Video-recording and time-motion analyses of manual versus mechanical cardiopulmonary resuscitation during ambulance transport

Evaluation of hospital management of paediatric out-of-hospital cardiac arrest

INTRODUCTION

Pediatric out of hospital cardiac arrest (POHCA) is rare, with high mortality and neurological morbidity. Adherence to Pediatric Advanced Life Support guidelines standardizes in-hospital care and improves outcomes. We hypothesized that in-hospital care of POHCA patients was variable and deviations from guidelines were associated with higher mortality.

METHODS

POHCA patients in the London-Middlesex region between January 2012 and June 2020 were included. The care of children with ongoing arrest (intra-arrest) and post-arrest outcomes were reviewed using the Children's Hospital, London Health Sciences Centre (LHSC) patient database and the Adverse Event Management System.

RESULTS

50 POHCA patients arrived to hospital, with 15 (30%) patients admitted and 2 (4.0%) surviving to discharge, both with poor neurological outcomes and no improvement at 90 days. Deviations occurred at every event with intra-arrest care deviations occurring mostly in medication delivery and defibrillation (98%). Post-arrest deviations occurred mostly in temperature monitoring (60%). Data missingness was 15.9% in the intra-arrest and 1.7% in the post-arrest group.

DISCUSSION

Deviations commonly occurred in both in-hospital arrest and post-arrest care. The study was under-powered to identify associations between DEVs and outcomes. Future work includes addressing specific deviations in intra-arrest and post-arrest care of POHCA patients and standardizing electronic documentation.

A Novel Assessment Using a Panoramic Video Camera of Resuscitation Quality in Patients following Out-of-Hospital Cardiac Arrest

The assessment of cardiopulmonary resuscitation and teamwork quality in prehospital settings has always been challenging. Currently, commercialized quality-monitored chest pads and single-angle cameras are being used to monitor prehospital the resuscitation quality in patients following out-of-hospital cardiac arrest (OHCA). However, both these methods have drawbacks. In New Taipei City, we introduced the panoramic video camera as a novel method to assess the resuscitation quality of OHCA patients to monitor both technical skills and teamwork. The panoramic video camera enabled a comprehensive evaluation of prehospital resuscitation, thereby allowing team members to evaluate their performance by reviewing the video after resuscitation. This is the first step toward improving the evaluation of prehospital resuscitation. Using this panoramic video camera and a high-speed internet connection, real-time resuscitation feedback from the dispatch center or medical directors can be provided promptly, thus, making prehospital resuscitation safe and efficient.

Comparison of prehospital resuscitation quality during scene evacuation and early ambulance transport in out-of-hospital cardiac arrest between residential location and non-residential location

BACKGROUND

High-quality prehospital cardiopulmonary resuscitation (CPR) is important for out-of-hospital cardiac arrest (OHCA). We aimed to evaluate prehospital CPR quality during scene evacuation and early ambulance transport in patients with OHCA according to the type of cardiac arrest location.

METHODS

This retrospective observational cohort study enrolled patients with non-traumatic adult OHCA in Seoul between July 2020 and March 2022. Prehospital CPR quality data extracted from defibrillators were merged with the national OHCA database. The location of cardiac arrest was categorized into two groups (residential and non-residential). CPR quality indices including no-flow (any pause >1.5 s) fraction were compared according to the type of arrest location at each minute of EMS scene evacuation and early ambulance transport (5 min prior to 5 min after ambulance departure).

RESULTS

A total of 1,222 OHCAs were enrolled in the final analysis after serial exclusion. A total of 966 OHCAs (79.1%) occurred in the residential areas. The CPR quality deteriorated during the scene evacuation in both location type. The mean no-flow fractions were significantly higher in residential places than in non-residential places. The mean proportion of adequate compression depth and rate was lower in cardiac arrests in residential places. The discrepancy in EMS CPR quality during scene evacuation was more prominent when mechanical CPR devices were not used.

CONCLUSION

Deterioration of CPR quality was observed just before and during early ambulance transport, especially when the cardiac arrest location was a residential area or when only manual CPR was provided.

Quality of chest compressions during prehospital resuscitation phase from scene arrival to ambulance transport in out-of-hospital cardiac arrest

AIM

Prehospital cardiopulmonary resuscitation is performed from scene arrival to hospital arrival. The diverse prehospital resuscitation phases can affect the quality of chest compressions. This study aimed to evaluate the dynamic changes in chest compression quality during prehospital resuscitation.

METHODS

Adult out-of-hospital cardiac arrest patients treated without prehospital return of spontaneous circulation were included in Seoul between July 2020 and September 2021. The chest compressions quality was assessed using a real-time chest compression feedback device. The prehospital phase was divided by key events during the prehospital resuscitation timeline (phase 1: first 2 min after initiation of chest compression, phase 2: from the end of phase 1 to 1 min prior to ambulance departure; phase 3: from 1 min before to 1 min after ambulance departure; phase 4: from the end of phase 3 to hospital arrival). The main outcome was no-flow fraction. The no-flow fraction between prehospital phases was compared using repeated-measure analysis of variance.

