Improvement in chest compression quality using a feedback device (CPRmeter): a simulation randomized crossover study

The effect of standalone audio-visual feedback devices on the quality of chest compressions during laypersons' cardiopulmonary resuscitation training: a systematic review and meta-analysis

AIMS

Individual studies that investigated the effect of standalone audio-visual feedback (AVF) devices during laypersons' cardiopulmonary resuscitation (CPR) training have yielded conflicting results. This review aimed to evaluate the effect of standalone AVF devices on the quality of chest compressions during laypersons' CPR training.

METHOD AND RESULT

Randomized controlled trials of simulation studies recruiting participants without actual patient CPR experience were included. The intervention evaluated was the quality of chest compressions with standalone AVF devices vs. without AVF devices. Databases, such as PubMed, Cochrane Central, Embase, Cumulative Index to Nursing & Allied Health Literature (CINAHL), Web of Science, and PsycINFO, were searched from January 2010 to January 2022. The risk of bias was assessed using the Cochrane risk of bias tool. A meta-analysis alongside a narrative synthesis was used for examining the effect of standalone AVF devices.Sixteen studies were selected for this systematic review. A meta-analysis revealed an increased compression depth of 2.22 mm [95% CI (Confidence Interval), 0.88-3.55, P = 0.001] when participants performed CPR using the feedback devices. Besides, AVF devices enabled laypersons to deliver compression rates closer to the recommended range of 100-120 per min. No improvement was noted in chest recoil and hand positioning when participants used standalone AVF devices.

CONCLUSION

The quality of the included studies was variable, and different standalone AVF devices were used. Standalone AVF devices were instrumental in guiding laypersons to deliver deeper compressions without compromising the quality of compression rates. However, the devices did not improve the quality of chest recoil and placement of the hands.

REGISTRATION

PROSPERO: CRD42020205754.

Effect of real-time feedback device compared to use or non-use of a checklist performance aid on post-training performance and retention of infant cardiopulmonary resuscitation: A randomized simulation-based trial

INTRODUCTION

This study aims to determine the best method for achieving optimal performance of pediatric cardiopulmonary resuscitation (CPR) during simulation-based training, whether with or without a performance aid.

METHODS

In this randomized controlled study, 46 participants performed simulated CPR in pairs on a Resusci Baby QCPR™ mannequin, repeated after four weeks. All participants performed the first simulation without performance aids. For the second simulation, they were randomly assigned to one of three groups with stratification based on status: throughout CPR, Group A (n = 16) was the control group and did not use a performance aid; Group B (n = 16) used the CPR checklist; Group C (n = 14) used real-time visualization of their CPR activity on a feedback device. Overall performance was assessed using the QCPR™.

RESULTS

All groups demonstrated improved performance on the second simulation (p < 0.01). Use of the feedback device resulted in better CPR performance than use of the CPR checklist (p = 0.02) or no performance aid (p = 0.04). Additionally, participants thought that the QCPR™ could effectively improve their technical competences.

CONCLUSIONS

Performance aid based on continuous feedback is helpful in the learning process. The use of the QCPR™, a real-time feedback device, improved the quality of resuscitation during infant CPR simulation-based training.

An Evaluation of the Quality of CPR Chest Compressions Performed on Football-Equipped and Obese Simulation Manikins

OBJECTIVE

Protective athletic equipment may hamper the delivery of effective chest compressions. Unfortunately, an algorithm for managing cardiac arrest emergencies with equipment-laden athletes has yet to be established by national CPR certifying agencies. Further, athletes classified as being overweight or obese carry adipose in the thoracic region, which has been reported to inhibit the ability of rescuers to provide quality chest compressions. Thus, the purpose of this study was two-fold. The first purpose was to assess the ability of emergency responders to perform CPR chest compressions on an obese manikin. The second purpose was to analyze the effect of American football protective equipment on the performance of chest compressions by emergency responders.

METHODS

Fifty emergency responders completed four 2-minute bouts of compression-only CPR. The scenarios included performing chest compressions on both traditional and obese CPR manikins, and performing chest compressions over a set of shoulder pads/chest protector that is used in the sport of American football on both traditional and obese manikins.

RESULTS

The most notable outcomes in this study were related to chest compression depth, which fell well below the minimum recommended depth published by the American Heart Association in all conditions. Mean compression depth was significantly lower when performed on the obese manikin (avg over pads = 32.8, SD = 9.2 mm; avg no pads = 38.2, SD = 9.1 mm) compared to the traditional manikin (avg over pads = 40.0, SD = 10.9 mm; avg no pads = 40.8, SD = 14.8 mm), with statistical analyses revealing a significant effect due to both manikin size (p < 0.001) and the presence of equipment (p = 0.003), and a statistically significant interaction effect (p = 0.035). Chest recoil data revealed a statistically significant effect due to both manikin size (p = 0.017) and the presence of chest/shoulder safety pads (p = 0.003).

CONCLUSION

Within this sample of emergency responders, chest compressions were adversely affected both by the equipment and obesity. Additionally, the traditional manikin received comparable chest compressions regardless of the presence or absence of football protective equipment, albeit both conditions resulted in poor depth performance.

Simulation-Based Training in High-Quality Cardiopulmonary Resuscitation Among Neonatal Intensive Care Unit Providers

INTRODUCTION

American Heart Association guidelines recommend the use of feedback devices for CPR provider resuscitation training. There is paucity of published literature regarding the utility of these devices especially in neonates and infants. We sought to evaluate if simulation-based education and debriefing using a CPR feedback device would improve CPR performance on an infant manikin in a cohort of NICU nurses as evaluated by CPR feedback device.

METHODS

We conducted a prospective, observational simulation study to assess the quality of chest compressions by NICU nurses before and after debriefing using CPR quality data captured by an accelerometer-based device. Chest compression (CC) depth, rate, recoil, CC fraction and nursing confidence level related to performing a high-quality CPR were compared before and after debriefing using paired t-test and Wilcoxon rank sum test.

RESULTS

A total of 62 NICU nurses participated in the study and all of them were Neonatal Resuscitation Program (NRP) certified. There was a significant improvement in CC depth and CC fraction [mean + SD values = 0.79 in + 0.17 (pre-debrief), 0.86 in + 0.21 (post-debrief) (p = 0.034) and 56.8% + 17.7 (pre-debrief), 70.8% + 18.4 (post-debrief) (0.0014), respectively]. There was no difference in CC rate (p = 0.36) and recoil (p = 0.25) between pre and post structured debriefing. The confidence level of nurses in all CPR dynamics (appropriate CC rate, CC depth, team communication, minimizing interruption in CC and coordinating CC with ventilation) was significantly higher after simulation and structured debriefing. All the nurses used 3:1 compression: ventilation ratio of NRP despite the patient being a 4 month old premature baby in the NICU.

