Out-of-hospital cardiac arrest in low-resource settings; [EIT 634] Scoping Review

Conflict of Interest Declaration

The ILCOR Continuous Evidence Evaluation process is guided by a rigorous ILCOR Conflict of Interest policy. The following Task Force members and other authors were recused from the discussion as they declared a conflict of interest: None.

The following Task Force members and other authors declared an intellectual conflict of interest and this was acknowledged and managed by the Task Force Chairs and Conflict of Interest committees: None.

Task Force Scoping Review Citation

Schnaubelt S, Monsieurs KG, Semeraro F, Schlieber J, Cheng A, Bigham B, Garg R, Bhanji F, Bray JE, Breckwoldt J, Duff JP, Gilfoyle E, Glerup Lauridsen KG, Hsieh MJ, Iwami T, Lockey AS, Ma M, Okamoto D, Pellegrino JL, Yeung J, Finn J, Greif R.- on behalf of the International Liaison Committee on Resuscitation Education, Implementation and Teams Task Force. Prehospital Resuscitation in Low Resource Settings. Scoping review and Task Force Insights [Internet] Brussels, Belgium: International Liaison Committee on Resuscitation (ILCOR) Education, Implementation and Teams Task Force, 2020 January 31. Available from: http://ilcor.org

Methodological Preamble and Link to Published Scoping Review

This scoping review of prehospital resuscitation in low-resources settings was conducted by two experts of the ILCOR EIT Task Force Scoping Review team. Evidence for adult and paediatric literature was sought and considered by the EIT Task Force. The EIT task force discussed the evidence and provided insights.

Scoping Review

We expect to submit this Scoping Review for Publication in May 2020.

PICOST

The PICOST (Population, Intervention, Comparator, Outcome, Study Design and Timeframe) was defined as follows:

• Population: Adults and children living in low-resource settings
• Intervention: Prehospital resuscitation
• Comparison: No Comparator
• Outcomes: Improved clinical outcomes
• Study Design: Randomised controlled trials (RCTs) and non-randomised studies (non-randomised controlled trials, interrupted time series, controlled before-and-after studies, cohort studies) are eligible for inclusion. Unpublished studies (e.g., conference abstracts, trial protocols) were excluded.
• Timeframe: All years and all languages were included as long as there was an English abstract.

After extraction of the evidence, the scope of the review was narrowed (see “Search strategies” and “Inclusion and Exclusion criteria”).

Search Strategies

The search strategy was performed by information specialist Amanda Wanner and peer-reviewed by a second IS (16/12/2019).

2536 abstracts were imported in Rayyan (rayyan.qcri.org) and screened independently by Sebastian Schnaubelt and Koen Monsieurs; conflicting decisions were resolved by agreement. 21 additional duplicates were deleted, and 94 articles were included for full-text retrieval.

Important comments:

• • After the data extraction phase and after having considered the scope of the studies found, the EIT Task Force decided to exclude studies on trauma, children and neonates. This reduced the complexity of the review, limiting it to adult cardiac arrest of non-traumatic origin. We also decided to exclude studies on extracorporeal membrane oxygenation because this intervention indicates the presence of a high-resource setting.
• • Also after the data extraction phase, with regards to the timeframe, we decided to exclude articles published before 01/01/2009, thereby limiting the results to the last decade (this included 71% of all screened abstracts). We did this because low and middle income countries develop over time, and conclusions based on older studies may therefore be no longer relevant today.
• • Also after the data extraction phase, we decided to group outcomes as “ROSC” and “longer-term” outcome because of the heterogeneity of the reported outcomes.

Inclusion and Exclusion Criteria

(adjusted after the data extraction phase)

To identify “low resource settings”, we applied the World Bank definition to classify countries in 4 categories by gross national income (GNI) per capita (https://datahelpdesk.worldbank.org/knowledgebase/articles/906519-world-bank-country-and-lending-groups):

• low-income economies ($1,025 or less),
• lower-middle income economies ($1,026 to $3,995),
• upper-middle income economies ($3,996 to $12,375) and
• high-income economies ($12,376 or more).

All data except those coming from high-income economies were rated as low-resource for this scoping review. For every study, we applied the World Bank category of the country in the year the study was published.

Inclusion criteria:

• Data coming from a low-resource setting (= not in high-income category)
• An abstract in English is available during the initial database search
• Human studies
• Prehospital cardiopulmonary resuscitation (= for out of hospital cardiac arrest)
• Adult resuscitation
• Abstract published between 01/01/2009 and 16/12/2019 (the date of the search)

Exclusion criteria

• Studies evaluating scoring systems
• Studies with self-assessment as the only outcome
• Manikin studies
• Simulation studies
• Studies not reporting any clinical outcome
• Reviews
• Abstracts without full article when not enough information could be retrieved from the abstract
• Economic evaluations
• Studies on sepsis
• Studies on prevention of cardiac arrest
• Wilderness medicine
• Combat medicine
• Disaster situations
• Unpublished studies (e.g. conference abstracts, posters, trial protocols)
• Studies not reporting the number of resuscitation attempts (denominator)
• Studies not reporting at least ROSC as an outcome
• Studies reporting on trauma or on very specific other populations (e.g. mechanical CPR or intoxication or drowning)

Remark: the fact that we excluded specific populations does not mean that they may not be relevant to low resource settings. These specific populations may be the subject of future reviews.

