Introduction

Ambulatory care is an umbrella term used in the UK to describe acute hospital care that is distinct from outpatient, accident and emergency, urgent treatment centres, or inpatient care, and is sometimes referred to as ambulatory emergency care (AEC).1 In other countries, particularly in Northern America, Europe and Australia, the term ambulatory care is generally used to describe primary care services, rather than hospital care provision, although countries such as Australia are starting to adopt the UK model.2 The diverse nature and format of ambulatory care services, both nationally and internationally, means that comparisons between services are difficult.

AEC developed over the last decade or so, mainly being promoted by emergency departments (EDs) and acute medicine, and initially focusing on specific conditions, often termed ambulatory care sensitive conditions.1 The British Association for Ambulatory Emergency Care was founded in 2011 to promote the development, adoption and expansion of the specialty of AEC across the National Health Service (NHS) in the UK, and continues to promote the expansion of same day emergency care (SDEC) principles and practice today.3 While the NHS England Urgent and Emergency Care Review Team issued guidance recommending that all NHS Trusts should implement AEC in 2015,4 historically, there was no generic model; such services were heterogeneous and varied widely in their organisation and service provision.1 5 AEC tended to be provided in a clinic style setting, or within acute medical units, aiming to avoid admission and facilitate early discharge, but a variety of models were used, with some NHS Trusts embracing AEC, whereas others continued to operate more traditional models of admitting patients for assessment.6 In fact the Kings Fund demonstrated large variations in the rate of admission for ambulatory care sensitive conditions, when considered by local authority area, after adjusting for differences in age, gender and deprivation within local populations.7 However, by 2018, some 95% of UK hospitals had some form of ambulatory provision, according to a recent national audit.8

Building on the previous work undertaken within AEC, to support non-admitted emergency care pathways, as part of urgent and emergency care transformation, SDEC is a new model of care that has been developed within the NHS,1 and was mandated by the NHS Long Term Plan.9 The National Strategy for SDEC was released in 2021.10 This review will focus on the UK only, given that this SDEC model is unique to the UK.

The model suggests that SDEC can meet local health needs by providing an alternative to ED attendance or hospital admission. It is intended for people with an urgent or emergency healthcare need, requiring hospital level care and diagnostics, beyond the scope of an urgent treatment centre and takes referrals from general practice, urgent treatment centres, ambulance services, the 111 service, as well as the ED. SDEC services are considered essential to the future provision of acute care, in an ageing society with limited healthcare resources, and are endorsed by both the Royal College of Emergency Medicine, and the Society for Acute Medicine.11

However, as with AEC, considerable service variation still exists within the SDEC model. Some organisations offer a broad range of specialties within their SDEC services, in addition to acute medicine: paediatrics, frailty, gynaecology, surgery and oncology. Whereas other organisations focus their SDEC model predominantly on acute medicine. Further, within acute medicine, some SDEC services focus on specific pathways, for patients presenting with particular conditions, such as low risk chest pain, cellulitis, low-risk pulmonary embolism, etc and exclude patients who do not fit a specific pathway.5 Some use a risk stratification tool such as the ‘AMB’ Score, a simple seven element scoring tool for ambulatory care,12–14 whereas others rely only on the National Early Warning Score, based on physiological observations,15 or other risk assessment tools.16 17 Others take a more inclusive approach, taking all medical referrals, as long as clinically stable,18 this is often termed a process driven approach.19

There is also variation in the staffing models for SDEC nationally, with some being consultant led, whereas other are led by advanced clinical practitioners (ACPs). Over the last decade or more, across the NHS, shortages of medical staff led to service transformation and a realisation that workforce development was required. This, in part, led to development opportunities for other registered clinicians, such as nurses and allied health professionals, into advanced practice roles. Advanced clinical practice is designed to enable the safe and effective development of skills, across traditional professional boundaries. ACPs are educated to master’s degree level or equivalent, with knowledge and skills that permit an expanded scope of practice, and undertake roles and responsibilities historically seen as being within the jurisdiction of medical staff.20 Advanced clinical practice was recognised in the NHS Long Term Plan9 as being central to transforming service delivery and meeting local health needs as a key part of contemporary workforce planning. There is a growing evidence base to support the safety and effectiveness of, and patient satisfaction with, ACP roles; while recognising that there is ambiguity and variability within ACP roles nationally,21 progress is being made towards role standardisation and accreditation.20 ACPs are ideally placed to support the development of SDEC services, given current medical workforce challenges.

This planned scoping review will focus on acute medical SDEC, as medical patients represent a significant proportion of emergency admissions in the NHS. Typically, up to 30% of these patients are discharged within 24 hours of arrival, suggesting that admission avoidance, through the use of SDEC services, would meet that need and reduce pressure on inpatient beds,22 as recommended in The NHS Long Term Plan.9 Where necessary, SDEC patients can attend again on subsequent days, for further investigation or review, rather than being admitted, but there is limited data on the patient experience of SDEC, and on the impact on patients of the requirement for repeated or multiple visits. Some services are developing this further, through the use of Virtual Wards and Hospital at Home,5 23 but these services are beyond the scope of this review, as they are distinct from SDEC.

An emerging evidence base suggests that ambulatory services in the UK may improve patient experience and reduce hospital admissions, reduce infection risk and deconditioning, and offer cost savings.24 However, ambulatory care provision has been heterogeneous, whereas SDEC now has a national strategy, with core requirements,10 although local variations remain significant, in terms of specialty coverage; and some ambulatory care services have simply been rebranded as SDEC. Embedding the SDEC national strategy should guide future service development in a more cohesive manner, leading to a more homogeneous service across the seven NHS regions. This, in turn, will support future research, as comparisons between services will be less subject to confounding.

Given that the SDEC model has been operational for a relatively short period of time, a review of the evidence base is indicated to establish what research underpins the model. It is not uncommon for new healthcare policies and initiatives to be rolled out, based on small pilot studies, in a top-down approach from the Department of Health, as political agendas often drive cost savings and efficiency, rather than substantive workforce transformation priorities, given the ever-increasing demand on the NHS.25–27 It remains to be seen whether medium-term and long-term costs savings are produced by SDEC services, given the requirement for additional pathways, estate and staffing, or whether this approach simply delays admission and/or increases severity of illness at presentation, particularly in the older, frail population. Economic analysis and specialty SDEC such as frailty SDECs are not considered further, as the focus of this review is on acute medicine.

Establishing existing evidence underpinning the SDEC model will identify gaps that require investigation through further research. Initial searches suggest that there is little published literature to date, so a scoping review was chosen as the appropriate type of literature review to map emerging evidence.28–31 The Joanna Briggs Institute (JBI) methodology for scoping reviews32 was chosen to provide structure to the review, and to support the development of a comprehensive overview of the available evidence in relation to adult medical SDEC in the NHS.

A preliminary search of MEDLINE, the Cochrane Database of Systematic Reviews, JBI Evidence Synthesis and PROSPERO was undertaken to ascertain if this topic had been investigated previously, and no current, or in progress, systematic reviews or scoping reviews on the topic were identified. This protocol has been registered with Protocols.io.33