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What is happening with NHS ambulance delays?

BMJ 2023; 380 doi: (Published 23 January 2023) Cite this as: BMJ 2023;380:p142
  1. Zainab Hussain
  1. The BMJ

After months of negative headlines, Zainab Hussain asks just how bad response and handover times are, why, and what are the proposed and possible solutions?

How are ambulance response times measured?

Ambulance response times are measured by the time taken for the most appropriate response to arrive at a patient’s location after a 999 call, and calls are triaged into four categories.

Category 1 (C1) encompasses life threatening conditions and conditions needing immediate intervention or resuscitation (such as cardiac arrests), while category 4 (C4) comprises non-urgent conditions that still need to be assessed within a clinically appropriate timeframe.1

Response times for the ambulance service in England have consistently missed their targets since summer 2021, and the most recent data published by NHS England show that this remained the case in November 20222 (see table 1). Ambulance workers are now striking and a stream of news stories throughout 2022 painted a picture of a service in crisis.

Table 1

Ambulance response times against target

View this table:

What is causing the delays?

Demand, for one thing. According to the London Ambulance Service, the number of recorded incidents for C1, C2, and C4 have steadily increased from 2019-20 to 2021-22 (see table 2). For C4, the number of incidents has increased about 10-fold.3

Table 2

Number of incidents

View this table:

A spokesperson for the Association of Ambulance Chief Executives (AACE) says, however, that the biggest bottleneck is hospital handover.

Handover data measure the time between an ambulance arriving at the hospital and the hospital taking responsibility for the patient. In the week to 11 December 2022, more than a third of patients waited over half an hour to be transferred from ambulance to hospital: 17% of handovers took more than an hour and a further 17% took between half an hour and an hour.

“Ambulance resources are being consumed when ambulances are queuing outside emergency departments because they’re unable to offload a patient,” an AACE spokesperson says. “This adversely impacts every other part of the ambulance service’s operations.”

In the week to 11 December 2022, the ambulance service in England lost more than 29 000 hours to handover delays, according to data collated by NHS England.

What is behind the handover delays?

AACE says it is a symptom of bigger problems in the NHS and beyond. Handover delays are attributed to myriad factors, including increasing demand, workforce gaps across health and social care, the physical capacity of buildings, and the build up of patients unable to see their GPs. This makes it a complex system problem, requiring a system response.

The biggest problem, AACE says, is patient flow—or lack of it—through hospitals and the wider health and social care system. The inability to discharge patients means that on average 12 900 patients a day spent more time in hospital than needed in July 2022—11% more than the previous month—according to NHS England.4

These systemic problems have a knock-on effect on handover delays—which then cause further ambulance response delays because ambulances waiting to hand over patients to emergency departments can’t respond to more calls for help. “We’ve got hospitals that have around 150 inpatients a day that are fit for discharge,” AACE told The BMJ, “That backs up throughout the hospital and to emergency departments, and if they’re full, there’s pressure on them because there’s nowhere for new patients coming in by ambulance.”

Rory O’Connor, chair of council of the College of Paramedics, says that although data are collected from England, long waiting times are reflective of all parts of the UK. “Overwhelmingly, the main problem is social care in the community and flow through the hospital.”

How bad is it?

Three ambulance trusts declared critical incidents in the week leading up to Christmas 2022,5 but the problem predates such headline grabbing situations. In a statement made in July last year, managing director of AACE, Martin Flaherty, said that the NHS ambulance sector was “operating at the highest level of four within their local resource escalation action plans, normally only ever reserved for major incidents or short term periods of unusual demand.”6

AACE says most trusts are still operating at this level and have been for the past year or two. “We are not aware of any other sector that is required to operate in this way because of commissioned resource levels not meeting demand.”

