Independent report

Chapter 10: improvements in care of COVID-19

Updated 10 January 2023

Introduction

The introduction of a novel disease with rapid transmission and severe sequelae will always be a significant challenge for the health and care sector to adapt to, and in this pandemic health and care staff have gone to extraordinary efforts to confront those challenges. In this pandemic, as with other new health threats, rapid innovation by clinicians and spreading of new best practice steadily improved outcomes. We would like to pay tribute to all those people who worked under significant pressure to deliver care and to innovate. Formal studies are the gold standard of evidence-based care but much of the initial reduction in mortality and improvement in delivery of care was in advance of these. Without their contributions many thousands more may have died.

Innovation occurred and spread through the NHS, public health and the wider health and social care sector by several routes. For clinical management, initially the sharing of contemporary best practice by clinicians and scientists from countries hit early in the pandemic, including from China, Singapore and Italy, allowed the early management of people with COVID-19 in the UK to be based on some prior knowledge. Clinical trials and formal observational studies were launched in the UK at almost the same time the first cases were imported. While these provided the most robust testing of drugs and other interventions, clinicians adapted rapidly as they observed patients’ progress and learned.

Examples where clinical practice changed early in advance of formal trials include:

• the recognition of the high rates of pulmonary embolism and substantial use of empiric prophylactic and therapeutic doses of anticoagulants
• a systematic approach to the use of high flow oxygen therapy (including the continuous positive airway pressure (CPAP) approach) based on oxygen levels
• the regular adoption of proning in intensive care units (ICUs)
• a move away from mechanical ventilation
• the identification of several distinct COVID-19 related syndromes

Later in the pandemic the syndromes of ‘long COVID’ and paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) in children were recognised. As major observational studies like SARS-CoV2 immunity and reinfection evaluation (SIREN) and the COVID-19 Clinical Information Network (CO-CIN) and then therapeutic trials including the Randomised Evaluation of COVID-19 Therapy study (RECOVERY) started to publish, change in clinical practice was increasingly and rightly driven by formal scientific methodologies and outcomes. The NHS and equivalents across the UK were relatively systematic at insisting that novel treatments were used in formal trials where possible (see Chapter 9: pharmaceutical interventions: therapeutics and vaccines). The importance of initial changes in practice as clinicians in the UK and globally learned and adapted to a new disease and shared best practice, however, should not be underestimated and may have contributed significantly to the fall in mortality of cases between the first and second waves.

There was also widespread and rapid change to the delivery of care. This included:

• ventilation and ICU care expanding widely outside its normal footprint in hospitals, with whole floors being taken over for care of severe COVID-19 patients
• the move of specialists to completely different areas of work
• new ways of delivering care at home, in the community and remotely
• a substantial increase in telemedicine
• the construction of additional hospital capacity (in England called ‘Nightingale’ hospitals)

Infection prevention and control (IPC) also evolved during the pandemic as the epidemiological situation changed, other elements of the response came on-stream and new evidence emerged. For example, changing case definitions and limited testing in the first 3 months of the pandemic made it challenging for healthcare settings to identify and confirm cases and therefore to put appropriate IPC precautions in place. The first few cases were managed according to high consequence infectious disease (HCID) protocols but, as numbers of patients with COVID-19 in hospital and community spread occurred, proportionate and deliverable care throughout health and care settings was essential. During the first wave, nosocomial transmission was a particular concern as healthcare settings worked to manage surging demand while rapidly identifying cases and implementing relevant IPC actions in response. Limited testing early in the first wave complicated this picture but, as testing capacity grew and IPC guidance adapted in response to the changing situation, nosocomial transmission reduced.

This chapter outlines changes to clinical care, changes to delivery of care and finally changes in IPC. There are of course many important operational considerations here, many of which are outside the remit of the CMOs and GCSA and beyond the scope of this report. Some operational matters – for example, regarding health system response – are set out below for context, but this account is by no means exhaustive. We anticipate public inquiries will give a more complete overview of health system responses and improvements in care across the 4 nations, and set out where the key lessons learned are.

Clinical practice evolution

In the first 2 months of the pandemic, when only a small number of known COVID-19 cases had entered the UK, health services adopted existing HCID protocols to prevent any transmission risk within healthcare settings, delivering support to a small number of cases in highly specialised settings. The aim was to prevent any spread from known cases while optimising care for the patients involved. This is likely to be the priority for the first cases of any new pandemic or epidemic as it serves several purposes:

• it contributed to delaying the establishment of the pandemic
• it allows knowledge and experience of clinical management to accumulate in specialist centres which can then be disseminated
• it provides assurance to the public that these cases are less likely to transmit at a time of very high concern

There are, however, a limited number of HCID beds and this will only be a realistic response when numbers needing hospitalisation are small and community transmission is limited. Clinical management in HCID units was based on existing knowledge of broadly similar diseases, as well as emerging evidence from outbreaks and case reports across the world.

As cases began to rapidly rise following widespread seeding of cases in the community leading to the first wave, health services saw a surge in needs across the population as high volumes of COVID-19 patients presented to healthcare settings. At this point it was necessary simultaneously to:

• manage rising demand alongside existing health needs
• reduce transmission risk within healthcare settings
• rapidly scale up clinical care for a cohort of patients with a variety of care requirements, including for intensive care

Routine and non-urgent services were paused and care for COVID-19 patients with urgent and extensive needs prioritised. At this point, the disease was still relatively new and evidence on appropriate clinical care still emerging. Oxygen delivery was a priority. As the wave progressed, clinicians rapidly developed and shared best practice, including on the importance of proning, anticoagulation and effective use of high-flow oxygen guided by pulse oximetry. Again, this accumulation of clinical experience is likely to be replicated in any new pandemic or novel epidemic.

Following the first wave, formal evidence based on studies and then trials of effective pharmaceutical interventions began to emerge and was implemented rapidly and effectively. So, too, did approaches to IPC and the balance of transmission risk with the impact of highly specified IPC guidance on service delivery. The broader management of healthcare services also adjusted and routine and non-urgent care was then expanded alongside continuing support for COVID-19 patients. Delivering this wider range of services alongside rising case rates in the second wave put huge pressure on health services and professionals, and there was a continuing need to support workforce morale.

