Intraosseous infusion (IO) is the process of injecting directly into the marrow of a bone. This provides a non-collapsible entry point into the systemic venous system. This technique is used to provide fluids and medication when intravenous access is not available or not feasible. Intraosseous infusions allow for the administered medications and fluids to go directly into the vascular system. A comparison of intravenous (IV), intramuscular (IM), and intraosseous (IO) routes of administration concluded that the intraosseous route is demonstrably superior to intramuscular and comparable to intravenous administration (in delivering paediatric anaesthetic drugs). This route of fluid and medication administration is an alternative one to the preferred intravascular route when the latter cannot be established in a timely manner. Intraosseous infusions are utilized when trauma patients have compromised intravenous access and need immediate delivery of life saving fluids and medications.