CONCLUSIONS

Simulation training and debriefing of NICU nurses using CPR feedback device improved their chest compression quality on an infant mannequin and their confidence level for performing high-quality CPR. NICU providers tend to use NRP protocol of 3:1 compression: ventilation ratio during CPR in the NICU irrespective of age of the infant.

The impact of bystander cardiopulmonary resuscitation on patients with out-of-hospital cardiac arrests

Out-of-hospital cardiac arrest (OHCA) is one of the leading causes of death around the world. Bystander cardiopulmonary resuscitation (CPR) is an independent factor to improve OHCA survival. However, the prevalence of bystander CPR remains low worldwide. Community interventions such as mandatory school CPR training or targeting CPR training to family members of high-risk cardiac patients are possible strategies to improve bystander CPR rate. Real-time feedback, hands-on practice with a manikin, and metronome assistance may increase the quality of CPR. Dispatcher-assistance and compression-only CPR for untrained bystanders have shown to increase bystander CPR rate and increase survival to hospital discharge. After return of spontaneous circulation, targeted temperature management should be performed to improve neurological function. This review focuses on the impact of bystander CPR on clinical outcomes and strategies to optimize the prevalence and quality of bystander CPR.

Effects of airway management and tidal volume feedback ventilation during pediatric resuscitation in piglets with asphyxial cardiac arrest

To compare the effect on the recovery of spontaneous circulation (ROSC) of early endotracheal intubation (ETI) versus bag-mask ventilation (BMV), and expiratory real-time tidal volume (VTe) feedback (TVF) ventilation versus without feedback or standard ventilation (SV) in a pediatric animal model of asphyxial cardiac arrest. Piglets were randomized into five groups: 1: ETI and TVF ventilation (10 ml/kg); 2: ETI and TVF (7 ml/kg); 3: ETI and SV; 4: BMV and TVF (10 ml/kg) and 5: BMV and SV. Thirty breaths-per-minute guided by metronome were given. ROSC, pCO2, pO2, EtCO2 and VTe were compared among groups. Seventy-nine piglets (11.3 ± 1.2 kg) were included. Twenty-six (32.9%) achieved ROSC. Survival was non-significantly higher in ETI (40.4%) than BMV groups (21.9%), p = 0.08. No differences in ROSC were found between TVF and SV groups (30.0% versus 34.7%, p = 0.67). ETI groups presented lower pCO2, and higher pO2, EtCO2 and VTe than BMV groups (p < 0.05). VTe was lower in TVF than in SV groups and in BMV than in ETI groups (p < 0.05). Groups 1 and 3 showed higher pO2 and lower pCO2 over time, although with hyperventilation values (pCO2 < 35 mmHg). ETI groups had non significantly higher survival rate than BMV groups. Compared to BMV groups, ETI groups achieved better oxygenation and ventilation parameters. VTe was lower in both TVF and BMV groups. Hyperventilation was observed in intubated animals with SV and with 10 ml/kg VTF.

Effects of the non-contact cardiopulmonary resuscitation training using smart technology

Aims

Accurate cardiopulmonary resuscitation (CPR) performance is an essential skill for nursing students so they need to learn the skill correctly from the beginning and carry that forward with them into their clinical practice. For the new normal after coronavirus disease 2019 (COVID-19), safe training modules should be developed. This study aimed to develop non-contact CPR training using smart technology for nursing students and to examine its effects, focusing on the accuracy of their performance. The study used a prospective, single-blind, randomized, and controlled trial with repeated measures.

Methods and results

The non-contact CPR training with smart technology consisted of a 40-min theoretical online lecture session and an 80-min non-contact practice session with real-time feedback devices and monitoring cameras. Sixty-four nursing students were randomly assigned to either an experimental group (n = 31) using non-contact training or a control group (n = 33) using general training. The accuracy of chest compression and mouth-to-mouth ventilation, and overall performance ability were measured at pretest, right after training, and at a 4-week post-test. The non-contact CPR training significantly increased the accuracy of chest compression (F = 63.57, P < 0.001) and mouth-to-mouth ventilation (F = 33.83, P < 0.001), and the overall performance ability (F = 35.98, P < 0.001) compared to the general CPR training over time.

Conclusions

The non-contact CPR training using smart technology help nursing students develop their techniques by self-adjusting compression depth, rate, release and hand position, and ventilation volume and rate in real time. Nursing students can learn CPR correctly through the training allowing real-time correction in safe learning environments without face-to-face contact.

Real-time audio-visual feedback with handheld nonautomated external defibrillator devices during cardiopulmonary resuscitation for in-hospital cardiac arrest: A meta-analysis

Objective:

Restoring cardiopulmonary circulation with effective chest compression remains the cornerstone of resuscitation, yet real-time compressions may be suboptimal. This project aims to determine whether in patients with in-hospital cardiac arrest (IHCA; population), chest compressions performed with free-standing audiovisual feedback (AVF) device as compared to standard manual chest compression (comparison) results in improved outcomes, including the sustained return of spontaneous circulation (ROSC), and survival to the intensive care unit (ICU) and hospital discharge (outcomes).

Methods:

Scholarly databases and relevant bibliographies were searched, as were clinical trial registries and relevant conference proceedings to limit publication bias. Studies were not limited by date, language, or publication status. Clinical randomized controlled trials (RCT) were included that enrolled adults (age ≥ 18 years) with IHCA and assessed real-time chest compressions delivered with either the standard manual technique or with AVF from a freestanding device not linked to an automated external defibrillator (AED) or automated compressor.

Results:

Four clinical trials met inclusion criteria and were included. No ongoing trials were identified. One RCT assessed the Ambu CardioPump (Ambu Inc., Columbia, MD, USA), whereas three assessed Cardio First Angel™ (Inotech, Nubberg, Germany). No clinical RCTs compared AVF devices head-to-head. Three RCTs were multi-center. Sustained ROSC (4 studies, n = 1064) was improved with AVF use (Relative risk [RR] 1.68, 95% confidence interval [CI] 1.39–2.04), as was survival to hospital discharge (2 studies, n = 922; RR 1.78, 95% CI 1.54–2.06) and survival to hospital discharge (3 studies, n = 984; RR 1.91, 95% CI 1.62–2.25).