At the same time, an improved understanding of COVID-19 and shared developments in clinical practice, alongside available therapeutics, helped manage this second wave in clinical settings. The impact of the second wave on non-COVID-19 care was smaller, despite larger numbers of cases because of this adaptation.

As the pandemic and subsequent waves progressed and the seroprevalence of the population rose through a combination of vaccine rollout and infection-derived immunity, rates of severe disease reduced, and clinicians became increasingly familiar with management of COVID-19 as part of regular practice. They also increasingly saw patients with COVID-19 who were in healthcare settings with, rather than due to, the disease. Being able to distinguish between the 2 was important not only for clinical management but also national surveillance of severe disease, and it was difficult to achieve in a timely way.

Throughout the pandemic, health and care staff have gone to extraordinary efforts in highly pressured environments to deliver care and protect patients and colleagues, even when this presented potential risk to their physical and mental health, and the impact on morale has been considerable. Support has been important – from the public, from local mental health support offers, by adapting services to manage surges, and most importantly by wider efforts to reduce infection rates in the community. Research – from early case studies to wider network intelligence such as through CO-CIN, to large clinical trials – has been critical. Emerging evidence has informed guidance and clinical practice, alongside shared expertise as clinicians have developed and shared new ways to treat and support patients with COVID-19 through local groups and clinical networks.

There has been a continual evolution during this pandemic: in clinical management, managing surges in demand alongside competing healthcare priorities, and in IPC practices. The rest of this chapter sets out these processes in more detail.

To inform this chapter, we discussed experiences with the royal colleges of physicians, general practice, intensive care, emergency medicine, psychiatry, obstetrics and gynaecology and the Faculty of Public Health. We had discussions with trainees and consultants from these specialties. All specialties have been important to the response in different ways, and it was a critical part of our role to link into a range of specialties and understand their experiences.

Weekly discussions with the Academy of Medical Royal Colleges (AoMRC) throughout the pandemic have been seen both by the royal colleges and the CMOs as invaluable in highlighting issues, innovations and pressure points across the professions as the pandemic evolved. Of course, there were many differences in the experience of different specialties, and indeed of individuals within specialties. Which areas come under what types of pressure may also look different in a future pandemic depending on the pathogen itself, health and social care structures and the population’s health characteristics.

People working across health and social care have been critical to this pandemic, including public health teams, other keyworkers and those working in community and voluntary sector organisations, as well as recognised health and social care professionals. As CMOs, however, we were professional leaders for doctors – and so we focus on healthcare settings and healthcare professionals (particularly doctors) in this section. Here, we have focused on reflections from our collective professional leadership role rather than from the perspective of directing the health system response.

It is worth noting that these issues were complex and rarely have a single answer, and as a consequence collective leadership of the medical profession and shared decision-making has been an important part of the response.

The clinical trials infrastructure in the UK and the rapid enrolment of patients into trials even at the height of the pandemic provided essential evidence that improved clinical care in the UK and globally. From March 2020 to March 2021, the National Institute for Health and Care Research (NIHR) Clinical Research Network supported recruitment of over 1 million patients from across the UK into urgent public health studies.^{[footnote 1]}

Patient care

In the first weeks of the pandemic, little was known about COVID-19, with correspondingly limited treatment options beyond the use of oxygen and respiratory and general systems support. Clinical understanding rapidly assimilated; early case reports and data from countries further ahead in their first wave (Wuhan, then wider China and Northern Italy) were hugely important in identifying the disease phenotype, progression, multisystem involvement, and outcomes. This learning was supplemented within weeks with practical experience from rapidly increasing case numbers within the UK.

Learning was rapidly disseminated through informal and formalised networks so that regions already experiencing high volumes of patients could share their learning with others further behind in the wave. Clinicians and early case reports drove changes in clinical practice that improved care in wave 1 far ahead of formal observational trials (wave 2), clinical trials (wave 3) and the deployment of specific pharmaceutical interventions and vaccinations (see Chapter 9: pharmaceutical interventions: therapeutics and vaccines).

Observational studies such as the International Severe Acute Respiratory and emerging Infection Consortium (ISARIC) and SIREN (which are explored in Chapter 1: understanding the pathogen and Chapter 9) provided evidence during the early stages of the pandemic, months ahead of results from formal clinical trials.

In-hospital mortality rates, which peaked in the earliest months of the pandemic, declined towards the end of the first wave, further decreasing in subsequent waves. While this reduction can, in part, be attributed to a changing patient demographic (due to shielding of susceptible at-risk patients), accumulating immunity and easier access to testing and medical advice, increased clinical familiarity and improved clinical management also demonstrably improved outcomes, with ISARIC analyses suggesting that one-fifth of the reduction in in-hospital mortality in the first wave could be accounted for by changes in treatment (optimum respiratory support and later, steroid treatment).^{[footnote 2]}

Clinical learning about COVID-19

First wave

Acute hypoxaemic respiratory failure was almost universally seen in severely unwell patients with COVID-19, with senior clinicians describing “a lifetime of acute respiratory distress syndrome (ARDS) patients in 2 years”. At the start of the first wave, there was an emphasis on early intubation for the sickest patients, with differential ventilator management practices based on different presumed phenotypes.^{[footnote 3]} However, international experiences in Lombardy and China reported high mortality in patients requiring invasive mechanical ventilation and highlighted the potential risk that ICU capacity might be exceeded.^{[footnote 4]}, ^{[footnote 5]}, ^{[footnote 6]}

In addition to increasing national ICU capacity approximately 3-fold by a number of measures, consideration of non-invasive respiratory support strategies such as CPAP and high-flow nasal oxygen (HFNO) was therefore central to reducing the need for tracheal intubation and invasive ventilation, both to reduce pressures on ICUs and as a potential strategy to reduce mortality.