RESULTS

In total, 788 patients were included. Mean no-flow fraction was the highest in phase 3 (phase 1: 11.3% ± 13.8, phase 2: 19.3% ± 12.3, phase 3: 33.0% ± 34.9, phase 4: 18.7% ± 23.7, p < 0.001). The mean number of total no-flow events per minute was also the highest in phase 3. The minute-by-minute analysis showed that the no-flow fraction rapidly increased before ambulance departure and decreased during ambulance transport.

CONCLUSION

Dynamic changes in chest compression quality were observed during prehospital resuscitation phase. The no-flow fraction was the highest from 1 min before to 1 min after ambulance departure.

Predictive performances of ALS and BLS termination of resuscitation rules in out-of-hospital cardiac arrest for different resuscitation protocols

BACKGROUND

Resuscitation guidance has advanced; however, the predictive performance of the termination of resuscitation (TOR) rule has not been validated for different resuscitation protocols published by the American Heart Association (AHA).

METHODS

A retrospective study validating the basic life support (BLS) and advanced life support (ALS) TOR rules was conducted using an Utstein-style database in Tainan city, Taiwan. Adult patients with nontraumatic out-of-hospital cardiac arrests from January 1, 2015, to December 31, 2015, (using the AHA 2010 resuscitation protocol) and from January 1, 2020, to December 31, 2020, (using the AHA 2015 resuscitation protocol) were included. The characteristics of rule performance were calculated, including sensitivity, specificity, positive predictive value (PPV) and negative predictive value.

RESULTS

Among 1260 eligible OHCA patients in 2015, 757 met the BLS TOR rule and 124 met the ALS TOR rule. The specificity and PPV for predicting unfavorable neurological outcomes were 61.1% and 99.0%, respectively, for the BLS TOR rule and 93.8% and 99.2%, respectively, for the ALS TOR rule. A total of 970 OHCA patients were enrolled in 2020, of whom 438 met the BLS TOR rule and 104 met the ALS TOR rule. The specificity and PPV for predicting unfavorable neurological outcomes were 85.7% and 100%, respectively, for the BLS TOR rule and 99.5% and 100%, respectively, for the ALS TOR rule.

CONCLUSIONS

Both the BLS and ALS TOR rules performed better when using the 2015 AHA resuscitation protocols compared to the 2010 protocols, with increased PPVs and decreased false-positive rates in predicting survival to discharge and good neurological outcomes at discharge. The BLS and ALS TOR rules can perform differently while the resuscitation protocols are updated. As the concepts and practices of resuscitation progress, the BLS and ALS TOR rules should be evaluated and validated accordingly.

Efficacy of AutoPulse for Mechanical Chest Compression in Patients with Shock-Resistant Ventricular Fibrillation

INTRODUCTION

Sudden cardiac arrest is one of the most common causes of death. In cases of shock-resistant ventricular fibrillation, immediate transport of patients to the hospital is essential and made possible with use of devices for mechanical chest compression.

OBJECTIVES

The efficacy of AutoPulse in patients with shock-resistant ventricular fibrillation was studied.

METHODS

This is a multicentre observational study on a population of 480,000, with 192 reported cases of out-of-hospital cardiac arrest. The study included patients with shock-resistant ventricular fibrillation defined as cardiac arrest secondary to ventricular fibrillation requiring ≥3 consecutive shocks. Eventually, 18 patients met the study criteria.

RESULTS

The mean duration of resuscitation was 48.4±43 min, 55% of patients were handed over to the laboratory while still in cardiac arrest, 83.3% of them underwent angiography and, in 93.3% of them, infarction was confirmed. Coronary intervention was continued during mechanical resuscitation in 50.0% of patients, 60% of patients survived the procedure, and 27.8% of the patients survived.

CONCLUSIONS

Resistant ventricular fibrillation suggests high likelihood of a coronary component to the cardiac arrest. AutoPulse is helpful in conducting resuscitation, allowing the time to arrival at hospital to be reduced.

The Effect of Athletic Chest Protectors on the Performance of Manual and Mechanical CPR: A Simulation Study

OBJECTIVES

Sudden cardiac arrest is a leading cause of death in athletes. Although athletes wear various athletic chest protectors (ACPs) to prevent commotio cordis (CC), cardiac arrest cases still occur. Although it is established that cardiopulmonary resuscitation (CPR) quality affects outcome, little research has evaluated the effect of ACPs on CPR compressions quality. This study aimed to observe whether: (1) ACPs impact depth, rate, and hand positioning of both bystander and LUCAS CPR. (2) LUCAS devices affect CPR performance compared with traditional compressions.

METHODS

An observational, prospective, convenient sample of 26 emergency medicine residents performed CPR on a high-fidelity Laerdal mannequin, which recorded real-time performance data. Baseline CPR for 1- and 2-minute cycles, CPR on a mannequin wearing the ACP, and ACP removal time was recorded. LUCAS CPR performance was measured at baseline and over the ACP.

