Beyond prognostication: ambulance personnel’s lived experiences of cardiac arrest decision-making

Emergency reflex action drill for traumatic cardiac arrest in a simulated pre-hospital setting; a one-group pre-post intervention study

BACKGROUND

Emergency Reflex Action Drills (ERADs) are meant to decrease stress-associated cognitive demand in high urgency situations. The aim of this study was to develop and test an ERAD for witnessed traumatic cardiac arrest (TCA), an event in which potentially reversible causes need to be systematically addressed and treated in a short period of time. We hypothesize that this ERAD (the TCA-Drill) helps ground Emergency Medical Services (EMS) nurses in overcoming performance decline during this specific high-pressure situation.

METHODS

This was a prospective, experimental one-group pre-post intervention study. Ground EMS nurses participated in a session of four simulated scenarios, with an in-between educational session to teach the TCA-Drill. Scenarios were video recorded, after which adherence and time differences were analyzed. Self-confidence on clinical practice was measured before and after the scenarios.

RESULTS

Twelve ground EMS nurses participated in this study. Overall median time to address reversible causes of TCA decreased significantly using the TCA-Drill (132 vs. 110 s; p = 0.030) compared with the conventional ALS strategy. More specifically, participants adhering to the TCA-Drill showed a significantly lower time needed for hemorrhage control (58 vs. 37 s; p = 0.012). Eight of 12 (67 %) ground EMS nurses performed the ERAD without protocol deviations. Reported self-confidence significantly increased on 11 of the 13 surveyed items.

CONCLUSIONS

The use of an ERAD for TCA (the TCA-Drill) significantly reduces the time to address reversible causes for TCA without delaying chest compressions in a simulated environment and can be easily taught to ground EMS nurses and increases self-confidence.

IMPLICATIONS FOR CLINICAL PRACTICE

The use of an ERAD for TCA (the TCA-Drill can significantly reduce the time to address reversible causes for TCA without delaying chest compression. This drill can be easily taught to ground EMS nurses and increases their self-confidence in addressing TCA-patients.

Views and perceptions of advanced life support practitioners on initiating, withholding and terminating resuscitation in out-of-hospital cardiac arrest in the Emergency Medical Services of South Africa

Introduction

This study aimed to explore the views and perceptions of Advanced Life Support (ALS) practitioners in two South African provinces on initiating, withholding, and terminating resuscitation in OHCA.

Methodology

Semi-structured one-on-one interviews were conducted with operational ALS practitioners working within the prehospital setting in the Western Cape and Free State provinces. Recorded interviews were transcribed and subjected to inductive-dominant, manifest content analysis. After familiarisation with the data, meaning units were condensed, codes were applied and collated into categories that were then assessed, reviewed, and refined repeatedly.

Results

A total of 18 ALS providers were interviewed. Five main categories were developed from the data analysis: 1) assessment of prognosis, 2) internal factors affecting decision-making, 3) external factors affecting decision-making, 4) system challenges, and 5) ideas for improvement. Factors influencing the assessment of prognosis were history, clinical presentation, and response to resuscitation. Internal factors affecting decision-making were driven by emotion and contemplation. External factors affecting decision-making included family, safety, and disposition. System challenges relating to bystander response and resources were identified. Ideas for improvement in training and support were brought forward.

Conclusion

Many factors influence OHCA decision-making in the Western Cape and Free State provinces, and numerous system challenges have been identified. The findings of this study can be used as a frame of reference for prehospital emergency care personnel and contribute to the development of context-specific guidelines.