Conclusion:

The moderate-quality evidence suggests that chest compressions performed using a non-AED free-standing AVF device during resuscitation for IHCA improves sustained ROSC and survival to ICU and hospital discharge.

Trial Registration:

PROSPERO (CRD42020157536).

External Cardiac Massage Training of Medical Students: A Randomized Comparison of Two Feedback Methods to Standard Training

BACKGROUND

The most recent recommendations support learning of external cardiac massage (ECM) through feedback devices.

OBJECTIVES

The objective was to compare the effects on immediate and 3-month retention of ECM technical skills when using feedback devices compared with training without feedback as part of a half-day training session in medical students.

METHODS

This randomized study was performed using the Resusci Anne QCPR manikin in 64 medical students. We compared the quality of ECM with nonfeedback training in the control group (group 1) vs. 2 feedback learning methods (group 2, PocketCPR and group 3, Skill Reporter each used with visual display available to the trainee). At the end of the training session and 3 months later, students performed chest compressions blindly during a 2-min assessment session. The median compression score was the primary outcome for assessing immediate and long-term retention.

RESULTS

Regarding immediate retention, the median compression score was significantly lower in group 1 (23%) than in groups 2 (81%) and 3 (72%) (p < 0.05) with no difference between the 2 feedback methods. At 3 months, mean compression scores remained high but not significantly different between the 2 feedback groups.

CONCLUSION

The use of a feedback device used for ECM training improves the quality of immediate retention of technical ECM skills compared with traditional teaching in medical students. At 3 months, the 2 groups with feedback retained a high level of performance. No significant difference could be demonstrated between the 2 feedback methods.

Verbal Motivation vs. Digital Real-Time Feedback during Cardiopulmonary Resuscitation: Comparing Bystander CPR Quality in a Randomized and Controlled Manikin Study of Simulated Cardiac Arrest

OBJECTIVE

The use of smartphone applications increases bystander CPR quality as well as the use of telephone CPR protocols. The present prospective, randomized, controlled manikin trial analyses the effects of a smartphone application (PocketCPR©) on CPR quality in a bystander CPR scenario compared to a dispatcher-assisted telephone CPR with the additional use of a metronome and verbal motivation. Methods: 150 laypersons were included to perform 8-minute CPR on a manikin. Volunteers were randomly assigned to one of three groups: (1) dispatcher-assisted telephone CPR (telephone-group), (2) dispatcher-assisted telephone CPR combined with the smartphone-application (telephone + app-group) and (3) dispatcher-assisted telephone CPR with additional verbal motivation ("push harder, release completely," every 20 seconds, starting after 60 seconds) and a metronome with 100 min^-1 (telephone + motivation-group). Results: Median compression depth did not differ significantly between the study groups (p = 0.051). However, in the post hoc analysis median compression depth in the telephone + motivation-group was significantly elevated compared to the telephone + app-group (59 mm [IQR 47-67 mm] vs. 51 mm [IQR 46-57 mm]; p = 0.025). The median number of superficial compressions was significantly reduced in the telephone + motivation-group compared to the telephone + app-group (70 [IQR 3-362] vs. 349 [IQR 88-538]; p = 0.004), but not compared to the telephone-group (91 [IQR 4-449]; p = 0.707). In contrast to the other study groups, median compression depth of the telephone + motivation-group increased over time. Chest compressions with correct depth were found significantly more often in the telephone + app-group compared to the other study groups (p = 0.011). Median compression rate in the telephone + app-group was significantly elevated (108 min^-1 [IQR 96-119 min^-1]) compared to the telephone-group (78 min^-1 [IQR 56-106 min^-1]; p < 0.001) and the telephone + motivation-group (99 min^-1 [IQR 91-101 min^-1]; p < 0.001). Conclusions: The use of a smartphone application as well as verbal motivation by a dispatcher during telephone CPR leads to higher CPR quality levels compared to standard telephone CPR. Thereby, the use of the smartphone application mainly shows an increase in compression rate, while increased compression rate with simultaneously increased compression depth was only apparent in the telephone + motivation-group.

Quantification of Passive Ventilation Produced by Manual Chest Compressions Using a New Cardiopulmonary Resuscitation Feedback Device

Several studies have shown that chest compressions (CC) alone may produce in addition to blood circulation, a short-term passive ventilation. However, it is not clear whether high CC quality may produce in even greater amount of ventilation volumes. The aim of this study was to evaluate whether CC, using a new feedback device, can produce a substantial and sustainable passive volumes compared to standard CC. Thirty inexperienced volunteers performed CC for 2 min on a developed thoracic lung model and using a new feedback device. Participants were randomized into two groups that performed either CC with feedback first, followed by a trial without feedback, or vice versa. Efficient compression rate (correct CC rate and depth simultaneously) was significantly higher in feedback session (43.6% versus 25.5%; P = 0.006). As well, CC rate and depth efficiency were improved with feedback. Moreover, average tidal volumes and minute volumes that occurred during CC alone were significantly improved in feedback session (79.8 ± 5 ml versus 72.9 ± 7 ml) and (8.8 l/min versus 7.9 l/min), respectively (P &lt; 0.001). Yet, no significant difference was found between the first and the 90th second interval (9.04 l/min versus 8.68 l/min, P = 0.163) in the feedback session. Conversely, a significant difference was evident after the first 15th seconds interval without feedback (8.77 l/min initially versus 8.38 l/min; P = 0.041). This study revealed that the new CPR feedback device improved CC quality in inexperienced volunteers. As well, the passive ventilation volumes were significantly increased and sustained when the device was used.

Smartwatch feedback device for high-quality chest compressions by a single rescuer during infant cardiac arrest: a randomized, controlled simulation study

OBJECTIVE

According to the guidelines, rescuers should provide chest compressions (CC) ~1.5 inches (40 mm) for infants. Feedback devices could help rescuers perform CC with adequate rates (CCR) and depths (CCD). However, there is no CC feedback device for infant cardiopulmonary resuscitation (CPR). We suggest a smartwatch-based CC feedback application for infant CPR.

