TRIPASS XR تري باس

 

89

Ashish O. Gupta

14 Venipuncture

A. Indications

1. Blood sampling

a. Routine laboratory tests, particularly if the volume

of blood required is larger than can be obtained by

capillary sampling.

b. Blood culture

c. Central hematocrit

d. Preferred (over capillary sample) for certain studies

(1,2)

(1) Ammonia, lactate or pyruvate level (arterial

optimal)

(2) Drug levels

(3) Cross-matching blood

(4) Hemoglobin/hematocrit

(5) Karyotype

(6) Coagulation studies

2. Administration of medications

B. Contraindications

1. Use of deep vein in presence of coagulation defect

2. Local infection and/or inflammation at puncture site

3. Femoral or internal jugular vein (see G)

4. External jugular vein in infants with respiratory distress, intracranial hemorrhage, or raised intracranial

pressure

C. Precautions

1. Observe universal precautions.

2. When sampling from neck veins, place infant in headdown position to avoid cranial air embolus. Do not use

neck veins in infants with intracranial bleeding or

increased intracranial pressure.

3. Remove tourniquet before removing needle (to minimize hematoma formation).

4. Apply local pressure with dry gauze to produce hemostasis (usually 2 to 3 minutes).

5. Avoid using alcohol swab to apply local pressure (painful, impairs hemostasis).

D. Special Considerations for Neonates

1. Conserve sites to preserve limited venous access by

using distal sites first whenever possible.

2. Use small needle or scalp vein butterfly. A 23-gauge

needle is the best. Hemolysis or clotting may occur

with a 25-gauge or smaller needle.

3. Choice of veins in order of preference (Fig. 14.1)

a. Basilic, cephalic, or cubital veins in the antecubital

fossa

b. Greater saphenous vein at the ankle

c. Dorsum of hands

d. Dorsum of feet

e. Vein in center of the volar aspect of the wrist

f. Proximal greater saphenous vein

g. Scalp

h. Neck

4. Pain control

a. Lidocaine–prilocaine topical anesthetic cream

applied 30 minutes prior to procedure, if time allows

(3,4).

b. Oral sucrose solution (12% to 25%) provides quick

and effective pain control for venipuncture (4,5).

c. Heel lancing can be more painful and require more

punctures than venipuncture in infants (3,6).

E. Equipment

1. Gloves

2. A 23-gauge venipuncture needle (Fig. 14.2).

3. Syringe with volume just larger than sample to be

drawn

4. Alcohol swabs

5. Gauze pads

6. Appropriate containers for specimens

7. For blood culture

a. Povidone–iodine solution preparation (three swabs)

b. Sterile gloves

c. Blood culture bottle(s)

d. Transfer needle

8. Tourniquet or sphygmomanometer cuff

90 Section III ■ Blood Sampling

A

B C

Fig. 14.1. The superficial venous system in the neonate.

Chapter 14 ■ Venipuncture 91

F. Technique

General Venipuncture

1. Locate the appropriate vessel. Use transillumination if

necessary (see Chapter 13). Warm extremity with heel

warmer or warm washcloth if circulation is poor.

2. Apply anesthetic cream if time permits, and/or administer sucrose solution if possible.

3. Restrain infant appropriately.

4. Prepare area with antiseptic (see Chapter 5).

5. Occlude vein proximally using either

a. Blood pressure cuff inflated to level between systolic

and diastolic pressure

b. Rubber band (loop two bands together, tied as in

Fig. 14.3)

Fig. 14.2. Safety-engineered needles for venipuncture.

C

A B

Fig. 14.3. Correct application of a tourniquet for quick

release.