RESULTS

Bystander CPR had a statistically significant difference in both hand placement and compression rate for baseline versus ACP compressions (85% vs 57%, P < 0.05; 138 vs 142, P < 0.05, respectively), but not in compression depth (51.08 vs 50.05 mm, P = 0.39). LUCAS CPR had no significant difference in CPR performance. Bystander versus LUCAS CPR had a significant difference in compression rate (138 vs 101, P < 0.01), but not in depth or hand placement.

CONCLUSIONS

Athletic chest protectors significantly impacted hand placement during bystander CPR, which may diminish CPR quality. Considering ACP removal required only 5.4 seconds, removing the ACP before standard CPR may improve quality.

Impact of video-recording on patient outcome and data collection in out-of-hospital cardiac arrests

BACKGROUND

Most research on out-of-hospital resuscitation relies on data collection from medical records. However, the data in medical records are often inaccurate.

OBJECTIVE

To compare the data registration of the medical record with the data from the video recorded resuscitation and study the impact of video recording during resuscitation on the outcome.

METHODS

Out-of-hospital cardiopulmonary resuscitation (CPR) was video recorded using a body-mounted camera. Video recordings were independently reviewed and compared with the data of the medical record. The presence of bystander CPR and witnessed arrest, the initial rhythm, total number of defibrillations, adrenaline dosage and the total duration of CPR were studied. Using the medical records, CPR outcomes were compared for the periods prior to, during and after video recording.

RESULTS

In total, 129 resuscitations were analysed. Of the six parameters, only the number of defibrillations was not significantly different in the medical record compared to the video recordings. The total duration of CPR (69.0%) and the total dose of adrenaline administered (63.6%) were the most incorrectly recorded, followed by the number of defibrillations (34.0%), witnessed arrest (31.0%), bystander CPR (24.0%) and initial rhythm (7%). No statistically significant difference was found comparing the outcomes (ROSC, 24 h and 1 month survival) of the periods before, during and after video recording.

CONCLUSION

We detected a high number of discrepancies between the medical record and the data from the video recorded resuscitation. No significant effect of video-recording on patient outcome was found.

Shoulder strap fixation of LUCAS-2 to facilitate continuous CPR during non-supine (stair) stretcher transport of OHCAs patients

Early recognition and rapid initiation of high-quality cardiopulmonary resuscitation (CPR) are key to maximising chances of achieving successful return of spontaneous circulation in patients with out-of-hospital cardiac arrests (OHCAs), as well as improving patient outcomes both inside and outside hospital. Mechanical chest compression devices such as the LUCAS-2 have been developed to assist rescuers in providing consistent, high-quality compressions, even during transportation. However, providing uninterrupted and effective compressions with LUCAS-2 during transportation down stairwells and in tight spaces in a non-supine position is relatively impossible. In this study, we proposed adaptations to the LUCAS-2 to allow its use during transportation down stairwells and examined its effectiveness in providing high-quality CPR to simulated OHCA patients. 20 volunteer emergency medical technicians were randomised into 10 pairs, each undergoing 2 simulation runs per experimental arm (LUCAS-2 versus control) with a loaded Resusci Anne First Aid full body manikin weighing 60 kg. Quality of CPR compressions performed was measured using the CPRmeter placed on the sternum of the manikin. The respective times taken for each phase of the simulation protocol were recorded. Fisher’s exact tests were used to analyse categorical variables and median test to analyse continuous variables. The LUCAS-2 group required a longer time (~ 35 s) to prepare the patient prior to transport (p < 0.0001) and arrive at the ambulance (p < 0.0001) compared to the control group. The CPR quality in terms of depth and rate for the overall resuscitation period did not differ significantly between the LUCAS-2 group and control group, though there was a reduction in both parameters when evaluating the device’s automated compressions during transport. Nevertheless, the application of the LUCAS-2 device yielded a significantly higher chest compression fraction of 0.76 (p < 0.0001). Our novel adaptations to the LUCAS-2 device allow for uninterrupted compressions in patients being transported down stairwells, thus yielding better chest compression fractions for the overall resuscitation period. Whether potentially improved post-OHCA survival rates may be achieved requires confirmation in a real-world scenario study.

Interaction Effect Between Prehospital Mechanical Chest Compression Device Use and Post-Cardiac Arrest Care on Clinical Outcomes After Out-Of-Hospital Cardiac Arrest

BACKGROUND

Prehospital application of a mechanical chest compression device (MCD) and post-cardiac arrest (PCA) care including coronary reperfusion therapy (CRT) or targeted temperature management (TTM) could affect the clinical outcome in out-of-hospital cardiac arrest (OHCA).

OBJECTIVES

This study aimed to assess whether the effect of PCA care including CRT or TTM differs according to prehospital MCD use in patients with OHCA.

