Real Time Feedback for CPR Quality – Scoping Review (BLS 2511) ScR

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 applicable.

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: Theresa Olasveengen, Ziad Nehme and Fredrick Folke are authors on included papers.

Task Force Synthesis Citation

Masterson S, Norii T, Ikeyama T, Nehme Z, Considine J, Olasveengen T, Bray J, on behalf of the International Liaison Committee on Resuscitation Basic Life Support Task Force. Real-Time Feedback for Cardiopulmonary Resuscitation Task Force Synthesis of a Scoping Review [Internet] Brussels, Belgium: International Liaison Committee on Resuscitation (ILCOR) Advanced Life Support Task Force, 2023 Jan 8. Available from: http://ilcor.org. The BLS Task Force acknowledge the expert assistance of Brendan Leen, Librarian, Irish Health Service Executive, who assisted with the design of the search strategy and conducted the search of electronic databases.

Methodological Preamble

The continuous evidence evaluation process started with a scoping review of the impact of real-time feedback for cardiopulmonary resuscitation (CPR) quality on patient outcomes by the ILCOR BLS Task Force Scoping Review Team. Evidence for literature was sought and considered by the BLS Task Force.

PICOST

Population: Adults and children (excluding neonates) in any setting (in-hospital or out-of-hospital) with cardiac arrest who are resuscitated by health professionals responding in a professional capacity.

Intervention: Real-time feedback and prompt devices regarding the mechanics of CPR quality (e.g. rate and depth of compressions and/or ventilations)

Comparators: No real-time feedback and prompt devices or alternative real-time feedback and prompt devices.

Outcomes: Any patient outcome or measure of CPR quality.

Study Designs: Randomized controlled trials (RCTs) and non-randomized studies (non-randomized controlled trials, interrupted time series, controlled before-and-after studies, cohort studies) are eligible for inclusion. Case series were included in the initial search. Grey literature and non-peer reviewed studies, unpublished studies, conference abstracts and trial protocols were eligible for inclusion. All relevant publications in any language are included as long as there was an English abstract.

Timeframe: All years.

Literature search updated to 18 July, 2023.

Search Strategies

Articles for review were obtained by searching PubMed, EMBASE, Cochrane, and Allied Health Literature (CINAHL), for all entries from database inception to 18 July 2023. A grey literature search was performed in the Google search engine.

Articles are using key terms “heart arrest”, “heart or cardiac or cardio* or coronary”, “arrest or failure or standstill or cessation or stoppage”, "asystol*”, “sudden cardiac death”, “resuscitation”, "cardiopulmonary resuscitation", "cardiopulmonary arrest", “CPR”, “CPA”, "cardiac massage", "heart massage”, “feedback”, “feed-back”, “feed back”, “CPR-sensing”, “Q-CPR”, “CPR-plus”, “CPREzy”, “CPR-Ezy”, “high performance cardiopulmonary resuscitation”, “high performance resuscitation”, “prompt*”, “sensor*”, “metronome”, “real time”, “realtime”, “resuscitat*”; including their MESH terms, and Embase exploded terms.

Inclusion and Exclusion criteria

During abstract screening, items were not excluded based on the article type. During full-text review, simulation studies, commentaries and opinion pieces that did not cite references related to real-time CPR feedback were excluded. During full-text review, poster abstracts were excluded if the data presented was subsequently published as a full study that had been identified in our search strategy. Reference lists in systematic reviews were used to validate our search results i.e. to check that relevant articles had been identified in our search strategy. Articles that referred to real-time CPR feedback but did not include any results relating to CPR quality or patient outcomes were also excluded. Finally, articles relating to the use of real-time feedback during resuscitation of neonates were excluded as the ILCOR Neonatal Life Support Task Force completed a scoping review in the same topic in January 2023.