PARTICIPANTS AND METHODS

We created a smartwatch-based CC feedback application. This application provides feedback on CCD and CCR by colour and text for infant CPR. To evaluate the application, 30 participants were divided randomly into two groups on the basis of whether CC was performed with or without the assistance of the smartwatch application. Both groups performed continuous CC-only CPR for 2 min on an infant mannequin placed on a firm table. We collected CC parameters from the mannequin, including the proportion of correct depth, CCR, CCD and the proportion of correct decompression depth.

RESULTS

Demographics between the two groups were not significantly different. The median (interquartile range) proportion of correct depth was 99 (97-100) with feedback compared with 83 (58-97) without feedback (P = 0.002). The CCR and proportion of correct decompression depth were not significantly different between the two groups (P = 0.482 and 0.089). The CCD of the feedback group was significantly deeper than that of the control group [feedback vs. control: 41.2 (39.8-41.7) mm vs. 38.6 (36.1-39.6) mm; P=0.004].

CONCLUSION

Rescuers who receive feedback of CC parameters from a smartwatch could perform adequate CC during infant CPR.

Implementation of Chest Compression Feedback Technology to Improve the Quality of Cardiopulmonary Resuscitation in the Emergency Department: A Quality Initiative Test-of-change Study

Background

Cardiopulmonary resuscitation (CPR) metrics including compression rate and depth are associated with improved outcomes and the need for high-quality CPR is emphasized in both the American Heart Association (AHA) and Heart and Stroke Foundation of Canada (HSFC) guidelines. While these metrics can be utilized to assess the quality of CPR, they are infrequently measured in an objective fashion in the emergency department.

Objectives

As part of an Emergency Department (ED) Quality Improvement (QI) project, we sought to determine the impact of real-time audio-visual (AV) feedback during CPR amongst ED healthcare providers.

Methods

Participants performed two minutes of uninterrupted CPR without AV feedback, followed by two minutes of CPR with AV feedback after a two-minute rest period in a simulated CPR setting. CPR metrics were captured by the defibrillator and uploaded to review software for analysis of each event.

Results

The use of real-time AV feedback resulted in a significant improvement in the number of participants meeting AHA/HSFC recommended depth (38%, p = 0.0003) and rate (35%, p = 0.0002). Importantly, ‘compressions in target’, where participants met both rate and depth simultaneously, improved with AV feedback (19 vs 61%, p < 0.0001).

Conclusions

We found a significant improvement in compliance with CPR depth and rate targets as well as ‘compressions in target’ with the use of real-time AV feedback during simulation training. Future research is needed to ascertain whether these results would be replicated in other settings. Our findings do provide a robust argument for the implementation of real-time AV CPR feedback in Hamilton Emergency Departments.

U, Ruetzler K. The TrueCPR device in the process of teaching cardiopulmonary resuscitation: A randomized simulation trial

BACKGROUND

International resuscitation guidelines emphasize the importance of high quality chest compressions, including correct chest compression depth and rate and complete chest recoil. The aim of the study was to assess the role of the TrueCPR device in the process of teaching cardiopulmonary resuscitation in nursing students.

METHODS

A prospective randomized experimental study was performed among 94 first year students of nursing. On the next day, the participants were divided into 2 groups-the control group practiced chest compressions without the use of any device for half an hour, and the experimental group practiced with the use of TrueCPR. Further measurement of chest compressions was performed after a month.

RESULTS

The chest compression rate achieved the value of 113 versus 126 (P < .001), adequate chest compression rate (%) was 86 versus 68 (P < .001), full chest release (%) 92 versus 69 (P = .001), and correct hand placement (%) 99 versus 99 (P, not significant) in TrueCPR and standard BLS groups, respectively. As for the assessment of the confidence of chest compression quality, 1 month after the training, the evaluation in the experimental group was statistically significantly higher (91 vs 71; P < .001) than in the control group.

CONCLUSIONS

Cardiopulmonary resuscitation training with the use of the TrueCPR device is associated with better resuscitation skills 1 month after the training. The participants using TrueCPR during the training achieved a better chest compression rate and depth with in international recommendations and better full chest release percentage and self-assessed confidence of chest compression quality comparing with standard cardiopulmonary resuscitation training.

Effect of real-time visual feedback device 'Quality Cardiopulmonary Resuscitation (QCPR) Classroom' with a metronome sound on layperson CPR training in Japan: a cluster randomized control trial

OBJECTIVES

'Quality Cardiopulmonary Resuscitation (QCPR) Classroom' was recently introduced to provide higher-quality Cardiopulmonary Resuscitation (CPR) training. This study aimed to examine whether novel QCPR Classroom training can lead to higher chest-compression quality than standard CPR training.

DESIGN

A cluster randomised controlled trial was conducted to compare standard CPR training (control) and QCPR Classroom (intervention).

SETTING

Layperson CPR training in Japan.

PARTICIPANTS

Six hundred forty-two people aged over 15 years were recruited from among CPR trainees.

INTERVENTIONS

CPR performance data were registered without feedback on instrumented Little Anne prototypes for 1 min pretraining and post-training. A large classroom was used in which QCPR Classroom participants could see their CPR performance on a big screen at the front; the control group only received instructor's subjective feedback.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcomes were compression depth (mm), rate (compressions per minute (cpm)), percentage of adequate depth (%) and recoil (%). Survey scores were a secondary outcome. The survey included participants' confidence regarding CPR parameters and ease of understanding instructor feedback.

RESULTS

In total, 259 and 238 people in the control and QCPR Classroom groups, respectively, were eligible for analysis. After training, the mean compression depth and rate were 56.1±9.8 mm and 119.2±7.3 cpm in the control group and 59.5±7.9 mm and 116.8±5.5 cpm in the QCPR Classroom group. The QCPR Classroom group showed significantly more adequate depth than the control group (p=0.001). There were 39.0% (95% CI 33.8 to 44.2; p<0.0001) and 20.0% improvements (95% CI 15.4 to 24.7; P<0.0001) in the QCPR Classroom and control groups, respectively. The difference in adequate recoil between pretraining and post-training was 2.7% (95% CI -1.7 to 7.1; pre 64.2±36.5% vs post 66.9%±34.6%; p=0.23) and 22.6% in the control and QCPR Classroom groups (95% CI 17.8 to 27.3; pre 64.8±37.5% vs post 87.4%±22.9%; p<0.0001), respectively.

CONCLUSIONS

QCPR Classroom helped students achieve high-quality CPR training, especially for proper compression depth and full recoil. For good educational achievement, a novel QCPR Classroom with a metronome sound is recommended.

