SPECIMEN COLLECTION AND CONSIDERATIONS

Question 1

the act of obtaining a blood sample from a vein using a needle to a syringe or a stoppered evacuated tube; it is the most common way to collect blood specimens

Answer 1

Venipuncture

Question 2

The major veins for venipuncture are in the:

Answer 2

antecubital fossa, the area of the arm in front of the elbow

Question 3

Located near the center of the antecubital fossa; preferred vein because it is typically large, closer to the surface and the most stationary; least likely to bruise

Answer 3

Median cubital vein

Question 4

Second-choice vein; often harder to palpate than median cubital vein; fairly well-anchored; often the only vein felt in obese patients

Answer 4

Cephalic vein

Question 5

Last choice/least preferred; not well-anchored and rolls easily; increased risk of puncturing a median cutaneous nerve branch or the brachial artery; not recommended unless no other vein in either arm is more prominent

Answer 5

Basilic vein

Question 6

Types of blood specimens:

Answer 6

1. serum
2. plasma
3. whole blood

Question 7

Normally a clear, pale yellow fluid; separated from clotted blood by centrifugation (approx. 10 minutes at an RCF of 1,000 to 2,000g)

Answer 7

Serum

Question 8

Normally a clear to slightly hazy, pale yellow fluid; separates from the cells when blood in an anticoagulant tube is centrifuged; contains fibrinogen

Answer 8

Plasma

Question 9

Contains both cells and plasma; must be collected in an anticoagulant tube to keep it from clotting; used for most hematology tests and many point-of-care tests (POCTs), especially in acute care and stat situations

Answer 9

Whole blood

Question 10

Methods of venipuncture:

Answer 10

1. Evacuated tube system (ETS)
2. Needle and syringe
3. Butterfly set

Question 11

preferred method because blood is collected directly from the vein into a tube, minimizing the risk of specimen contamination and exposure to the blood

Answer 11

Evacuated tube system (ETS)

Question 12

Discouraged by CLSI due to safety and specimen quality issues; sometimes used on small, fragile, or damaged veins

Answer 12

Needle and syringe

Question 13

Can be used with the ETS or a syringe; often used to draw blood from infants and children, hand veins, and in other difficult-draw situations

Answer 13

Butterfly set

Question 14

Venipuncture equipment that restricts venous flow but not arterial flow:

Answer 14

Tourniquet

Question 15

Tourniquet rule:

Answer 15

Must not be left on longer than 1 minute

Question 16

Tourniquet dimensions:

Answer 16

1 inch wide x 15 inch long

Question 17

considered standard needle gauge (adult) for routine venipuncture:

Answer 17

21 gauge

Question 18

Three basic components of ETS:

Answer 18

1. Multisample needle
2. Tube holder
3. Evacuated tubes

Question 19

usual needle gauge for butterfly system

Answer 19

23 gauge - most commonly used for phlebotomy; used among children

Question 20

A handheld medical device that helps medical staff visualize veins before phlebotomy. The device emits infrared light and is held about 7 inches over the potential phlebotomy site

Answer 20

AccuVein

Question 21

Order of Draw:

Answer 21

1. Sterile tube (blood culture)
2. Coagulation tube (blue top)
3. Serum tube with or without clot activator, with or without gel (Red top)
4. Heparin tube with or without get separator (green top)
5. EDTA tube with or without get separator (lavender top, pearl top)
6. Glycolytic inhibitor tube (gray top)

Mnemonic:
Stop - Sterile
Light - Light blue
Red - Red
Stay - SST (serum separator tube)
Put - PST (plasma separator tube)
Green - Green
Light - Lavender
Go! - Gray

Question 22

Lengths of lancet should be:

Answer 22

less than 2.0 mm to avoid penetrating the bone

Question 23

Sites for capillary puncture:

Answer 23

1. Palmar surface of 3rd and 4th fingers
2. Lateral plantar heel surface (newborns)
3. Earlobes

Question 24

Capillary order of draw (CLSI)

Answer 24

• EDTA specimens
• Other additive specimens
• Serum specimens

Question 25

What equipment is used for drawing blood for blood gas analysis:

Answer 25

Syringe syringe are used instead of evacuated tubes because of the pressure in an arterial blood vessel

Question 26

Preferred anticoagulant for blood gas analysis:

Answer 26

Heparin/ 0.05 heparin/mL of blood

Question 27

Primary arterial sites:

Answer 27

Radial artery Brachial artery Femoral artery

Question 28

It is done before collecting arterial blood from radial artery; to determine whether the ulnar artery can provide collateral circulation to the hand after the radial artery puncture.

Answer 28

Modified Allen test

Question 29

Diurnal variations Increase in AM: Increase in PM:

Answer 29

Diurnal variations Increase in AM: ACTH, Cortisol, Fe, Aldosterone Increase in PM: ACP, Growth hormone, PTH, TSH

Question 30

Recent food ingestion increase: decrease:

Answer 30

Recent food ingestion increase: Glucose, insulin, triglycerides, gastrin, ionized calcium decrease: Chloride, phosphorus, potassium, amylase, ALP

Question 31

Stress increase:

Answer 31

increase: ACTH, cortisol, catecholamines, prolactin

Question 32

First hormone to increase during stress:

Answer 32

Catecholamines

Question 33

Parameters that require fasting:

Answer 33

FBS GTT Triglycerides Lipid panel Gastrin Insulin Aldosterone/Renin

Question 34

Parameters that increases in Hemolysis:

Answer 34

Potassium PO4 Fe Magnesium ALT AST LD ALP Catecholamines CK (marked hemolysis)

Question 35

Anaerobic and require ICE slurry (immediate cooling)

Answer 35

Lactic acid Ammonia Blood gas (if not cooled = decrease pH and pO2) "LAB"

Question 36

Routine specimens ideally delivered to the laboratory wihthin:

Answer 36

45 minutes of collection

Question 37

Routine specimens are centrifuged within:

Answer 37

1 hour of arrival if serum or plasma is needed

Question 38

Maximum time limit for serum or plasma separation is:

Answer 38

2 hours after collection (CLSI standard)

Question 39

a medical term meaning "immediately"; collected and analyzed immediately; given the highest priority and are usually ordered from the emergency department and critical care

Answer 39

Stat collections

Question 40

Analytical patient-testing activities provided within the institution, but performed outside the physical facilities of the clinical laboratories; Laboratory testing that is performed outside the central or core laboratory and generally at the site of clinical care or close to the patient

Answer 40

Point-of-Care testing (POCT)

Question 41

The highest-volume POC test in most health care institutions

Answer 41

POC glucose

Question 42

Most common POCT specimen:

Answer 42

Capillary blood