METHODS

Adult OHCA cases with a presumed cardiac etiology and with survival to admission from 2016 to 2017 were enrolled from the Korean nationwide OHCA registry. The main exposures were CRT and TTM during PCA care. The primary outcome was good neurologic recovery defined by a cerebral performance category score of 1 or 2 at hospital discharge. We conducted interaction analyses between MCD use and PCA care including CRT or TTM.

RESULTS

Four thousand three hundred sixty-six OHCA cases were enrolled and 7.9% underwent MCD application. TTM and CRT were performed in 11.2% and 17.9% of the study population. In the interaction analysis, the adjusted odds ratios of TTM and CRT for good neurologic recovery were 2.41 (1.90-3.06) and 3.40 (2.79-4.14) in patients without MCD use and 1.89 (0.97-3.68), and 1.54 (0.79-3.01) in patients with MCD use.

CONCLUSIONS

The effect of PCA care on neurologic outcomes was different according to MCD use in OHCA. The association of good neurologic outcome and PCA care was not observed in the prehospital MCD use group compared with that in the MCD nonuse group.

Automated mechanical cardiopulmonary resuscitation devices versus manual chest compressions in the treatment of cardiac arrest: protocol of a systematic review and meta-analysis comparing machine to human

INTRODUCTION

Cardiac arrest is a leading cause of death in industrialised countries. Cardiopulmonary resuscitation (CPR) guidelines follow the principles of closed chest compression as described for the first time in 1960. Mechanical CPR devices are designed to improve chest compression quality, thus considering the improvement of resuscitation outcomes. This protocol outlines a systematic review and meta-analysis methodology to assess trials investigating the therapeutic effect of automated mechanical CPR devices at the rate of return of spontaneous circulation, neurological state and secondary endpoints (including short-term and long-term survival, injuries and surrogate parameters for CPR quality) in comparison with manual chest compressions in adults with cardiac arrest.

METHODS AND ANALYSIS

A sensitive search strategy will be employed in established bibliographic databases from inception until the date of search, followed by forward and backward reference searching. We will include randomised and quasi-randomised trials in qualitative analysis thus comparing mechanical to manual CPR. Studies reporting survival outcomes will be included in quantitative analysis. Two reviewers will assess independently publications using a predefined data collection form. Standardised tools will be used for data extraction, risks of bias and quality of evidence. If enough studies are identified for meta-analysis, the measures of association will be calculated by dint of bivariate random-effects models. Statistical heterogeneity will be evaluated by I²-statistics and explored through sensitivity analysis. By comprehensive subgroup analysis we intend to identify subpopulations who may benefit from mechanical or manual CPR techniques. The reporting follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

ETHICS AND DISSEMINATION

No ethical approval will be needed because data from previous studies will be retrieved and analysed. Most resuscitation studies are conducted under an emergency exception for informed consent. This publication contains data deriving from a dissertation project. We will disseminate the results through publication in a peer-reviewed journal and at scientific conferences.

PROSPERO REGISTRATION NUMBER

CRD42017051633.

Adult Basic Life Support: International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care Science With Treatment Recommendations on basic life support summarizes evidence evaluations performed for 20 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 3 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

Adult Basic Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This2020 International Consensus on Cardiopulmonary Resuscitation(CPR)and Emergency Cardiovascular Care Science With Treatment Recommendationson basic life support summarizes evidence evaluations performed for 22 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 5 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

Mechanical Chest Compression Device for Out-Of-Hospital Cardiac Arrest: A Nationwide Observational Study

BACKGROUND

There are few studies on the use of a mechanical chest compression (meCC) device during transport in patients with out-of-hospital cardiac arrest (OHCA).

OBJECTIVE

The aim of our study was to compare the performance of an meCC device with that of manual chest compression during transport after OHCA.

METHODS

This study used data from the national cardiac arrest registry of patients with OHCA of presumed cardiac etiology. The primary exposure was the use of an meCC device by an Emergency Medical Services provider while transporting a patient to the emergency department. The primary endpoint was good cerebral performance category at discharge. We compared survival and neurologic outcomes between an meCC device group and a manual chest compression group. We also performed an interaction analysis to assess changes in study outcomes of meCC device use by the initial electrocardiogram (ECG) and transport time interval (TTI).

RESULTS

Among 30,021 adult patients after OHCA with presumed cardiac etiology, an meCC device was used in 2357 (7.6%). After adjustment for possible confounders, there were no significant differences with respect to good neurologic recovery in the outcomes of patients who were treated with an meCC device and those who received manual chest compression (adjusted odds ratio [AOR] 0.66; 95% confidence interval [CI] 0.43-1.02) and survival to discharge (AOR 0.83; 95% CI 0.64-1.06). In the interaction model, the AOR of the meCC device study outcome did not interact with the initial ECG and TTI.

CONCLUSIONS

The meCC device did not show better study outcomes than manual compression.

