Capillary Puncture

Question 1

What is a capillary puncture?

Answer 1

a safe, rapid and efficient means of collecting a blood specimen

Question 2

why are capillary punctures performed?

Answer 2

when only a small amount of blood is needed or when blood must be obtained from infants and children

Question 3

what is the usual puncture sites for adults?

Answer 3

the ring finger on non-dominant hand

Question 4

what is the usual puncture sites for infants?

Answer 4

the lateral portion of the heel pad

Question 5

how is a capillary site prepared?

Answer 5

an alcohol swab is used to clean the puncture site and it is air dryed

Question 6

what is the procedure if circulation seems poor at the selected site?

Answer 6

a patients hand can be gently massaged briefly to enhance circulation

Question 7

why is the first drop of blood wiped away?

Answer 7

the first drop of blood contains interstitial (tissue) fluid which dilutes the blood drop and activates clotting

Question 8

list safety precautions that must be observed when performing a capillary puncture:

Answer 8

1) must use PPE & follow universal precautions
2) plastic or mylar tubes to minimize risk of injury
3) lancets & tubes must be disposed in bio-hazardous sharps container
4) other blood-contained materials should be disposed in bio-hazardous (non-sharps) container

Question 9

why must the blood from a capillary puncture be used quickly?

Answer 9

to prevent clotting

Question 10

list three important aspects of quality assessment in capillary puncture:

Answer 10

follow the correct use of collection equipment, collection procedures and specimen handling.
REMEMBER: must be performed quickly, puncture site shouldn’t be squeezed excessively

Question 11

DEFINE CAPILLARY

Answer 11

a minute blood vessel that connects the smallest arteries to the smallest veins and serves as an oxygen exchange vessel

Question 12

DEFINE CAPILLARY ACTION

Answer 12

the action by which a fluid enters a tube because of the attraction between the fluid and the tube

Question 13

DEFINE CAPILLARY TUBE

Answer 13

a slender glass or plastic tube used for laboratory procedures

Question 14

DEFINE HEPARIN

Answer 14

an anticoagulant used therapeutically to prevent thrombosis; also used as an anticoagulant in certain laboratory procedures

Question 15

DEFINE LANCET

Answer 15

a sterile, sharp-pointed blade used to perform capillary puncture

Question 16

DEFINE LATERAL

Answer 16

toward the side

Question 17

when is a capillary tube with a blue band used?

Answer 17

non-heparinized capillary tubes are used with venous blood that has previously been collected in an anticoagulant

Question 18

when is a capillary tube with a red band used?

Answer 18

contains the anticoagulant heparin, used to prevent clotting of the blood during collection of capillary blood samples