Mapping the impacts of climate change on prehospital emergency medical services: protocol for a scoping review

Abstract

Introduction

Climate change is intensifying extreme weather events and altering environmental conditions in ways that increasingly strain health systems. Prehospital emergency medical services (EMS), as the frontline interface between communities and acute care, are uniquely vulnerable to these pressures. Rising call volumes, infrastructure disruption, occupational heat and smoke exposure and service delays have been reported, yet the evidence remains fragmented across disciplines and regions. This scoping review aims to systematically map the global literature on climate-related hazards and their impacts on EMS operations, workforce health, patient outcomes and system adaptation.

Methods and analysis

This scoping review follows Joanna Briggs Institute methodology and will be reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses extensions for Scoping Reviews (PRISMA-ScR). Searches will be conducted in PubMed/MEDLINE, Web of Science, Scopus, CINAHL and Embase together with grey literature sources for English-language studies published from 2000 onwards. Using the Population–Concept–Context framework, studies on climate-related hazards affecting prehospital EMS operations, workforce health, patient outcomes or system adaptation will be included. Non-EMS studies, studies unrelated to climate-related hazards and non-primary reports will be excluded. Two reviewers will independently screen and chart the data. Findings will be summarised descriptively and thematically and presented in an evidence map.

Ethics and dissemination

As this study uses publicly available data, ethical approval is not required. Findings will be disseminated through peer-reviewed publication, conference presentations and policy-oriented outputs targeting EMS leaders and public health stakeholders.

STRENGTHS AND LIMITATIONS OF THIS STUDY.

• Adherence to established Joanna Briggs Institute scoping review methodology and Preferred Reporting Items for Systematic Reviews and Meta-Analyses extensions for Scoping Reviews reporting guidelines ensures rigour and transparency.

• A comprehensive, peer-reviewed search strategy maximises the likelihood of identifying all relevant literature.

• The inclusion of grey literature and diverse study designs captures the breadth of emerging evidence.

• Restriction to English-language publications may introduce bias.

• Consistent with scoping review methodology, no formal quality appraisal of included studies will be undertaken.

Introduction

Emergency medical services (EMS) represent the first operational link in the chain of survival for time-sensitive conditions, including out-of-hospital cardiac arrest, major trauma and acute stroke.^1–3 Timely response and effective prehospital care are strongly associated with better patient outcomes; for example, in cardiac arrest, each minute of delay in defibrillation is estimated to reduce survival by 7%–10%.⁴ Ensuring that EMS systems are responsive, well-resourced and operationally reliable is, therefore, an essential component of health system performance.⁵

Climate change is increasingly recognised as a major threat to global health.^6–8 Extreme weather events such as heatwaves, floods, storms and wildfires are occurring more frequently and with greater intensity in many regions, while gradual environmental changes, including rising temperatures and deteriorating air quality, continue to alter patterns of acute illness and injury.^{6 7} These shifts can increase demand for emergency care and place additional pressure on health system infrastructure and personnel.^7–9

EMS operations are particularly vulnerable to these pressures. Unlike hospital-based services, EMS depends on functional transport networks, reliable communication systems, workforce mobility and safe working conditions. Evidence suggests that higher ambient temperatures are associated with increased ambulance call volumes and longer response times.^{10 11} Exposure to wildfire smoke and air pollution can exacerbate respiratory and cardiovascular conditions requiring urgent care.¹² Extreme weather events, including floods and storms, may disrupt road access, damage infrastructure and delay responses.¹³ In addition, occupational heat stress and environmental exposure pose direct risks to EMS personnel, potentially affecting workforce health, safety and retention.¹⁴

Despite these challenges, research examining the impact of climate-related hazards on EMS remains fragmented across disciplines, including disaster medicine, environmental epidemiology, occupational health and health services research.^{10 15 16} Studies differ in design, geographic focus and outcome measures, and there has been no systematic effort to map the overall scope and characteristics of this evidence. As health systems increasingly aim to build resilience to climate change,¹⁷ a comprehensive understanding of how environmental hazards affect prehospital services is needed.

A scoping review is, therefore, warranted to collate the existing literature, describe the nature and distribution of evidence and identify gaps in knowledge. Such an approach will provide a foundation for future research and support the integration of EMS considerations into broader strategies for climate-resilient health system planning.

