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Arterial Line

NEJM Video Guide


  • Continuous, accurate hemodynamic monitoring (pts requiring vasopressor titration, pts whose BP accuracy is in question)

  • Need for frequent ABGs


  • Abnormal Allen's test, thrombosis of selected site, distorted anatomy at selected site (known prior fistulas, grafts, malformations), severe PAD at selected site, Raynaud's of selected limb
  • Bruising, pain, damage to adjacent structures, infection, bleeding (possible extension to RP bleed with femoral placement), hematoma formation, vascular complications (dissection, AV fistula, pseudoaneurysm), thrombosis, rarely distal ischemia

Pre-procedural considerations

  • Bleeding risk guidelines: no definitive guidelines (some suggest plts > 50K, INR < 3, PTT < 100)

  • Palpate of artery of interest to best understand anatomy and surrounding structures

  • Allen Test if placing radial artery access: goal to assess collateral ulnar blood flow to avoid ischemia. Compress both radial and ulnar artery 10-15 sec to allow blanching of palm, then release ulnar artery to assess re-perfusion. If blanching quickly resolves, ulnar artery will allow distal perfusion

  • If attempting radial access, ensure wrist is adequately extended; use towel roll under wrist and tape hand to bed or table

  • Discuss with fellow prior to brachial a-line placement

  • Ask RN to prepare tubing and waveform monitoring prior to time-out

Procedural considerations

  • Types of Kits

    • Arrow kit: all-in-one device that has arterial catheter over introducer needle

    • A-line kit: individual introducer needle, guidewires, and sutures; multiple steps

    • Micropuncture kit: atraumatic guidewire, microcatheter and introducer sheath

  • Reconfirm location with US after lidocaine

  • Ensure arterial access (pulsatile flow of bright red blood)

Post- procedural considerations

  • Immediately connect pressure tubing to catheter while maintaining sterile technique

  • Observe monitor for arterial waveform to verify appropriate placement

  • If persistent bleeding, hold pressure for 15 mins