In total, we identified 4,211 articles. After de-duplication, the total number of articles screened was 2,351. We identified 74 articles for full-text review. We excluded 15 articles at this stage:

• Not real-time feedback = 4
• Not relevant to CPR feedback = 2
• Simulation study = 3
• Animal and Human Studies, not possible to extract human only = 1
• Duplicate studies = 4
• CPR feedback not described in the article = 1
• Abstract or full text not available in English = 2
• Related to mechanical CPR = 1
• Not CPR by healthcare professionals = 1

We included 55 articles in the final review.

Data tables: 2511 Feedback for CPR quality Sc R 2024 Data tables

Task Force Insights

1. Why this topic was reviewed.

• The quality of cardiopulmonary resuscitation (CPR) directly impacts survival and neurological outcomes for people in cardiac arrest. Despite extensive studies and numerous quality improvement projects, how to improve the quality of CPR has remained a significant issue in both out-of-hospital and in-hospital settings. Previous studies have identified challenges of consistently performing high-quality CPR, even among highly trained healthcare professionals.
• Real-time CPR feedback has been studied as a potential method not only to improve the quality of CPR, but also survival and neurological outcomes of victims of cardiac arrest. However, the results of these studies have been mixed and implementation of real-time CPR feedback in the clinical setting is somewhat limited globally.
• The topic of the impact of real-time feedback for CPR quality on patient clinical outcomes was systematically reviewed in 2020.
• While a systematic review of this topic was planned for 2022, the Taskforce was conscious that the literature in relation to system quality improvement and high performance CPR had expanded in recent years, and that real-time CPR feedback was often included as part of these programs. Additionally, the Taskforce believed that future systematic reviews should focus on provision of CPR by health professionals responding in a professional capacity, rather than bystanders or lay responders. Furthermore, the Neonatal Life Support Taskforce completed a scoping review in the same topic in January 2023. For these reasons the following modifications were made to the 2020 SR PICOST (Table below).
• The Task Force decided to perform a scoping review to understand if the wider literature may provide further insights into the effectiveness of feedback and improve the existing PICOST.
• Many studies were excluded from the 2020 ILCOR review as they combined the evaluation of feedback with other quality improvement activities (e.g. debriefing). The Task Force decided to perform a scoping review to understand if the wider literature, including studies with other interventions, may provide further insights into the effectiveness of feedback and improve the existing PICOST.