Study rationale and objectives

Climate change is reshaping the operational environment in which EMS systems function. However, existing evidence regarding its effects on EMS performance, workforce health, patient outcomes and adaptive capacity is fragmented and unevenly distributed across regions and hazard types. Without a consolidated evidence base, strategic planning and policy development for climate-resilient prehospital care remain constrained. This scoping review will systematically map the global literature, characterise the nature and extent of available evidence and identify critical knowledge gaps to guide future research and system-level adaptation.

Methods and analysis

This protocol has been developed in accordance with the Joanna Briggs Institute (JBI) methodology for scoping reviews and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extensions for Protocols (PRISMA-P) and Scoping Reviews (PRISMA-ScR).^{18 19} The final review will be reported using the PRISMA-ScR checklist.

Step 1: identifying the research question

Consistent with the iterative nature of scoping reviews, the research question was refined through preliminary literature scanning and multiple rounds of discussion among the multidisciplinary authorship team. The overarching research question is: what evidence exists concerning the impacts of climate change and climate-sensitive environmental hazards on prehospital EMS operations, workforce health and patient outcomes?

The question is operationalised through four subsidiary questions:

1. What is the extent, distribution and methodological composition of the available literature?

2. Which climate-related hazards have been studied, and what specific impacts on EMS operations, personnel and patients have been reported?

3. What adaptive strategies or policies have been proposed, trailed or implemented to address these impacts?

4. Where are the principal gaps and methodological weaknesses in the current evidence base?

Step 2: eligibility criteria

The Population, Concept, Context (PCC) framework, recommended by JBI for scoping reviews, guides the eligibility criteria.²⁰

Population

We will include any literature pertaining to organised, formal prehospital EMS. This includes public, private and volunteer-based EMS agencies; ground and air ambulance services; dispatch centres; and all categories of prehospital personnel (paramedics, emergency medical technicians, emergency medical dispatchers, community first responders acting within an organised scheme). Studies that exclusively address hospital-based emergency care, primary care or non-organised bystander assistance will be excluded.

Concept

The core concept is the influence of climate change or climate-sensitive environmental hazards on EMS. Eligible hazards include:

• Acute extreme weather events: heatwaves, wildfires, floods, storms (including hurricanes, cyclones, typhoons), cold spells and severe winter weather.

• Slow-onset environmental changes attributable to climate change: progressive increases in ambient temperature, worsening ambient air quality (eg, particulate matter, ozone, aeroallergens) and shifts in the geographic or seasonal distribution of vector-borne diseases.

  • We will include studies that explicitly investigate an association, correlation or causal relationship between these hazards and an EMS-related outcome as well as qualitative or descriptive accounts of experiences, challenges and adaptations.

Context

No geographic or setting restrictions will be applied. Studies conducted in urban, suburban, rural, remote or wilderness settings are all eligible. Studies of EMS in military, humanitarian or conflict settings will be excluded unless they clearly pertain to climate-related hazards in civilian populations.

Types of evidence sources

We will adopt an inclusive approach. Eligible source types comprise:

• Peer-reviewed primary research: quantitative, qualitative and mixed-methods studies.

• Peer-reviewed secondary research: systematic reviews that address relevant questions will be retained for reference mining but will not be the primary focus of data extraction.

• Grey literature: technical reports, policy documents, government agency publications, doctoral dissertations and conference proceedings, provided they contain substantive, non-opinion-based data or analysis.

• Exclusions: editorials, commentaries, letters, narrative reviews without systematic methods and news articles.

Temporal and language limits

The contemporary scientific consensus on anthropogenic climate change solidified around the turn of the millennium; consequently, we will restrict inclusion to documents published from 1 January 2000 onward. Only documents published in the English language will be considered.

Step 3: information sources and search strategy

This study will adhere to PRISMA guidelines and a search strategy will be developed to identify relevant publications. Electronic searches will be carried out in Google Scholar, Web of Science Core Collection, PubMed and Scopus. Before beginning the database search, we will consult the Medical Subject Headings (MeSH) database to identify appropriate keywords and related terms associated with ‘climate change’ and ‘prehospital emergency medical services’. We will also incorporate additional relevant terms such as ‘global warming’, ‘extreme weather events’, ‘heatwaves’, ‘natural disasters’, ‘emergency medical services (EMS)’, ‘prehospital care’, ‘out-of-hospital care’, ‘ambulance services’ and ‘emergency medical technicians’ to ensure a comprehensive search strategy. Databases will be searched using the following syntax presented in table 1.

