Venous blood point-of-care testing (POCT) for paramedics in urgent and emergency care: protocol for a single-site feasibility study (POCTPara).

The COVID-19 pandemic placed the UK healthcare system under unprecedented pressure, and recovery will require whole-system investment in innovative, flexible and pragmatic solutions. Positioned at the heart of the healthcare system, ambulance services have been tasked with addressing avoidable hospital conveyance and reducing unnecessary emergency department and hospital attendances through the delivery of care closer to home. Having begun to implement models of care intended to increase 'see and treat' opportunities through greater numbers of senior clinical decision makers, emphasis has now been placed upon the use of remote clinical diagnostic tools and near-patient or point-of-care testing (POCT) to aid clinical decision making. In terms of POCT of blood samples obtained from patients in the pre-hospital setting, there is a paucity of evidence beyond its utility for measuring lactate and troponin in acute presentations such as sepsis, trauma and myocardial infarction, although potential exists for the analysis of a much wider panel of analytes beyond these isolated biomarkers. In addition, there is a relative dearth of evidence in respect of the practicalities of using POCT analysers in the pre-hospital setting. This single-site feasibility study aims to understand whether it is practical to use POCT for the analysis of patients' blood samples in the urgent and emergency care pre-hospital setting, through descriptive data of POCT application and through qualitative focus group interviews of advanced practitioners (specialist paramedics) to inform the feasibility and design of a larger study. The primary outcome measure is focus group data measuring the experiences and perceived self-reported impact by specialist paramedics. Secondary outcome measures are number and type of cartridges used, number of successful and unsuccessful attempts in using the POCT analyser, length of time on scene, specialist paramedic recruitment and retention, number of patients who receive POCT, descriptive data of safe conveyance, patient demographics and presentations where POCT is applied and data quality. The study results will inform the design of a main trial if indicated.

Stakeholder perspectives of piloting pre-hospital COVID-19 lateral flow testing and direct admissions pathway: exploring why well-received ideas have low uptake.

Introduction: In January 2021, Yorkshire Ambulance Service and Hull University Teaching Hospitals implemented a pilot COVID-19 lateral flow testing (LFT) and direct admissions pathway to assess the feasibility of using pre-hospital LFTs to bypass the emergency department. Due to lower than anticipated uptake of the pilot among paramedics, we undertook a process evaluation to assess reasons for low uptake and perceived potential benefits and risks associated with the pilot. Methods: We undertook semi-structured telephone interviews with 12 paramedics and hospital staff. We aimed to interview paramedics who had taken part in the pilot, those who had received the project information but not taken part and ward staff receiving patients from the pilot. We transcribed interviews verbatim and analysed data using thematic analysis. Results: Participation in the pilot appeared to be positively influenced by high personal capacity for undertaking research (being 'research-keen') and negatively influenced by 'COVID-19 exhaustion', electronic information overload and lack of time for training. Barriers to use of the pathway related to 'poor timing' of the pilot, restrictive patient eligibility and inclusion criteria. The rapid rollout meant that paramedics had limited knowledge or awareness of the pilot, and pilot participants reported poor understanding of the pilot criteria or the rationale for the criteria. Participants who were involved in the pilot were overwhelmingly positive about the intervention, which they perceived as having limited risks and high potential benefits to the health service, patients and themselves, and supported future roll-out. Conclusions: Ambulance clinician involvement in rapid research pilots may be improved by using multiple recruitment methods (electronic and other), providing protected time for training and increased direct support for paramedics with lower personal capacity for research. Improved communication (including face-to-face approaches) may help understanding of eligibility criteria and increase appropriate recruitment.

The experiences and perceptions of wellbeing provision among English ambulance services staff: a multi-method qualitative study.