Data tables

Table 3: Data extraction table. Population: adults with non-traumatic prehospital cardiac arrest. Outcomes expressed as percentages of the whole population studied. Footnote 1: Resource situation in the year of publication of the study, expressed as GNI/capita as published by the World Bank (datahelpdesk.worldbank.org/knowledgebase/articles/906519-world-bank-country-and-lending-groups).

Task Force Insights

1. Why this topic was reviewed

In 2015 ILCOR published a Consensus on Science and Treatment Recommendation (CoSTR) on resuscitation training in low-resource settings {Finn 2015 e203; Bhanji 2015 s242}. ILCOR suggested that alternative instructional strategies would be reasonable for teaching Basic and Advanced Life support in low-income countries (weak recommendation, very-low-quality evidence). The optimal strategy had yet to be determined.

Scientific statements and treatment recommendations have in the past been formulated from a perspective of an ideal resource environment. Little attention has been paid to the applicability of statements from such high-resource or high-income areas in the daily practice of lower-income countries and/or lower-resource emergency care systems. In many parts of the world, the standard of care from high-resource settings is not available due to the simple fact of lack of financial resources. For example, the absence of an EMS system or the low-quality performance of an EMS system {Akin Paker 2015 122; De Wulf 2015 553; El Sayed 2017; Razzak 2008 8} or the EMS system being still under development {Brown 2016 663} are barriers to the implementation of resuscitation guidelines. ILCOR’s aim of creating internationally valid statements should take into account that recommendations should also serve as a supportive structure for weaker systems {Chamberlain 1993 508}. This scoping review aims to raise awareness of gaps in emergency care services around the world, to identify gaps in the literature and to suggest future research priorities to address these gaps.

2. Narrative summary of evidence identified

The identified studies originated from diverse geographical areas, and there were large differences in the number of studies per region (e.g. 9 studies from Asia {Yingxin 2019 439; Yingying 2018 234; Guo 2017 940; Shao 2014 1411; Yang 2009 142; Krishna 2017 200; Monsomboon 2015 213; Yeeheng 2011 601; Ong 2015 100} against 3 from South America {Trevisan 2018 329; Morais 2014 562; Semensato 2011 196}, see Table 2). We did not find eligible studies from low-income countries, 4 studies were from lower-middle income countries (India 1 {Krishna 2017 200}, Pakistan 2 {Moosajee 2018; Mawani 2016}, China 1 {Yang 2009 142}), all other were from upper-middle income economies.

The number of patients reported in the studies ranged from 54 to 3214 with most studies reporting on a low number of patients, increasing the risk of imprecision bias. Only 4 studies reported data on over 1000 patients {Yingxin 2019 439; Shao 2014 1411; Navab 2019 36; Morais 2014 562}. Most data except 7 {Yingying 2018 234; Guo 2017 940; Ong 2015 100; Navab 2019 36;

Attachment Figure 1: Number of patients studied (blue) and ROSC rates in % (orange) for to included studies. X axis: first author, year of publication (country); Y axis left: number of patients studied; Y axis right: % ROSC. Guo 2017 was excluded from the figure due to the fact of only reporting a range of ROSC rates. EIT-634-figure-1

Mawani 2016; Balci 2017 254; Ozturk 2014 25} were derived from prospective or retrospective observational studies. The initial search identified RCTs that often focused on very specific (sub)-populations, often without useful information about patient outcome, such as …The Utstein-style reporting was not applied by most studies. The time of inclusion of the patients varied widely, for instance in some studies patients were included during or after CPR by the EMS whereas in other studies patients were included at ED admission, see Table 3.

The ROSC rates varied considerably between studies, from 0% to 62%. Fifteen studies (63% {Guo 2017 940; Shao 2014 1411; Yang 2009 142; Krishna 2017 200; Monsomboon 2015 213; Ong 2015 100; Navab 2019 36; Raffee 2017 436; Refaat 2019 1390; El Sayed 2014 281; Moosaiee 2018; Mawani 2016; Balci 2017 254; Sariaydin 2017 123; Semensato 2011 196} reported on longer-term outcomes such as survival to hospital discharge or neurological status. Longer-term outcomes were usually worse than those reported in patients from high-resource countries {Berdowski 2010 1479}. Figure 1 shows ROSC rates and the number of patients studied. The three largest studies {Navab 2019 36; Yingxin 2019 439; Shao 2014 1411}), reported low ROSC rates as compared to many of the small studies reporting high ROSC rates.