Table 1. Search strategy.

Database	Formula	Result
PubMed	((“Climate Change”(Mesh])OR “Global Warming”(Mesh])OR “Weather”(Mesh])OR “Air Pollution”(Mesh])OR “Natural Disasters”(Mesh])OR “Temperature”(Mesh])OR climate change(tiab])OR global warming(tiab])OR climate variability(tiab])OR extreme weather(tiab])OR extreme event*(tiab])OR heatwave*(tiab])OR extreme heat(tiab])OR heat stress(tiab])OR high temperature*(tiab])OR cold spell*(tiab])OR flood*(tiab])OR storm*(tiab])OR hurricane*(tiab])OR cyclone*(tiab])OR typhoon*(tiab])OR wildfire*(tiab])OR forest fire*(tiab])OR drought*(tiab])OR natural disaster*(tiab])OR air pollution(tiab])OR particulate matter(tiab])OR PM2.5(tiab])OR ozone(tiab])OR wildfire smoke(tiab])OR ambient temperature(tiab)) AND (“Emergency Medical Services”(Mesh])OR “Ambulances”(Mesh])OR “Emergency Medical Technicians”(Mesh])OR “Emergency Medical Dispatch”(Mesh])OR emergency medical services(tiab])OR EMS(tiab])OR prehospital care(tiab])OR pre-hospital care(tiab])OR out-of-hospital care(tiab])OR ambulance*(tiab])OR paramedic*(tiab])OR emergency medical technician*(tiab])OR EMT(tiab])OR emergency medical dispatcher*(tiab])OR dispatch center*(tiab))) Filters: English; 2000–present.	N =?
Web of Science	TS= ((“climate change” OR “global warming” OR “climate variability” OR “climate hazard*” OR “climate-related” OR “extreme weather” OR “extreme event*” OR heatwave* OR “extreme heat” OR “heat stress” OR “high temperature*” OR “ambient temperature” OR “cold spell*” OR “severe winter weather” OR flood* OR storm* OR hurricane* OR cyclone* OR typhoon* OR wildfire* OR “forest fire*” OR drought* OR “natural disaster*” OR “air pollution” OR “particulate matter” OR PM2.5 OR ozone OR “wildfire smoke” OR “environmental exposure*") AND (“emergency medical services” OR EMS OR “prehospital care” OR “pre-hospital care” OR “out-of-hospital care” OR “ambulance service*” OR ambulance* OR paramedic* OR “emergency medical technician*” OR EMT OR “emergency medical dispatcher*” OR “dispatch center*” OR “out-of-hospital emergency care”))	N =?
Scopus	(TITLE-ABS-KEY (“climate change” OR “global warming” OR “climate variability” OR “extreme weather” OR “extreme event*” OR heatwave* OR “extreme heat” OR “heat stress” OR “high temperature*” OR “cold spell*” OR flood* OR storm* OR hurricane* OR cyclone* OR typhoon* OR wildfire* OR “forest fire*” OR drought* OR “natural disaster*” OR “air pollution” OR “particulate matter” OR PM2.5 OR ozone OR “wildfire smoke” OR “ambient temperature”)) AND (TITLE-ABS-KEY(“emergency medical services” OR EMS OR “prehospital care” OR “pre-hospital care” OR “out-of-hospital care” OR ambulance* OR paramedic* OR “emergency medical technician*” OR EMT OR “emergency medical dispatcher*” OR “dispatch center*"))	N =?

Step 4: study selection process

All records identified through database searches and grey literature sources will be imported into EndNote (Clarivate Analytics) for removal of duplicate entries. After deduplication, the remaining records will be transferred to Rayyan,²¹ a web-based application developed to facilitate collaborative screening in systematic and scoping reviews. Study selection will be conducted independently by two reviewers in two sequential phases. Title and abstract screening: each reviewer will evaluate titles and abstracts according to the predefined PCC eligibility criteria. Any record considered potentially eligible by at least one reviewer will proceed to full-text assessment. Full-text review: the complete texts of all potentially relevant studies will be retrieved and independently assessed by the same two reviewers. Reasons for exclusion at this stage will be documented and reported. Disagreements at any stage will be resolved through discussion; if consensus cannot be reached, a third senior reviewer will adjudicate. Prior to commencing formal screening, a calibration exercise will be performed on a random sample of 50 records to ensure consistent application of the eligibility criteria.