Using a smartphone application (PocketCPR) to determine CPR quality in a bystander CPR scenario - A manikin trial

PURPOSE OF THE STUDY

Feedback devices and dispatcher assistance increase CPR quality in bystander resuscitation. Yet, there is no data comparing both approaches with uninstructed CPR. The present prospective, randomized, controlled, manikin trial aims to determine the effects of the use of a smartphone application (PocketCPR) on CPR quality in a bystander CPR scenario compared to dispatcher-assisted telephone CPR and uninstructed CPR.

METHODS

100 laypersons were included to perform 8-min CPR on a manikin. Volunteers were randomly assigned to one of four groups: (1) uninstructed CPR (uninstructed group), (2) dispatcher-assisted telephone CPR (telephone-group), (3) guidance and feedback through a smartphone application (app-group) and (4) dispatcher-assisted telephone CPR combined with the smartphone-app (telephone + app-group).

RESULTS AND DISCUSSION

There was no significant difference in the time to first compression between the uninstructed and the app-group (p = 0.052), likewise between the telephone- and the telephone + app-group (p = 0.193). The no-flow-time of the uninstructed group was significantly longer compared to all other groups (p < 0.001). Median compression rate was significantly higher and within the recommended range in the app- and the telephone + app-group. There was no significant difference regarding correct compression depth between the four groups. Correct hand position and complete thorax release was found significantly more frequently in groups with smartphone-app support.

CONCLUSIONS

Feedback by a smartphone application can improve bystander CPR quality in terms of no-flow-time, compression rate, correct hand position, thorax release and does not delay CPR onset. However, the use of a smartphone application does not improve compression depth significantly.

Interventions to improve the quality of bystander cardiopulmonary resuscitation: A systematic review

Background

Performing high-quality bystander cardiopulmonary resuscitation (CPR) improves the clinical outcomes of victims with sudden cardiac arrest. Thus far, no systematic review has been performed to identify interventions associated with improved bystander CPR quality.

Methods

We searched Ovid MEDLINE, Ovid EMBASE, EBSCO CINAHL, Ovid PsycInfo, Thomson Reuters SCI-EXPANDED, and the Cochrane Central Register of Controlled Trials to retrieve studies published from 1 January 1966 to 5 October 2018 associated with interventions that could improve the quality of bystander CPR. Data regarding participant characteristics, interventions, and design and outcomes of included studies were extracted.

Results

Of the initially identified 2,703 studies, 42 were included. Of these, 32 were randomized controlled trials. Participants included adults, high school students, and university students with non-medical professional majors. Interventions improving bystander CPR quality included telephone dispatcher-assisted CPR (DA-CPR) with simplified or more concrete instructions, compression-only CPR, and other on-scene interventions, such as four-hand CPR for elderly rescuers, kneel on opposite sides for two-person CPR, and CPR with heels for a tired rescuer. Devices providing real-time feedback and mobile devices containing CPR applications or software were also found to be beneficial in improving the quality of bystander CPR. However, using mobile devices for improving CPR quality or for assisting DA-CPR might cause rescuers to delay starting CPR.

Conclusions

To further improve the clinical outcomes of victims with cardiac arrest, these effective interventions may be included in the guidelines for bystander CPR.

Real-Time Chest Compression Quality Measurements by Smartphone Camera

Out-of-hospital cardiac arrest (OHCA) is recognized as a global mortality challenge, and digital strategies could contribute to increase the chance of survival. In this paper, we investigate if cardiopulmonary resuscitation (CPR) quality measurement using smartphone video analysis in real-time is feasible for a range of conditions. With the use of a web-connected smartphone application which utilizes the smartphone camera, we detect inactivity and chest compressions and measure chest compression rate with real-time feedback to both the caller who performs chest compressions and over the web to the dispatcher who coaches the caller on chest compressions. The application estimates compression rate with 0.5 s update interval, time to first stable compression rate (TFSCR), active compression time (TC), hands-off time (TWC), average compression rate (ACR), and total number of compressions (NC). Four experiments were performed to test the accuracy of the calculated chest compression rate under different conditions, and a fifth experiment was done to test the accuracy of the CPR summary parameters TFSCR, TC, TWC, ACR, and NC. Average compression rate detection error was 2.7 compressions per minute (±5.0 cpm), the calculated chest compression rate was within ±10 cpm in 98% (±5.5) of the time, and the average error of the summary CPR parameters was 4.5% (±3.6). The results show that real-time chest compression quality measurement by smartphone camera in simulated cardiac arrest is feasible under the conditions tested.

Effects of the Cardio First AngelTM on chest compression performance

BACKGROUND

Survival rates of out-of-hospital cardiac arrest remain poor. Bystander cardiopulmonary resuscitation (CPR) is crucial for survival and feedback devices could improve its quality.

OBJECTIVE

We investigated the quality of chest compression when using the Cardio First AngelTM (CFA) feedback device compared to standard basic life support (BLS). The analysis focused on laymen.

METHODS

Laymen without (n= 43) and with (n= 96) explanation of the device, medical students (n= 128) and medical staff (n= 27) performed 60 seconds of standard versus assisted chest compression using the CFA on a resuscitation manikin. Compression frequency, depth and position were analyzed according to current guidelines.

RESULTS

Laymen showed significantly better success rates regarding correct compression depth when using the CFA (23.3% vs. 55.8%, p= 0.004 and 25.0% vs. 52.1%, p< 0.001, laymen without and with explanation of the device, respectively). Medical students likewise improved (22.7% vs. 42.2%, p= 0.004). Hand positioning was 100% correct in all groups with the device. Improvement in frequency yielded by the CFA was more pronounced for probands with fears of contact (p= 0.02). The benefit of using the device did not differ significantly in laymen with or without explanation.

CONCLUSIONS

Chest compression as performed by laymen was significantly improved with regard to compression depth when using the CFA for guidance and feedback. With the device, no cases of incorrect hand positioning occurred in any group.

Analysis of chest compression depth and rate during cardiopulmonary resuscitation with and without a feedback device

Background:

Many feedback devices have been designed to improve the resuscitation outcomes. None have been implemented as a standard in patient care.

Objectives:

The aim of this study was to evaluate the chest compression depth and rate during cardiopulmonary resuscitation with and without a feedback device and to evaluate differences regarding the impact of a feedback device based on provider experience.