Manual Versus Mechanical Cardiopulmonary Resuscitation: A Case Against the Machine

Cardiopulmonary resuscitation (CPR) quality, including chest compression rate, depth, and fraction of hands-on time, is integral to cardiac arrest survival. Introducing mechanized devices to target these measures of quality in the challenging prehospital environment holds great promise. Comparing mechanical to manual CPR, animal models deliver favorable results on markers of perfusion and manikin studies demonstrate improved consistency of high-quality CPR performance with device use. Factoring in real-world application with prospective randomized human trials; however, repeatedly fails to show improvements in patient-centered outcomes and thus cannot be supported by current scientific evidence.

Evaluation of the quality of cardiopulmonary resuscitation according to vehicle driving pattern, using a virtual reality ambulance driving system: a prospective, cross-over, randomised study

OBJECTIVES

To analyse changes in the quality of cardiopulmonary resuscitation (CPR) according to driving patterns encountered during ambulance transport, using a virtual reality simulator.

DESIGN

Prospective, cross-over, randomised study.

SETTING

This study was conducted at the National Fire Service Academy, Cheonan-si, Korea.

PARTICIPANTS

Emergency medical technicians (39 men and 9 women) attending the National Fire Service Academy for clinical training with ≥6 months field experience or having performed ≥10 CPR. Individuals who withdrew consent were excluded.

OUTCOME MEASURES

CPR quality parameters (eg, chest compression depth and its variability).

RESULTS

Chest compressions were performed for 8 min each in a stationary and driving state. The mean chest compression depths were 54.8 mm and 55.3 mm during these two states, respectively (p=0.41). The SD of the chest compression depth was significantly higher while in the driving (7.6 mm) than in the stationary state (6.5 mm; p=0.04). The compression depths in the speed bump and sudden stop sections were 51.5 mm and 50.6 mm, respectively, which was shallower than those in all other sections (p<0.001). The correct hand position rate was low in the speed bump, sudden stop and right-hand cornering sections (65.4%, 71.5% and 72.5%, respectively; p=0.001) CONCLUSIONS: Although we found no differences in chest compression quality parameters between the stationary and driving states, the variability in the chest compression depth increased in the driving state. When comparing CPR quality parameters according to driving patterns, we noted a shallower compression depth, increased variability and decreased correct hand position rate in the speed bump, sudden stop and right-hand cornering sections. The clinical significance of these changes in CPR quality during ambulance transport remains to be determined. Future studies on how to reduce changes in the quality of CPR (including research on equipment development) are needed.

Mechanical versus manual chest compressions for cardiac arrest

BACKGROUND

Mechanical chest compression devices have been proposed to improve the effectiveness of cardiopulmonary resuscitation (CPR).

OBJECTIVES

To assess the effectiveness of resuscitation strategies using mechanical chest compressions versus resuscitation strategies using standard manual chest compressions with respect to neurologically intact survival in patients who suffer cardiac arrest.

SEARCH METHODS

On 19 August 2017 we searched the Cochrane Central Register of Controlled Studies (CENTRAL), MEDLINE, Embase, Science Citation Index-Expanded (SCI-EXPANDED) and Conference Proceedings Citation Index-Science databases. Biotechnology and Bioengineering Abstracts and Science Citation abstracts had been searched up to November 2009 for prior versions of this review. We also searched two clinical trials registries for any ongoing trials not captured by our search of databases containing published works: Clinicaltrials.gov (August 2017) and the World Health Organization International Clinical Trials Registry Platform portal (January 2018). We applied no language restrictions. We contacted experts in the field of mechanical chest compression devices and manufacturers.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), cluster-RCTs and quasi-randomised studies comparing mechanical chest compressions versus manual chest compressions during CPR for patients with cardiac arrest.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included five new studies in this update. In total, we included 11 trials in the review, including data from 12,944 adult participants, who suffered either out-of-hospital cardiac arrest (OHCA) or in-hospital cardiac arrest (IHCA). We excluded studies explicitly including patients with cardiac arrest caused by trauma, drowning, hypothermia and toxic substances. These conditions are routinely excluded from cardiac arrest intervention studies because they have a different underlying pathophysiology, require a variety of interventions specific to the underlying condition and are known to have a prognosis different from that of cardiac arrest with no obvious cause. The exclusions were meant to reduce heterogeneity in the population while maintaining generalisability to most patients with sudden cardiac death.The overall quality of evidence for the outcomes of included studies was moderate to low due to considerable risk of bias. Three studies (N = 7587) reported on the designated primary outcome of survival to hospital discharge with good neurologic function (defined as a Cerebral Performance Category (CPC) score of one or two), which had moderate quality evidence. One study showed no difference with mechanical chest compressions (risk ratio (RR) 1.07, 95% confidence interval (CI) 0.82 to 1.39), one study demonstrated equivalence (RR 0.79, 95% CI 0.60 to 1.04), and one study demonstrated reduced survival (RR 0.41, CI 0.21 to 0.79). Two other secondary outcomes, survival to hospital admission (N = 7224) and survival to hospital discharge (N = 8067), also had moderate quality level of evidence. No studies reported a difference in survival to hospital admission. For survival to hospital discharge, two studies showed benefit, four studies showed no difference, and one study showed harm associated with mechanical compressions. No studies demonstrated a difference in adverse events or injury patterns between comparison groups but the quality of data was low. Marked clinical and statistical heterogeneity between studies precluded any pooled estimates of effect.