The overall study selection process will be summarised in a PRISMA-ScR flow diagram (figure 1), which will illustrate the number of records identified, screened, excluded (with reasons) and included in the final review.

Figure 1. PRISMA Flow Diagram for Scoping Review Process (PRISMA-ScR).

Step 5: data charting

Data will be extracted using a standardised data extraction form developed a priori by the research team. The form will be piloted on a subset of 5 to 10 included studies and refined iteratively to ensure all relevant information is captured. Two reviewers will independently extract data from each included source. Discrepancies will be resolved through consensus or, if necessary, adjudication by a third reviewer. Where information is missing or unclear, corresponding authors will be contacted by email.

Step 6: data analysis and synthesis

Consistent with scoping review methodology, the analysis will be primarily descriptive and will not include meta-analysis or formal quality appraisal. We will employ two complementary synthesis approaches:

1. Descriptive numerical summary: we will use frequencies, percentages and, where appropriate, measures of central tendency to summarise: publication trends over time, geographic distribution of research activity, distribution of study designs and source types, frequency with which specific climate hazards and EMS outcome domains have been investigated.

2. Thematic content analysis: we will conduct qualitative thematic analysis of the textual data extracted from included sources.²² This will involve iterative reading, line-by-line coding of findings relevant to each subquestion, and organisation of codes into broader descriptive themes. Themes will be refined through discussion within the research team. NVivo software (or equivalent) will be used to facilitate coding and theme management.

3. Evidence mapping: the central visual output will be an evidence map, presented as a bubble plot or matrix.²³ The horizontal axis will represent categories of climate hazard (eg, extreme heat, wildfire, flood, air pollution); the vertical axis will represent categories of EMS outcome (eg, operational performance, workforce health, patient outcomes, adaptation strategies). Each cell will contain a bubble whose size reflects the volume of evidence (number of studies) and whose colour or shading denotes the predominant study design(s). This map will provide an immediate, intuitive overview of where evidence is concentrated and, equally importantly, where it is absent.

Patient and public involvement

None.

Ethics and dissemination

This scoping review will use data exclusively from previously published, publicly accessible documents. No individual-level data will be collected, and no direct interaction with human subjects will occur. Therefore, ethical approval is not required.

Findings will be disseminated through peer-reviewed publications, conference presentations and policy-oriented outputs targeting EMS leaders and public health stakeholders. We are committed to ensuring that the findings of this review reach both academic and non-academic audiences and support evidence-informed decision-making in emergency care systems.

Discussion

Climate change is increasingly recognised as a major threat to health systems, with documented implications for service delivery, workforce capacity and emergency preparedness.^24–26 Despite this growing recognition, the specific impacts of climate-related hazards on prehospital EMS have not been systematically mapped. Given the operational dependence of EMS on transportation networks, environmental working conditions and rapid response capability, understanding these vulnerabilities is essential for health system resilience planning.

This scoping review will provide the first comprehensive synthesis of the global literature examining climate-related hazards and their effects on EMS operations, workforce health, patient outcomes and adaptation strategies. By applying established JBI methodology²⁰ and presenting findings through descriptive synthesis and evidence mapping,²³ the review will clarify the scope, distribution and methodological characteristics of existing research while identifying critical knowledge gaps.

The review has several strengths, including a comprehensive multidatabase search strategy, inclusion of grey literature and independent dual screening. However, limitations include restriction to English-language publications and the absence of formal quality appraisal, consistent with scoping review methodology.²⁰ It will include only English-language studies from 2000 onwards, which may exclude relevant evidence. The expected heterogeneity of studies may limit comparability of findings, and as a scoping review, it will map the evidence rather than assess study quality or infer causality.

By systematically mapping this emerging field, the review aims to inform future research priorities and support the integration of prehospital services into broader climate-resilient health system planning frameworks.