BACKGROUND: NHS ambulance service staff are at risk of poor physical and mental wellbeing because of the likelihood of encountering stressful and traumatic incidents. While reducing sickness absence and improving wellbeing support to ambulance staff is a key NHS priority, few studies have empirically documented a national picture to inform policy and service re-design. The study aimed to understand how ambulance service trusts in England deal with staff health and wellbeing, as well as how the staff perceive and use wellbeing services. METHODS: To achieve our aim, we undertook semi-structured telephone interviews with health and wellbeing leads and patient-facing ambulance staff, as well as undertaking documentary analysis of ambulance trust policies on wellbeing. The study was conducted both before and during the UK first COVID-19 pandemic wave. The University of Lincoln ethics committee and the Health Research Authority (HRA) granted ethical approval. Overall, we analysed 57 staff wellbeing policy documents across all Trusts. Additionally, we interviewed a Health and Wellbeing Lead in eight Trusts as well as 25 ambulance and control room staff across three Trusts. RESULTS: The study highlighted clear variations between organisational and individual actions to support wellbeing across Trust policies. Wellbeing leads acknowledged real 'tensions' between individual and organisational responsibility for wellbeing. Behaviour changes around diet and exercise were perceived to have a positive effect on the overall mental health of their workforce. Wellbeing leads generally agreed that mental health was given primacy over other wellbeing initiatives. Variable experiences of health and wellbeing support were partly contingent on the levels of management support, impacted by organisational culture and service delivery challenges for staff. CONCLUSION: Ambulance service work can impact upon physical and mental health, which necessitates effective support for staff mental health and wellbeing. Increasing the knowledge of line managers around the availability of services could improve engagement.

‘Every day was a learning curve’: the experience of implementing COVID-19 triage protocols in UK ambulance services – a qualitative study

BackgroundTRIM is an evaluation of the models used to triage and manage emergency ambulance service care for patients with suspected Covid-19 during the first wave of the pandemic in 2020. We aimed to understand experiences and concerns of clinical and managerial staff about implementation of triage protocols in call centre and on-scene.MethodsResearch paramedics in four study sites across England interviewed purposively selected stakeholders from ambulance services (call handlers, clinical advisors in call centres, clinicians providing emergency response, managers) and ED clinical staff from one hospital per site. Interviews (n=23) were conducted remotely using MS Teams, recorded, and transcribed in full. Analysis generated themes from the implicit and explicit ideas within participants’ accounts, following the six stages of analysis described by Braun and Clarke, conducted by a group of researchers and PPI partners working together.ResultsWe identified the following themes:Constantly changing guidelines – at some points, updates several times a dayThe ambulance service as part of the wider healthcare system - changes in other parts of the healthcare system left ambulance services as the default optionPeaks and troughs of demand - demand fluctuated greatly over time, with workload varying across the ambulance service, including an increased role for clinical advisorsA stretched system - resources to respond to patient demand were stretched thinner by staff sickness and isolation, longer job times, and increased handover delays at EDEmotional load of responding to the pandemic - particularly for call centre staffDoing the best they can in the face of uncertainty - in the face of a rapidly evolving situation unlike any which ambulance services had faced beforeDiscussionImplementing triage protocols in response to the Covid-19 pandemic was a complex and process which had to be actively managed by a range of front line staff, dealing with external pressures and a heavy emotional load.

Perceptions and experiences of wellbeing provision for NHS ambulance staff: a qualitative interview study of wellbeing leads and frontline staff

BackgroundThe wellbeing of ambulance staff is critical to their safety and safe care delivery. This study examined the perceptions of English NHS ambulance Trust health and wellbeing leads, and the experiences of UK ambulance staff of workplace wellbeing culture and provision.MethodsSemi-structured telephone interviews were undertaken with staff wellbeing leads for eight NHS ambulance trusts in England and with ambulance staff from three NHS ambulance trusts in England, selected to represent services with high, medium or low relative sickness absence rates. Interviews were subsequently transcribed, coded and analysed using Framework Analysis (FA).ResultsWe interviewed eight wellbeing leads and 25 frontline ambulance staff from April-November 2020. Decisions around what was included in or omitted from wellbeing policies sometimes led to conflict between wellbeing leads and their superiors. Ambulance work was perceived as inherently unhealthy because of work stress and the risk of encountering traumatic incidents. Well-being leads understood the adverse impacts of work on mental health for some staff. Ambulance staff wanted empathy, understanding and practical support from managers, but the reality did not always match these needs, because of variability in provision and experiences of health and wellbeing services, poor behaviours or attitudes from line managers, and a stigmatising rather than open organisational culture. COVID-19 not only impacted significantly on staff health and wellbeing, but also challenged how ambulance trusts support them.ConclusionsThe importance of an open organisational culture and the variable availability and experiences of interventions to support staff to stay well at work means that improvements are needed in both to ensure positive staff mental health and wellbeing. Early interventions, improved training for line managers to support staff at work, bespoke wellbeing services and an open culture are key to delivering effective support to ambulance staff, especially in the light of the COVID-19 pandemic.