Mediators of the Association Between Socioeconomic Status and Survival After Out-of-Hospital Cardiac Arrest: A Systematic Review

Low socioeconomic status (SES) is associated with poor outcomes after out-of-hospital cardiac arrest (OHCA). Patient characteristics, care processes, and other contextual factors may mediate the association between SES and survival after OHCA. Interventions that target these mediating factors may reduce disparities in OHCA outcomes across the socioeconomic spectrum. This systematic review identified and quantified mediators of the SES-survival after OHCA association. Electronic databases (MEDLINE, Embase, PubMed, Web of Science) and grey literature sources were searched from inception to July or August 2023. Observational studies of OHCA patients that conducted mediation analyses to evaluate potential mediators of the association between SES (defined by income, education, occupation, or a composite index) and survival outcomes were included. A total of 10 studies were included in this review. Income (n = 9), education (n = 4), occupation (n = 1), and composite indices (n = 1) were used to define SES. The proportion of OHCA cases that had bystander involvement, presented with an initial shockable rhythm, and survived to hospital discharge or 30 days increased with higher SES. Common mediators of the SES-survival association that were evaluated included initial rhythm (n = 6), emergency medical services response time (n = 5), and bystander cardiopulmonary resuscitation (n = 4). Initial rhythm was the most important mediator of this association, with a median percent excess risk explained of 37.4% (range 28.6%-40.0%; n = 5; 1 study reported no mediation) and mediation proportion of 41.8% (n = 1). To mitigate socioeconomic disparities in outcomes after OHCA, interventions should target potentially modifiable mediators, such as initial rhythm, which may involve improving bystander awareness of OHCA and the need for prompt resuscitation.

Advanced paramedics' restraint decision-making when managing acute behavioural disturbance (ABD) in the UK pre-hospital ambulance setting: A qualitative investigation

Acute behavioural disturbance (ABD), sometimes called 'excited delirium', is a medical emergency. In the UK, some patients presenting with ABD are managed by advanced paramedics (APs), however little is known about how APs make restraint decisions. The aim of this research is to explore the decisions made by APs when managing restraint in the context of ABD, in the UK pre-hospital ambulance setting. Seven semi-structured interviews were undertaken with APs. All participants were experienced APs with post-registration, post-graduate advanced practice education and qualifications. The resulting data were analysed using reflexive thematic analysis, informed by critical realism. We identified four interconnected themes from the interview data. Firstly, managing complexity and ambiguity in relation to identifying ABD patients and determining appropriate treatment plans. Secondly, feeling vulnerable to professional consequences from patients deteriorating whilst in the care of APs. Thirdly, negotiating with other professionals who have different roles and priorities. Finally, establishing primacy of care in relation to incidents which involve police officers and other professionals. A key influence was the need to characterise incidents as medical, as an enabler to establishing clinical leadership and decision-making control. APs focused on de-escalation techniques and sought to reduce physical restraint, intervening with pharmacological interventions if necessary to achieve this. The social relationships and interactions with patients and other professionals at the scene were key to success. Decisions are a source of anxiety, with fears of professional detriment accompanying poor patient outcomes. Our results indicate that APs would benefit from education and development specifically in relation to making ABD decisions, acknowledging the context of inter-professional relationships and the potential for competing and conflicting priorities. A focus on joint, high-fidelity training with the police may be a helpful intervention.

Factors that influence paramedic decision-making about resuscitation for treatment of out of hospital cardiac arrest: Results of a discrete choice experiment in National Health Service ambulance trusts in England and Wales

Background

During out of hospital cardiac arrest (OHCA) paramedics must make decisions to commence, continue, terminate or withhold resuscitation. These decisions are known to be complex, subject to variability and often dependent on provider preference. This study aimed to understand paramedic decision-making regarding the commencement of resuscitation using a discrete choice experiment.

Methods

A discrete choice experiment between October-December 2022 surveying paramedics from ten National Health Service ambulance trusts in England and Wales. Respondents were presented with fourteen vignettes, each comprising thirteen attributes, and asked to decide if they would provide resuscitation or not.