High rates of failure are reported when treating other viral or bacterial pneumonias with non-invasive ventilation, leading to concern that similarly high failure rates might be observed in patients with COVID-19, with treatment delaying intubation and mechanical ventilation (rather than preventing it) and exacerbating lung injury.^{[footnote 7]} Over time, however, the approach of delaying intubation for a trial of non-invasive ventilation became a routine part of practice in many centres with general success.

A key component of respiratory support soon became the widespread use of prone positioning of mechanically ventilated patients, a strategy which already had an established evidence base for non-COVID-19 ARDS in ventilated patients.^{[footnote 8]} Informed by this pre-COVID-19 evidence base, anecdotal reports of improved oxygenation and ventilation in COVID-19 patients and, later, formalised guidance, the approach was also extended to include conscious non-ventilated patients. In some ICUs, the volume of patients requiring this management led to the development of ‘proning teams’ of redeployed staff to reduce workload on ICU staff, standardise the process and maintain patient safety.

While COVID-19 is primarily a respiratory disease in most patients, in the early weeks of the pandemic there was increasing recognition that severe COVID-19 is a complex multisystem disease involving immunological, coagulation, renal and cardiovascular systems. Severe disease requiring ICU admission might therefore present with respiratory failure alone, or with multi-organ impairment or failure, each adding to the burden on ICUs.

The exaggerated immunological response observed was characterised by hyperproduction of proinflammatory cytokines in the most severely affected patients, typically in the second week of their illness. This was closely associated with capillary leak syndrome, disseminated intravascular coagulation, ARDS, and multi-organ failure, ultimately leading to death in the most severe cases.^{[footnote 9]}, ^{[footnote 10]}

Despite initial understandable concern based on experience with SARS-CoV-1 and MERS-CoV that broadly acting immunosuppressant drugs might impair immune responses, dexamethasone was extensively trialed in hospitalised patients during the first wave as part of the RECOVERY trial.^{[footnote 11]} Less than 6 months after the first UK case, based on trial evidence, dexamethasone was approved for immediate widespread use in hospitalised patients with requirement for supplemental oxygen, substantially reducing morbidity and mortality in second and subsequent waves of the pandemic.

A further component to the multisystem disease observed by clinicians early on in the pandemic was the increased incidence of acute kidney injury among patients hospitalised with COVID-19, which had also been reported in Wuhan.^{[footnote 12]}, ^{[footnote 13]} This association was particularly pronounced in the first wave, where more than 25% of patients admitted to critical care required renal replacement therapy (RRT), with very high mortality (80%).^{[footnote 14]} In the first wave, in many ICUs it was the availability of RRT (machines and disposables) rather than ventilators that was most challenging in terms of equipment provision. Improved understanding of the disease and less restrictive fluid management strategies likely contributed to this becoming less of a challenge as the pandemic waves progressed.

The acute inflammatory state seen in COVID-19 probably led to the increased risk of thromboembolic events that was a feature of severe COVID-19, and, to a lesser extent, bleeding. This presented as both micro and macro thrombotic phenomena, with up to a third of patients admitted to ICU experiencing thromboembolic events.^{[footnote 15]} Enhanced thromboprophylaxis was rapidly introduced for patients identified as being at risk. However, even with heparin prophylaxis as standard, pulmonary thromboembolism was identified in about one-quarter of COVID-19 patients admitted to ICU, with deep vein thrombosis also observed in one-quarter of patients with pulmonary thromboembolism.^{[footnote 16]}

Cardiovascular compromise was a further challenge of the multisystem disease seen in severe COVID-19 with cardiomyopathy, myocarditis and arrythmias all contributing to advanced cardiovascular support being required for 1 in 3 patients requiring mechanical ventilation.^{[footnote 17]}

By the end of the first wave, the management of hospitalised patients had evolved significantly. Seriously unwell patients were often trialed on non-invasive rather than invasive ventilation, hypovolaemia was avoided, enhanced thromboprophylaxis provided as standard for at risk patients, and many were randomised to receive dexamethasone.

Second and third waves

By the start of the second wave, dexamethasone was in widespread use. As the pandemic progressed in the second and third waves, evidence from other clinical trials mounted, filling in gaps that could not be met by observational studies and clinical networks. As a result of these trials, many patients who were hospitalised during the third wave were also treated with more targeted drugs including small molecule directly acting antivirals and monoclonal antibodies which further improved clinical outcomes, albeit with a smaller, more incremental effect (see Chapter 9: pharmaceutical interventions: therapeutics and vaccines). It was important that in the UK use of unproven medicines outside the setting of a clinical trial was effectively minimised.

Clinical trials also partially addressed the absence of evidence to support the novel widespread use of different modalities of non-invasive ventilation, which had resulted in significant variability both in international guidelines and clinical practice during the first and second waves. The UK RECOVERY-Respiratory Support trial found that an initial strategy of CPAP significantly reduced the risk of tracheal intubation or mortality compared with conventional oxygen therapy, or HFNO in patients with acute hypoxaemic respiratory failure, and provides some support to this approach.

Widespread immunisation, with some additional accumulation of immunity due to prior infection, was the major factor in reducing the number of patients requiring ICU admission for severe COVID-19, with numbers needing ICU falling substantially in spring 2021. However, throughout 2020 to 2021, COVID-19 remained a severe disease for many, with some patients requiring ICU admission and prolonged care on ICU, and with high associated mortality rates. Despite improvements in understanding of the disease and the introduction of specific therapeutics, for those patients who required tracheal intubation and ventilation, multi-organ support was typically required. Duration of ICU care for such patients typically lasted several weeks, perhaps 5 times the typical stay of many ICU patients and mortality remained close to 1 in 2 patients.^{[footnote 17]}

Understanding of rare and delayed sequelae

Understanding of disease management evolved with the progression of the pandemic, as did recognition of rarer and/or delayed or long-term sequelae of COVID-19 infection. A diverse number of chronic symptoms were reported by approximately 2% of the population weeks or months after their initial acute infection. ‘long COVID’ encompassed multiple symptoms (and, it is thought, syndromes), and the disabling symptoms experienced by some patients challenged their ability to return to normal life. Long COVID likely includes a combination of conditions including organ damage by severe or milder COVID-19 infections, perhaps disease caused by persisting infection, persistent clotting and more traditional post-viral syndromes. Research into the causes, pathophysiology and management of this disorder is ongoing, with recognition and understanding improving over time. However, currently prevention (through vaccination) represents the only evidence-based approach to the condition.

