How Paramedics Experience the Decision to Continue or Terminate Out-of-Hospital Resuscitation: A Scoping Review Protocol

Out-of-hospital cardiac arrest (OHCA) is a common, acute life-threatening emergency: An average incidence of 56 cases per 100,000 inhabitants per year is reported for Europe (Gräsner et al., 2020); worldwide, the incidence ranges from 30 to 100 per 100,000 inhabitants per year depending on population and health system (Nishiyama et al., 2023).

However, a potentially life-saving therapy (cardio-pulmonary resuscitation (CPR)) is only possible in the first few minutes after the onset of circulatory arrest. Irreparable damage to the brain due to hypoxia occurs within minutes, leading to death within a short period of time (Sandroni et al., 2021).

In most of the world's developed countries, paramedic systems are established, in which mainly non-physician emergency medical personnel (EMP) care for emergency patients. Within these systems, patients are treated, and decisions are made based on, for example, the EMPs' level of training, standard operating procedures, or consultation with a physician. In contrast, in Germany, patients with OHCA are cared for jointly by a physician-led team of medical and non-medical emergency personnel — a rare feature in the international context.

During resuscitation, a re-evaluation of the previous therapy attempts, the patient's condition, and the general conditions of the OHCA is performed regularly (Mentzelopoulos et al., 2021; Soar et al., 2021). In many cases, a decision must be made during treatment if and for how long the resuscitation should be continued.

In many paramedic systems, paramedics have the authority to make decisions for or against the continuation of resuscitation following legal restrictions (Feder et al., 2006; Grudzen et al., 2009; Grudzen et al., 2010; Mengual et al., 2007; Morrison et al., 2007; Sabatino, 1999). The situation in Germany differs: Resuscitation must be started by EMP in case of doubt but may only be terminated by physicians. However, resuscitation does not have to be started if there are certain signs of death.

The tension between the obligation to help, that is: to perform CPR on the one hand, and on the other hand, the individual and, in many cases, the possibly conflicting will of the patient (e.g. recorded in a do not attempt resuscitation (DNAR) order), in which EMPs find themselves when performing CPR on terminally ill people, for example, has been described comprehensively (Guru et al., 1999; Nordby & Nøhr, 2012; Torabi et al., 2018; Wiese et al., 2011). In this context, it should be emphasised that instructions and strategies for end-of-life decisions in Germany are directed exclusively at physicians (Wiese et al., 2011; Wurmb & Brederlau, 2016).

Qualitative studies suggest that EMPs address this ethical dilemma by respecting the patient's wishes as much as possible while adhering to the applicable regulations and incorporating their values and professional identity (Bruun et al., 2022; Torabi et al., 2018). The decision-making process for or against the continuation of resuscitation represents - independent of medical factors - a complex process in a field of tension of mutually influencing factors (Brandling et al., 2017; Milling et al., 2022).

Paramedics consider the option of not attempting or discontinuing resuscitation to be of great importance for their professional empowerment (Counts et al., 2021; Grudzen et al., 2009; Mengual et al., 2007). Professional empowerment and agency in ethically challenging situations are of particular importance because feelings of powerlessness regarding treatment decisions, a demanding medical work environment, lack of authority and high levels of responsibility can be a source of moral distress (Hefferman & Heilig, 1999; Lentz et al., 2021; Morley et al., 2019).

Previous studies indicate that a lack of empowerment in resuscitation care may have severe psychological effects. For example, the study by Tanabe et al. (2022) shows high stress levels for more than 30% of Japanese paramedics after medico-legally enforced care of patients with DNAR orders (Tanabe et al., 2022). These findings are not surprising, as medical staff responds to moral distress with various emotions (Lentz et al., 2021). These include, for example, anger, loneliness, depression, guilt, anxiety, feelings of powerlessness, and emotional withdrawal (Huffman & Rittenmeyer, 2012). These reactions can lead to physical symptoms over time.

Continued exposure to moral distress or serious events can potentially manifest in moral distress or even moral injuries (Čartolovni et al., 2021; Murray, 2019). To escape the suffering triggered by moral injuries, sufferers frequently leave their jobs or commit suicide (Smith-MacDonald et al., 2021). This scoping review aims to map the available evidence on paramedics' experience of the decision to continue or terminate resuscitation in out-of-hospital cardiac arrests.

For the reasons mentioned above, a public health issue could arise from the emergency medical personnel's experience of decisions for or against the termination of resuscitation.

So far, the current knowledge on this topic has not been comprehensively examined. Thus, we conducted a preliminary search of PubMed via MEDLINE on 8 March 2023. We couldn't identify any recent or underway systematic reviews or scoping reviews on this topic.

To close this research gap, we approach the research question by first operationalising the search terms with the PCC framework presented in Table 1.

Table 1 : Population, Concept, and Context (PCC) framework for identification of main concepts.

A	B
PCC element	Definition
Population	Non-physician emergency medical personnel who work in emergency medical services after regulated training. This includes paramedics and emergency medical technicians or the related country-specific professions.
Concept	Experiencing decisions to continue or terminate out-of-hospital resuscitation. Decisions include those made independently or based on standing orders or protocols; after consulting a decision-maker; by attending physicians, or by the team leader.
Context	Out-of-hospital decision-making.

