PARAMEDIC-3 is UK-wide randomised controlled trial investigating whether an intraosseous-first strategy is more effective than an intravenous-first strategy for drug administration in out-of-hospital cardiac arrest. The International Liaison Committee on Resuscitation has highlighted the need for a randomised controlled trial to answer this important research question. The trial is supported by leading organisations involved in cardiac care and resuscitation. Please click here to find statements of support - https://warwick.ac.uk/fac/sci/med/research/ctu/trials/paramedic3/support/

To recruit patients in to the PARAMEDIC-3, you must be a registered paramedic working in a participating NHS ambulance service, and have completed the trial training package. Specific arrangements vary by ambulance service, so please do get in touch with your ambulance service research team for more information.

Eligibility should be assessed at the point at which you are considering vascular access. This would normally be immediately in patients presenting.

The randomisation process differs slightly between ambulance services. If, once you have completed the training, you are unsure how the randomisation process works, please contact your ambulance service research team.

The randomisation determines the initial vascular access route. If you have attempted vascular access twice by the randomised route (e.g. two attempt at intravenous access), then you may choose the route for all further vascular access attempts.

The anatomical site where you insert the vascular access is entirely at your discretion. We do ask that you record the location on the patient report form.

All cardiac drugs can be given via the intraosseous route, but we are aware that some ambulance services require specific drugs are given intravenously. If you need to give a drug that may only be given intravenously, then intravenous access can be obtained for the purpose of giving that specific drug.

It is important that you notify your ambulance service research team of all randomised patients. The process by which you do this varies between ambulance service- please contact your service research team if you are unsure.

The trial is looking specifically the strategy for obtaining vascular access. All other aspects of patient treatment (e.g. drugs, airway, termination, choice of destination hospital) should be undertaken based on local policy and clinical guidelines (e.g. Resuscitation Council UK, JRCALC).

An independent NHS Research Ethics Committee has reviewed PARAMEDIC-3 and determined that the trial meets the criteria for enrolment without consent, as described in the Mental Capacity Act 2005. This is because the treatment being delivered is time-critical, and any delays to discuss trial participation with someone close to the patient will delay treatment and distract the ambulance clinician from patient care.