While children make up a very small proportion of COVID-19 hospitalisations and deaths, several countries reported an increased number of children with symptoms similar to Kawasaki disease (KD) and toxic shock syndrome (TSS) in the early months of the pandemic. Prospective enhanced surveillance led by the British Paediatric Surveillance Unit and Public Health England (PHE) demonstrated a strong association between this condition and SARS-CoV-2, with children developing KD or TSS symptoms with single or multi-organ failure several weeks after initial COVID-19 infection. While very rare, PIMS-TS is the most severe recognised complication for children, with 42% of 268 cases detected during the first wave of the pandemic requiring ICU admission, though mortality was relatively low at 1.1%.^{[footnote 18]}

A signal of increased incidence of myocarditis and pericarditis in younger people following COVID-19 infection in younger people was also observed several months into the pandemic, and subsequently also identified following COVID-19 vaccination, albeit much less commonly (commensurate with other routine vaccinations).^{[footnote 19]} While the great majority of cases were mild and self-resolving, nuanced accurate communication of these risks (and thus the relative protection conferred from vaccination) was required in the face of evolving evidence. While in the early months of the pandemic infection in young people and children had been relatively mild with sequalae rarely observed, emerging evidence of PIMS-TS, myocarditis and pericarditis, and long COVID altered the risk-benefit balance in these groups, impacting decision-making regarding transmission and prevention of infection (for example, Joint Committee on Vaccination and Immunisation and CMO vaccination recommendations).

Measures to manage surging clinical needs

Early in the pandemic, the NHS wrote to all staff initiating the “fastest and most far-reaching repurposing of NHS services, staffing and capacity in our 73-year history”.^{[footnote 20]}, ^{[footnote 21]} Efforts to meet surging demand throughout the pandemic included:

• the re-prioritisation of healthcare services
• expansion of capacity and equipment
• a shift to remote working for primary care and outpatient services
• substantial transfers of patients (particularly in winter 2020 to 2021)
• perhaps most importantly, large-scale redeployment and upskilling of staff

This section sets out how that process evolved over the pandemic to meet surging clinical needs and enable the health system to ramp up support.

Re-prioritisation of healthcare services

At the outset of the pandemic, when cases were rapidly rising and it was not clear what and when the peak would be (even with control measures in place), services were reprioritised. Owing to both the wider impacts of the pandemic and efforts to reprioritise services to meet surging demand, non-COVID-19, non-urgent care services, including elective operations and screening, were impacted.

The public were encouraged through widespread public communications to avoid healthcare settings unless their care needs were urgent and necessary, and not to present in healthcare settings if they had COVID-19 symptoms.

Alongside this, processes were set up to assess people for COVID-19 before presenting in-person at healthcare settings, such as the network of COVID-19 assessment centres set up in March 2020 in Scotland to assess and treat potential COVID-19 patients in the community. Emergency admissions, urgent cancer treatment and other clinically urgent care was largely maintained.^{[footnote 22]}

Reprioritisation impacted demand differently across different areas of the health system. Primary care presentations, for example, reduced considerably in the first wave. At the same time, intensive care saw rapidly rising patient numbers and required surge staffing. Hospital emergency admissions were 56% lower in April 2020 than April 2019 as healthcare-seeking behaviour changed, some incidents prompting emergency care reduced (such as sporting and traffic accidents), and healthcare provision shifted to online consultation where possible.^{[footnote 23]} This reduction will have included some who needed urgent care but did not seek it, often for altruistic reasons.

From an early stage it was recognised that advice to avoid unnecessary visits to healthcare could discourage necessary health-seeking behaviours, and so there were early communications reiterating that urgent and necessary health services remained open and encouraging their use. However, there were reports particularly during the first wave of people avoiding health services in an effort to both reduce demand on the health service and manage their own risk of infection with SARS-CoV-2. This is an important point to consider for a future pandemic.

As both therapeutics and vaccines became available, reducing the risk of severe disease associated with SARS-CoV-2 infection, non-COVID-19 and non-urgent services were stepped back up. Between waves, routine non-urgent elective care was offered, while maintaining critical care surge capacity for further waves.

This rapid re-prioritisation of healthcare services enabled the NHS to continue to support COVID-19 patients. However, there was an ongoing need to balance this with other health needs that continued to require services, such as non-communicable diseases or pregnancy-related care.

Expanding ICU and acute bed capacity and equipment

The major focus early in the pandemic was on expanding ICU capacity (staff, space, systems and equipment) both within the existing health estate and beyond. This included repurposing theatres and later taking over other general wards to drive up critical care space, alongside efforts to expand the workforce and equipment outlined below.

In England, for example, between 17 March and 12 April 2020, the number of available critical care beds increased from 12,600 to 53,700.^{[footnote 24]} Expansion of critical care capacity was achieved through:

• urgently discharging all medically fit patients
• providing governmental funding of discharge packages to support the supply and resilience of post-hospital care
• postponement of non-urgent elective operations
• pausing a number of screening programmes
• block-buying capacity in independent hospitals

Routine procedural ‘burdens’ (such as routine Care Quality Commission inspections in England) were removed to enable staff to devote maximum operational effort to COVID readiness and response.

Temporary hospitals (called ‘Nightingale hospitals’ in England) were also set up to provide surge bed capacity in the event of existing hospital capacity being exceeded. In the event, demand for beds was largely managed within the existing NHS estate, but this was not a foregone conclusion due to the extreme pressures observed in other health systems during early 2020. There may well be a similar need to manage the risk of hospital capacity being exceeded in a future pandemic.

There are important lessons from the Nightingale hospitals, such as the need to bring in additional staffing, equipment and digital infrastructure to support expansion of bed capacity. The logistic and staffing pressures of setting up a new clinical setting had to be balanced with existing staffing and system needs across the hospital estate, and the potential disbenefits of moving staff from their usual workplace where they were likely to be maximally effective. That balance was continually evolving. It was also important to ensure these hospitals were as close to existing hospitals as possible so that staff and patients could move between sites easily when needed. Finally there was a need to remain flexible when setting these up so that if they were not needed, resource could be rapidly returned to existing hospital settings.

