What does warming a site for skin puncture do?

Blood obtained via skin puncture is a mixture of undetermined proportions of blood from arterioles, venules, capillaries, plus interstitial and intracellular fluids. Warming of the puncture site further “arterializes” the blood and increases blood flow.

Collect the blood sample in a collection device appropriate for the test to be performed. NOTE: Warming the skinpuncture site with a warm moist cloth, or a heel warming device, for 3 minutes can increase blood flow through the site. Allow the heel to air dry.

Secondly, what does squeezing the skin puncture site do to the specimen? Wipe away the first drop of blood because it may be contaminated with tissue fluid or debris (sloughing skin). Avoid squeezing the finger or heel too tightly because this dilutes the specimen with tissue fluid (plasma) and increases the probability of haemolysis (60).

In this way, what is the purpose of warming the site for capillary puncture?

Warming the site will increase the Page 4 blood flow, making it easier to collect the specimen. As the specimen is being collected, be sure the blood is not running or smearing on the skin surface. Large round drops of blood provide easier collection.

What areas on an infant are suitable for skin puncture?

The heel of the foot is the preferred site for dermal puncture and capillary blood collection for infants less than 12 months old. CAUTION: In premature infants, the bone may be as close as 2.0 mm under the skin of the plantar surface of the heel.

Why is the first drop of blood wiped away?

Wipe away the first drop of blood (which tends to contain excess tissue fluid). pressure to the surrounding tissue until another drop of blood appears. Avoid “milking”. The drop of blood must be big enough to fill the strip completely.

What is the difference between venipuncture and dermal puncture?

In some situations, the phlebotomist will make the decision if a blood specimen will be obtained by dermal puncture or venipuncture. A dermal puncture requires less precision, therefore it is less critical for the patient to be still or immobilized.

What is the ideal depth of skin puncture?

Heel stick The capillary bed on an infant’s heel is about 0.35-1.6 mm beneath the skin. The recommended depth of incision is about 2 mm, anything deeper will present the risk of nerve or bone damage and should be avoided.

How Deep is a skin puncture?

Perform the skin puncture. Dispose of the puncture device in a Sharps container. For infants, the heel puncture should be no deeper than 2.0 mm. Wipe the first drop of blood away with dry gauze. Grasp the foot or finger between the thumb and first finger and apply gentle pressure.

Why do we need arterioles?

Arterioles face a smaller blood pressure, meaning they don’t need to be as elastic. Arterioles account for most of the resistance in the pulmonary circulation because they are more rigid than larger arteries. Furthermore, the capillaries branch off of arterioles and are made from a single cell layer.

What is skin puncture?

Definition: Puncture of the skin with a needle or introducer to provide an entry site for arterial access.

Which are the most ideal areas for capillary puncture on the hand?

The puncture must be on the palm-up surface of the distal segment (fingertip) of the middle or ring finger (Figure 3, a). Recommendations for finger pricking. The puncture must be on the palm-up surface of the distal segment (fingertip) of the middle or ring finger (a).

Which finger is the best choice for a capillary puncture for blood collection?

Finger – Usually the third or fourth finger is preferred in adults and children. The thumb has a pulse and is likely to bleed excessively. The index finger can be calloused or sensitive and the little finger does not have enough tissue to prevent hitting the bone with the lancet.

How do you perform a capillary puncture?

FINGER STICK Position the patient so that the hand is easily accessible. Cleanse the fingertip of the 3rd (middle) or 4th (ring) finger with an alcohol prep. Using a sterile lancet, puncture the fingertip in the fleshy part of the finger, slightly to the side. Wipe away the first drop of blood with a sterile 2×2 gauze.

What is the order of draw for capillary puncture?

CLSI established the order of draw for capillary specimens to be as follows: First — EDTA tubes; Second — other additive tubes; Third — non-additive tubes.

What is a capillary puncture quizlet?

The superficial puncture of the skin to obtain a small amount of capillary blood. It determines the volume percentage of RBC’s in whole blood.

Which color top Microcollection container would be used to collect a specimen for a CBC?


How long should you wait before centrifuging a serum blood sample tube?

Allow the tube to clot for 20-30 minutes in a vertical position. Do not centrifuge immediately after drawing the blood. Do not allow the blood to clot with the tube in a horizontal position. Do not allow the tube to stand more than one hour before centrifuging.