Background

Abdominal Aortic Aneurysms (AAAs) are common and present a significant risk of rupture and mortality when greater than 55 mm in size. For those patients where the risk of rupture outweighs the operative risks, repair is offered. At present, most patients in the UK are offered a minimally invasive endovascular approach.

EVAR is now established as a safe and acceptable alternative to open repair in suitable patients. In 2004 the EVAR-1 trial demonstrated a significant reduction in 30-day mortality from 4.6 to 1.6% and in-hospital mortality from 6.0 to 1.6% in patients receiving EVAR . Since then, mortality and complication rates have fallen further. Recent reports from the National Vascular Registry (NVR) document 0.7% mortality and a 5.1% morbidity for the 2870 endovascular repairs across the UK in 2017 .

However, the estimated cost of the procedure is £12,000 [3], which is not cost-effective when compared to open repair – the cost of endografts and the increased burden of follow-up means that costs are greater overall . The draft guidelines for aneurysm repair from the National Institute for Health and Care Excellence (NICE) published in 2020 ( https://www.nice.org.uk/guidance/ng156/informationforpublic) included a detailed cost analysis based on trial data which concluded EVAR is not cost effective, recommending EVAR is not used in fit or unfit, non-ruptured aneurysm patients.  After unprecedented stakeholder opinion and intervention from NICE, changing the guideline committees final recommendations, the guidelines were finally published (https://www.nice.org.uk/guidance/ng156/chapter/Recommendations-for-research). The guidelines state that “where open surgical repair can’t be carried out – for example because of medical or anaesthetic risks – EVAR can be considered”. However, cost-effectiveness is clearly an important issue that will be ever more important in years to come, given increasing healthcare costs and studies to attempt to find cost effective improvements are needed.

In addition, waiting times are increasing - the NVR report 2017 stated “The median delay at the majority of vascular units tended to fall within the range of 60 to 90 days. Nonetheless, the upper limit of the interquartile ranges shows that, at 16% of the vascular units (12 of 75), 25% of patients operated on in 2017 waited more than 140 days.” For aneurysm repair patients were cancelled, for a variety of reasons, but lack of facilities and hospital beds were among the prime reasons for cancellation. 

The average hospital stay for elective EVAR is 2 days (Interquartile range 1-4 days) . There is a need for a more efficient care pathway. There is a focus on shorter stays and readmissions in the “Getting It Right First Time” (GIRFT) agenda, which is a Nationwide report of vascular surgery performance. The variation in practice is clearly demonstrated in this work. Research into the potential of shorter stay pathways is very much needed, to include patient acceptability.

Short Stay Aneurysm Repair (STAR) is certainly achievable. The results of papers on this subject have recently been synthesized in a systematic review.  The patients involved are selected according to fitness, social and anatomical criteria. There is wide variation in reported rates of short stay EVAR compared to the overall volume of patients from 23-79% of the cohort. There is also significant variation in terms of the success in discharging patients after a short stay (from 70-96%).

One report describes a select group of 27 patients in Cambridge who received EVAR, discharged the day after surgery [6]. There were no safety issues detected and the perceived costs of a short stay EVAR were less in a rudimentary cost analysis. The highly specialized vascular centre in Zurich, Switzerland has published results for day case EVAR, to demonstrate feasibility . A protocol involving many elements of a fast-track programme and low-profile devices in the USA has shown that in selected patients, it is possible to perform next day discharge, with a low complication rate, mortality and readmission rate of 1.6% [8]. Despite these reports, which are now more than five years old, the concept of short stay aneurysm repair has not been adopted into practice. Some of the reasons for this are highlighted in the papers. 

The Cambridge study suggested only 33% of patients are suitable for discharge the day after surgery, achieved in 81% of cases and even for these patients concluded that “an established pathway is required in order for [the potential benefits of next day discharge after EVAR] to be realized” as patents were not adequately prepared. Since this paper examined the utility of next day discharge (two bed day occupancy rather than less than 24 hours), this would seem to be vital before widespread adoption. The Swiss paper, and the more recent US study describe good outcomes for short stay EVAR but have not considered the costs and outcomes relevant to the National Health Service (NHS) and the selection and follow-up of these patients is not documented.