AUTHORS' CONCLUSIONS

The evidence does not suggest that CPR protocols involving mechanical chest compression devices are superior to conventional therapy involving manual chest compressions only. We conclude on the balance of evidence that mechanical chest compression devices used by trained individuals are a reasonable alternative to manual chest compressions in settings where consistent, high-quality manual chest compressions are not possible or dangerous for the provider (eg, limited rescuers available, prolonged CPR, during hypothermic cardiac arrest, in a moving ambulance, in the angiography suite, during preparation for extracorporeal CPR [ECPR], etc.). Systems choosing to incorporate mechanical chest compression devices should be closely monitored because some data identified in this review suggested harm. Special attention should be paid to minimising time without compressions and delays to defibrillation during device deployment.

Association of the Emergency Medical Services-Related Time Interval with Survival Outcomes of Out-of-Hospital Cardiac Arrest Cases in Four Asian Metropolitan Cities Using the Scoop-and-Run Emergency Medical Services Model

BACKGROUND

Response time interval (RTI) and scene time interval (STI) are key time variables in the out-of-hospital cardiac arrest (OHCA) cases treated and transported via emergency medical services (EMS).

OBJECTIVE

We evaluated distribution and interactive association of RTI and STI with survival outcomes of OHCA in four Asian metropolitan cities.

METHODS

An OHCA cohort from Pan-Asian Resuscitation Outcome Study (PAROS) conducted between January 2009 and December 2011 was analyzed. Adult EMS-treated cardiac arrests with presumed cardiac origin were included. A multivariable logistic regression model with an interaction term was used to evaluate the effect of STI according to different RTI categories on survival outcomes. Risk-adjusted predicted rates of survival outcomes were calculated and compared with observed rate.

RESULTS

A total of 16,974 OHCA cases were analyzed after serial exclusion. Median RTI was 6.0 min (interquartile range [IQR] 5.0-8.0 min) and median STI was 12.0 min (IQR 8.0-16.1). The prolonged STI in the longest RTI group was associated with a lower rate of survival to discharge or of survival 30 days after arrest (adjusted odds ratio [aOR] 0.59; 95% confidence interval [CI] 0.42-0.81), as well as a poorer neurologic outcome (aOR 0.63; 95% CI 0.41-0.97) without an increasing chance of prehospital return of spontaneous circulation (aOR 1.12; 95% CI 0.88-1.45).

CONCLUSIONS

Prolonged STI in OHCA with a delayed response time had a negative association with survival outcomes in four Asian metropolitan cities using the scoop-and-run EMS model. Establishing an optimal STI based on the response time could be considered.

Blood flow maintenance by cardiac massage during cardiopulmonary resuscitation: Classical theories, newer hypotheses, and clinical utility of mechanical devices

The mechanisms by which closed chest cardiac massage produces and maintains blood flow during cardiopulmonary resuscitation are still debated. To date, two main theories exist: the "cardiac pump", which assumes that blood flow is driven by direct cardiac compression and the "chest pump", which hypothesizes that blood flow is caused by changes in intrathoracic pressure. Newer hypotheses including the "atrial pump", the "lung pump", and the "respiratory pump" were also proposed. We reviewed studies supporting these different theories as well as the clinical evidences on the utility of mechanical devices proposed to optimize cardiopulmonary resuscitation, in view of their pathophysiological assumptions with regard to the underlying theory. On the basis of current evidence, a single theory is probably not sufficient to explain how cardiac massage produces blood flow. This suggests that different simultaneous mechanism might be involved. The relative importance of these mechanisms depends on several factors, including delay from collapse to starting of resuscitation, compression force and rate, body habitus, airway pressure, and presenting electrocardiogram. The complexity of the physiologic events occurring during cardiopulmonary resuscitation, together with the need of adequate training for a correct and prompt utilization of mechanical devices, might also partially explain the disappointing results of these devices in most clinical studies.

Effect of Safety Belts on Chest Compression Quality in a Moving Ambulance

Objective

This study aimed to examine the effect of specially designed safety belts on standard cardiopulmonary resuscitation (CPR) quality in a manikin and to determine whether straddle (STR) CPR is equivalent to standard CPR in a moving ambulance.

Methods

Thirty-five emergency medical technicians were recruited and divided into two groups. The first group subjects were randomly assigned to perform standard CPR with or without safety belts. The second group subjects wore safety belts and were randomly assigned to perform STR or standard CPR. Chest compression quality was evaluated by measuring the average rate, depth of compressions, the hands off time and incorrect hand position.