Methods:

The study was performed on 20 men divided into two groups: group A (n = 10)—paramedics; group B (n = 10)—non-paramedics, trained to provide resuscitation. Participants were examined during resuscitation with Ambu Megacode manikin and with or without the feedback device—CPRmeter. Depth of compressions was evaluated in the first and fourth minute of resuscitation with a BTS Smart DX7000 motion capture system. For statistical analysis, summary statistics, Shapiro–Wilk Test of normality, dependent samples t-test, Levene test, t-test for independent samples, or Welch’s t-test were used. Accepted level of significance was α = 0.05.

Results:

Statistically significant greater depth of chest compressions in group A was observed in the first minute of resuscitation with the device versus the first minute without the device. Significant differences in compressions rate between attempts with and without the device were observed in both groups in the first and fourth minute.

Conclusion:

Only the group of paramedics showed in time some benefits of the device related to the depth, whereas for the group of non-paramedics, the device seemed to have even a deleterious effect. The group of paramedics met the 2015 recommendations related to compressions rate all the time, while the non-paramedics only in the fourth minute of the procedure.

Comparison of quality of chest compressions during training of laypersons using Push Heart and Little Anne manikins using blinded CPRcards

BACKGROUND

Mass Cardio-Pulmonary Resuscitation (CPR) training using less expensive and easily portable manikins is one way to increase the number of trained laypeople in a short time. The easy-to-carry, low-cost CPR training model called Push Heart (PH) is widely used in Japan. The aim of this study was to examine if PH can achieve chest compression quality that is similar to that using more conventional Little Anne (LA) manikins for training laypersons.

METHODS

This prospective randomized crossover study was done during routine community CPR training of laypersons in Singapore. The participants were randomly allocated into two groups, using the PH and LA models respectively. They crossed over during the training so that both groups had measurements using both models. Chest compression data were collected using blinded CPRcards, which are credit card-sized devices with accelerometers and data capture. Participants did not receive any CPR feedback during measurement.

RESULTS

Forty-two people had data captured for the study with 15 males. The median compression depth was 41.5 mm on LA and 38.0 mm on PH (p = 0.0664), and median compression rate was 105 cpm on LA and 103 cpm on PH (p = 0.2429). Overall, only 1.5% of compressions performed on the PH achieved adequate depth of between 50-70 mm compared to 5.5% achieved on LA (p = 0.049). In contrast, 84% of all compressions performed on the PH were within the adequate rate of 100-120 cpm compared to 79.5% on LA (p = 0.457). Only the under 20-year-old group was able to achieve adequate median compression depth (50.5 mm) on LA, while the older age groups did not (p = 0.0024). The other age groups performed similar quality of chest compression regardless of the model used. 73.8% of participants preferred the LA for training. After the training, participants felt similarly well-prepared with either model with a median score of 8/10 on LA compared to 7/10 on PH (p = 0.0011).

CONCLUSIONS

The PH can be an alternative mass CPR training model. Both models achieved satisfactory chest compression rates, but the majority of participants, especially the elderly, had difficulty achieving adequate depth.

Improvement of lay rescuer chest compressions with a novel audiovisual feedback device : A randomized trial

BACKGROUND

Bystander actions and skills determine among others the outcome of out-of-hospital cardiac arrest. However, the depth and rate of chest compressions (CC) are difficult to estimate for laypeople and poor CC quality may result. Our study aimed to evaluate the impact of a new feedback device on CC performance by laypeople. The percentage of CC with both correct rate and correct depth of all CC served as primary endpoint.

METHODS

Forty-eight subjects with no medical background performed 2 min of CC on a manikin with and without a novel feedback device (TrueCPR™, Physio-Control, Redmond, Wash.). The device uses a novel, non-accelerometer-based technology. Participants were randomized into two groups. Group 1 performed a 2-min CC trial first with audiovisual feedback followed by a trial with no feedback information, while group 2 performed the task in reverse order.

RESULTS

The absolute percentage of CC with correct rate and depth was significantly higher with the use of the device (59 ± 34% vs. 15 ± 21%, p < 0.0001). The longest interval without correct CC was significantly decreased (76.5 s vs. 27.5 s, p < 0.0001).

CONCLUSION

The quality of CC carried out by laypeople is significantly improved with the use of a new feedback device. The device may be useful for cardiopulmonary resuscitation (CPR) by laypeople and for educational purposes.

Effectiveness of feedback with a smartwatch for high-quality chest compressions during adult cardiac arrest: A randomized controlled simulation study

Previous studies have demonstrated the potential for using smartwatches with a built-in accelerometer as feedback devices for high-quality chest compression during cardiopulmonary resuscitation. However, to the best of our knowledge, no previous study has reported the effects of this feedback on chest compressions in action. A randomized, parallel controlled study of 40 senior medical students was conducted to examine the effect of chest compression feedback via a smartwatch during cardiopulmonary resuscitation of manikins. A feedback application was developed for the smartwatch, in which visual feedback was provided for chest compression depth and rate. Vibrations from smartwatch were used to indicate the chest compression rate. The participants were randomly allocated to the intervention and control groups, and they performed chest compressions on manikins for 2 min continuously with or without feedback, respectively. The proportion of accurate chest compression depth (≥5 cm and ≤6 cm) was assessed as the primary outcome, and the chest compression depth, chest compression rate, and the proportion of complete chest decompression (≤1 cm of residual leaning) were recorded as secondary outcomes. The proportion of accurate chest compression depth in the intervention group was significantly higher than that in the control group (64.6±7.8% versus 43.1±28.3%; p = 0.02). The mean compression depth and rate and the proportion of complete chest decompressions did not differ significantly between the two groups (all p>0.05). Cardiopulmonary resuscitation-related feedback via a smartwatch could provide assistance with respect to the ideal range of chest compression depth, and this can easily be applied to patients with out-of-hospital arrest by rescuers who wear smartwatches.