The success of short stay or day case surgery programmes has been demonstrated for many conditions such as coronary angiographic procedures and laparoscopic cholecystectomy where there is now evidence that day case procedures are feasible, acceptable, and safe . There have been many successful case histories of reducing length of stay in various specialties, which are vitally important to understanding implementation strategies. From study of these detailed case histories there have been several tools to empower units to introduce short stay pathways and release capacity in the health system. These include diagnosis, process mapping and problem-solving tools as well as strategies for staff involvement and reducing waste. Crucial to the success of these pathways appears to be design with a patient-centred approach . Evidence synthesis from a publication from the National Institute for Health Research (NIHR) Health Service and Delivery Research programme has highlighted a consistent reduction in the length of stay of 0.5-3.5 days compared with conventional care without increasing post-operative complication rate, readmissions or reducing patient outcomes . Given that a large proportion of patients at present are sent home at 2-4 days using current pathways  it would seem reasonable to suggest that a short stay, 23-hour pathway could become the norm for most patients undergoing elective EVAR.

Investigation has been conducted by the study team specifically to understand how a 23-hour pathway may be best designed to overcome organizational and personal barriers to implementation, including detailed discussions with patients and their families, a 38-patient audit in four sites to demonstrate organizational, procedure and patient factors affecting discharge.

These preparatory investigations have highlighted some of the necessary pre-operative and follow-up arrangements that will have to be in place to support patients, such as patient information, pre-booked telephone calls and appointments and placed a primary emphasis on social discharge planning, hence the need to incorporate a design phase in the research plan.

 RATIONALE FOR CURRENT STUDY

It seems that the potential benefits of short stay EVAR could include increased satisfaction and care for recovery in a home environment, reduced adverse event rates from hospital care and a vital reduction in utilization of hospital services perhaps translating into a reduced cost. In addition, the option of a safe short-stay EVAR procedure could allow many urgent patients to be treated in short stay wards away from the general ward which may be overrun with COVID. There are, however, many barriers to implementation including patient, carer, and General Practitioner (GP) concerns regarding late recognition of and being away from immediate medical care for major complications and an increased burden on the family unit, GPs & community health and social care.

On a nationwide basis, we do not know the proportion of patients who would be suitable for, or accept 23-hour EVAR, whether this leads to unreported major adverse events or readmissions, unrecognized complications and most importantly whether patients, their families and family practitioners are satisfied with this approach, outcomes highlighted in the NHS outcomes framework 2013/14 . Equally we do not know how institutions across the NHS would take up this approach.

We hypothesise that with appropriate multi stakeholder co-design of a short stay aneurysm pathway, there is a significant cohort (greater than 50%) of EVAR patients who would be eligible and accept to undergo STAR, be discharged within 23 hours without any increase in complications or mortality and without a decrease in patient satisfaction or excessive burden on community resources. Consequently, we hypothesize that the cost effectiveness of EVAR can be significantly improved.

 INCLUSION CRITERIA 

Patients may be included in the study and offered treatment using the STAR pathway if:

⦁    They have been assessed as suitable for standard infrarenal EVAR within the manufacturer’s “Instructions for Use” for the chosen endograft. 
⦁    Age over 55 (effectively excluding connective tissue disease)
⦁    Fully independent at home or adequate provision for home care after discharge which would enable patients to perform basic activities of daily living including mobility, eating, drinking and bathing.  
⦁    Living with a partner or family member or having similar help available for the first 24-hours after discharge from hospital.
⦁    Transport to attend the hospital in which they were treated within 1 hour for the first 24-hours after discharge. Should an ambulance not be readily available to attend hospital within this timeframe, patients must be made aware and agree to make their own transport arrangements.
⦁    Capable of complying with Protocol requirements, including follow-up.
⦁    An Informed Consent Form signed by the participant or legal representative. 

EXCLUSION CRITERIA

Patients will be excluded from being offered treatment using the STAR pathway (with reasons carefully documented) if there is:

⦁    Significant cardiac disease defined as one or more major predictors of increased perioperative cardiovascular risk according to the American College of Cardiology Cardiac Risk Classification (Appendix 3), which remain untreated at the time of surgery.
⦁    Significant renal failure (pre-operative creatinine level of over 150 μmol/L or GFR less than 30mL/min/1.73m2 indicating severe chronic kidney disease (stage IV).
⦁    Significant respiratory disease needing increased post-operative care not available in the home environment (e.g., nebulisers or oxygen therapy which is not set-up at home).
⦁    Any other condition, which in the opinion of the multidisciplinary team makes discharge within 23-hours unsafe.
⦁    Patients who lack capacity to consent to 23-hour EVAR will be excluded from the study.
⦁    There is concurrent enrolment in another drug or medical device study or have recently been involved in any research prior to recruitment

WITHDRAWAL CRITERIA 

The patient will remain free to withdraw at any time from the protocol treatment and study follow-up without giving reasons and without prejudicing their future care and should notify the Investigator in this event – these patients will be treated from this time as patients that are undergoing standard EVAR. The Investigator may also withdraw the participant from the study at any time based on his / her medical judgment. 