Stakeholder perspectives of piloting pre-hospital COVID-19 lateral flow test and direct admissions pathway: exploring why well received ideas have low uptake

BackgroundIn January 2021 Yorkshire Ambulance Service and Hull University Teaching Hospitals implemented a pilot COVID-19 lateral flow testing (LFT) and direct admissions pathway to assess the feasibility of using pre-hospital LFTs to bypass the Emergency Department. Due to lower than anticipated uptake of the pilot amongst paramedics, we undertook a service evaluation to assess reasons for low uptake and perceived potential benefits and risks associated with the pilot.MethodsWe undertook semi-structured telephone interviews with 12 paramedics and hospital staff. We aimed to interview paramedics who had taken part in the pilot, those who had received the project information but not taken part and ward staff receiving patients from the pilot. We transcribed interviews verbatim and analysed data using thematic analysis according to the principles of Braun & Clarke (Ref).ResultsParticipants who were involved in the pilot were overwhelmingly positive about the intervention, which they perceived as having limited risks and high potential benefits to the health service, patients and themselves and supported future roll-out. Participation in the pilot appeared to be positively influenced by high personal capacity for undertaking research (being ‘research-keen) and negatively influenced by ‘COVID-19 exhaustion’, electronic information overload and lack of time for training. Barriers to use of the pathway related to ‘poor timing’ of the pilot, restrictive patient eligibility and inclusion criteria. The rapid rollout meant that paramedics had limited knowledge or awareness of the pilot, and pilot participants reported poor understanding of the pilot criteria or the rationale for the criteria.ConclusionsAmbulance clinician involvement in rapid research pilots may be improved by using multiple recruitment methods (electronic and other), providing protected time for training and increased direct support for paramedics with lower personal capacity for research. Improved communication (including face-to-face approaches) may help understanding of eligibility criteria and increase appropriate recruitment.

Accuracy of emergency medical service telephone triage of need for an ambulance response in suspected COVID-19: an observational cohort study.

OBJECTIVE: To assess accuracy of emergency medical service (EMS) telephone triage in identifying patients who need an EMS response and identify factors which affect triage accuracy. DESIGN: Observational cohort study. SETTING: Emergency telephone triage provided by Yorkshire Ambulance Service (YAS) National Health Service (NHS) Trust. PARTICIPANTS: 12 653 adults who contacted EMS telephone triage services provided by YAS between 2 April 2020 and 29 June 2020 assessed by COVID-19 telephone triage pathways were included. OUTCOME: Accuracy of call handler decision to dispatch an ambulance was assessed in terms of death or need for organ support at 30 days from first contact with the telephone triage service. RESULTS: Callers contacting EMS dispatch services had an 11.1% (1405/12 653) risk of death or needing organ support. In total, 2000/12 653 (16%) of callers did not receive an emergency response and they had a 70/2000 (3.5%) risk of death or organ support. Ambulances were dispatched to 4230 callers (33.4%) who were not conveyed to hospital and did not deteriorate. Multivariable modelling found variables of older age (1 year increase, OR: 1.05, 95% CI: 1.04 to 1.05) and presence of pre-existing respiratory disease (OR: 1.35, 95% CI: 1.13 to 1.60) to be predictors of false positive triage. CONCLUSION: Telephone triage can reduce ambulance responses but, with low specificity. A small but significant proportion of patients who do not receive an initial emergency response deteriorated. Research to improve accuracy of EMS telephone triage is needed and, due to limitations of routinely collected data, this is likely to require prospective data collection.

Accuracy of telephone triage for predicting adverse outcomes in suspected COVID-19: an observational cohort study.

