The initial results from the British Cardiovascular Intervention Society's Out-of-Hospital Cardiac Arrest Pilot Registry, which records information from the time of cardiac arrest, right through hospital stay and extended follow-up of patients, has had a positive impact on the referral patterns and outcomes for cardiac arrest patients.

The registry’s research team, based at Essex Cardiothoracic Centre, have used the registry to record information from a pilot of a new pre-hospital conveyance algorithm - designed to offer guidance to ambulance staff on which centres to take a patient to if they recover a pulse after an out of hospital cardiac arrest.  This pathway diverts patients with a potential higher chance of having a cardiac cause for their arrest and needing acute cardiac care to a cardiac arrest centre where they can receive appropriate care. The registry, which only includes patients who have had a cardiac arrest from a suspected cardiac aetiology, began collecting data in October 2022 and now had over 770 cases.

“We know cardiac arrest is a huge problem in the UK and around the world, and the survival rates between 8-10% in the UK are behind our European neighbours and North America. One of the main problems is that it is difficult to affect change in cardiac arrest that is going to improve mortality,” explained Dr Rupert Simpson (Mid and South Essex NHS Foundation Trust). “Understanding the extent of the problem, particularly on a local level is a challenge, as there is a lack of data on inpatient stay, local practices and patient follow-up are not being documented.”

Currently, there are no guidelines concerning patient referrals after a cardiac arrest and patients are usually taken to the nearest suitable centre for treatment. The team from Essex adopted a more nuanced approach that considers the initial heart rhythm patients present with. Dr Simpson stated that there is evidence suggesting that if a patient has a particular rhythm, one that can be defibrillated (a so-called ‘shockable rhythm’), the patient may have a higher likelihood of having a cardiac aetiology for their arrest. If the patient is then brought to a cardiac arrest centre, the patient may then receive treatment that could result in more positive outcomes.

“Ambulance teams already collect really useful information and researchers at Warwick University have done some excellent work with that data. The next step was to gather the follow-up data, with particular focus on longer term functional, neurological and psychological outcomes,” added registry lead, Dr Thomas Keeble (Consultant Cardiologist, Essex Cardiothoracic Centre, UK). “Essentially, what this dataset does is build upon the pre-hospital ambulance data, add in the in-patient hospital data and includes the follow-up data. We now have a holistic registry - complete data from the time of the cardiac arrest to follow-up. A lot of the data we are collecting is already collected within the NHS, but it is in lots of different databases and has not been amalgamated. This is the first time all the data has been collected in a single registry.”

“One of the key advantages of using the Dendrite system was their unique electronic patient-reported outcome measures (ePROMs) facility, that gave the us the ability to assess a patient's health status (QoL) at a particular points in their follow-up,” explained Dr Simpson. “This is crucial in assessing whether our interventions are improving outcomes in the longer term.”

Since they launched the algorithm across Essex, they have managed to increase the proportion of patients coming to their centre with a cardiac arrest secondary to an initial shockable rhythm. Prior to the registry, the proportion of these patients across Essex coming to the Essex Cardiothoracic Centre was about 44% and since the launch of the new algorithm that number has increased to about 60%.

“We are not aware of any guidelines for pre-hospital teams regarding the referral of cardiac arrest patients and we are the first centre to be running this pilot algorithm, on behalf of the British Cardiovascular Intervention Society. So, depending on the outcomes of this pilot, it has the potential to really transform patient care on a country wide basis,” Dr Keeble highlighted.

Moreover, for the research team the project fully underpins the principles of ‘Getting It Right First Time (GIRFT)’ report for cardiology, which emphasised the need for better data collection, reducing clinical variation and supporting cardiology services to work more flexibly through clinical networks.

“We know that about the same number of patients arrive at our centre also arrive at the five non-cardiac centres (Harlow, Colchester, Southend, Basildon and Chelmsford),” Dr Keeble added. “Now, it is not feasible for our centre to take all those patients, but we can take those patients who we think ae most likely to be presenting with a cardiac aetiology and give them the most effective treatments to hopefully improve their outcomes. Ultimately, it is about getting the right patient, at the right time to the right centre to give them the right care. Of course, getting the patient to the right centre also benefits ambulance teams as they are avoiding unnecessary secondary transfers with intensive care teams.”

“The main goal of the registry was the capture what we are doing locally in Essex and hopefully establish a blue-print for a UK-wide cardiac arrest registry. This unique web-based registry has now been adopted by the British Cardiovascular Intervention Society as a pilot registry and we are hoping the registry will be rolled out nationally,” said Dr Simpson. “When we complete this initial project in April 2023, it will be really interesting to compare the before and after group to see the impact the algorithm had had on patient outcomes.”

“As ever, to recognise the full potential of this project, there will need to be national roll-out that is sensitive to local healthcare systems, geographical variation, commissioning of services and the populations they serve. In the first instance, we have are expanding the registry to include selected other sites first to trial the usage and in time we hope to include all UK centres treating cardiac arrest patients,” Dr Keeble concluded.

The East of England Cardiac Network provided funding for this registry.

About Dendrite

Dendrite Clinical Systems is a UK-headquartered international company with over a 30-year track record as a specialist provider of secure clinical registries, analysis software and consultancy services for the international healthcare sector, specifically for clinical research, multi-centre real-world studies, observational registries, international, national and hospital clinical databases.

Dendrite has been recognised as a leading provider of clinical registries across various specialties with a unique track record of implementing over 200 major clinical registry systems globally including systems for major research projects for medical device companies, CROs and pharmaceutical companies.