SELF/Intraosseous Access

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By the end of this module, learners will develop the knowledge and practical skills necessary to safely establish intraosseous (IO) access. This includes identifying appropriate anatomical sites, performing correct needle insertion, confirming proper placement, and securing the device. Emphasis will be placed on application across varied clinical environments, including prehospital care, the emergency department, hospital wards, and the operating room.

Self-assessment

Please complete the following: Quiz

• Identify the indications and contraindications for IO access and explain their clinical significance.
• Describe the essential elements of informed consent for IO insertion, including risks, benefits, alternatives, and the principle of implied consent in emergencies.
• List the equipment required for IO access and explain the steps of preparation to ensure safe and timely insertion.
• Identify the anatomical landmarks for common IO sites and explain the sequence of insertion and placement confirmation.
• Recognize the complications of IO access and describe the principles of aftercare and transition to IV or central venous access.
• List the required elements of documentation and explain their importance for patient safety and medico-legal purposes.

An intraosseous (IO) line is a device inserted into the bone marrow cavity to provide rapid access to the circulation, used when intravenous (IV) access cannot be obtained. This is most often the case in cardiac arrest, profound hemorrhagic shock, septic shock, and major trauma with peripheral vascular collapse. Nurses should recognize the signs that require urgent initiation of IO access:

• tachycardia with weak peripheral pulses
• delayed capillary refill beyond 3 seconds
• cold clammy extremities
• progressively declining blood pressure

In children, an inability to secure IV access after three attempts or within 90 seconds is considered sufficient justification to proceed with IO placement.

Contraindications must be assessed before attempting placement. Absolute contraindications include fracture of the chosen bone, cellulitis or burns over the insertion site, and the presence of orthopedic prostheses or hardware at that site. Relative contraindications include conditions that reduce bone integrity, such as osteogenesis imperfecta or advanced osteoporosis, and recent IO placement in the same bone within 24–48 hours. Attempting IO placement in a fractured tibia, for instance, risks fluid leakage into surrounding tissues, ineffective resuscitation, and compartment syndrome.

When contraindications exist, alternative routes must be anticipated. Central venous catheterization can provide reliable access but requires technical expertise and more time. Surgical cutdown may be considered in extreme cases but is invasive and time-consuming. The nurse’s role is to prepare IO equipment promptly while also ensuring that central line trays or cutdown kits are available if the team determines IO placement is not appropriate.

Nurses contribute directly to decision-making by examining the proposed insertion limb for trauma, infection, scarring, or deformity. For example, in trauma patients, palpating the tibia for crepitus or abnormal angulation can reveal a fracture that contraindicates its use. This assessment should be communicated immediately to the team so that an alternate site, such as the proximal humerus or contralateral tibia, can be selected without delay.

Informed consent for IO access is often obtained under urgent or emergent conditions, where time may be limited. When the patient is conscious, the nurse should explain that the procedure involves placing a special needle into the bone marrow cavity to allow fluids and medications to reach the bloodstream rapidly. It should be made clear that this access is temporary, typically used for less than 24 hours, and will be replaced by IV or central venous access once the patient is stable.

Patients or guardians should be informed of the risks in direct, understandable terms. These include pain during saline flushing, local infection at the insertion site, leakage of fluid into soft tissue, and rare but serious complications such as osteomyelitis (bone infection that can develop if organisms are introduced during insertion) or compartment syndrome (caused by extravasated fluid raising pressure in a closed muscle compartment, impairing blood flow and tissue viability). Nurses should be prepared to explain that the procedure can be painful, particularly during the initial flush, and that discomfort can be reduced with a slow flush and, when feasible, analgesia.

Alternatives should be mentioned, even if briefly. Central venous catheterization is slower and carries its own risks, such as pneumothorax or arterial puncture. Surgical venous cutdown is invasive and rarely performed outside of major trauma surgery. The explanation should emphasize that IO is chosen because it is the fastest, most effective option to save the patient’s life when IV access cannot be obtained quickly.

If the patient is unconscious or unable to consent, implied consent applies under emergency doctrine. The nurse should document the emergency nature of the procedure, the inability to obtain consent, and whether family members were informed afterward - this documentation protects both the care team and the patient’s rights during emergencies.

Comprehension Quiz

Please complete the following: Clinical Foundations Quiz

All supplies for IO insertion should be prepared before the attempt begins, organized in the sequence they will be used. Essential items include:

After equipment is assembled, the nurse should confirm needle size and depth markings, prepare the sterile field, and ensure the flush syringe and infusion system are ready for immediate use once insertion is complete.

Sterile preparation is critical. The skin at the intended insertion site must be cleaned with chlorhexidine or povidone-iodine in concentric circles, and the operator must don sterile gloves. The nurse should assist by maintaining a sterile field, handling the IO device without contaminating it, and ensuring the flush syringe and dressing materials are ready for immediate use once the device is placed.