Below are the downloadable documents for the STAR study . Please click on the appropriate link for information.

Protocol and other essential documents

STAR STUDY PROTOCOL V.1.1 (doc)

STAR CLINICAL PROTOCOL

STAR STUDY PATIENT INFORMATION SHEET V2.0 ( 05/07/2024)

STAR PATIENT INFORMED CONSENT FORM V.1.1 (doc)

EVAR School Booklet.pdf

Eligible patients will be recruited from the following NHS Trusts:

IMPERIAL COLLEGE HEALTHCARE NHS TRUST
NORFOLK AND NOWRICH UNIVERSITY HOSPITALS NHS FOUNDATION TRUST
FRIMLEY HEALTH NHS FOUNDATION TRUST
THE NEWCASTLE UPON TYNE HOSPITALS NHS FOUNDATION TRUST
LEICESTER UNIVERSITY HOSPITALS NHS TRUST

Study Summary 

An abdominal aortic aneurysm (AAA) is a ballooning of the main blood vessel (the aorta) that travels down through your tummy. An AAA can grow to a large size over time, and it may burst (rupture), causing life-threatening internal bleeding. The standard method to prevent the AAA from bursting is to re-line the aorta with a material tube that is strengthened by metal struts. This is inserted in a collapsed state, constrained by a delivery device, through the blood vessels from the artery in the groin, positioned in the aorta below the arteries supplying the kidneys and opened (deployed) under X-Ray guidance to fix it in place above and below the aneurysm. This excludes the aneurysm from the flowing blood and stops the aneurysm from expanding, reducing the risk of rupture. This is commonly known as a `keyhole' or minimally invasive approach called Endovascular (i.e., inside the aorta) aneurysm repair (EVAR). You will have discussed this procedure with your doctor.

Increasing waiting times in the National Health Service (NHS) are widely reported. Many in the NHS consider waiting times to get patients with aneurysms treated much too long for an urgent condition. The reasons for this being limitations in resources including beds and staff expertise. EVAR, to treat abdominal aortic aneurysm, has been shown to be safe and effective and does reduce the burden on health services however the length of stay in hospital is still two days or more in most patients; up till now it has not been found to be cost-effective compared to the traditional open surgical approach. COVID-19 pandemic has further restricted the resources available to get aneurysm patients treated even with keyhole techniques.
This study is designed to evaluate whether short stay EVAR (being in hospital for <24 hours for the operation) is acceptable to a wide number of patients and clinically effective. We will also study whether it is worthwhile to implement in terms of cost.
Although short stay EVAR or day case EVAR has been tried before, it has not been in any way universally accepted and so needs to be studied scientifically. One of the main factors that has not been studied is the patient view and so satisfaction, quality of life and the patient report outcome measures will be of prime importance.

Contact for patients, relatives and carers:

If you are a patient taking part in this study or a relative or carer of a study participant and you would like more information about the study please contact:
STAR Study Co- ordinating Centre
Email: starstudy@imperial.ac.uk   

We  will be happy to discuss any concerns you have with the study or answer your questions.

Useful links: 

For independent advice about taking part in research, you can visit: https://www.imperial.nhs.uk/research/taking-part  
More information on vascular diseases or procedures are also available from: 
•    The Circulation Foundation https://www.circulationfoundation.org.uk/    
•    The National Institute for Health and Clinical Excellence (NICE) is the independent organisation responsible for providing national guidance (recommendations) on whether interventional procedures are safe enough and work well enough to be used routinely in the NHS.  You can read the NICE guidance on stent-graft placement in abdominal aortic aneurysms here: https://www.nice.org.uk/guidance/ta167  

Newsletters

STAR NEWSLETTER _1st EDITION _AUGUST 2024