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An N. Massaro

Khodayar Rais-Bahrami

31 Peripheral Arterial Cannulation

Arterial access is often needed in the care of the sick neonate for continuous hemodynamic monitoring and blood

sampling. For various technical or clinical reasons, catheterization of the umbilical artery is not always possible.

Therefore, peripheral arterial cannulation may be required.

As a general rule, the most peripheral available artery

should be used, to reduce the potential sequelae from any

associated vascular compromise or thromboembolic event.

The artery chosen should be large enough to measure blood

pressure without occlusion, have adequate collateral circulation, be at a site with low infection risk, and be in an area

that can be easily monitored and cared for by nursing staff.

Common sites for peripheral arterial cannulation include

the radial, ulnar, dorsalis pedis, and posterior tibial arteries.

Although cannulation of the axillary (1,2) and brachial (3)

arteries have been described, these sites are not recommended because of the limited collateral blood flow and

high potential for ischemic complications. Cannulation of

the temporal artery should likewise be avoided due to

potential adverse neurologic sequelae (4,5).

A. Indications

1. Monitoring of arterial blood pressure

2. Frequent monitoring of blood gases or laboratory tests

(e.g., sick ventilated neonates or extremely lowbirthweight premature infants)

3. When preductal measurement is required (e.g., with

persistent pulmonary hypertension) (right upper

extremity cannulation)

B. Contraindications

1. Bleeding disorder that cannot be corrected

2. Pre-existing evidence of circulatory insufficiency in

limb being used for cannulation

3. Evidence of inadequate collateral flow (i.e., occlusion

of the vessel to be catheterized may compromise perfusion of extremity)

4. Local skin infection

5. Malformation of the extremity being used for cannulation

6. Previous surgery in the area (especially cutdown)

C. Equipment

Sterile

1. Gloves

2. Antiseptic solution (e.g., iodophor, chlorhexidine)

3. 4- × 4-inch gauze squares

4. 0.5 to 0.95 normal saline (NS) with 1 to 2 U/mL heparin

Although hypernatremia has been reported in very

small premature infants who received excess sodium in

flush solution (6), in our experience 0.5 NS has been

used without complications at infusion rates of 0.5 to

1 mL/h. Using heparinized saline has been shown to

maintain line patency longer than hypotonic solutions

such as heparinized 5% dextrose water (7) or unheparinized NS (8).

5. 3- or 5-mL syringe

6. 20-gauge venipuncture needle (if using larger-sized

22-gauge cannula)

7. Appropriate-sized cannula: 22-gauge × 1-inch (2.5-cm),