From the PCC framework, we derive the research question as follows:

How do non-physician emergency medical personnel experience the decision to continue or terminate out-of-hospital resuscitation in the field?

Design

Our study will be a scoping review according to the JBI methodology (Peters et al., 2020), described in detail below. This protocol follows the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) 2015 statement (Moher et al., 2015). It was registered in advance with the Open Science Framework (Ristau et al., 2023).

Scoping reviews intend, among other purposes, to map a specific research topic's key concepts and identify and analyse knowledge gaps (Arksey & O'Malley, 2005; Peters et al., 2020). Their methodological strength derives from their ability to illustrate the breadth of knowledge.

Methods

Peters et al. (2020) provide a 9-step approach for conducting scoping reviews (Figure 1). Stages 1 to 3 must be pre-determined and specified within this protocol.

Eligibility Criteria

The inclusion and exclusion criteria result from the PCC framework and can be found in Table 2. In our review, we will not restrict the study design and the type of sources to cover the phenomenon of interest as broadly and comprehensively as possible.

Table 2 : In- and exclusion criteria.

A	B	C
Domain	Inclusion criteria	Exclusion criteria
Population	Non-physician Emergency Medical Personnel (EMP) working in Emergency Medical Service (EMS) after regulated training	Physician EMP, EMP without corresponding qualification
Phenomenon of interest	Report on experiences regarding decisions to continue or terminate out-of-hospital resuscitation outside the hospital	n/a
Study design	No limitations
Type of source	All kinds of scientific and grey literature	n/a
Language	English, German	n/a
Timeframe	No limitations

Dissemination of Results

We expect to submit the results in manuscript form to a peer-reviewed journal by the end of 2023. The presentation will consider the PRISMA Extension for Scoping Reviews (PRISMA-ScR) (Tricco et al., 2018). Furthermore, the results will be presented at a congress.

Study Team

PR is the principal investigator. He is academically supervised by PD and SD, which are available for consultation in case of queries and methodological questions. JR is a linguist and contributes her expertise to the selection of search terms and the definition of search terms. AW and MZ will alternately conduct a second screen of the titles/abstracts. The person not involved in the screening will decide on inclusion or exclusion in case of discrepancies between the first and the second screener. JR, AW, or MZ will perform as the second reviewer in the data collection stage. All authors have expertise in evidence synthesis and knowledge of emergency medical services. Each person will contribute their expertise to the manuscript preparation.

Information Sources

We will search the following databases for evidence:

• PubMed via MEDLINE
• CINAHL
• Cochrane Library
• CAMbase
• CareLit
• CC Med
• Scopus
• PsycARTICLES
• PsycINFO
• Web of Science

In addition, the bibliographies of the references included during the process will be searched for other potential matches by performing forward and backward citation tracking.

Search Strategy

As a first step, the PubMed, CINAHL, and Cochrane Library databases will be searched. Titles, abstracts, and index terms of the sources retrieved will be analysed regarding possible search terms. Professional advice will be sought from a linguist.

Data Management

All citations will be stored in the online database Rayyan (Rayyan Systems, Inc.) for further processing.

The full texts to be screened afterwards will be requested via our libraries or interlibrary loan service. If this is not possible, we will contact the authors and ask them to provide the full texts. If this approach fails and access to the full text is impossible, the corresponding citation will not be considered for this study.

We will use Citavi (Swiss Academic Software) and Excel (Microsoft Corporation) in their current versions to evaluate and extract full texts.

Selection Process

One quality feature of systematic reviews is the screening or selection of evidence by several people independently of each other (Peters et al., 2020). For this purpose, the selection process will be conducted by three people, both in the title/abstract screening and in the full-text review.

First, 25 random titles/abstracts will be screened by all three people involved in the selection process using the eligibility criteria and definitions. Subsequently, the reviewers will discuss any discrepancies and will make modifications to the eligibility criteria and definitions as appropriate. If a definite decision cannot be made, the supervisors will be asked for a final decision. The review process will not start until the review team has reached a match of at least 75%.

Subsequently, two persons will screen all titles/abstracts independently. Then the results will be compiled. The third person will finally decide on inclusion or exclusion in case of disagreement between the first two. Chapter 2.12 study team describes in detail which person will take on which task at each stage.

Data Collection and Extraction Process

A spreadsheet will support the collection of data from the included full texts. Two reviewers will record the following items independently in Citavi and will then be merged into a common spreadsheet:

1. Author(s)
2. Year of publication
3. Origin/country of origin (where the source was published or conducted)
4. Aims/purpose
5. Population and sample size within the source of evidence
6. Methodology/methods
7. Context of the study/paper
8. Key findings that relate to the scoping review question

Data Items

Table 3 shows the preliminary search terms derived from the PCC framework.

Table 3 : Preliminary search terms derived from the PCC framework.