Assessing practical skills in cardiopulmonary resuscitation: Discrepancy between standard visual evaluation and a mechanical feedback device

This paper aims to analyze agreement in the assessment of external chest compressions (ECC) by 3 human raters and dedicated feedback software.While 54 volunteer health workers (medical transport technicians), trained and experienced in cardiopulmonary resuscitation (CPR), performed a complete sequence of basic CPR maneuvers on a manikin incorporating feedback software (Laerdal PC v 4.2.1 Skill Reporting Software) (L), 3 expert CPR instructors (A, B, and C) visually assessed ECC, evaluating hand placement, compression depth, chest decompression, and rate. We analyzed the concordance among the raters (A, B, and C) and between the raters and L with Cohen's kappa coefficient (K), intraclass correlation coefficients (ICC), Bland-Altman plots, and survival-agreement plots.The agreement (expressed as Cohen's K and ICC) was ≥0.54 in only 3 instances and was ≤0.45 in more than half. Bland-Altman plots showed significant dispersion of the data. The survival-agreement plot showed a high degree of discordance between pairs of raters (A-L, B-L, and C-L) when the level of tolerance was set low.In visual assessment of ECC, there is a significant lack of agreement among accredited raters and significant dispersion and inconsistency in data, bringing into question the reliability and validity of this method of measurement.

Real-time visual feedback during training improves laypersons' CPR quality: a randomized controlled manikin study

OBJECTIVE

The chances of surviving an out-of-hospital cardiac arrest depend on early and high-quality cardiopulmonary resuscitation (CPR). Our aim is to verify whether the use of feedback devices during laypersons' CPR training improves chest compression quality.

METHODS

Laypersons totalling 450 participating in Basic Life Support and Automated External Defibrillation (BLS/AED) courses were randomly divided into three groups: group No Feedback (NF) attended a course without any feedback, group Short Feedback (SF) a course with 1-minute training with real-time visual feedback, and group Long Feedback (LF) a course with 10-minute training with real-time visual feedback. At the end of each course, we recorded 1 minute of compression-only CPR. The primary end point was the difference in the percentage of compressions performed with correct depth.

RESULTS

There was a significant improvement in the percentage of compressions with correct depth in the groups receiving feedback compared to the other (NF v. LF, p=0.022; NF v. SF, p=0.005). This improvement was also present in the percentage of compressions with a complete chest recoil (71.7% in NF, 86.6% in SF, and 88.8% in LF; p<0.001), compressions with the correct hand position (93.2% in NF, 98.2% in SF, and 99.3% in LF; p<0.001), and in the Total CPR Score (79.4% in NF, 90.2% in SF, and 92.5% in LF; p<0.001). There were no significant differences for all of the parameters between group SF and group LF.

CONCLUSIONS

Real-time visual feedback improves laypersons' CPR quality, and we suggest its use in every BLS/AED course for laypersons because it can help achieve the goals emphasized by the International Liaison Committee on Resuscitation recommendations.

Impact of a feedback device on chest compression quality during extended manikin CPR: a randomized crossover study

PURPOSES

Chest compressions require physical effort leading to increased fatigue and rapid degradation in the quality of cardiopulmonary resuscitation overtime. Despite harmful effect of interrupting chest compressions, current guidelines recommend that rescuers switch every 2 minutes. The impact on the quality of chest compressions during extended cardiopulmonary resuscitation has yet to be assessed.

BASIC PROCEDURES

We conducted randomized crossover study on manikin (ResusciAnne; Laerdal). After randomization, 60 professional emergency rescuers performed 2 × 10 minutes of continuous chest compressions with and without a feedback device (CPRmeter). Efficient compression rate (primary outcome) was defined as the frequency target reached along with depth and leaning at the same time (recorded continuously).

MAIN FINDINGS

The 10-minute mean efficient compression rate was significantly better in the feedback group: 42% vs 21% (P< .001). There was no significant difference between the first (43%) and the tenth minute (36%; P= .068) with feedback. Conversely, a significant difference was evident from the second minute without feedback (35% initially vs 27%; P< .001). The efficient compression rate difference with and without feedback was significant every minute, from the second minute onwards. CPRmeter feedback significantly improved chest compression depth from the first minute, leaning from the second minute and rate from the third minute.

PRINCIPAL CONCLUSIONS

A real-time feedback device delivers longer effective, steadier chest compressions over time. An extrapolation of these results from simulation may allow rescuer switches to be carried out beyond the currently recommended 2 minutes when a feedback device is used.

Effect of the Cardio First Angel™ device on CPR indices: a randomized controlled clinical trial

Background

A number of cardiopulmonary resuscitation (CPR) adjunct devices have been developed to improve the consistency and quality of manual chest compressions. We investigated whether a CPR feedback device would improve CPR quality and consistency, as well as patient survival.

Methods

We conducted a randomized controlled study of patients undergoing CPR for cardiac arrest in the mixed medical-surgical intensive care units of four academic teaching hospitals. Patients were randomized to receive either standard manual CPR or CPR using the Cardio First Angel™ CPR feedback device. Recorded variables included guideline adherence, CPR quality, return of spontaneous circulation (ROSC) rates, and CPR-associated morbidity.

Results

A total of 229 subjects were randomized; 149 were excluded; and 80 were included. Patient demographics were similar. Adherence to published CPR guidelines and CPR quality was significantly improved in the intervention group (p < 0.0001), as were ROSC rates (72 % vs. 35 %; p = 0.001). A significant decrease was observed in rib fractures (57 % vs. 85 %; p = 0.02), but not sternum fractures (5 % vs. 17 %; p = 0.15).

Conclusions

Use of the Cardio First Angel™ CPR feedback device improved adherence to published CPR guidelines and CPR quality, and it was associated with increased rates of ROSC. A decrease in rib but not sternum fractures was observed with device use. Further independent prospective validation is warranted to determine if these results are reproducible in other acute care settings.

Trial registration

ClinicalTrials.gov identifier: NCT02394977. Registered on 5 Mar 2015.

A Simulation-based Randomized Controlled Study of Factors Influencing Chest Compression Depth

INTRODUCTION

Current resuscitation guidelines emphasize a systems approach with a strong emphasis on quality cardiopulmonary resuscitation (CPR). Despite the American Heart Association (AHA) emphasis on quality CPR for over 10 years, resuscitation teams do not consistently meet recommended CPR standards. The objective is to assess the impact on chest compression depth of factors including bed height, step stool utilization, position of the rescuer's arms and shoulders relative to the point of chest compression, and rescuer characteristics including height, weight, and gender.

METHODS

Fifty-six eligible subjects, including physician assistant students and first-year emergency medicine residents, were enrolled and randomized to intervention (bed lowered and step stool readily available) and control (bed raised and step stool accessible, but concealed) groups. We instructed all subjects to complete all interventions on a high-fidelity mannequin per AHA guidelines. Secondary end points included subject arm angle, height, weight group, and gender.