OBJECTIVE: To assess accuracy of telephone triage in identifying need for emergency care among those with suspected COVID-19 infection and identify factors which affect triage accuracy. DESIGN: Observational cohort study. SETTING: Community telephone triage provided in the UK by Yorkshire Ambulance Service NHS Trust (YAS). PARTICIPANTS: 40 261 adults who contacted National Health Service (NHS) 111 telephone triage services provided by YAS between 18 March 2020 and 29 June 2020 with symptoms indicating COVID-19 infection were linked to Office for National Statistics death registrations and healthcare data collected by NHS Digital. OUTCOME: Accuracy of triage disposition was assessed in terms of death or need for organ support up to 30 days from first contact. RESULTS: Callers had a 3% (1200/40 261) risk of serious adverse outcomes (death or organ support). Telephone triage recommended self-care or non-urgent assessment for 60% (24 335/40 261), with a 1.3% (310/24 335) risk of adverse outcomes. Telephone triage had 74.2% sensitivity (95% CI: 71.6 to 76.6%) and 61.5% specificity (95% CI: 61% to 62%) for the primary outcome. Multivariable analysis suggested respiratory comorbidities may be overappreciated, and diabetes underappreciated as predictors of deterioration. Repeat contact with triage service appears to be an important under-recognised predictor of deterioration with 2 contacts (OR 1.77, 95% CI: 1.14 to 2.75) and 3 or more contacts (OR 4.02, 95% CI: 1.68 to 9.65) associated with false negative triage. CONCLUSION: Patients advised to self-care or receive non-urgent clinical assessment had a small but non-negligible risk of serious clinical deterioration. Repeat contact with telephone services needs recognition as an important predictor of subsequent adverse outcomes.

Accuracy of telephone triage for predicting adverse outcomes in suspected COVID-19: an observational cohort study

798 Figure 1STROBE flow diagram of study population selection[Figure omitted. See PDF] 798 Table 1Performance of binary NHS 111 triage (ambulance or urgent assessment 4 hours or less) for composite outcome (death or organ support)Adverse outcome up to 30 days (3%, 2.8-3.2%) N=40, 261 Adverse Outcome No Adverse Outcome Ambulance/urgent assessment 890 15, 035 Sensitivity 74.2% (71.6- 76.6%) Positive Predictive Value 5.6% (5.2 - 6%) Self-care/non-urgent assessment 310 24, 025 Specificity 61.5% (61% - 62%) Negative Predictive Value 98.7% (98.6 - 98.9%) Results/Conclusions3% of the 40,261 callers experienced an adverse outcome. Self-care/non-urgent assessment was recommended for 60%, with a small but non-negligible (1.3%) risk of subsequent deterioration. Triage achieved 74.2% sensitivity (95% CI: 71.6 to 76.6%) and 61.5% specificity (61% to 62%) for the primary outcome. Multivariable analysis suggested some co-morbidities (e.g. respiratory disease) may be over-estimated, and others (e.g. diabetes) underestimated, as predictors of deterioration. Repeat contact with services appears to be an important under recognised predictor of adverse outcomes with 2 contacts (OR 1.77 95% CI: 1.14 to 2.75) and 3+ contacts (OR 4.02 95% CI: 1.68 to 9.65) associated with clinical deterioration when not provided with an ambulance/urgent clinical assessment.

Prognostic accuracy of triage tools for adults with suspected COVID-19 in a prehospital setting: an observational cohort study.

BACKGROUND: Tools proposed to triage patient acuity in COVID-19 infection have only been validated in hospital populations. We estimated the accuracy of five risk-stratification tools recommended to predict severe illness and compared accuracy to existing clinical decision making in a prehospital setting. METHODS: An observational cohort study using linked ambulance service data for patients attended by Emergency Medical Service (EMS) crews in the Yorkshire and Humber region of England between 26 March 2020 and 25 June 2020 was conducted to assess performance of the Pandemic Respiratory Infection Emergency System Triage (PRIEST) tool, National Early Warning Score (NEWS2), WHO algorithm, CRB-65 and Pandemic Medical Early Warning Score (PMEWS) in patients with suspected COVID-19 infection. The primary outcome was death or need for organ support. RESULTS: Of the 7549 patients in our cohort, 17.6% (95% CI 16.8% to 18.5%) experienced the primary outcome. The NEWS2 (National Early Warning Score, version 2), PMEWS, PRIEST tool and WHO algorithm identified patients at risk of adverse outcomes with a high sensitivity (>0.95) and specificity ranging from 0.3 (NEWS2) to 0.41 (PRIEST tool). The high sensitivity of NEWS2 and PMEWS was achieved by using lower thresholds than previously recommended. On index assessment, 65% of patients were transported to hospital and EMS decision to transfer patients achieved a sensitivity of 0.84 (95% CI 0.83 to 0.85) and specificity of 0.39 (95% CI 0.39 to 0.40). CONCLUSION: Use of NEWS2, PMEWS, PRIEST tool and WHO algorithm could improve sensitivity of EMS triage of patients with suspected COVID-19 infection. Use of the PRIEST tool would improve sensitivity of triage without increasing the number of patients conveyed to hospital.

