay, then with paraffin

5 minutes at 12,000 rpm

layers formed

Question 12

5. Defibrination:
   a. Place (?) in a clean Erlenmeyer flask.
   b. Immediately after venipuncture, (?) into the prepared Erlenmeyer flask.
   c. Plug top of flask with (?) to prevent specimen contamination and rotate the flask for about (?) until the beads (or clips) are covered with fibrin and no longer make a rattling noise.
   d. Carefully (?) the defibrinated blood into a test tube.

Answer 12

sterile glass beads or paper clips

add the whole blood

gauze or cotton
10 minutes

aspirate and transfer

Question 13

Note: Perform defibrination(?).

Answer 13

before the blood clots