Arterial Line Indications and Placement
Arterial lines are recommended for critically ill patients requiring continuous blood pressure monitoring and frequent blood sampling, and should be placed using ultrasound-guided Seldinger technique with polyurethane catheters, preferably in the radial artery for most patients.
Indications for Arterial Line Placement
When to place an arterial line:
Frequent blood sampling needs - Arterial lines are the method of choice for frequent blood analysis in adult critical care areas, reducing the need for repeated venipunctures and preventing contamination errors 1, 2
Continuous hemodynamic monitoring - Required for critically ill patients needing beat-to-beat blood pressure monitoring, particularly those on vasopressor support or with hemodynamic instability 1
High-risk infectious disease management - For severely ill patients with highly pathogenic infectious diseases, arterial lines allow safe serial blood sampling without repeated needle-stick procedures, reducing exposure risk to healthcare workers 1
Reduction of needle-stick injuries - Routinely secured arterial line access minimizes the need for repeated needle-based procedures in patients requiring frequent blood draws 1
Optimal Placement Technique
Ultrasound guidance is superior to palpation:
Ultrasound-guided placement is significantly faster (171 seconds vs 244 seconds), requires fewer attempts (1.78 vs 2.48), and has higher success rates (96% vs 90%) compared to traditional blind palpation 3
The Seldinger technique (using a catheter with separate or integral guide wire) has significantly lower failure rates than direct puncture technique 4
Use polyurethane catheters rather than Teflon, as they are significantly less likely to block and require re-insertion 4
Site Selection
Radial vs femoral artery considerations:
Femoral arterial lines have substantially lower failure rates than radial lines (5.4% vs 26-31% failure rate), with an absolute risk reduction of 20.2% 5
Femoral lines fail less often and last longer than radial lines, preventing one line failure for every fourth line placed 5
Infection was not a significant cause of removal in femoral lines despite traditional concerns 5
However, radial artery remains the most common first-choice site in clinical practice, with femoral reserved for difficult access or when radial is contraindicated 4, 6
Critical Safety Requirements for Arterial Line Management
Flush solution protocols (preventing fatal errors):
Only sodium chloride 0.9% (with or without heparin) should be used as arterial line flush solution - never use glucose-containing solutions 1, 2, 7
Glucose-containing flush solutions have caused fatal neuroglycopenic brain injury through sample contamination leading to falsely elevated glucose readings and inappropriate insulin administration 1
Independently double-check the flush solution with a second practitioner before setup and at least once per nursing shift 2, 8
Store sodium chloride 0.9% bags away from other IV fluids in designated receptacles to prevent mix-ups 2
Blood sampling technique:
Use closed arterial line sampling systems whenever possible to minimize contamination with flush solution 2, 8
Minimize dead space volume between sampling port and arterial lumen 2
Arterial catheters should be the first-choice sampling site for all laboratory tests in critically ill patients with invasive monitoring 8
Common Pitfalls to Avoid
Never assume glucose readings from arterial lines are accurate without verifying the flush solution - even minimal contamination can produce falsely elevated values 2, 8, 7
Avoid direct puncture technique in favor of Seldinger approach to reduce failure rates and procedure time 4
Do not use Teflon catheters when polyurethane options are available, as they block more frequently 4
Be aware that blood-conserving arterial line systems may have lower resonant frequencies and could overestimate systolic blood pressure in patients with high heart rates 9
Ensure all staff involved in arterial line insertion, management, or sampling are appropriately trained and competent 2