South Central Ambulance Service is about to embark on a controversial new study, to test how best to treat people who have cardiac arrest.
Currently there is uncertainty about whether giving patients adrenaline, which has been used for more than 50 years as part of resuscitation, does more harm than good.
This trial, which is being led by Warwick University, is designed to answer that question but has prompted some ethical concerns.
Half of patients will receive a dummy medicine and half will get adrenaline - but as they will be unconscious there will be no consent gathered as the drug is administered.
Research studies of this type involve putting people into two groups where one group receive the active drug and the other group a dummy drug. The results are compared to see if one is better.
To try to make sure the groups are the same to start with, each patient is put into a group by chance. This study is a “double blind trial”, as neither the patient nor the paramedic will know in which treatment group someone was in.
Scientists will be able to analyse results based on the serial numbers attached to each.
The pilot phase of the study will involve Reading and Basingstoke ambulance stations. That will last until the end of March, with a staged full Trust roll-out from April.
It is being conducted to address the concern that clinicians and researchers have about the use of adrenaline in cardiac arrest. A growing body of scientific evidence suggests that although adrenaline may be better at restarting the heart for a few minutes to hours, it can cause severe brain damage resulting in death a few hours to days later without regaining consciousness.
In one recent study from the United States, less than half the number of people treated with adrenaline survived to go home from hospital compared to those that did not receive adrenaline.
People in UK suffer cardiac arrest outside hospital each year
People leave hospital alive following cardiac arrest
The ethics of the study have been approved at a national level based on European law, but there are still concerns over the lack informed consent regarding a life-and-death situation.
The real risk would be to continue to give treatments that may have been used for decades, but have not been properly tested to modern scientific standards.
Experts say the best treatment for cardiac arrest is good cardiopulmonary resuscitation and early defibrillation and this will remain unchanged throughout the trial.
Members of the public who do not wish to be enrolled in the PARAMEDIC-2 trial can choose to opt-out by requesting a stainless steel bracelet which has the words ‘NO STUDY’ engraved on it.
Local paramedics will be trained to look for these bracelets in the same way they do for other medical ID bands. This means that, in the event that a person has a cardiac arrest, he or she will receive the current standard treatment which may include adrenaline.