In emergency departments, ambulances or disaster sites, deciding to use an intraosseous (IO) access needle and successfully establishing vascular access epitomizes the technical proficiency and decision‑making capability of resuscitation teams. Authoritative global and domestic guidelines have elevated its status to a critical life‑support intervention, and skilled manipulation combined with an in‑depth understanding of complications ensures its maximum therapeutic benefit.

Guideline Consensus: From Backup to First‑Line Option

Previously, IO access was often regarded as a last resort following failed intravenous (IV) access attempts. This concept has now been completely overturned. Guidelines from the American Heart Association (AHA), European Resuscitation Council (ERC) and International Liaison Committee on Resuscitation (ILCOR) explicitly recommend early IO access if rapid IV access cannot be achieved during emergency care. For cardiac arrest patients in particular, guidelines stress that IO access is superior to endotracheal drug administration.

The Chinese Expert Consensus on Clinical Application of Intraosseous Infusion Access provides clear operational recommendations: during resuscitation of critically ill patients, intraosseous access shall be established immediately if two peripheral venipuncture attempts fail or IV access is anticipated to be difficult (e.g., requiring more than 90 seconds). This marks the upgrade of IO access from a "backup solution" to a first‑line lifeline equivalent to IV access.

Puncture Site Selection: Anatomy‑Based Decision‑Making

Site selection balances ease of operation, success rate and safety. The proximal tibia (1–2 cm medial and inferior to the tibial tuberosity) is the preferred site per consensus recommendations, owing to distinct bony landmarks, minimal soft‑tissue coverage, proximity to no major neurovascular structures, and compatibility with cardiopulmonary resuscitation (CPR) procedures.

When the tibia is unavailable (e.g., fractures, severe trauma), the proximal humerus (inferior to the greater tubercle) serves as an excellent alternative, featuring a large medullary cavity and abundant blood flow, especially suitable for rapid high‑volume fluid resuscitation. Sternal access (e.g., Pyng Medical's FAST1 system) is used in military or specific pre‑hospital settings due to its central location and thin cortical bone, though specialized training is required for its use.

Operational Workflow: Standardization Is Essential

Standardized procedures form the cornerstone of complication reduction, with key steps as follows:

• Localization and preparation: Palpate to identify bony landmarks, followed by strict disinfection and draping.
• Puncture: For battery‑powered devices (e.g., EZ‑IO®), select an appropriately sized needle, attach it to the powered driver, and insert vertically into the skin until a "give‑way" sensation is felt, then stop advancement.
• Confirmation and fixation: Remove the stylet and attempt aspiration with a syringe; bone marrow blood may be obtained (not mandatory but confirmatory). Perform rapid flushing with 5–10 mL of normal saline and check for subcutaneous swelling to confirm patency and no extravasation. Secure the needle firmly with dedicated fixation devices afterwards.
• Connection and infusion: Attach infusion tubing to initiate rapid fluid delivery. For conscious patients, administer 2% lidocaine via the IO route for local anesthesia to relieve distending pain during infusion.
• Removal: Indwelling time is recommended not to exceed 24 hours; switch to IV access as soon as the patient stabilizes after critical illness. Apply adequate compression to achieve hemostasis after needle removal.

Identification and Prevention of Complications

Though relatively safe, IO access carries potential complications requiring vigilance:

• Fluid extravasation: The most common complication, mostly caused by overly deep penetration (through the opposite cortex), superficial insertion, needle displacement or prolonged indwelling time, presenting as local swelling and increased skin temperature. Precise depth control, proper fixation and close monitoring are core preventive measures.
• Infection: Including local cellulitis and rare osteomyelitis. Strict aseptic technique is fundamental, and the widespread use of single‑use sterile needles has greatly reduced associated risks.
• Fracture and growth‑plate injury: Rare, mostly related to improper operation or severe osteoporosis in patients. Puncture of the epiphyseal plate shall be avoided in children.
• Fat embolism: Extremely rare, theoretically possible.
• Compartment syndrome: Severe yet rare, often resulting from massive fluid extravasation into fascial compartments, requiring urgent surgical intervention.

Clinical Evidence Support

A systematic review and meta‑analysis focusing on children and adolescents demonstrated that the overall complication rate of battery‑powered IO devices is significantly lower than that of manual devices. Another study indicated that the first‑attempt success rate of IO access is markedly higher than IV access in trauma patients (92.3% vs. 62.3%), with shorter access establishment time. Case reports from Cangzhou Central Hospital in China also confirmed that IO technology successfully rescued 8 critically ill patients within 14 days with high safety, efficacy and no complications.

In summary, clinical application of intraosseous access needles is a science built on solid evidence, standardized workflows and meticulous detail management. It requires healthcare providers to master not only operational skills but also the decision‑making ability to make correct judgments in time‑critical emergencies, ensuring this "uncollapsible lifeline" remains fully functional.