Results

The compression rate was significantly higher in the safety belt group (114.0/min vs. 106.5/min, p=0.001), but the compression depth was not significantly different. The hands-off time was also shorter in the safety belt group (24.5 seconds vs. 40 seconds, p=0.003). When STR CPR was performed, the compression depth was significantly deeper (42 mm vs. 36 mm, p=0.004), and the hands off time was shorter (6 seconds vs. 10 seconds, p=0.039) than with standard CPR. A follow-up questionnaire revealed that 65.7% of the respondents had stopped CPR in the past due to safety reasons, and 48.6% had been injured during CPR.

Conclusions

Wearing belts in a moving ambulance situation can increase the quality of CPR. If an appropriate belt can be designed, the STR method may be used effectively. (Hong Kong j.emerg.med. 2015;22:145-153)

Neurological Favorable Outcomes Associated with EMS Compliance and On-Scene Resuscitation Time Protocol

PURPOSE

Korean national emergency care protocol for EMS providers recommends a minimum of 5 minutes of on-scene resuscitation before transport to hospital in cases of Out-of-Hospital Cardiac Arrest (OHCA). We compared survival outcome of OHCA patients according to scene time interval (STI)-protocol compliance of EMS.

METHODS

EMS treated adult OHCAs with presumed cardiac etiology during a two-year period were analyzed. Non-compliance was defined as hospital transport with STI less than 6 minutes without return of spontaneous circulation (ROSC) on scene. Propensity score for compliance with protocol was calculated and based on the calculated propensity score, 1:1 matching was performed between compliance and non-compliance group. Univariate analysis as well as multivariable logistic model was used to evaluate the effect of compliance to survival outcome.

RESULTS

Among a total of 28,100 OHCAs, EMS transported 7,026 (25.0%) cardiac arrests without ROSC on the scene with an STI less than 6 minutes. A total of 6,854 cases in each group were matched using propensity score matching. Overall survival to discharge rate did not differ in both groups (4.6% for compliance group vs. 4.5 for non-compliance group, p = 0.78). Adjusted odds ratio of compliance for survival to discharge were 1.12 (95% CI 0.92-1.36). More patients with favorable neurological outcome was shown in compliance group (2.5% vs. 1.7%, p < 0.01) and adjusted odds ratio was 1.91 (95% CI 1.42-2.59).

CONCLUSIONS

Although survival to discharge rate did not differ for patient with EMS non-compliance with STI protocol, lesser patients survived with favorable neurological outcomes when EMS did not stay for sufficient time on scene in OHCA before transport.

The Efficacy of LUCAS in Prehospital Cardiac Arrest Scenarios: A Crossover Mannequin Study

Introduction

High-quality cardiopulmonary resuscitation (CPR) is critical for successful cardiac arrest outcomes. Mechanical devices may improve CPR quality. We simulated a prehospital cardiac arrest, including patient transport, and compared the performance of the LUCAS™ device, a mechanical chest compression-decompression system, to manual CPR. We hypothesized that because of the movement involved in transporting the patient, LUCAS would provide chest compressions more consistent with high-quality CPR guidelines.

Methods

We performed a crossover-controlled study in which a recording mannequin was placed on the second floor of a building. An emergency medical services (EMS) crew responded, defibrillated, and provided either manual or LUCAS CPR. The team transported the mannequin through hallways and down stairs to an ambulance and drove to the hospital with CPR in progress. Critical events were manually timed while the mannequin recorded data on compressions.

Results

Twenty-three EMS providers participated. Median time to defibrillation was not different for LUCAS compared to manual CPR (p=0.97). LUCAS had a lower median number of compressions per minute (112/min vs. 125/min; IQR = 102–128 and 102–126 respectively; p<0.002), which was more consistent with current American Heart Association CPR guidelines, and percent adequate compression rate (71% vs. 40%; IQR = 21–93 and 12–88 respectively; p<0.002). In addition, LUCAS had a higher percent adequate depth (52% vs. 36%; IQR = 25–64 and 29–39 respectively; p<0.007) and lower percent total hands-off time (15% vs. 20%; IQR = 10–22 and 15–27 respectively; p<0.005). LUCAS performed no differently than manual CPR in median compression release depth, percent fully released compressions, median time hands off, or percent correct hand position.

Conclusion

In our simulation, LUCAS had a higher rate of adequate compressions and decreased total hands-off time as compared to manual CPR. Chest compression quality may be better when using a mechanical device during patient movement in prehospital cardiac arrest patient.

Non-traumatic out-of-hospital cardiac arrest in rural Taiwan: A retrospective study

OBJECTIVE

Out-of-hospital cardiac arrest (OHCA) studies are usually conducted at metropolitan medical centres. Because rural studies are rare, our study aimed to assess non-traumatic OHCA prevalence and resuscitation outcomes in rural Taiwan.

DESIGN

A retrospective observational study.

SETTING

All seven designated community hospital emergency departments (ED) in Nantou County, Taiwan.

PARTICIPANTS

All OHCA patients from May 2011 to March 2013.

MAIN OUTCOME MEASURES

Any return of spontaneous circulation (ROSC) and survival for ED discharge.