Results

Eight hundred and sixty-four paramedics completed the survey (61.8% male, median age 36 years (IQR 17.1)) and half had < 5 years clinical experience (n = 443 (51.2%). Respondents expressed a general preference to offer resuscitation (p = <0.01). All attributes except patient gender were statistically significant and important regarding an offer of resuscitation. Cut-offs where an offer of resuscitation was less likely were patient age of 73 years (p=>0.05), mild dementia (p = >0.05) and moderate frailty (p = <0.01). Paramedic characteristics of female gender, longest (>10 years) and shortest (<5 years) period qualified, lower academic qualification, lower skill level and attending fewer OHCA's were more likely to result in an offer of resuscitation.

Conclusion

During OHCA paramedics use objective and non-objective factors to make pragmatic decisions regarding an offer of resuscitation. Future research should focus on how best to support paramedics to make decisions during OHCA, how variability in decision-making impacts patient outcomes and how this relates to patient and public expectations.

Fears and Concerns of Bystanders to Help People Injured in Traffic Accidents: A Qualitative Descriptive Study

In most traffic accidents, bystanders arrive at the scene before the rescuers. If they provide the right help, they can play an important and effective role in reducing the number of deaths and complications caused by these accidents. However, in many cases, fears and concerns prevent bystanders from providing assistance. This study aims to investigate and understand the fears and concerns of bystanders when they decide to help in traffic accidents. In 2022, this study was carried out in Iran using a qualitative content analysis approach. The data was collected through semistructured interviews. Participants were 15 males and females who had experience providing assistance in traffic accidents. Interviews, after digital recording, were transcribed verbatim. A purposeful and theoretical sampling method was performed. Data analysis and the determination of codes, categories, and subcategories were done using qualitative analysis software. O'Brien's qualitative research reporting standard was used. The results of the study include a category of fears and concerns and five subcategories. The subcategories include fear and concern caused by lack of information, fear of legal troubles, stress caused by previous experience, fear and anxiety caused by anticipation, and anxiety of unknown origin. The results of this study showed that some of the fears and concerns of the bystanders were related to a lack of information about providing assistance. By increasing bystanders' information about assistance, such as first aid training, fear and anxiety caused by a lack of information can be reduced. Another part of the fear and concern of bystanders is due to legal issues. Passing and implementing laws that protect bystanders can help reduce this fear and concern. Bystanders should be trained to provide assistance according to the rules of assistance so that they do not get into legal problems. A part of the bystander's fear and concern stems from their previous experiences providing assistance in traffic accidents. These experiences can also affect the fear and anxiety caused by anticipation. It is necessary to conduct more studies on the role of bystanders' experiences in creating fear and anxiety in them, as well as their effect on anticipatory fear.

The impact of COVID-19 on emergency medical service-led out-of-hospital cardiac arrest resuscitation: a qualitative study

Background

Following the emergence of COVID-19, there have been local and national changes in the way emergency medical service (EMS) staff respond to and treat patients in out-of-hospital cardiac arrest (OHCA). The views of EMS staff on the impact of COVID-19 and management of OHCA have not previously been explored. This study aimed to explore the views of staff, with a specific focus on communication during resuscitation, resuscitation procedures and the perception of risk.

Methods

A qualitative phenomenological enquiry was conducted. A purposive sample of n = 20 participants of various clinical grades was selected from NHS EMS providers in the United Kingdom. Data were collected using semi-structured interviews, transcribed verbatim and inductive thematic analysis was applied.

Results

Three main themes emerged which varied according to clinical grade, location and guidelines.Decision making: Staff generally felt supported to make best-interest termination of resuscitation decisions. Staff made informed decisions to compromise on recommended levels of personal protective equipment (PPE), since it felt impractical in the pre-hospital context, to improve communication or to reduce delays to care.Service pressures: Availability of operational staff and in-hospital capacity were reduced. Staff felt pressure and disconnect from the continuous updates to clinical guidelines which resulted in organisational change fatigue.Moral injury: The emotional impacts of prolonged and frequent exposure to failed resuscitation attempts and patient death caused many staff to take time away from work to recover.