A	B
PCC element	Search term
Population	(paramedic OR EMS OR EMT OR "emergency medical technician" OR Notfallsanitäter OR Rettungssanitäter OR Rettungsassistent OR Rettungsfachpersonal)
Concept	(CPR OR resuscitation OR OHCA OR "cardiac arrest" OR Reanimation OR Wiederbelebung) AND (experience OR view OR perspective OR Erleben OR erfahren OR Erfahrung OR wahrnehmen OR Wahrnehmung) AND (decision OR decision-making OR termination OR ToR OR DNAR OR Entscheidungsfindung OR Entscheidung OR Abbruch)
Context	(out-of-hospital OR prehospital OR OHCA OR field OR außerklinisch OR präklinisch)

A preliminary search term for use in PubMed is derived as follows:

((population OR EMS OR EMT OR “emergency medical technician” OR Notfallsanitäter OR Rettungssanitäter OR Rettungsassistent OR Rettungsfachpersonal) AND ((CPR OR resuscitation OR OHCA OR “cardiac arrest” OR Reanimation OR Wiederbelebung) AND (experience OR view OR perspective OR Erleben OR erfahren OR Erfahrung OR wahrnehmen OR Wahrnehmung) AND (decision OR decision-making OR termination OR ToR OR DNAR OR Entscheidungsfindung OR Entscheidung OR Abbruch)) AND (out-of-hospital OR prehospital OR OHCA OR field OR außerklinisch OR präklinisch))

The search terms for the other databases will be adapted according to their logic and functionality.

Data Analysis

The results obtained during the data collection process will be marked in Citavi, extracted in an Excel spreadsheet, and synthesised along core concepts. We will also analyse whether the results indicate any differences regarding

1. the autonomy of paramedics' professional practice,
2. the duration of their training or the scope of professional training,
3. and the competencies of paramedics.

Subsequently, the core concepts and results will be summarised narratively and contrasted comparatively. If appropriate, these will be summarised graphically.

Data Synthesis and Presentation

A PRISMA flowchart following Page et al. (2021) will report on the different stages of the review process and on the references that will have been included and excluded in the review process. The included articles will be presented in a table. The following contents will be listed in this table: (1) author(s), (2) year of publication, (3) origin/country of origin, (4) aims/purpose, (5) population and sample, (6) methodology/methods, (7) context of the study/paper.

Subsequently, the core concepts and results will be summarised narratively and contrasted comparatively. If appropriate, these will be summarised graphically.

Within this protocol, we present our planned scoping review, which will summarise the present knowledge of paramedics' experiences regarding the decision to continue or terminate out-of-hospital resuscitation in the field.

A possible limitation of our approach is the restriction to chosen languages, whereby the largest part of the available literature will be covered with English. Furthermore, the search for German-language studies will also address the country-specific conditions described above.

By publishing a scoping review protocol in advance, we increase transparency in describing study methods and enhance the value of our future results. This also enables peer reviewers and other researchers to comment critically on the approach before its application. We will conduct our study as described here but ensure to consider any proposed methodological refinement regarding the objective and purpose of the review in an appropriate manner.

The dissemination of our findings on paramedics' experiences on the decision to continue or terminate out-of-hospital resuscitation in the field through a scientific journal and at a congress may help to increase awareness and empathy regarding possible moral distress or even moral injuries. In the future, this awareness could possibly be used to create prevention opportunities, for example.

Furthermore, identifying gaps in the existing knowledge may constitute a foundation for methodological ideas and theoretical approaches toward future research. Our group of authors is currently preparing a qualitative study on the experience of decisions for or against the continuation of resuscitation by paramedics working in Germany.

CPR - Cardio-Pulmonary Resuscitation

DNAR - Do Not Attempt Resuscitation

EMP - Emergency Medical Personnel

EMS - Emergency Medical System

EMT - Emergency Medical Technician

JBI - Joanna Briggs Institute

OHCA - Out-of-Hospital Cardiac Arrest

PCC - Population Concept Context

PRISMA - Preferred Reporting Items for Systematic Review and Meta-Analysis

PRISMA-P - Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols

PRISMA-ScR - PRISMA Extension for Scoping Reviews

ToR - Termination of Resuscitation

Authors' contribution

This project is part of the first author's master thesis in public health. PR conducted the study conception and design, drafted the manuscript, and revised content based on feedback. PD and SD supervised the study conception and design. PD, SD, JR, AW, and MZ provided critical revisions of drafts. All authors approved the final version of the manuscript. PR is responsible for the integrity of this work as a whole.

Competing Interests

The authors declare no conflicts of interest.

Funding

No funding or third-party money was spent on this project.

Ethical Approval

According to German law, an ethical clearing is not required, as this study is a literature work.

Registration

Open Science Framework (https://doi.org/10.17605/OSF.IO/74D3Z))

This Scoping Review Protocol was registered on 13 March 2023 with the OSF Registries (Ristau et al., 2023).

Patrick Ristau 0000-0001-9847-4199

Johanna Ristau 0000-0002-7722-3312

Andreas Wagenplast 0000-0002-5418-0831

Marcel Zill 0000-0003-4151-7842

Philipp Dahlmann 0000-0002-8648-3810

Stefan Dietsche 0009-0003-5982-8144

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