What is radial intraosseous (IO) access?

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Last updated: May 25, 2025View editorial policy

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From the Guidelines

Radial IO access is not the preferred site for intraosseous access, instead, the proximal humerus or proximal tibia are recommended as primary sites, with the distal tibia as an alternative. The use of intraosseous access is a rapid, safe, effective, and acceptable route for vascular access in emergency situations, including cardiac arrest 1. According to the Association of Anaesthetists of Great Britain and Ireland, intra-osseous access is useful in emergencies when intravenous access is difficult, and is faster than central access 1.

Key Considerations

  • The tibia and the humerus are preferred sites for intraosseous access, with the insertion site for the tibia being 2 cm distal to the tibial tuberosity and 1 cm medial to the tibial plateau 1.
  • Success of intraosseous access is evident by aspiration of bone marrow, saline flush with no extravasation, support of the needle by the bone cortex, and infusion under gravity alone 1.
  • Complications of intraosseous access include fracture, extravasation, osteomyelitis, infection, compartment syndrome, growth plate injury, and pressure necrosis of the skin 1.
  • Devices should be removed as soon as suitable IV access is achieved, ideally within 24 hours of placement 1.

Recommendations

  • Use the proximal humerus or proximal tibia as primary sites for intraosseous access, with the distal tibia as an alternative.
  • Use an EZ-IO or similar powered device with a 15G or 25mm needle for most patients (45mm for larger patients).
  • Confirm placement by aspirating bone marrow and testing for stability, then flush with 10mL saline followed by medications or fluids as needed.
  • Monitor the site regularly while in use to reduce the risk of complications.

From the Research

Radial IO

  • Radial intraosseous (IO) access is a reliable alternative to intravenous vascular access, especially in emergency situations when intravenous access is difficult or impossible 2.
  • The use of ultrasound guidance is recommended for radial arterial access, as it has been shown to increase first-pass success rates, reduce the time to successful cannulation, and reduce the risk of complications compared to landmark-based techniques 3.
  • Intraosseous infusion is an effective and safe technique that increases patient survival, and it is crucial that healthcare professionals know how to handle different intraosseous devices in situations where immediate peripheral venous access is not possible 4.
  • The EZ-IO needle driver is an efficient alternative for establishing immediate out-of-hospital vascular access, with a high success rate of insertion and minimal complications 2.
  • However, significant pain upon intramedullary infusion was observed in the majority of responsive patients, highlighting the need for proper pain management during intraosseous line insertion 2.
  • Primary healthcare physicians should acquire the skill of intraosseous line insertion, as it is a lifesaving procedure that provides early rapid access to the vascular system in emergencies 5.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Intraosseous line insertion for the primary health care physician.

South African family practice : official journal of the South African Academy of Family Practice/Primary Care, 2023

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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