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Trial overview

The PARAMEDIC-3 trial is looking at the most effective way to treat someone when their heart suddenly stops working out of hospital by giving drugs through a vein or into the bone. Answering this question will help to improve future treatment of people who have a cardiac arrest.

Why is the trial needed?

Drugs such as adrenaline are widely used to treat cardiac arrest. The sooner these drugs are given the better the chance is that they will be successful.

Currently, paramedics normally give drugs into a vein. The problem with this is it can take several critical minutes to get lifesaving drugs into a vein. A new, faster way of giving drugs is to put a small needle into an arm or leg bone. This allows drugs to be injected directly into the rich blood supply found in the bone marrow. We do not currently know which is the best approach as none of the existing research is good enough to help paramedics decide how best to treat people with cardiac arrest.

When doctors, nurses and paramedics do not know the best way to provide a treatment it is common to do a clinical trial In this trial those enrolled were put in to two groups – half received drug treatment through a vein and half received it through a bone. At the end of the trial the results will be compared to see if one is better. To try to make sure the groups are the same to start with, each patient was put into a group by chance (randomly) through a process called randomisation.

The International Liaison Committee for Resuscitation (ILCOR) has called for a definitive clinical trial to assess if the Intravenous (IV) or Intraosseous (IO) route is more effective to treat out-of-hospital cardiac arrest patients.

Where is the trial being conducted?

The trial is being delivered by the University of Warwick in partnership with the following ambulance services in England and Wales:

North East Ambulance Service NHS Foundation Trust
North West Ambulance Service NHS Trust
West Midlands Ambulance Service University NHS Foundation Trust
East Midlands Ambulance Service NHS Trust
South Western Ambulance Service NHS Foundation Trust
South Central Ambulance Service NHS Foundation Trust
South East Coast Ambulance Service NHS Foundation Trust
London Ambulance Service NHS Trust
East of England Ambulance Service NHS Trust
Welsh Ambulance Services NHS Trust

When will the trial take place?

The trial started in May 2021 with recruitment to take place between September 2021 - October 2023. The trial will finish in March 2025.

Who will be included in the trial?

This trial will include patients who have a cardiac arrest outside of hospital, in areas served by participating ambulance services. People who are pregnant, under the age of 18 or who already have vascular access will not be included.

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Please direct all enquiries for the PARAMEDIC-3 trial team.

Telephone: 07385029213

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