This had never been done before at such scale since the creation of the NHS, and ICU teams and experts were key in guiding this rapid expansion. So, too, were ICU networks. In the early weeks of the first wave, pre-existing and novel networks were established to facilitate mutual aid and, in the second wave, create transfer teams staffed by ICU doctors and nurses. These teams had regular discussions to assess capacity and reduce pressure in the most severely affected regions, transferring severely unwell patients needing ICU care from hospitals with no available ICU or high dependency unit (HDU) beds to networked hospitals with more capacity. This was particularly important as the epidemic moved across the country and affected different areas at different points in time.

There was also an urgent need to surge equipment. Initially, the focus was on increasing provision of ventilators to support large numbers of severe COVID-19 cases managed in temporary ICUs. As the pandemic progressed, it also became clear that a mainstay of care involved high-flow oxygen. This required both an increase in provision of devices to deliver this therapy and a review of hospital sites to ensure oxygen supplies were not exhausted in the face of unprecedented demands on oxygen supplies. Some hospitals found existing piped oxygen capacity insufficient. Hospital estates teams played an important role in reviewing oxygen supplies capacity and hardware and maintaining safe delivery.

Supply of renal replacement machines and disposables was also a key issue for many units across the country. So, too, were consumables, such as anaesthetic drugs and renal consumables. National and regional teams supported local health services to pool equipment in mutual aid systems. They also supported the scaling up of production and procuring equipment at pace – an important process in the context of high global demand for equipment supporting COVID-19 clinical care. Repurposing equipment to different service areas was important to meet demand but had to be balanced with the risks of healthcare professionals using unfamiliar equipment.

As noted above, staffing was central to the ICU response. To expand resource, large numbers of anaesthetists and theatre staff were redeployed to ICU from theatre work and other staff were redeployed to critical care from ward-based work, bringing numbers up 2 to 3-fold. Redeployed staff were trained and cross-skilled at great pace and supervised by permanent staff. Expansion of ICU capacity led to plans for revised staff-to-patient ratios when needed, to maximise care delivery. Other staff were redeployed to independent sector hospitals to support urgent surgical work being undertaken there. As knowledge of the disease and its treatments increased rapidly, this knowledge was disseminated alongside information from NHS England and PHE through rapidly convened collaborations between critical care and anaesthesia organisations.

Evolving understanding of clinical needs also informed surge procedures – for example, the possible need for renal support or anticoagulation therapies. Continual evaluations and care improvement processes highlighted these needs throughout, and there was important learning on building surged bed capacity that incorporated the breadth of service needs.^{[footnote 25]} The National Audit Office review on surging equipment sets out some important reflections such as the benefits of scaling up existing designs when surging at pace.^{[footnote 26]}

Redeployment

To support this surge, large numbers of trainees and retired healthcare workers came forward to support colleagues at a time when there was a real concern that health service capacity could be exceeded. Over 40,000 students, trainees and learners came forward to support the surge, including medical students, student nurses, midwives and allied health professionals, and over 1.5 million people volunteered to support the NHS and social care.^{[footnote 27]}

Given the increased risks to older practitioners, the return to work by recently retired members of the profession was remarkable, and heartening. As with other recent epidemics including the West African Ebola virus epidemic and the SARS-CoV-1 epidemic when UK medical, nursing and allied professional staff volunteered to work in West Africa and Canada respectively, the courage and professionalism of staff facing an emergency, including where there is significant personal risk, has been repeatedly demonstrated.

Such mass redeployment carried with it a need to support professionals. Refresher training was offered for all clinical and patient-facing staff. There was also a need to match existing skills and experience of staff to different service contexts during redeployment. The skills and experience of a number of different healthcare professionals was vital to have the right skill mix in surge teams, and this should be properly recognised.

When redeploying staff, there was a need to rapidly match skills (rather than just head count), particularly because untrained staff could represent additional burden on existing staff in some settings. There were, however, some tasks – such as support for proning in ICU – that required minimal training. Workforce readiness for such surge needs is key – for example, with training for surge situations or cross-training between specialties.

Finally, indemnity cover and appropriate fitness-to-practice checks were needed. The UK CMOs, NHS England National Medical Director, the AoMRC and the General Medical Council (GMC) wrote to doctors stressing that it may be appropriate and necessary for clinicians to work beyond their usual disciplinary boundaries and specialisms, and that those who did so would be supported (see Appendix A), with equivalent considerations for nurses and allied health professionals.^{[footnote 28]} The GMC played an important role in ensuring those redeployed were fit to practise, and it was crucial to involve them early in discussions to ensure regulatory issues were addressed at speed. By 27 March 2020 the GMC had granted temporary registration to 11,800 doctors.^{[footnote 29]}

There were challenges in achieving this scale of redeployment, in part owing to the speed of its implementation, the around-the-clock support needed for staff and the context of rapidly changing projections of patient needs. Surging staff towards the needs of COVID-19 patients needed to be continually balanced with delivering support for other health needs, and the relative pressures on different areas of the health service had to be carefully managed.

Remote working

In the first wave, GPs and outpatient services swiftly adapted services to reduce face-to-face appointments and minimise transmission risk by offering remote consultations using video, telephone, email and text services. These changes resulted in around three-quarters of patients being managed remotely by June 2020 compared with one-quarter at the same time the previous year, with the total volume of primary care activity falling by 25%.^{[footnote 30]} Patients with symptoms that may have been due to COVID-19 were seen in dedicated respiratory ‘hot clinics’, often in the form of a dedicated hub of a network of general practices.

This move to remote working relied on the existing digital infrastructure, which within NHS primary care enabled clinicians to work remotely and access records as well as issue electronic prescriptions to patients who had often moved from their usual area of residence. It also relied on supported and digital enablement for both staff and patients. NHS 111 also provided a key role in advising patients and limiting demands on primary care and specialist services. It was, however, initially under pressure from extremely high patient requests, resulting in long waiting times.

