Which is the preferred intraosseous access site for a pediatric patient?

• A. Distal femur
• B. Proximal tibia
• C. Distal humerus
• D. Proximal radius

Answer: (B)

In emergencies when IV access is not quickly obtainable in a child, giving fluids and medications via the bone marrow is the fastest route. The proximal tibia is the preferred IO site because its landmarks are easy to locate—just below the tibial tubercle on the anteromedial proximal tibia—so you can access the marrow quickly without searching for a difficult spot. This region provides a large, forgiving metaphyseal cavity that allows rapid infusion with a reliable flow, and when placed correctly it minimizes risk to growth plates and surrounding structures. While other sites like the distal femur, proximal humerus, or distal radius can be used, they are more technically demanding or carry higher risk in small children, making the proximal tibia the best first choice for pediatric IO access.