1. Gloves

2. Alcohol swabs

3. Rubber-tipped clamps or disposable IV tubing clamps

4. Syringe of 0.6 mL of flushing solution

5. Syringe for cleaning line

6. Syringe for blood sample

7. Ice, if necessary for sample preservation

8. Appropriate requisition slips and labels

Technique

1. Wash hands and put on sterile gloves.

2. Form sterile field.

3. Clean the connection site of the stopcock/catheter

using an alcohol swab.

4. Clamp the umbilical catheter.

5. Connect the 3-mL syringe, release the clamp, and

slowly draw back 2 to 3 mL of fluid over 1 minute to

clear the line. Reclamp the catheter. Remove syringe

and place on sterile field. Data published by Davies

et al. (36) indicate that accurate measurements of electrolytes can be obtained after withdrawal of a minimum

of 1.6 mL of blood. However, if blood glucose values

are desired, a minimum of 3 mL from a 3.5-Fr and

4 mL from a 5-Fr catheter must be withdrawn.

6. Attach sampling syringe. Release clamp and draw back

specimen desired. Reclamp the catheter.

7. Reattach the syringe containing the fluid and blood

cleared from the line.

a. Clear the connection of air.

b. Slowly replace the fluid and blood cleared from the

line and remove the syringe.

8. Attach the syringe of flushing solution to the stopcock,

clear air from the connection, and slowly flush the line.

9. Clean the stopcock connection with alcohol.

10. Record on infant’s daily record sheet all blood removed

and volume of flush used.

A study was carried out that looked at cerebral

oxygenation and blood sampling from UAC in high

position in preterm infants (median gestational age

30 weeks). Although the clinical significance is unclear,

the study showed that blood sampling of 2.3 mL

(including flush volumes) through the UAC within

20 seconds resulted in a significantly decreased cerebral oxygenated hemoglobin and tissue oxygenation

index. It also caused an increase in deoxygenated

hemoglobin. This was not seen when the sampling

time was extended to 40 seconds (37).

I. Removal of UAC

Indications

1. No further clinical indication

2. Need for less frequent direct PO2 measurements

3. Sufficient stabilization of blood pressure to allow intermittent monitoring

4. Hypertension

5. Hematuria not due to other recognizable cause

6. Catheter-related sepsis and/or infections with

Staphylococcus aureus, gram-negative bacilli, or Candida

mandate removal of the catheter (38)