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Question 1

———— specimens are a mixtures of arterial, venous, and capillary blood along with interstitial fluid and intracellular fluid from surrounding tissues.

Answer 1

Capillary

Question 2

These are fluid in the tissue spaces between the cells

Answer 2

Interstitial fluid

Question 3

These are fluid within the cells

Answer 3

Intracellular fluid

Question 4

What kind or type of blood enters the capillaries under pressure?

Answer 4

Arterial blood

Question 5

Capillary blood contains a ——– (higher, lower) proportion of arterial blood than venous blood

Answer 5

higher

Question 6

Warming causes ———- (increases, decreases) arterial flow into the area

Answer 6

increases

Question 7

Capillary Puncture Equipment

Answer 7

1. Lancets/incision devices
2. Microcollection containers
3. Microhematocrit tubes and sealants:
   
   • Red or green band: Heparinated tube - Blue band: Non-additive tube

Question 8

Capillary puncture can be an appropriate choice for adults and older children under what circumstances?

Answer 8

• Available veins are fragile or must be saved for other procedures such as chemotherapy
• Several unsuccessful venipunctures have been performed and the requested test can be collected by capillary puncture
• The patient has thrombotic or clot-forming tendencies
• The patient is apprehensive or has an intense fear of needles
• There are no accessible veins (e.g., the patient has IV’s in both arms or the only accepted sites are in scarred or burned areas).
• To obtain blood for POCT procedures such as glucose monitoring

Question 9

Capillary puncture is the preferred method of obtaining blood from infants and very young children for what reasons:

Answer 9

• Infants have a small blood volume; removing quantities of blood typical of venipuncture or arterial puncture can lead to anemia. According to studies, for every 10 mL of blood removed, as much as 4 mg of iron is also removed
• Large quantities removed rapidly can cause cardiac arrest. Life is threatened if more than 10% of a patient’s blood volume is removed at once or over a short period.
• Obtaining blood from infants and children by venipuncture is difficult and may damage veins and surrounding tissues
• Puncturing deep veins can result in hemorrhage, venous thrombosis, infection and gangrene
• An infant or child can be injured by the restraining method used while performing a venipuncture
• Capillary blood is the preferred specimen for some tests, such as newborn screening tests

Question 10

Concentration of glucose is normally ——— (higher, lower) in capillary blood specimens

Answer 10

higher

Question 11

Total ——–, ———-, and ———-, concentrations are lower in capillary blood specimen

Answer 11

protein, calcium, and potassium

Question 12

These values are normally lower in properly collected skin puncture specimens, levels may be falsely elevated if there is tissue fluid contamination or hemolysis of the specimen

Answer 12

Potassium

Question 13

What are some tests that cannot be collected by capillary puncture

Answer 13

1. erythrocyte sedimentation rate methods
2. coagulation studies that require plasma specimens
3. blood cultures
4. tests that require large volumes of serum or plasma

Question 14

What is usually the preferred site for capillary testing in an adult patient?

Answer 14

finger

Question 15

What are only used in pediatric and neonatal patients?

Answer 15

sides of the heel

Question 16

What are sometimes used in mass screening or research studies?

Answer 16

Ear lobes

Question 17

What are some basis for selection of a site for capillary sampling in a pediatric patient?

Answer 17

Age and Weight of the patient

Question 18

Heel Puncture Precautions

Do not puncture any deeper than ——–.

Answer 18

2.0 mm

Question 19

Heel Puncture Precautions

Do not puncture in the —– and any areas of the foot other than the heel. Arteries, nerves, tendons, and cartilage in these areas can be injured

Answer 19

arch

Question 20

Heel Puncture Precautions

Do not puncture the ——– (posterior, anterior) curvature of the heel. The bone can be as little as —— deep in this area.

Answer 20

posterior; 1mm

Question 21

Puncturing the skin releases tissue —–, which activates the coagulation process in blood drops.

Answer 21

Thromboplastin

Question 22

Why are hematology specimens collected first?

Answer 22

They are collected first because they are the most affected by the clotting process

Question 23

What specimens are collected last?

Answer 23

Serum

Question 24

Why are serum specimens collected last?

Answer 24

They are collected last because they are supposed to clot

Question 25

CLSI order of draw for capillary specimens:

Answer 25

1. Blood gas specimens (CBG’s)
2. EDTA specimens
3. Other additive specimens
4. Serum specimens