There were limits to how far remote consultation could replace in-person services – for example, for those without digital access or with conditions such as dementia. However, early in the pandemic limits on testing capacity meant that safeguards such as pre-testing to enable face-to-face consultation were not possible (see Chapter 6: testing) and so in many cases the balance of risks and benefits still favoured remote support.

Reflections on measures to meet surging demand

Healthcare professionals were working in highly pressured environments with potential significant exposure to transmission risk for a novel and largely unknown pathogen. Particularly during surges in case rates, staff were managing transmission risk both within the workplace and at home, and many fed back that in the first months of the pandemic the fear of harm to patients, colleagues, vulnerable family members and themselves was significant.

Morale across the workforce was understandably closely linked to the overall direction of the pandemic and the broader public mood, and it was important to bear this in mind in communications. Colleagues fed back that public support and workplace mental health and wellbeing support were important to them, though this varied over time and across different workplaces.

For the UK CMOs, regular discussions across the health and care professions have aided better understanding of what was happening on the ground and how it was impacting colleagues, including those in supporting roles or shielding. It was also important to have an early view of risks to health and care workers through national surveillance of morbidity and mortality.

All of these issues required significant operational and clinical expertise.

There was a careful balance to strike in updating guidance on clinical practice while services were busy surging staff, beds and equipment. Routine is important to maintain safety in clinical care, and each change to guidance interrupts this and can cause confusion and therefore potentially risk. At the same time, evidence was emerging every day on best ways to manage COVID-19 cases and there was a need to respond to this. There was and remains debate across the health professions on the appropriate point at which evidence is strong enough to change practice, particularly when pre-prints were bringing (often very important) evidence into the public domain well ahead of peer review. Clinicians fed back to us that being clear on the scientific or operational rationale for a change, and keeping guidance as simple as possible, was helpful to them.

There was a need to balance the need for surge and service adjustment to meet pandemic needs with maintaining an appropriate level of care and support for other health needs. This evolved over the course of the pandemic – for example, changing to allow birthing partners to attend births or enabling access for advocates of those with a learning disability when wider visitor restrictions were in place.

Shifting to remote consultations, discouraging unnecessary health setting presentations and asking that those with specific symptoms avoid healthcare settings unless necessary has been an effective way to reduce potential transmission risks and additional burden during a time of significant pressure. However, this must be balanced with a risk that health-seeking behaviours were adjusted to such a degree that there was significant unmet need, with resulting impacts on mortality and morbidity.

Additionally, advice discouraging presentation in healthcare settings when people had certain symptoms needed to include caveats and routes for appropriate triage where these symptoms were not highly specific. Without this, there was a risk that people with other conditions with a similar presentation (for example, other febrile infections) were discouraged from accessing the healthcare they needed even though they did not present a threat of SARS-CoV-2 transmission.

Communications to discourage unnecessary visits to healthcare settings therefore needed to be continually adapted and revisited if such issues arose. UK CMOs stressed in public communications that emergency care was always open for business, but emergency presentation rates were much lower than normal during the first wave. Undoubtedly some people who would (and could) have come forward did not because of a sense of altruism or perceived risk of being in hospital.

There is little doubt that delays in presentation, reductions in secondary prevention (such as statins and antihypertensives), postponement of elective and semi-elective care and screening will have led to later and more severe presentation of non-COVID illness both during and after the first 3 waves. The combined effect of this will likely lead to a prolonged period of non-COVID excess mortality and morbidity after the worst period of the pandemic is over.

Infection prevention and control

Context

IPC is a vital patient safety consideration across health and social care interactions. Its importance has been especially evident through the COVID-19 pandemic, with an increased focus on IPC practice not just in health and social care, but across the breadth of community settings (schools, prisons and places of detention). Here, we focus on COVID-19 IPC measures in healthcare settings and set out how IPC guidance evolved during the pandemic, where the evidence base has progressed, and finally our reflections.

The IPC guidance for COVID-19 was developed by the 4 UK nations. This supported consistency in practice and a shared understanding of the scientific evidence across the UK. For wider transmission control measures, see Chapter 8: non-pharmaceutical interventions (NPIs). For measures (including IPC) in educational settings and care homes, see Chapters 8.1 and 8.2 respectively.

The aims of the COVID-19 IPC guidance were to reduce the transmission of SARS-CoV-2 in health and care settings, protecting patients, staff and visitors, while supporting the safe delivery of health and care services. This guidance was produced in the context of an evolving evidence base, with clinical practice adapting in response to emerging health needs, which required the following considerations to be taken into account:

1. Emerging evidence on transmission risks for SARS-CoV-2, which initially was often based on rapid assessments of real-world scenarios and inevitably featured variations in methodology and outcomes.
2. International recommendations regarding best practice in IPC. These built on the established evidence base for IPC practices derived in particular from the World Health Organization (WHO). IPC guidance in the UK was initially based on amended Department of Health and Social Care (DHSC) UK pandemic flu guidance but was adapted throughout the pandemic in accordance with emerging evidence, expert recommendations (such as from UK Scientific Advisory Group for Emergencies (SAGE) and subgroups) and changes in the epidemiology of SARS-CoV-2.^{[footnote 31]}
3. The evolving healthcare situation in the UK. The COVID-19 IPC guidance developed over the course of the pandemic to reflect these changes, moving from initially focusing on managing COVID patients during the first wave to balancing this with supporting the safe restoration of NHS services from mid-2020 onwards, such as through establishment of risk-based clinical pathways.
4. Ensuring that guidance was consistent with established IPC practice and easily understood by staff and implementable in all health and care settings.
5. The impact of IPC guidance on workforce morale, to support and reassure clinicians who were responding to a novel virus and were concerned for the safety of their patients, colleagues, families and themselves.

