ERICA Arrest Trial

Sudden out-of-hospital cardiac arrest is the most common mission for the East Anglian Air Ambulance (EAAA). Around one in five of our cardiac arrest patients survive, but across the country the rate of survival is below 10% – this condition needs new treatments to help improve survival. The current management of out-of-hospital cardiac arrest (OHCA) includes cardiopulmonary resuscitation (CPR) to supply blood to the heart and brain. Optimising blood flow to the heart and brain is important for survival. However, even during well-performed CPR, blood flow to the brain and heart is well below normal levels. In animal studies, putting a balloon into a large artery close to the heart leads to an improvement in heart and brain blood flow, and short-term survival from cardiac arrest. Reports from human studies have shown similar effects in patients who suffer from cardiac arrest. The aim of the research is to assess the feasibility of delivering the device in 20 carefully selected patients, who have suffered a cardiac arrest. This is the first study of its kind in the UK.

EAAA has clinicians highly trained and experienced in resuscitation for cardiac arrest and inserting medical tubes into patients’ arteries and veins. We are undertaking a ‘first in the UK’ research study, investigating the effectiveness of placing a balloon catheter into the aorta in OHCA patients, who are undergoing resuscitation (CPR). This project is supported by and undertaken in partnership with Queen Mary University of London.

• Patients attended by East Anglian Air Ambulance who have had an out-of-hospital cardiac arrest • Aged 18 to 80 years • No flow (time without CPR) <10 minutes • In cardiac arrest on arrival of EAAA team arrival

The risks of the patient being in the study are negligible. There is a very small risk (less than 1 in 300) that the artery in the leg might sustain some damage when we insert the balloon device, causing bruising or bleeding around the site. We minimise the risk of this by using ultrasound to locate the blood vessels so that we can access them safely. All complications and safety concerns are fed back to the research team, who interview the clinical team within 24 hours of a case to identify any safety issues and gather any learning points.

We are researching the benefits of this balloon technique, which could possibly make restarting the heart of cardiac arrest patients easier and giving them a better chance of recovery. If we can demonstrate this technique is feasible, we could use it on other patients to see if it improves overall survival rates from cardiac arrest.

Yes. This study has been approved by an NHS Research Ethics Committee and is being closely monitored by a safety committee as it recruits patients.

During the procedure being studied, full active resuscitation will continue to be provided by our EAAA crew and the ambulance service resuscitation teams. The delivery of the procedure will not adversely affect the resuscitation in any way – all the usual emergency procedures and medication treatments will continue as usual, in an attempt to restart the heart. The device is inserted into an artery in the patient’s groin and threaded into a larger artery close to the heart (the aorta). A small balloon is inflated which redistributes blood flow during CPR. It is a well-established technique in medical resuscitation, also known as REBOA (Resuscitative Endovascular Balloon Occlusion of the Aorta).

This study will test the feasibility of using this treatment in ongoing cardiac arrest, delivered by helicopter emergency medical service teams. We will also be assessing the blood pressure response to the treatment to see if improves blood flow to the heart muscle, and oxygen delivery to the brain during the resuscitation attempt – all of these might contribute to improvements in survival.

The cost of the special equipment and additional training needed to carry out this new intervention is around £5,000 per recruited patient, which is being funded by the Department of Health & Social Care. We are also receiving some study support costs from the East of England Clinical Research Network (National Institute of Health Research). Donations towards development and set-up of the study were gratefully received from the Rosetrees Trust, Dowager Countess Eleanor Peel Trust (DCEPT), The Charles Wolfson Charitable Trust, The Thriplow Charitable Trust, and The Helen Roll Charity.