The acceptability and safety of video triage for ambulance service patients and clinicians during the COVID-19 pandemic.

INTRODUCTION: In response to anticipated challenges with urgent and emergency healthcare delivery during the early part of the COVID-19 pandemic, Yorkshire Ambulance Service NHS Trust introduced video technology to supplement remote triage and 'hear and treat' consultations as a pilot project in the EOC. We conducted a service evaluation with the aim of investigating patient and staff acceptability of video triage, and the safety of the decision-making process. METHODS: This service evaluation utilised a mixture of routine and bespoke data collection. We sent postal surveys to patients who were recipients of a video triage, and clinicians who were involved in the video triage pilot logged calls they attempted and undertook. RESULTS: Between 27 March and 25 August 2020, clinicians documented 1073 triage calls. A successful video triage call was achieved in 641 (59.7%) cases. Clinical staff reported that video triage improved clinical assessment and decision making compared to telephone alone, and found the technology accessible for patients. Patients who received a video triage call and responded to the survey (40/201, 19.9%) were also satisfied with the technology and with the care they received. Callers receiving video triage that ended with a disposition of 'hear and treat' had a lower rate of re-contacting the service within 24 hours compared to callers that received clinical hub telephone triage alone (16/212, 7.5% vs. 2508/14349, 17.5% respectively). CONCLUSION: In this single NHS Ambulance Trust evaluation, the use of video triage for low-acuity calls appeared to be safe, with low rates of re-contact and high levels of patient and clinician satisfaction compared to standard telephone triage. However, video triage is not always appropriate for or acceptable to patients and technical issues were not uncommon.

The acceptability and safety of video triage for ambulance service patients and clinicians during the covid-19 pandemic: a service evaluation

IntroductionIn response to anticipated challenges with urgent and emergency healthcare delivery during the early part of the COVID-19 pandemic, Yorkshire Ambulance Service NHS Trust (YAS) introduced video call technology to supplement remote triage and ‘hear and treat’ consultations as a pilot project in the Emergency Operations Centre (EOC). We aimed to investigate patient and staff acceptability of video triage, and the safety of the decision-making process.MethodsThis service evaluation utilised a mixture of routine 999 call and bespoke data collection from participating clinicians who logged calls they both attempted and undertook. We sent postal surveys to a group of patients who were recipients of a video triage.ResultsBetween 27th March 2020 and 25th August 2020 clinicians documented 1073 video triage calls. A successful video triage call was achieved in 641 (59.7%) of cases. Clinical staff reported that video triage improved clinical assessment and decision making compared to telephone alone, and found the technology accessible for patients. Patients who received a video triage call and responded to the survey (40/201, 19.9%) viewed the technology, the ambulance staff and the care planning favourably.Callers receiving video triage that ended with a disposition of ‘hear and treat’, had a lower rate of re-contacting the service within 24 hours compared to callers that received clinical support desk telephone triage alone (16/212, 7.5% vs 2508/14349, 17.5% respectively.)ConclusionIn this single NHS Ambulance Trust evaluation, the use of video triage for low acuity calls appeared to be safe, with low rates of recontact and high levels of patient and clinician satisfaction compared to standard telephone triage. However, video triage is not always appropriate or acceptable to patients and technical issues were not uncommon.

Patterns of use of ambulance senior support during the COVID-19 pandemic: a service evaluation

BackgroundIn early March 2020, a senior clinical support cell (SCSC) was established within Yorkshire Ambulance Service NHS Trust (YAS). The SCSC aimed to provide an additional layer of clinical leadership within the Emergency Operations Centre to support call centre and decision support for on-scene ambulance staff working in challenging circumstances. It was staffed by advanced practitioners, doctors and other senior paramedics with range of diverse skills from critical to urgent care. We aimed to understand the patterns of use of a SCSC for emergency 999 calls during the COVID-19 pandemic.MethodsRoutinely collected call data was retrospectively analysed to understand the patterns of use in the first three months of the service. The reason for the call, patient demographic and any regional differences were described. An anonymous survey was distributed to frontline ambulance crews to understand the reasons for contacting the SCSC, or not, and the outcomes of that contact for patient care.Results7296 patient care episodes received either a telephone triage by SCSC for 999 calls or 111 calls transferred for an emergency ambulance response (3160) or had telephone support provided to crews on scene (4136). Telephone triage accounted for 3160 calls where 642 cases (20.3%) resulted in a hear-and-treat outcome, and the findings suggest a low re-contact rate within 24 hours at 2.4%.The primary reasons for crews seeking support/advice from the SCSC were discharge advice or permission (37%);support for pathways in their area (25%);or for cases where patients refused care or conveyance (11%).ConclusionsSCSC was developed in response to the COVID-19 pandemic, and lessons can be learned to prepare for any future significant service challenges as a result of the rapid implementation of the SCSC and the clinical leadership required to support the pace of change and emerging clinical knowledge and practice.