Conclusion

This qualitative study is the first known to explore staff views on the impacts of COVID-19 on OHCA resuscitation, which found positive outcomes but also negative impacts important to inform EMS systems. Staff felt that COVID-19 created delays to the delivery of resuscitation, which were multi-faceted. Staff developed new ways of working to overcome the barriers of impractical PPE. There was little impact on resuscitation procedures. Moving forwards, EMS should consider how to limit organisational change and better support the ongoing emotional impacts on staff.

Factors influencing prehospital physicians' decisions to initiate advanced resuscitation for asystolic out-of-hospital cardiac arrest patients

BACKGROUND

The decision to initiate or continue advanced life support (ALS) in out-of-hospital cardiac arrest (OHCA) could be difficult due to the lack of information and contextual elements, especially in non-shockable rhythms. This study aims to explore factors associated with clinicians' decision to initiate or continue ALS and the conditions associated with higher variability in asystolic patients.

METHODS

This retrospective observational study enrolled 2653 asystolic patients on whom either ALS was attempted or not by the emergency medical services (EMS) physician. A multivariable logistic regression analysis was performed to find the factors associated with the decision to access ALS. A subgroup analysis was performed on patients with a predicted probability of ALS between 35% and 65%. The single physicians' behaviour was compared to that predicted by the model taking into account the entire agency.

RESULTS

Age, location of event, bystander CPR and EMS-witnessed event were independent factors influencing physicians' choices about ALS. Non-medical OHCA, younger patients, less experienced physicians, presence of breath activity at the emergency call and a longer time for ALS arrival were more frequent among cases with an expected higher variability in behaviours with ALS. Significant variability was detected between physicians.

CONCLUSIONS

Significant inter-physician variability in access to ALS could be present within the same EMS, especially among less experienced physicians, non-medical OHCA and in presence of signs of life during emergency call. This arbitrariness has been observed and should be properly addressed by EMS team members as it raises ethical issues regarding the disparity in treatment.

External validation and insights about the calibration of the return of spontaneous circulation after cardiac arrest (RACA) score

Background

The return of spontaneous circulation (ROSC) after cardiac arrest (RACA) score was developed as a tool to predict ROSC probability (pROSC) based on easily available information and it could be useful to compare the performances of different EMS agencies or the effects of eventual interventions.

We performed an external validation of the RACA score in a cohort of out of hospital cardiac arrest (OHCA) patients managed by the EMS of the metropolitan city of Bologna, Italy.

Methods

We analyzed data from 2,310 OHCA events prospectively collected between January 2009 and June 2021. Discrimination was assessed with the area under the ROC curve (AUROC), while the calibration belts were used for the comparison of observed versus expected ROSC rates. The AUROCs from our cohort and other validation cohorts were compared using a studentized range test.

Results

The AUROC for the study population was 0.691, comparable to that described by previous validation studies. Despite an acceptable overall calibration, we found a poor calibration for asystole and low pROSC ranges in PEA and shockable rhythms. The model showed a good calibration for patients aged over 80, while no differences in performance were found when evaluating events before and after the implementation of 2015 ERC guidelines.

Conclusions

Despite AUROC values being similar in different validation studies for RACA score, we suggest separating the different rhythms when assessing ROSC probability with the RACA score, especially for asystole.

Non-medical factors in prehospital resuscitation decision-making: a mixed-methods systematic review

Aim

This systematic review explored how non-medical factors influence the prehospital resuscitation providers’ decisions whether or not to resuscitate adult patients with cardiac arrest.

Methods

We conducted a mixed-methods systematic review with a narrative synthesis and searched for original quantitative, qualitative, and mixed-methods studies on non-medical factors influencing resuscitation of out-of-hospital cardiac arrest. Mixed-method reviews combine qualitative, quantitative, and mixed-method studies to answer complex multidisciplinary questions. Our inclusion criteria were peer-reviewed empirical-based studies concerning decision-making in prehospital resuscitation of adults > 18 years combined with non-medical factors. We excluded commentaries, case reports, editorials, and systematic reviews. After screening and full-text review, we undertook a sequential exploratory synthesis of the included studies, where qualitative data were synthesised first followed by a synthesis of the quantitative findings.