PICOST with 2023 changes highlighted in yellow

2. Narrative summary of evidence identified

• Of the 55 studies included in the narrative synthesis, we found 5 RCTs^1-5 related to the impact real-time CPR feedback on patient outcomes, only one of which has been published after 2019. Three studies reported that real-time feedback on CC quality did not significantly improve patient outcomes. ^1-3 One study, using the Cardio First Angel (CFA), ⁴ conducted with patients admitted to ICU from the ED found that patient outcomes were significantly improved in the CFA group: (66.7% vs. 42.4%, P < 0.001); survival to ICU discharge (59.8% vs. 33.6%); survival to hospital discharge (54% vs. 28.4%, P < 0.001). Similarly, Vahedin-Azimi (2016) found that real-time AV feedback improved CPR quality and outcomes for patients in ICUs (ROSC was observed more frequently in the intervention group (72% vs. 35%; p = 0.001).⁵
• Ten systematic reviews were identified.^6-15 Three meta-analyses investigated the impact of ‘system performance improvement’, ‘implementation of high performance CPR’ and ‘quality improvement systems’.^8,9,12 One review that examined the impact of real-time feedback on training and CPR performance found that feedback improved CPR quality but no direct impact on survival to discharge rates.⁶ One systematic review looked at the impact of metronome use on CPR quality but did not look at the impact on patient outcomes.¹⁴ The remaining five reviews investigated the effect of real-time feedback on patient outcomes. Kirkbright (2014) also include manikin studies but reported human studies separately.⁷ For 3 human studies, they found no significant improvement in patient outcomes, but significant improvements in chest compression rate, depth and no-flow fraction. In OHCA patients, Lyngby (2021) found that real-time feedback improved chest compression depth and rate but did not statistically improve patient outcomes.¹¹ Pooled analysis by Lv (2022) found that real-time feedback did not improve ROSC, was associated with improved survival to discharge but not with good neurological outcome at discharge.¹³ A similar review by Wang (2020) found that improved survival to discharge was found only in studies where the Cardio First Angel device was used. ¹⁵ Miller (2020) found that ‘free-standing non-AED AV feedback devices’ were associated with improved outcomes.¹⁰
• The vast majority of studies that described some aspect of real-time feedback for CPR were observational (n=34). Thirteen studies described real-time feedback as part of overall system improvements.^16-28 Of the seven studies that described CPR quality, all reported that at least some aspects of CPR quality had improved as a result of the intervention. Results on the impact on patient outcomes were more mixed, but the majority of the thirteen studies reported some degree of positive impact on patient outcomes. Sixteen studies almost invariably reported an improvement in some aspect of CPR quality but did not find a consequent improvement in patient outcomes. ^29-44 Four studies investigated the impact of real-time feedback in out-of-hospital settings. ^45-48 With the exception of a statistically significant improvement in ROSC rates in one study, ⁴⁸ improved patient outcomes were not reported. One study investigating the impact of a CPR coach giving corrective verbal feedback in pediatric IHCA and found an improvement in ROSC rates in centres with a CPR coach. ⁴⁹
• Two studies investigated the impact of real-time feedback on leaning during CPR. ^50,51 While real-time feedback was associated with reduced leaning, the association between leaning, CPR quality and patient outcomes was not clear. One study investigated the use of carotid ultrasound. The main objective was to investigate the general feasibility of carotid US during CPR measures. ⁵²
• The two remaining studies were case series, one providing a description of chest wall damage as a result of using a feedback sensor, ⁵³ and one describing the impact of real-time feedback on hemodynamic parameters in a child who suffered cardiac arrest secondary to drowning. ⁵⁴ The remaining paper was a commentary on the potential of trans esophageal echocardiography as a potential source of CPR feedback. ⁵⁵

3. Narrative Reporting of the task force discussions

• While 55 studies were included in the narrative synthesis, there was insufficient new evidence available to recommend a systematic review using the expanded PICOST. In summary, we conclude there were insufficient studies identified to support a more specific systematic review. An update of the systematic review using the existing PICOST is recommended.
• This scoping review has revealed a substantial adjacent literature on implementing high performance CPR/QI programs that is associated with improved clinical outcomes but it is not possible to extract a specific association with real-time CPR feedback from these studies. It is suggested that a new PICOST is developed that examines the impact of these programs on clinical outcomes for both OHCA and IHCA patients.

Knowledge Gaps

Knowledge Gaps Template for Task Force chairs

While a scoping review is not designed to consider the quality of studies, it is clear that there is a dearth of high-quality studies on real-time CPR feedback.

References

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2. Hostler D, Everson-Stewart S, Rea TD, et al. Effect of real-time feedback during cardiopulmonary resuscitation outside hospital: prospective, cluster-randomised trial. Bmj. Feb 4 2011;342:d512. doi:10.1136/bmj.d512

3. Vahedian-Azimi A, Rahimibashar F, Miller AC. A comparison of cardiopulmonary resuscitation with standard manual compressions versus compressions with real-time audiovisual feedback: A randomized controlled pilot study. Int J Crit Illn Inj Sci. Jan-Mar 2020;10(1):32-37. doi:10.4103/ijciis.ijciis_84_19

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5. Vahedian-Azimi A, Hajiesmaeili M, Amirsavadkouhi A, et al. Effect of the Cardio First Angel™ device on CPR indices: a randomized controlled clinical trial. Crit Care. May 17 2016;20(1):147. doi:10.1186/s13054-016-1296-3

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