These are complex issues with inherent tensions between them. At a national level, strong relationships between organisations across the UK ensured that these tensions were discussed and consensus, evidence-based IPC practice was reflected in the UK COVID-19 IPC guidance. This collaboration brought broad consistency of approach across the 4 national health and care systems. Collaboration and co-operation with external stakeholders, such as the AoMRC, the Health and Safety Executive and ventilation experts, added additional expertise (and credence) to the COVID-19 IPC guidance and over time contributed to increased certainty and standardisation of approach across the system. There was, however, never complete consensus across all professional groups and we consider this is likely to be a feature of any future pandemic as well.

Continual evidence reviews were undertaken by the UK public health bodies to identify changes in the evidence base for IPC interventions and reflected in updated guidance, to provide assurance to all stakeholders that the full range of evidence was being assessed. Creating a systematic and consolidated way of communicating this knowledge from the 4 UK health systems’ specialist IPC advice to all frontline workforces was vital, and not always easy. This was done via regular webinars with directors of nursing and directors of IPC in providers, as well as specific communications materials to support implementation of IPC measures. Again, 4-nation alignment on this was important.

Many of the IPC measures recommended across the NHS for COVID-19 were known and established IPC practices:

• standard infection control precautions (SICPs)
• transmission-based precautions (TBPs)

The COVID-19 IPC guidance, as well as outlining when and where SICPs and TBPs should be used, contained a number of specific measures for COVID-19 such as universal masking for source control, COVID-19 specific treatment pathways and physical and social distancing within healthcare settings. There was also an added emphasis on the use of a hierarchy of controls approach, which encompasses a risk assessment of the effectiveness of potential interventions in individual contexts including consideration of the environment, the patient and the healthcare practitioner.

Together these approaches brought together 3 critical system components: clinical care for patients, IPC, and assessment and management of risks. In addition, the Personal Protective Equipment (PPE) Innovation and Sustainability group and NHS bodies collaborated to develop an educational programme on the safe use of non-sterile gloves, appropriate respiratory protective equipment (RPE) fit testing, and the assessment of novel PPE.^{[footnote 32]}

Evidence

The IPC guidelines were initially informed by experience and evidence of responding to the risks posed by other pathogens, including respiratory infectious diseases (notably, influenza). There is good evidence regarding the effectiveness of SICPs and TBPs to prevent and control the transmission of known pathogens if applied correctly.^{[footnote 33]} The COVID-19 IPC guidance built on this evidence base and added specific measures based on the evidence of the transmission and impact of SARS-CoV-2, such as universal masking in healthcare settings and patient cohorting.

COVID-19 IPC measures were implemented while the epidemiology of the pandemic was changing (for example, emergence of variants of concern, the introduction and effect of population-level public health mitigations, and the availability of licensed vaccines and therapeutics). There was continual adaptation of measures in response to epidemiology and wider measures in place and use of the hierarchy of controls approach to risk assessment across different settings and services.

It is widely accepted that it is very difficult to assess the effectiveness of individual IPC interventions in this context, due to the multi-interventional nature of IPC practice and widespread community transmission during the pandemic response. However, evidence suggests that the application of the established IPC practices was effective in markedly reducing the transmission of SARS-CoV-2 in healthcare settings across the UK.^{[footnote 34]} The evidence (anecdotal and published) also suggests that the effectiveness of IPC practice in preventing transmission was related to their optimised application in the healthcare environment.^{[footnote 35]}

Universal masking (source control) with face coverings or surgical masks (type II or IIR) to prevent the transmission of SARS-CoV-2 and other respiratory infectious agents was implemented in healthcare settings from 15 June 2020. There is evidence to suggest that this intervention was effective in reducing transmission of COVID-19 in the healthcare environment, though importantly as part of the hierarchy of controls and considering possible associated risks if not properly managed.^{[footnote 36]}

It was also important to consider inappropriate use of PPE, the role of other factors such as ventilation or crowding (particularly in high throughput departments), and the potential inability or unwillingness of patients to wear masks.

Physical and social distancing were also applied to healthcare settings in response to the pandemic and were reported as being effective in preventing transmission.^{[footnote 37]} Similarly, COVID-19 management pathways (segregating infectious from non-infectious patients, typically via cohorting) were also implemented across the system and have been reported as being effective at mitigating the risk of transmission posed by the SARS-CoV-2 pandemic.^{[footnote 38]}

A computational modelling approach was used to determine the effectiveness of IPC interventions in England in the first wave of the pandemic.^{[footnote 39]} Outputs derived from this model estimated the most effective interventions for the prevention of nosocomial COVID-19 infections in patients to be decreasing occupancy, increasing spacing between beds, and testing patients on admission. Universal mask use was found to be the most effective single intervention for preventing transmission among healthcare workers, although importantly it was the collective impact of all interventions that demonstrated greatest effects. The study found that interventions introduced over the first wave of the SARS-CoV-2 pandemic in England probably reduced healthcare worker infection rates by around 51% (95% confidence interval 43.6% to 55%), with authors estimating that without IPC interventions, nosocomial COVID-19 infections in patients could have been 5-fold higher (5.2% versus 1% of susceptible inpatients).

Importantly, it was difficult to separate aerosols generated by natural respiratory activities, such as coughing, from those generated by procedures. This evidence supported the removal of several aerosol generating procedures (AGPs) from the AGP list in England and Wales, including some oxygen modalities such as high flow nasal oxygen, non-invasive ventilation and manual facemask ventilation.^{[footnote 40]}

Reflections on IPC

At the outset of the pandemic, scientific knowledge of COVID-19 was unavailable, which led to widespread anxiety across society. At the same time, decisions were required about what IPC measures were needed to protect staff, patients and visitors in health and care settings, taking a wide range of considerations into account. Balancing these considerations was a complex process for healthcare leaders, but also for professionals across the healthcare sector who worked extremely hard continually to balance multiple risks throughout this pandemic, including to themselves and their families as well as patients, in order to deliver the best achievable quality care.

Clinicians were understandably concerned that IPC practices and resources should not only protect them from becoming infected at work and subsequently lead to the risk of infecting their patients, but also be appropriately tailored to the levels of risk in different settings and for different activities. Recommendations in IPC guidance were always made using the best available evidence. However, undeveloped supply chains meant that PPE supplies came under widespread pressure due to increased demand and required prolonged use and in some cases re-use of PPE. This is likely to be repeated in the initial stages of future pandemics and epidemics and should be anticipated.