Results

We screened 15,693 studies, reviewed 163 full-text studies, and included 27 papers (12 qualitative, two mixed-method, and 13 quantitative papers). We identified five main themes and 13 subthemes related to decision-making in prehospital resuscitation. Especially the patient’s characteristics and the ethical aspects were included in decisions concerning resuscitation. The wishes and emotions of bystanders further influenced the decision-making. The prehospital resuscitation providers’ characteristics, experiences, emotions, values, and team interactions affected decision-making, as did external factors such as the emergency medical service system and the work environment, the legislation, and the cardiac arrest setting. Lastly, prehospital resuscitation providers’ had to navigate conflicts between jurisdiction and guidelines, and conflicting values and interests.

Conclusions

Our findings underline the complexity in prehospital resuscitation decision-making and highlight the need for further research on non-medical factors in out-of-hospital cardiac arrest.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-022-01004-6.

Documentation of ethically relevant information in out-of-hospital resuscitation is rare: a Danish nationwide observational study of 16,495 out-of-hospital cardiac arrests

Background

Decision-making in out-of-hospital cardiac arrest should ideally include clinical and ethical factors. Little is known about the extent of ethical considerations and their influence on prehospital resuscitation. We aimed to determine the transparency in medical records regarding decision-making in prehospital resuscitation with a specific focus on ethically relevant information and consideration in resuscitation providers’ documentation.

Methods

This was a Danish nationwide retrospective observational study of out-of-hospital cardiac arrests from 2016 through 2018. After an initial screening using broadly defined inclusion criteria, two experienced philosophers performed a qualitative content analysis of the included medical records according to a preliminary codebook. We identified ethically relevant content in free-text fields and categorised the information according to Beauchamp and Childress’ four basic bioethical principles: autonomy, non-maleficence, beneficence, and justice.

Results

Of 16,495 medical records, we identified 759 (4.6%) with potentially relevant information; 710 records (4.3%) contained ethically relevant information, whereas 49 did not. In general, the documentation was vague and unclear. We identified four kinds of ethically relevant information: patients’ wishes and perspectives on life; relatives’ wishes and perspectives on patients’ life; healthcare professionals’ opinions and perspectives on resuscitation; and do-not-resuscitate orders. We identified some “best practice” examples that included all perspectives of decision-making.

Conclusions

There is sparse and unclear evidence on ethically relevant information in the medical records documenting resuscitation after out-of-hospital cardiac arrests. However, the “best practice” examples show that providing sufficient documentation of decision-making is, in fact, feasible. To ensure transparency surrounding prehospital decisions in cardiac arrests, we believe that it is necessary to ensure more systematic documentation of decision-making in prehospital resuscitation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12910-021-00654-y.

Prehospital Resuscitation Decision Making: A model of ambulance personnel experiences, preparation and support

OBJECTIVE

This paper presents the first Naturalistic Decision Making model of prehospital resuscitation decision-making, which has clear implications for education, practice and support.

METHODS

A mixed-methods exploratory sequential research design consisting of interviews with ambulance personnel (study 1), focus groups with ambulance educators, managers and peer supporters (study 2), and an online survey of graduating paramedic students (study 3). This paper reports the model developed from integrated findings, across all three studies. All research was undertaken in New Zealand and underpinned by a critical realist worldview.

RESULTS

The Prehospital Resuscitation Decision Making model identifies key processes, challenges and facilitators before, during and after ambulance personnel attend a cardiac arrest event. It is the only descriptive model of resuscitation decision making which acknowledges the decision-maker, non-prognostic factors and the importance of adequate preparation and support.

