Steps

Rationale/Points of Emphasis

1 Proceed with catheter placement as described in Chapter 45 .

An arterial catheter is used to monitor and obtain hemodynamic readings for evaluation of blood pressure (systolic, diastolic, and mean) for cardiovascular monitoring of acutely ill children.

2 Review baseline data—vital signs, level of consciousness, hemodynamic stability—of child.

Assists to identify any acute changes in child during and after the procedure.

Prompt treatment of critical illness is associated with improved chances of survival.

3 If indicated by anatomical location of the arterial catheter, immobilize the extremity where the catheter is inserted by using an armboard or limb restraint. Keep the catheter site visible at all times—do not allow linens to cover site.

Holds arterial catheter in place, helps prevent dislodgment of catheter with child movement, and helps prevent arterial catheter from lacerating internal vessel. The risk of an intra-arterial line becoming dislodged leads to a high risk for exsanguination (in the pediatric/neonatal population, this can take place in a very short period of time and can be fatal).

4 Observe the IV pressure bag and ensure inflation to 300 mm Hg on the pressure bag manometer. Reinflate as necessary. If using an infusion pump, validate the flow rate.

Pressure is required for most flush devices to avoid blood backup and to maintain catheter patency. When inflated to 300 mm Hg of pressure, most flush devices deliver 3 mL/hour of IV fluid. The amount of pressure in the infusion device decreases naturally over time because fluid infuses and must be reinflated periodically.

Children who are severely fluid restricted may require use of a syringe pump or microinfusion device to limit the flow of infused fluid. Flow rate amounts are variable and are dictated by patient size and fluid restriction. Tubing is available that is capable of delivering as little as 0.3 mL/hour.

5 Maintain the position of the transducer stopcock on the IV pole or other holding device, with the child’s right atrium, usually at the fourth intercostal space, midaxillary line (phlebostatic axis).

Ensures accuracy of readings by eliminating hydrostatic forces on the transducer (see Chapter 45 , Fig. 45-1).

6 Zero-balance and calibrate the transducer at the start of each shift by turning the stopcock above the transducer off to the patient line and then pressing the 0 (zero) button on the bedside monitor. Follow manufacturer’s instructions.

Pressing the zero button negates the effects of atmospheric pressure, so that the pressure values reflect only that of the patient.

7 Return transducer stopcock back to monitoring position to resume pressure monitoring. Check that the stopcock above the transducer is now open to monitoring.

Pressure monitoring cannot occur if stopcocks are not in the correct position. (Refer to manufacturer’s system instructions for correct stopcock placement.)

8 Arterial blood pressure waveform and mean reading should be continuously monitored and interpreted, along with electrocardiogram (ECG) and other monitor tracings.

A continuous waveform and readout is provided at the child’s bedside monitor along with ECG and other monitor tracings, which allows the nurse to identify any acute or gradual changes and make clinical decisions based on these changes.

Appropriate pressure alarms should be on at all times during monitoring to provide an alert to clinical changes in the child’s condition or equipment malfunction.

9a Frequently assess that the pressure bag is inflated to 300 mm Hg.

Appropriate inflation is necessary for proper function of flush device to deliver 3 mL/hour of fluid and to prevent blood from back-flowing into the catheter.

9b At least once per shift, ensure that there is flush solution in IV bag.

Continuous flush is necessary to keep the arterial catheter from clotting off.

9c Continuously observe arterial waveform quality as viewed from monitor.

Ensures accuracy of pressure waveform and detection of changes in child’s hemodynamic status. A normal waveform has a peak systole, clear dicrotic notch, and end diastole.

10 Troubleshoot the arterial catheter waveform as problems occur and notify healthcare prescriber as appropriate. If the waveform suddenly becomes dampened:

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  Check the child.

  
  
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  Check the arterial line insertion site for catheter position.

  
  
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  Attempt to aspirate and flush the catheter.

A sudden hypotensive episode can look like a dampened waveform on the monitor and can be potentially life-threatening.

For peripheral insertion of a catheter, movement of the child can cause kinking or dislodgment, resulting in dampened waveform.

Clots can form at the catheter tip and obstruct flow, causing a dampened waveform or emboli. Aspirate to pull back and dislodge the potential clot formation.