RESULTS

Using an intention to treat analysis, the mean compression depths for the intervention and control groups were not significantly different. Subjects positioning their arms at a 90-degree angle relative to the sagittal plane of the mannequin's chest achieved a mean compression depth significantly greater than those compressing at an angle less than 90 degrees. There was a significant correlation between using a step stool and achieving the correct shoulder position. Subject height, weight group, and gender were all independently associated with compression depth.

CONCLUSION

Rescuer arm position relative to the patient's chest and step stool utilization during CPR are modifiable factors facilitating improved chest compression depth.

[Randomised study of the relationship between the use of CPRmeter® device and the quality of chest compressions in a simulated cardiopulmonary resuscitation]

OBJECTIVE

To determine whether the use of CPRmeter(®) during the resuscitation manoeuvres, is related to a higher quality of external cardiac massage, as recommended by the International Liaison Committee on Resuscitation (ILCOR). To compare the quality obtained without the use or this, and whether there are differences related to anthropometric, demographic, professional and/or occupational factors.

METHOD

Experimental, open trial performed with life support simulators in a stratified random sample of 88 health workers randomly distributed between groups A (without indications of the device) and B (with them). The homogeneity of their confounding variables was compared, as well as the compressions depth and compressions rate, the proportion of completed release, and distribution of the quality massage variable (according to criteria ILCOR) between the groups. The qualitative variables were analysed with the chi-square test, and quantitative variables with the Student t-test or Mann-Whitney U-test and the association between the variable quality massage variable, and use of the device with the odds ratio.

RESULTS

Group A: mean depth 42.1mm (standard deviation 10.1), mean rate 121.3/min (21.6), percentage of complete release 71.2% (36.9). Group B: 51.2mm (5.9) 111.9/min (6.4), 92.9% (10.1) respectively. Odds ratio for quality massage regarding the use of the device was 5.170 (95% CI; 2.060-12.977).

CONCLUSIONS

The use of CPRmeter(®) device in simulated resuscitations is related to a higher quality of cardiac massage, improving the approach to the ILCOR recommendations, regardless of the characteristics of the participants. They were 83.8% more likely to achieve a quality massage using the device than without it.

Randomized trial of the chest compressions effectiveness comparing 3 feedback CPR devices and standard basic life support by nurses

BACKGROUND

Out-of-hospital cardiac arrest is a leading cause of mortality and serious neurological morbidity in Europe. We aim to investigate the effect of 3 cardiopulmonary resuscitation (CPR) feedback devices on effectiveness of chest compression during CPR.

METHODS

This was prospective, randomized, crossover, controlled trial. Following a brief didactic session, 140 volunteer nurses inexperienced with feedback CPR devices attempted chest compression on a manikin using 3 CPR feedback devices (TrueCPR, CPR-Ezy, and iCPR) and standard basic life support (BLS) without feedback.

RESULTS

Comparison of standard BLS, TrueCPR, CPR-Ezy, and iCPR showed differences in the effectiveness of chest compression (compressions with correct pressure point, correct depth, and sufficient decompression), which are, respectively, 37.5%, 85.6%, 39.5%, and 33.4%; compression depth (44.6 vs 54.5 vs 45.6 vs 39.6 mm); and compression rate (129.4 vs 110.2 vs 101.5 vs 103.5 min(-1)).

CONCLUSIONS

During the simulated resuscitation scenario, only TrueCPR significantly affected the increased effectiveness compression compared with standard BLS, CPR-Ezy, and iCPR. Further studies are required to confirm the results in clinical practice.

Use of a Metronome in Cardiopulmonary Resuscitation: A Simulation Study

OBJECTIVE

Determine whether the use of a metronome improves chest compression rate and depth during cardiopulmonary resuscitation (CPR) on a pediatric manikin.

METHODS

A prospective, simulation-based, crossover, randomized controlled trial was conducted. Participants included pediatric residents, fellows, nurses, and medical students who were randomly assigned to perform chest compressions on a pediatric manikin with and without an audible metronome. Each participant performed 2 rounds of 2 minutes of chest compressions separated by a 15-minute break.

RESULTS

A total of 155 participants performed 2 rounds of chest compressions (74 with the metronome on during the first round and 81 with the metronome on during the second round of CPR). There was a significant improvement in the mean percentage of compressions delivered within an adequate rate (90-100 compressions per minute) with the metronome on compared with off (72% vs 50%; mean difference [MD] 22%; 95% confidence interval [CI], 15% to 29%). No significant difference was noted in the mean percentage of compressions within acceptable depth (38-51 mm) (72% vs 70%; MD 2%; 95% CI, -2% to 6%). The metronome had a larger effect among medical students (73% vs 55%; MD 18%; 95% CI, 8% to 28%) and pediatric residents and fellows (84% vs 48%; MD 37%; 95% CI, 27% to 46%) but not among pediatric nurses (46% vs 48%; MD -3%; 95% CI, -19% to 14%).

CONCLUSIONS

The rate of chest compressions during CPR can be optimized by the use of a metronome. These findings will help medical professionals comply with the American Heart Association guidelines.

Factors affecting the accuracy of chest compression depth estimation

OBJECTIVE

We aimed to estimate the accuracy of visual estimation of chest compression depth and identify potential factors affecting accuracy.

METHODS

This simulation study used a basic life support mannequin, the Ambu man. We recorded chest compression with 7 different depths from 1 to 7 cm. Each video clip was recorded for a cycle of compression. Three different viewpoints were used to record the video. After filming, 25 clips were randomly selected. Health care providers in an emergency department were asked to estimate the depth of compressions while watching the selected video clips. Examiner determinants such as experience and cardiopulmonary resuscitation training and environment determinants such as the location of the camera (examiner) were collected and analyzed. An estimated depth was considered correct if it was consistent with the one recorded. A multivariate analysis predicting the accuracy of compression depth estimation was performed.

RESULTS

Overall, 103 subjects were enrolled in the study; 42 (40.8%) were physicians, 56 (54.4%) nurses, and 5 (4.8%) emergency medical technicians. The mean accuracy was 0.89 (standard deviation, 0.76). Among examiner determinants, only subjects' occupation and clinical experience showed significant association with outcome (P=0.03 and P=0.08, respectively). All environmental determinants showed significant association with the outcome (all P<0.001). Multivariate analysis showed that accuracy rate was significantly associated with occupation, camera position, and compression depth.

CONCLUSIONS

The accuracy rate of chest compression depth estimation was 0.89 and was significantly related with examiner's occupation, camera view position, and compression depth.