What are the steps to troubleshoot an arterial line issue?

Arterial Line Troubleshooting Protocol

When troubleshooting an arterial line issue, follow a systematic approach focusing on the flush solution, sampling technique, and system integrity to prevent dangerous errors that could lead to patient harm.

Initial Assessment

• Verify that only sodium chloride 0.9% (with or without heparin) is being used as the arterial line flush solution to prevent dangerous sampling errors 1
• Check that the flush solution bag is correctly labeled and positioned in a pressurizing device with a transparent front panel 1
• Ensure the arterial line system is clearly identifiable with appropriate labels and color differentiation from other lines 1
• Inspect the entire system for kinks, disconnections, air bubbles, or blood clots that may affect pressure readings or sampling 1

Waveform Issues

• For dampened waveform:

  • Check for air bubbles in the line and flush thoroughly to remove them 1
  • Inspect for blood clots in the catheter and consider gentle aspiration followed by flushing 1
  • Verify the position of the catheter (may be against vessel wall) 2
  • Ensure the transducer is at the correct level (phlebostatic axis) 1

• For absent waveform:

  • Confirm the arterial catheter is still in the artery and hasn't dislodged 2
  • Check all connections between catheter, tubing, and monitoring system 1
  • Ensure the pressure bag is inflated to 300 mmHg 1
  • Consider catheter occlusion or vessel spasm as potential causes 2

Blood Sampling Problems

• When using an arterial line for blood sampling:

  • Use 'closed' arterial line sampling systems when possible to avoid sample contamination 1
  • With 'open' systems, minimize contamination by making the dead space volume between sampling port and arterial lumen as small as practicable 1
  • Ensure the syringe for dead space removal is readily distinguishable from the sampling syringe 1
  • Throughout sampling, prevent flush solution from entering the dead space, sample, or any three-way tap at the sampling site 1

• For unexpected laboratory results:

  • Check for possible sample contamination with flush solution 3
  • If unexpected high glucose readings are obtained, verify the flush solution is not glucose-containing 3
  • Draw a confirmatory sample from an alternative site if contamination cannot be ruled out 3

Site-Related Issues

• For site complications:
  • Assess for signs of infection, hematoma, or ischemia at the insertion site 2
  • Consider femoral placement if radial site is failing, as femoral arterial lines have significantly lower failure rates (5.4% vs 25.6-30.7%) 2
  • Monitor for signs of distal ischemia by checking capillary refill, color, and temperature of the extremity 2

System Maintenance

• Independently double-check the flush infusion bag at least once during each nursing shift 1
• Double-check the flush bag whenever nursing care of the patient is handed over 1
• Include removal of the flush bag from its pressurizing device during checks 1
• Ensure the system is properly zeroed and calibrated regularly 1

Common Pitfalls and Prevention

• Never use glucose-containing solutions as arterial line flush, as even minimal contamination can lead to dangerous sampling errors 3, 1
• Be cautious with sodium chloride 0.9% with glucose 5%, which can be easily confused with plain sodium chloride 0.9% 3
• Watch for erratic or highly varying sequential test results, which should heighten suspicion of blood sample contamination 3
• Be aware that even with proper technique using 5× dead space removal, significant glucose contamination can occur with glucose-containing flush solutions 3
• Consider that radial arterial lines fail more frequently than femoral lines, with failures occurring sooner in radial sites 2