CONCLUSIONS

This research project is the first to comprehensively explore and model ambulance personnel perspectives on decisions to start, continue or stop resuscitation. The decision-making process is complex and difficult to simply formularise. Education and supports must assist ambulance personnel in navigating this complexity. Where resuscitation is withheld or terminated, ambulance personnel need to feel confident that they can effectively provide after-death care.

Death and dying in prehospital care: what are the experiences and issues for prehospital practitioners, families and bystanders? A scoping review

OBJECTIVE

To identify the factors that shape and characterise experiences of prehospital practitioners (PHPs), families and bystanders in the context of death and dying outside of the hospital environment where PHPs respond.

DESIGN

A scoping review using Arksey and O'Malley's five-stage framework. Papers were analysed using thematic analysis.

DATA SOURCES

MEDLINE; Embase; CINAHL; Scopus; Social Sciences Citation Index (Web of Science), ProQuest Dissertations & Theses A&I (Proquest), Health Technology Assessment database; PsycINFO; Grey Literature Report and PapersFirst were searched from January 2000 to May 2019.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Qualitative and mixed methods studies reporting the experiences of PHPs, families and bystanders of death and dying in prehospital settings as a result of natural causes, trauma, suicide and homicide, >18 years of age, in Europe, USA, Canada, Australia and New Zealand.

RESULTS

Searches identified 15 352 papers of which 51 met the inclusion criteria. The review found substantial evidence of PHP experiences, except call handlers, and papers reporting family and bystander experiences were limited. PHP work was varied and complex, while confident in clinical work, they felt less equipped to deal with the emotion work, especially with an increasing role in palliative and end-of-life care. Families and bystanders reported generally positive experiences but their support needs were rarely explored.

CONCLUSIONS

To the best of our knowledge this is the first review that explores the experiences of PHPs, families and bystanders. An important outcome is identifying current gaps in knowledge where further empirical research is needed. The paucity of evidence suggested by this review on call handlers, families and bystanders presents opportunities to investigate their experiences in greater depth. Further research to address the current knowledge gaps will be important to inform future policy and practice.

Non-technical skills in paramedicine: A scoping review

This scoping review aims to identify which non-technical skills have been empirically identified in the literature, to create the first list of empirically identified non-technical skills for paramedics and allied health personnel. A five-stage scoping literature was undertaken in March 2020. The search retrieved a total of 4756 citations. A total of 93 studies met the inclusion criteria and were analyzed for data charting. A total of 26 non-technical skills were identified in the literature. The top five non-technical skills included decision-making (33%, n = 31), communication (24%, n = 23), empathy (17%, n = 16), leadership (12%, n = 12), and ethics (10%, n = 10). Furthermore, only five studies investigated the assessment or measurement of non-technical skills. This scoping review identified 26 non-technical skills that had been investigated in the paramedic literature to create the first list of empirically based desirable non-technical skills for a paramedic. Subsequently, research can then begin to focus on identifying the link that these have to paramedic practice and patient safety.

Decision making in prehospital traumatic cardiac arrest; A qualitative study

BACKGROUND

Despite improving survival of patients in prehospital traumatic cardiac arrest (TCA), initiation and/or discontinuation of resuscitation of TCA patients remains a subject of debate among prehospital emergency medical service providers. The aim of this study was to identify factors that influence decision making by prehospital emergency medical service providers during resuscitation of patients with TCA.

METHODS

Twenty-five semi-structured interviews were conducted with experienced ambulance nurses, HEMS nurses and HEMS physicians individually, followed by a focus group discussion. Participants had to be currently active in prehospital medicine in the Netherlands. Interviews were encoded for analysis using ATLAS.ti. Using qualitative analysis, different themes around decision making in TCA were identified.

