The IO is an often-forgotten tool in our skill-set. Perhaps it is the perceived brutality of drilling into a patients bone mixed with a lack of training and practice. But it is an excellent (and rapid) route for delivering emergency treatment to the circulation of a crashing patient. If a patient has no IV access and needs rapid treatment (e.g. cardiac arrest in an IVDU patient) - site an IO (ideally humeral), get the treatment in then establish more secure access when time permits.