Fluid delivery preparation should occur in parallel. Nurses must prime IV tubing and connect it to a pressure bag or prepare to manually compress the IV bag during infusion, as gravity flow is insufficient for IO access. Having this system ready to connect immediately after placement prevents delays in resuscitation.

Site choice depends on the patient’s age, anatomy, and clinical condition. The proximal tibia is the most frequently used site, located two fingerbreadths below the tibial tuberosity on the anteromedial surface. In adults, the proximal humerus is often preferred due to high marrow flow rates and shorter distance to the central circulation. The distal tibia and distal femur can be considered in select cases where the primary sites are unavailable.

Accurate landmarking is essential. For the tibia, palpate the tibial tuberosity, move approximately 2 cm medially and slightly distally, and select the flat bone surface. Care must be taken in children to avoid the epiphyseal growth plate, which can cause long-term deformity if damaged. For the humerus, position the patient’s arm against the torso with the hand resting on the abdomen, palpate the greater tubercle, and insert at the most prominent aspect, directing slightly toward the opposite shoulder.

Technique requires stabilizing the limb firmly and inserting the IO needle at a 90-degree angle to the bone surface. With manual needles, apply steady pressure and a twisting motion until a sudden “give” indicates entry into the marrow. With drill-assisted devices, maintain firm control and stop immediately once entry is achieved. Correct placement is confirmed if the needle stands upright without wobbling, aspiration of marrow is possible, and saline flushes without significant resistance or swelling.

Once placement is confirmed, nurses should secure the device with adhesive dressings or a commercial stabilization device to prevent dislodgement. The IV tubing should be attached promptly, and a pressure-assisted fluid infusion started. Continuous observation of the site during the first flush and infusion is essential to detect early extravasation.

Comprehension Quiz

Please complete the following: Quiz: IO 2 - Placement and Procedure - WACS

Extravasation is the most common complication, occurring when fluid leaks into surrounding tissue instead of entering the marrow cavity. This may present as swelling, firmness, or pain at the site. Nurses should monitor closely during each flush and infusion, stopping immediately if infiltration is suspected. Failure to detect extravasation—which is indicated by swelling, increased resistance to infusion, unexpected pain, or changes in skin color and limb tension—can result in compartment syndrome, requiring urgent surgical intervention

Infection is another risk. Although uncommon, osteomyelitis can develop if sterility is compromised. Redness, warmth, or discharge around the site must be reported immediately. Nurses should ensure that the insertion site is covered with a sterile dressing and inspected regularly. Prolonged use beyond 24 hours significantly increases infection risk, so removal planning must be documented.

Dislodgement of the IO needle is also frequent, particularly if the limb is moved or not properly stabilized. Nurses should verify that the device is firmly secured after placement and monitor for loosening or leakage. Any instability should be reported, and the site should be abandoned if the device cannot be stabilized.

Aftercare includes transitioning the patient to IV or central venous access as soon as feasible, typically once perfusion improves and peripheral or central veins can be reliably cannulated. Nurses should document insertion time, plan removal accordingly, and notify the team if the device is approaching time limits. They should also record whether complications occurred and what corrective measures were taken.

Comprehensive documentation of IO insertion is essential for patient safety and legal accountability. The record should include the clinical indication for IO access, the chosen anatomical site, the type and size of IO device used, and the exact time of insertion. Details of the procedure should also be recorded - this includes whether the marrow was aspirated, whether a flush was successfully administered, and whether infusion flowed freely without resistance. If multiple attempts were made, each attempt and site should be listed to avoid reusing the same bone within 24–48 hours.

Consent details must be noted, including whether verbal consent was obtained, whether implied consent applied due to emergency, and whether family members were informed post-procedure. Any refusal or hesitation should also be documented if it influenced timing of the procedure. Finally, nurses should record the aftercare plan: anticipated duration of IO use (less than 24 hours), scheduled transition to alternative access, and monitoring instructions. Documentation of complications—extravasation, infection, or dislodgement—must be explicit, including actions taken. This ensures continuity of care and informs the next provider’s clinical decisions.

When personnel shortages exist, nurses may be required to manage multiple roles: preparing sterile fields, positioning the patient, and monitoring during insertion. Prioritization is essential. Maintaining sterility with limited supplies should take precedence, even if a full sterile field is not possible. Firm limb stabilization using available staff or improvised supports reduces risk of dislodgement when another assistant is not available. When commercial IO devices are unavailable, manual bone marrow needles, large-bore spinal needles, or orthopedic needles may be adapted for IO use, provided sterility is preserved. If pressure infusion bags are lacking, nurses can use a manual blood pressure cuff inflated around the IV fluid bag or apply continuous manual squeezing to achieve flow. These adaptations should only be used when standard equipment is unavailable, with vigilant monitoring for complications.

Comprehension Quiz

Please complete the following: Quiz: IO 3 - Complications and Aftercare - WACS

Cumulative Test

Please complete the following: IO Module Test

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