But perhaps the starkest evidence of impact is the stories of patient deaths linked to ambulance delays in the national and local press throughout 2022.7 In early December the president of the Royal College of Emergency Medicine (RCEM), Adrian Boyle, estimated that problems with urgent and emergency care had contributed to around 225 excess deaths the previous week.8 AACE’s latest figures, from November 2022, estimate that around 39 000 patients experienced potential harm as a result of long handover delays in that month, with around 4000 of these experiencing severe harm.9

How is this affecting ambulance staff?

Morale—long a cause of concern with other NHS staff10—has sharply deteriorated, according to the latest NHS staff survey.11 Compared with 2020, in 2021 staff in ambulance trusts were 10 percentage points less likely to look forward to going to work or be enthusiastic about their job. The rate at which ambulance staff are leaving their roles has more than doubled in the past decade.6

Long term operation at what should be short term escalation levels has a wider impact. “Mandatory training for staff, clinical refresher training, personal development—all these activities cease,” says AACE, “Trusts would also typically redeploy all clinically trained staff from other positions in order to increase resourcing levels.”

The strikes held across England and Wales in December 2022, and scheduled to continue in 2023, are the culmination of ambulance worker frustrations. AACE says, “We’re getting an increasingly high number of paramedics and other ambulance service employees requiring support for their mental health, which is in part attributable to the challenging working conditions and their inability to deliver the quality of care they want for patients.”

What attempts have been made to solve the ambulance crisis?

Efforts to decrease journeys are being made, with more “hear and treat” (dealing with patients over the phone) and “see and treat” (treating patients in the home and not transporting them anywhere) services being deployed. According to the latest national ambulance data report, for November 2022, there were 985 000 hear and treat incidents in the 12 months to November 2022—a 6% increase on the previous year8—although the volume of see and treat incidents declined over the same timescale. But, says AACE, although they’re taking fewer patients to hospital year on year, response times are not improving because ambulances are being held up at hospital.

Last September, St John Ambulance was commissioned to provide an “auxiliary” ambulance service of at least 5000 hours a month “national surge capacity,” in a contract worth up to £30m over four years.12 The continuing target breaches suggest, however, that this is far from enough.

Longer term, solutions are complicated because they are wrapped up in problems endemic in the NHS, which have led not just to ambulance strikes, but also to nurse strikes, and possible junior doctor strikes.13

What do NHS bosses say about the crisis?

NHS England declined a request for interview with The BMJ for this article.

In a winter resilience plan published in August 2022, NHS chiefs said, “We have provided extra funding to ambulance services, offered intensive support to those trusts most challenged by ambulance delays, and rolled out virtual wards across the country, enabling patients who would otherwise be in hospital to get support at home.” September saw an update on these plans, including continuous system control centres to oversee demand and capacity by tracking beds and attendees, and expanding fall services, which NHS chiefs said could free up around 55 000 ambulance trips. Integrated care systems were expected to collaborate with care homes to ensure access to avoidable admissions initiatives and other services.14

What other possible solutions could there be?

AACE says, “We would like to see hospitals that experience consistently lengthy delays and have ambulances queuing outside their emergency departments proactively learning from hospitals that do not have these problems, and to consider what immediate measures they can take to reduce their handover delays.”

Alongside RCEM, they have recommended hospitals introduce flow measures to reduce bottlenecks at emergency departments. “This could improve flow through the hospital by cohorting their medically fit for discharge patients, moving them off wards into an area where they can be suitably and safely monitored, and where fewer resources are required.”

A “continuous flow model” or “proactive flow model,” in which patients are transferred from the emergency department into wards whether or not beds are available, is being trialled by some trusts, such as Bristol.15

Boyle says that hospitals should consider the model given the huge pressure on emergency departments and the ambulance handover delays. “RCEM has always argued that if you spread the risk across the whole patient pathway you dilute it.”

He points out that this may not work in every setting, as hospitals vary enormously in their estate and how their flow models work. “However, the risks in emergency departments are so significant at the moment—and that has knock on effects in the ambulance service—that it is beholden on people to at least consider an attempt and try this,” he tells The BMJ.


  • Not externally peer reviewed.

  • Competing interests: None.