Intraosseous (IO) infusion is a rapid, safe, and effective method for obtaining vascular access in critically ill or injured patients when traditional peripheral intravenous (IV) access is difficult or impossible to establish. It provides a non-collapsible entry point to the systemic circulation via the bone marrow’s rich vascular network, allowing for the delivery of fluids, medications, and blood products at flow rates comparable to a central line. While powered drivers have become commonplace, the skill of manual IO insertion remains a fundamental and life-saving competency for healthcare professionals in emergency, pre-hospital, and military settings.
Indications and Contraindications: When and When Not to Proceed
Before any procedure, a clinician must first determine if it is appropriate. IO access is a bridge, not a final destination, intended for emergent situations.
Indications:
- Failed or Delayed IV Access: The primary indication is the inability to secure peripheral IV access in a timely manner (e.g., after two unsuccessful attempts or 90 seconds) in a patient requiring immediate vascular access.
- Cardiopulmonary Arrest: IO access is a first-line recommendation in resuscitation algorithms when IV access is not already present.
- Severe Shock or Hypoperfusion States: Patients in hypovolemic, septic, or cardiogenic shock often have collapsed peripheral veins, making IO a reliable alternative.
- Major Trauma: In patients with extensive burns, edema, or traumatic injuries, peripheral veins may be inaccessible.
- Status Epilepticus or Altered Mental Status: Combative or seizing patients can make peripheral cannulation extremely challenging.
Absolute Contraindications:
- Fracture of the Target Bone: Infusion into a fractured bone will lead to extravasation of fluids and medications into the surrounding tissue.
- Infection at the Insertion Site: Inserting a needle through cellulitis or an abscess can introduce bacteria into the bone, causing osteomyelitis.
- Previous IO Attempt in the Same Bone: The existing hole can serve as an escape route for infused fluids, leading to extravasation.
- Inability to Identify Anatomical Landmarks: Obesity, edema, or congenital deformity may obscure the necessary landmarks.
Relative Contraindications:
- Severe Bone Disease: Conditions like osteogenesis imperfecta or severe osteoporosis increase the risk of fracture during insertion.
- Presence of Orthopedic Hardware or Prosthesis: A previous surgery or joint replacement at the target site prevents safe access.
Anatomy and Site Selection
Proper site selection is paramount to a successful and safe procedure. The ideal site has a thin cortical bone, a large medullary cavity, and is distant from major neurovascular structures.
- Proximal Tibia (Most Common Site): This is the preferred site for both adults and children due to its easily identifiable landmarks and flat surface.
- Adult Landmark: Identify the tibial tuberosity, a prominent bony bump on the anterior aspect of the tibia, just below the patella (kneecap). The insertion site is approximately 2-3 cm medial to the tibial tuberosity on the flat anteromedial surface of the tibia.
- Pediatric Landmark: The tibial tuberosity is not fully developed in infants and young children. The landmark is found 1-2 cm distal to the patella and slightly medial, on the flat anteromedial surface. It is critical to aim slightly caudally (away from the joint) to avoid the epiphyseal (growth) plate.
- Proximal Humerus: This site offers potentially faster flow rates due to its proximity to central circulation.
- Landmark: With the patient’s arm adducted and internally rotated (hand on the abdomen), palpate the greater tubercle of the humerus. The insertion site is on the most prominent aspect of this tubercle. Insertion here requires a 45-degree angle postero-medially. Manual insertion can be more challenging at this site due to the thicker cortex.
- Distal Femur (Primarily Pediatric): Used when the tibia is unavailable.
- Landmark: Palpate the patella and move proximally 2-3 cm from its superior border, slightly medial or lateral to the midline.
Equipment Preparation
As with any invasive procedure, having all necessary equipment organized and accessible is crucial for efficiency and sterility.
- Personal Protective Equipment (PPE): Gloves, eye protection.
- Manual IO Needle (e.g., Jamshidi or Dieckmann needle) of appropriate size.
- Antiseptic Solution: Chlorhexidine gluconate or povidone-iodine swabs.
- Sterile Drapes (optional).
- Local Anesthetic: 1-2% Lidocaine without epinephrine, with a 3-5 mL syringe and a 25-gauge needle (for conscious patients).
- Two 10 mL Syringes filled with sterile normal saline.
- Syringe for marrow aspiration (can be one of the prefilled saline syringes).
- Pressure Bag.
- IV Tubing and desired infusion fluid.
- Catheter Stabilization Device or sterile gauze and tape.
- Sharps container.
Procedure for Manual Insertion
- Prepare the Patient and Yourself: Don PPE. Position the patient supine. For tibial access, place a small roll under the knee to slightly flex it and expose the insertion site. If the patient is conscious and hemodynamically stable, explain the procedure to reduce anxiety.