The take home naloxone intervention multicentre emergency setting feasibility (TIME) trial: an early perspective from one UK ambulance service

BackgroundDrug poisoning deaths in England and Wales have increased by 52% since 2011 with over half involving opioids. Deaths are preventable if naloxone is administered in time. Take Home Naloxone (THN) kits have been distributed through drug services;however, uptake is low and effectiveness unproven. The TIME trial tests the feasibility of conducting a full randomised controlled trial of providing THN administration and basic life support training to high-risk opioid-users in emergency care settings.MethodsA multi-site feasibility trial commenced in June 2019 with two hospitals and their surrounding ambulance services (Bristol Royal Infirmary (BRI) with South Western Ambulance NHS Foundation Trust (SWASFT) and Hull Royal Infirmary with Yorkshire Ambulance Service) randomly allocated to intervention arms;and sites in Wrexham and Sheffield allocated as ‘usual care’ controls. SWASFT began recruiting in October 2019 with the aim of recruiting and training 50% (n=111) of paramedics working within the BRI’s catchment area, to supply THN to at least 100 eligible patients during a 12-month period.ResultsThe trial was suspended between 17.03.2020-06.08.2020 and extended to 01.03.2021 (COVID-19). Despite this, 121 SWASFT paramedics undertook TIME training. TIME trained paramedics attended 30% (n=57) of the n=190 opioid-related emergency calls requiring naloxone administration during the study period. A total of n=29 potentially eligible patients were identified before and n=28 after the COVID-19 suspension. Two patients were supplied with THN during each period. During the COVID-19 suspension, twenty-two potentially eligible patients were missed. The majority of eligible patients presented with a reduced consciousness level, preventing recruitment (73%;n=42/48). These patients were transported to hospital for further treatment (n=39) or died on scene following advanced life support (n=3).ConclusionsThe lowered consciousness levels of prehospital emergency ambulance patients who present with opioid poisoning, often prevent the delivery of training required to enable the supply of THN.

Call volume, triage outcomes, and protocols during the first wave of the COVID-19 pandemic in the United Kingdom: Results of a national survey.

OBJECTIVES: During the first wave of the COVID-19 pandemic in the United Kingdom (UK), to describe volume and pattern of calls to emergency ambulance services, proportion of calls where an ambulance was dispatched, proportion conveyed to hospital, and features of triage used. METHODS: Semistructured electronic survey of all UK ambulance services (n = 13) and a request for routine service data on weekly call volumes for 22 weeks (February 1-July 3, 2020). Questionnaires and data request were emailed to chief executives and research leads followed by email and telephone reminders. The routine data were analyzed using descriptive statistics, and questionnaire data using thematic analysis. RESULTS: Completed questionnaires were received from 12 services. Call volume varied widely between services, with a UK peak at week 7 at 13.1% above baseline (service range -0.5% to +31.4%). All services ended the study period with a lower call volume than at baseline (service range -3.7% to -25.5%). Suspected COVID-19 calls across the UK totaled 604,146 (13.5% of all calls), with wide variation between services (service range 3.7% to 25.7%), and in service peaks of 11.4% to 44.5%. Ambulances were dispatched to 478,638 (79.2%) of these calls (service range 59.0% to 100.0%), with 262,547 (43.5%) resulting in conveyance to hospital (service range 32.0% to 53.9%). Triage models varied between services and over time. Two primary call triage systems were in use across the UK. There were a large number of products and arrangements used for secondary triage, with services using paramedics, nurses, and doctors to support decision making in the call center and on scene. Frequent changes to triage processes took place. CONCLUSIONS: Call volumes were highly variable. Case mix and workload changed significantly as COVID-19 calls displaced other calls. Triage models and prehospital outcomes varied between services. We urgently need to understand safety and effectiveness of triage models to inform care during further waves and pandemics.