Especially in the early stages of the pandemic there was widespread concern in some professional groups that IPC measures being recommended were insufficient, based in part on a concern it was being driven by supply constraints rather than science. There were also vigorous debates about what constituted an AGP requiring higher levels of IPC. This was probably the biggest source of tension within the otherwise largely unified healthcare professions in the initial months. Concerns about whether IPC is sufficient are repeated (and legitimate) in many pandemics and epidemics and should be anticipated.

The evidence base for IPC measures to mitigate the risks from COVID-19 continues to develop and evolve as understanding of the pathogen increases. In this context of evolving evidence, and particularly at the outset of the pandemic, some clinicians or groups of clinicians advocated for particular approaches based on an interpretation of latest evidence (for example, in relation to issues such as routes of transmission and the use of RPE). However, the evidence base has continually evolved and so ongoing care is required interpreting latest outputs.

It was important that UK COVID-19 IPC guidance remained consistent with WHO recommendations and that the UK-wide COVID-19 IPC guidance and principles had consistency of strategic approach across the 4 national health and care systems. Collaboration and co-operation between IPC policy and operational leads and external stakeholders, such as the Health and Safety Executive, ventilation engineers and clinical experts, added additional expertise (and independence) to the IPC COVID-19 guidance and thus contributed to increased certainty and standardisation of approach across the system. While there was cross-UK variation in terms of governance, all UK countries had a shared view that there needed to be clear communication, understanding of responsibilities, and ownership of IPC and health protection guidance and its implementation across IPC and health protection stakeholders.

In any pandemic, it is likely that the complexity and rapidity of asks falling on clinicians and healthcare settings means that interpreting IPC guidance at speed is difficult and that as a result IPC guidance is at risk of being inconsistently applied across different settings. Appropriate strategic and educational support was key, not only at a local level but also from regional and national IPC teams, both of which were strengthened in terms of resource during this period. Fit-testing for staff is also an important way to ensure that everyone is aware of relevant RPE requirements and has the appropriate PPE to protect them in different scenarios.

Importantly, the design of buildings and other infrastructure (in both clinical and non-clinical environments) also impacted trusts’ and clinicians’ ability to implement IPC guidance and to optimise mitigations such as bed spacing, using single or isolation rooms or ventilation during the pandemic. An ongoing collaborative approach between IPC, estates and facilities teams regarding new builds, ventilation and review of technical notes can help mitigate such issues.

The SARS-CoV-2 pandemic highlighted existing disparities between IPC practice and expertise in health and social care, and across different areas of healthcare. IPC measures were embedded in secondary healthcare and elements of primary care (such as dentistry) as part of core business before the pandemic. In other areas, the importance of IPC has become more evident over the course of the pandemic – for example, in mental health and learning disability services where implementing guidance can be particularly difficult. During the pandemic, links between the health and social care sectors to align IPC approaches have strengthened, and programmes of work have been established to share expertise, such as NHS provision of IPC training to all care homes in England under mutual aid arrangements. Such efforts are important legacies of the pandemic.

Robust, standardised, evidence-based IPC guidance along with consistent implementation has been vital to ensuring the safety of healthcare workers, patients and visitors across the health and care system throughout this pandemic. However, there is an ongoing need to balance the direct harms of infection against the unintended consequences and potential harms of control interventions. For example, the introduction of enhanced COVID-19 IPC practices and health protection measures may impact service capacity which in turn risks increasing morbidity through reduced services.

Enhanced IPC practices may also have implications for the wider support needs of patients, such as restricting visiting for advocates supporting people with a learning disability or birthing partners, though again this needs to be balanced with the potentially serious (and, in the early stages of a pandemic, often unknown) impacts of infection in these same groups.

Such decisions required a balanced consideration of multiple factors, such as case rates and the possible direct and indirect health harms of the pandemic, and continual reassessment as new variants emerged, natural immunity increased and therapeutics and vaccines weakened the link between infection and severe outcomes.

Reflections and advice for a future CMO or GCSA

Many of the lessons we learned in clinical management and operational design were likely to be specific to COVID-19 but some key learnings were more general.

Point 1

Improvements in care reflect the extraordinary efforts of medical, nursing and allied staff.

Their repeated determination to go well beyond their normal practice over prolonged periods, learn and disseminate best clinical practice and redesign operational systems for the benefit of patients was remarkable.

Point 2

The rapid flow of international experience was absolutely essential, whether through formal routes or through informal networks.

UK clinicians and scientists benefited from the experience of colleagues from China, Singapore, South Korea, Japan, India, the USA, many European nations and South Africa, among others.

There is a difficult balance between learning from others who are most affected, and taking up their time when they are most under pressure, but the experience was that sharing of information worked well. Publications and group briefings (for example, via WHO) should wherever possible be the mechanism for doing this.

Point 3

Observational studies like CO-CIN and SIREN provided essential insights into severe and mild-moderate disease.

Trials remain the gold standard, especially for therapeutics, but evidence emerges rapidly from clinicians learning by doing, and from systematic observational studies.

Point 4

Management of PPE and best infection control advice in healthcare settings was very difficult.

The balance between what would be ideal and what is possible was one tension which is likely to be repeated in future, as is the balance between keeping up with the global evidence base and keeping routines stable. This issue probably provided the greatest point of tension between individual medical practitioners and those trying to provide a standardised approach to IPC, not made easier by the practical difficulties of getting PPE in the face of unprecedented global demand.

We anticipate this difficulty will be repeated in any epidemic and pandemic of any size, noting that IPC and PPE needs are not universal between different infections. Certain items such as gloves and aprons are very likely to be needed. These are operational issues that need to be considered by the operational leads.

Point 5

Training of staff for redeployment was essential, and considering issues of indemnity and registration was central to having staff able to practise safely and legally.

Engaging early with the GMC was essential. The use of recently retired staff has many great advantages, but in the face of a disease whose greatest risks are to older people, some of those volunteering had to consider risks carefully.

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