RESULTS

Eight themes were identified as being important factors for decision making during prehospital TCA. These themes were: (1) factual information (e.g., electrocardiography rhythm or trauma mechanism); (2) fear of providing futile care or major impairment if return of spontaneous circulation was obtained; (3) potential organ donation; (4) patient age; (5) suspicion of attempted suicide; (6) presence of bystanders or family; (7) opinions of other team members; and (8) training and education. Several ambulance nurses reported they do not feel adequately supported by the current official national ambulance guidelines on TCA, nor did they feel sufficiently trained to perform pre-hospital interventions such as endotracheal intubation or needle thoracocentesis on these patients.

CONCLUSION

Eight themes were identified as being important for decision making during prehospital TCA. While guidelines based on prognostic factors are important, it should be recognized that decision making in TCA is impacted by more than factual information alone. This should be reflected in educational programs and future guidelines.

Unlocking intuition and expertise: using interpretative phenomenological analysis to explore clinical decision making

BACKGROUND

Clinical decision making is a complex, but important, research area. Decision-making theories have evolved to recognise that, although heuristics and biases can lead to error, expert clinician decision makers can also use intuition to good effect. More research is needed to understand how nurses and other clinicians make sense of complexity and uncertainty.

AIM

This paper discusses the utility of interpretative phenomenological analysis to elucidate clinical decision making, expertise and intuition.

METHODS

A narrative review of published interpretative phenomenological analysis studies exploring clinical decision-making, and discussion of an exemplar study.

RESULTS

A limited number of interpretative phenomenological analysis studies have been published in this area. By seeking out descriptions of real-world decision making, interpretative phenomenological analysis research provides ecologically valid insights into what it is like to make time-critical, high-stakes decisions with limited information.

CONCLUSION

Contributing to the study of complex clinical decision making in combination with other research approaches, interpretative phenomenological analysis research has significant unrealised potential to inform education, assessment and support interventions and the development of clinical guidelines. Future applications could enhance understanding of multi-disciplinary decision-making and the development of expertise and intuition, over time.

Field termination-of-resuscitation rule for refractory out-of-hospital cardiac arrests in Japan

BACKGROUND

Guidelines for cardiopulmonary resuscitation (CPR) recommend using the universal termination-of-resuscitation (TOR) rule to identify out-of-hospital cardiac arrest (OHCA) patients eligible for field termination of resuscitation, thus avoiding medically futile transportation to the hospital. However, in Japan, emergency medical services (EMS) personnel are forbidden from terminating CPR in the field and transport almost all patients with OHCA to hospitals. We aimed to develop and validate a novel TOR rule to identify patients eligible for field termination of CPR.

METHODS

We analyzed 540,478 patients with OHCA from 2011 to 2015 using a Japanese registry. Main outcome measures were specificity and positive predictive value (PPV) of the newly developed TOR rule in predicting 1-month mortality after OHCA.

RESULTS

Recursive partitioning analysis in the development group (n=434,208) showed that EMS personnel could consider TOR if patients with OHCA met all of the following five criteria: (1) initial asystole, (2) arrest unwitnessed by a bystander, (3) age ≥81 years, (4) no bystander-administered CPR or automated external defibrillator use before EMS arrival, and (5) no return of spontaneous circulation after EMS-initiated CPR for 14min. For patients meeting these criteria, specificity and PPV for predicting 1-month mortality were 99.2% [95% confidence interval (CI), 99.0-99.3%] and 99.7% (95% CI, 99.6-99.7%), respectively, for the development group and were 99.5% (95% CI, 99.3-99.7%) and 99.8% (95% CI, 99.7-99.9%), respectively, for the validation group. Implementation of this novel rule would reduce patient transports to hospitals by 10.6% in the development group and 10.4% in the validation group.

CONCLUSIONS

Having both high specificity and PPV of >99% for predicting 1-month mortality, our developed TOR rule may be applied in the field for Japanese patients with OHCA who meet all five criteria. Prospective validation studies and establishment of prehospital EMS protocol are required before implementing this rule.