By doing this study, the investigators hope to learn whether patients with difficult to obtain IV access who are treated with IO access are more satisfied with their care and have better outcomes. The investigators are specifically studying the time difference between groups and the difference in the number of attempts required to obtain vascular access and begin to treat with fluids and medications. The study will also measure patient satisfaction and procedural pain, the frequency of central line placement, the length of stay in the hospital and emergency department, and adverse events to intravascular access to determine whether IO access can improve these measures.

The investigators hypothesize that the use of a protocol utilizing an IO device for select patients with failed IV access will reduce the time requirements to obtain vascular access, reduce the number of attempts needed to obtain IV access, reduce the ED LOS, and have no negative impact on patient satisfaction compared to the current ED practices.

Inclusion Criteria:

1. 18 years of age or older
2. Hemodynamically stable
3. Speaks English
4. Able to consent
5. Has difficult IV access

Exclusion Criteria:

1. Patients who are younger than 18 years of age, b) lack English fluency c) are unable to give informed consent d) require immediate central venous access e) have a history of osteomyelitis in the only target location of IO access f) have a fracture in the bone of the only target IO site g) have received an IO in the last 24 hours of the only target site h) are allergic to lidocaine i) pregnant or j) require a contrast CT scan as part of their ED care will be excluded.

While pregnant patients may benefit from rescue access the use of lidocaine to anesthetize the medullary space has not been studied in this population.