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196 Section V ■ Vascular Access

2. Cutdown or open surgical technique

a. Advantages

(1) Allows for insertion of larger silicone catheter

(3 or 4.2 French [Fr])

(2) The catheters can be tunneled under the skin

away from the venotomy site, so they can remain

in place longer with a lower risk of infection.

b. Disadvantages

(1) Requires general anesthesia or IV sedation

(2) Requires surgical incision

(3) Vein is often ligated, so it cannot be reused in

the future.

(4) Potential for injury to adjacent anatomical structures

(5) Increased potential for wound infection

(6) An operating room is the ideal setting for the

procedure, so risks of transport of critically ill

neonates need to be taken into consideration.

G. Types of Central Venous Catheters

1. Catheter materials: See Table 32.2.

2. Types of catheters

a. Percutaneous (PICC) catheters/introducers

PICC catheters and kits are available commercially. PICCs are generally made of silicone or polyurethane. Sizes include 1.2, 1.9, 2, and 3 Fr. Larger

sizes are generally not used in the neonatal population. Most catheters are single-lumen. Double-lumen

catheters can decrease the need for maintaining concurrent IV access when more than one site is

required. PICC introducers/needles are available in

20 to 28 gauge. Choice will depend on the size of the

vein to be cannulated.

b. Surgically placed central venous catheters

Surgically placed central venous catheters for

neonates are available in sizes 2.5, 2.7, 3, 4.2, and

5 Fr. Catheters are usually silicone or polyurethane,

with tissue in-growth cuffs that adhere to the subcutaneous tract, anchoring the catheter. Recently,

antimicrobial cuffs have become available. Most

catheters are single-lumen, but a few manufacturers

make double-lumen catheters.

Percutaneous Central Venous

Catheterization (See Procedures

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A. Insertion Sites (Fig. 14.1)(Table 32.1)

The veins used, in order of preference are

1. Antecubital veins: Basilic and cephalic veins

2. Saphenous veins

3. Scalp veins: Temporal and posterior auricular veins

4. Axillary vein

5. External jugular vein

Right-sided and basilic veins are preferred because

of the shorter and more direct route to the central vein.

The cephalic vein may be more difficult to thread to

the central position because of narrowing of the vessel

as it enters the deltopectoral groove and the acute angle

at which it joins the subclavian vein. The axillary and

external jugular veins are the last choices because they

are close to arteries and nerves.

B. Insertion Variations

1. Break-away needle (Fig. 32.2): Needle is inserted into

the vein. Next, the catheter is advanced through the

needle. The needle is then retracted, split, and

Table 32.2 Catheter Materials

Type of Catheter Advantages Disadvantages

Silicone Soft, pliable

Lower risk of vessel perforation

Reported to be thromboresistant

May be more difficult to insert percutaneously

Thrombosis reported

Fragile material: Less tolerance to pressure

Poor tensile strength: Can tear or rupture

May be less radio-opaque

Polyurethane Easier to insert percutaneously

Stiffer on insertion but softens within body

Some catheters are more radio-opaque

Tensile strength: More tolerant to pressure

Reported to be thromboresistant

Increased risk of vessel perforation during insertion

Thrombosis reported

Polyethylene Easier to insert

Very high tensile strength

High degree of stiffness may increase vessel perforation during insertion or

throughout catheter dwell

Polyvinyl chloride (PVC) Easier to insert percutaneously

Stiff on insertion but softens within body

May leach plasticizers into body

High incidence of thrombosis