- Identify Landmarks and Prepare the Site: Meticulously palpate and confirm the anatomical landmark on the chosen bone (e.g., the anteromedial surface of the proximal tibia). Cleanse the skin over a wide area with the antiseptic solution using a sterile technique and allow it to air dry completely.
- Administer Local Anesthesia (for conscious patients): If time and patient condition permit, administer local anesthetic. Infiltrate the skin, subcutaneous tissue, and, most importantly, the highly sensitive periosteum (bone surface) with 2-5 mL of lidocaine.
- Perform the Needle Insertion:
- Select the correct length needle; the tip must be able to pass through the cortex into the medullary cavity.
- Grasp the IO needle firmly in the palm of your dominant hand, with your index finger extended along the shaft to guide and stabilize it. This provides control and prevents advancing too far.
- Position the needle tip over the identified landmark at a 90-degree angle to the bone.
- Apply firm, steady, downward pressure while making a gentle, continuous twisting or oscillating motion with your wrist. Do not rock the needle. The goal is to drill through the bone, not punch through it.
- Continue this pressure until you feel a distinct “pop” or a sudden loss of resistance. This tactile feedback signifies that the needle tip has passed through the hard cortical bone and entered the soft medullary cavity. Stop advancing immediately upon feeling this loss of resistance to avoid penetrating the posterior cortex.
- Confirm Correct Placement: Confirmation is a critical safety step to prevent extravasation and compartment syndrome.
- Stability: The needle should stand firmly on its own within the bone, perpendicular to the skin. If it is wobbly, it is likely only in the soft tissue.
- Aspiration: Remove the stylet. Attach a syringe and attempt to aspirate. The appearance of blood-tinged bone marrow is a definitive confirmation. Note: Aspiration may not be successful in up to 40% of cases, especially in states of severe hypovolemia.
- Saline Flush: Attach a 10 mL prefilled saline syringe and flush briskly. The flush should flow easily with minimal resistance.
- Observe for Extravasation: While flushing, palpate the area around the insertion site. The absence of swelling, infiltration, or tenderness supports correct placement. If swelling occurs, the infusion must be stopped immediately, and the needle removed.
- Free-Flowing Infusion: Connect the IV tubing and apply a pressure bag (inflated to 300 mmHg). Fluids should flow freely without difficulty. Gravity infusion is often too slow due to the resistance of the marrow space.
- Secure the Catheter: Once placement is confirmed, secure the IO catheter firmly using a dedicated stabilization device or a well-constructed bridge of rolled gauze and tape. An unsecured IO line is easily dislodged.
- Manage Pain (for conscious patients): Infusion into the marrow space can be intensely painful. A slow intraosseous infusion of 2% preservative-free lidocaine (e.g., 40 mg for an adult) prior to the main fluid bolus can significantly blunt this pain.
Potential Complications
While generally safe, complications can occur:
- Extravasation and Compartment Syndrome: The most common complication, resulting from incorrect placement, dislodgement, or penetration through the posterior cortex.
- Infection: Cellulitis at the site or osteomyelitis (bone infection) can occur, although the risk is low (<1%) with proper aseptic technique.
- Fracture: An iatrogenic fracture can occur, especially in patients with bone disease or if excessive force is used.
- Fat Embolism: A rare but serious complication.
The IO line should ideally be removed within 24 hours and replaced with definitive vascular access as soon as possible to minimize these risks. Manual IO insertion is a powerful tool in the arsenal of any emergency provider, offering a lifeline when all others have failed. Mastery of this skill requires knowledge, practice, and a meticulous approach to technique and patient safety.
References
- Paxton, J. H., & Knuth, T. E. (2018). Intraosseous Vascular Access. In R. S. Hockberger & R. M. Walls (Eds.), Rosen’s Emergency Medicine: Concepts and Clinical Practice (9th ed., Vol. 1, pp. 45-48). Elsevier.
- Deakin, C. D., Nolan, J. P., Soar, J., Sunde, K., Koster, R. W., Smith, G. B., & Perkins, G. D. (2010). European Resuscitation Council Guidelines for Resuscitation 2010 Section 4. Adult advanced life support. Resuscitation, 81(10), 1305–1352.
- Fowler, R., & Gallagher, J. V. (2020). Intraosseous Infusion. In StatPearls. StatPearls Publishing. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK482223/
- Petitpas, F., Guenezan, J., Vendeuvre, T., Scepi, M., Oriot, D., & Mimoz, O. (2016). Use of intra-osseous access in adults: a systematic review. Critical Care, 20(1), 102.
- Tobias, J. D., & Ross, A. K. (2010). Intraosseous infusions: a review for the anesthesiologist. Anesthesia & Analgesia, 110(2), 391–401.