3. Narrative Reporting of the task force discussions

The EIT Task Force acknowledges the heterogeneity of the reported data. This may have derived from the lack of resources that EMS systems, Emergency Departments (EDs) researchers in low-resource areas can devote to standardise the reporting of outcome after resuscitation. Organisations responsible for emergency care in low-resource environments should be encouraged and supported to introduce measures of data collection, such as registries with outcome documentation, preferably also considering Utstein-style reporting. We acknowledge that there are costs associated with such data collection, and this should be prioritised locally depending on competing health expenditures. Data collection, in turn, may lead to improved comparability of data, support research specific to such settings, and generate scientific statements and recommendations specific for these areas. For future work, regional experts and clinicians should be involved in global initiatives such as ILCOR in order to maximise both local acceptability and applicability of such recommendations.

For instance, a list of essential resuscitation equipment does not exist yet but may be helpful. In 2009 the World Health Organisation (WHO) published a statement on the quality of trauma care and on assessing trauma care {WHO 2009}. This WHO statement contains a list with essential resources for trauma care. If a similar list could be developed for resuscitation care, it may be used to identify a lack of resources in some hospitals/areas/countries and to disclose disparities between income and the available of resources. Indicators may include but are not limited to: the availability of an EMS (or an EMS able to effectively transport patients to an appropriate facility), basic needs such as access to clean drinking water and electricity, availability of standardised medical equipment such as oxygen, essential drugs, neonatal bag-valve-mask devices, defibrillators, sufficiently trained staff and the presence of EDs and Intensive Care Units (ICUs). A functioning “chain of survival” should be the goal {Friesen 2015 97, Hodkinson 2010 765, Ismail 2012 115, Suryanto 2017 64}. For instance, a functioning EMS is only available to one third of African countries, reaching a mere 9% of Africans {Mould-Millman 2017 273}. The task force acknowledges that prioritising which link to develop first is a matter of local prioritisation and not something to seek consensus on globally.

Also, the question arises if prehospital resuscitation is feasible, cost-effective or even ethically justifiable in the regions considered. CPR in OHCA has limited success, even in high-income economies. Considering the scarcity of resources in low-income countries, the feasibility of full ALS and post-resuscitation care is a matter of controversy (see above). Cost-effectiveness might depend on the exact classification of the low-resource setting {Hauswald 1997 600}. Post-resuscitation care including treatment in an ICU may not be possible in all settings due to a lack of required resources. One may question whether it is ethically acceptable that ALS for OHCA patients is not available in certain countries {Stonington 2012 836}. Local determination of where to prioritize health system development should outweigh outside influence to focus on resuscitation to the detriment of other areas of health.

Globalisation and dynamics of economical situations require constant re-screening of the resource settings. Older studies may become irrelevant as low resource settings evolve.

So far, the information from the studies identified seems too heterogenous and was considered insufficient to make recommendations on OHCA in low-resource settings. However, the importance of further research and local decision-making is clear.

This scoping review has several limitations:

Our initial focus was on raising awareness of this controversial topic. We are conscious of the ILCOR EIT Task Force’s background with members exclusively living in high-income settings. Experts with a background in, or from low resource settings were consulted and gave their opinion and insights, but they did not participate in the selection of the studies and in the data extraction. For the same reason we could not consider non-English full text articles, thereby creating a selection bias. Future ILCOR work is going to focus on a more comprehensive approach, embedding the work of experts from all resource backgrounds.

Secondly, in order to generate a clearer picture of the data and to reduce heterogeneity, various exclusion criteria had to be applied (see inclusion and exclusion criteria). Thus, data from countries or regions focusing on data reporting of specific topics are missing in this review, creating a reporting bias. Future work should address these gaps (see below).

Moreover, because research requires significant resources, centers publishing scientific data might already represent areas of higher resources and special patient groups, therefore not reporting an overall picture of the whole country. On the other hand, countries listed by the World Bank as high-income may contain low-resource environments (e.g. rural areas or low-income neighborhoods). For example, northern Canada and rural Australia have known health disparities {Wakerman 2019 202} . The areas of low resources may even be restricted to single hospitals lacking training, lacking experienced staff or having insufficient financial resources. Also, even in high-income countries, temporary low-resource conditions may arise due to, for instance, natural or human-made disasters.

Knowledge Gaps

• We suggest future reviews of settings, (sub)-populations and different etiologies of OHCA that were not included in this scoping review: neonates and children (as most low-resource countries suffer high maternal and neonatal death), trauma care in low-resource settings (as several low-resource countries also have conflict zones and even war zones), drowning and intoxication in low-resource settings and in-hospital cardiac arrest.
• Differences in patient expectations and cultural/geographical differences between countries must be explored in order not only to meet economic and structural challenges, but also to address psychological and sociocultural views on the end of life, resuscitation and emergency care that might be different from high-income settings.
• As post-resuscitation care may not be available in low-resource settings, ROSC might not be the primary outcome measurement of choice. It is therefore important that also long-term outcomes including neurological performance are studied in low-resource settings.
• An in-depth comparison of ROSC rates, survival rates and neurological outcomes with data from large registries of high-income economies should be considered

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