RESULTS

In the 23-month period, 850 OHCA cases were reported; 741 (87.2%) were non-traumatic. The overall ROSC achievement rate was 19.7%, with 16.4% case survival for ED discharge. Logistic regression identified that arrest in public (OR: 2.62, 95% CI: 1.19-5.78), witness when collapsed (OR: 2.14, 95% CI: 1.28-3.60), and cardiopulmonary resuscitation (CPR) by bystander (OR: 2.09, 95% CI: 1.02-4.26) might increase the likelihood of any ROSC; arrest in public (OR: 2.68, 95% CI: 1.10-6.50), witnessed collapse (OR: 2.26, 95% CI: 1.24-4.09) and CPR by bystander (OR: 2.79, 95% CI: 1.28-6.05) might also increase the likelihood of survival. For non-traumatic OHCA patients conveyed to EDs via emergency medical service system (EMS), a shorter response time (OR: 1.09, 95% CI: 1.01-1.18) and travelling time (OR: 1.04, 95% CI: 1.00-1.09) might also increase the chance of survival.

CONCLUSION

Compared to previous data from metropolitan areas, ROSC achievement rate was lower in rural Taiwan. Witness presence, response and travelling times affect ROSC achievement in non-traumatic OHCA patients in rural Taiwan.

Chest compression fraction in ambulance while transporting patients with out-of-hospital cardiac arrest to the hospital in rural Taiwan

INTRODUCTION

Maintaining the standard two-handed chest compression is difficult in high-speed ambulances in rural areas.

METHODS

A retrospective, video-based, observational study was conducted from June to September 2013 in Nantou, a rural county of central Taiwan, to evaluate the chest compression fraction in an ambulance carriage during the travel from the scene to the hospital. The chest compression fraction was calculated as the chest compression time period divided by the ambulance travelling time period; the one-handed and two-handed chest compression fractions were also calculated.

RESULTS

During the 4-month study period, a total of 102 videos that were recorded in an ambulance carriage were reviewed, including 97 cases of manual chest compressions. When there was only one emergency medical technician (EMT) in the carriage, the combined chest compression fraction was 50.6±20.7%; when there were two EMTs, the fraction was 58.3±16.0% and the fraction was 58.3±21.0% in a three-EMT scenario (p=0.221). Moreover, in the carriage, EMTs usually performed one-handed chest compressions.

CONCLUSIONS

The chest compression fraction was low for patients with out-of-hospital cardiac arrest in a moving ambulance, irrespective of the number of providers. Reasons for this observation, as well as the effectiveness of the one-handed chest compression require further evaluation.

Mechanical chest compression devices are associated with poor neurological survival in a statewide registry: A propensity score analysis

OBJECTIVE

To compare functional survival (discharge cerebral performance category 1 or 2) among victims of out-of-hospital cardiac arrest (OHCA) who had resuscitations performed using mechanical chest compression (mech-CC) devices vs. those using manual chest compressions (man-CC).

METHODS

Observational cohort of 2600 cases of OHCA from a statewide, prospectively-collected cardiac arrest registry (Utah Cardiac Arrest Registry to Enhance Survival). Comparison of functional survival among those receiving mech-CC vs man-CC was performed using a mixed-effects Poisson model with inverse probability weighted propensity scores to control for selection bias.

RESULTS

Overall, mech-CC was utilized in 405/2600 (16%) of the total arrests in Utah during this period. 371/405 (92%) were of the load-distributing band type (AutoPulse(®)) and 22/405 (5%) were mechanical piston devices (LUCAS™), while 12/405 (3%) employed other devices. The relative risk (RR) for functional survival comparing mech-CC to man-CC after propensity score adjustment was 0.41 (95% CI 0.24-0.70, p=0.001).

CONCLUSIONS

Mechanical chest compression device use was associated with lower rates of functional survival in this propensity score analysis, controlling for Utstein variables and early return of spontaneous circulation.

Quality between mechanical compression on reducible stretcher versus manual compression on standard stretcher in small elevator

OBJECTIVES

Manual cardiopulmonary resuscitation (CPR) during vertical transport in small elevators using standard stretcher for out-of-hospital cardiac arrest can raise concerns with diminishing quality. Mechanical CPR on a reducible stretcher (RS-CPR) that can be shortened in the length was tested to compare the CPR quality with manual CPR on a standard stretcher (SS-CPR).

METHODS

A randomized crossover manikin simulation was designed. Three teams of emergency medical technicians were recruited to perform serial CPR simulations using two different protocols (RS-CPR and SS-CPR) according to a randomization; the first 6 minutes of manual CPR at the scene was identical for both scenarios and two different protocols during vertical transport in a small elevator followed on a basis of cross-over assignment. The LUCAS-2 Chest Compression System (Zolife AB, Lund, Sweden) was used for RS-CPR. CPR quality was measured using a resuscitation manikin (Resusci Anne QCPR, Laerdal Medical, Stavanger, Norway) in terms of no flow fraction, compression depth, and rate (median and IQR).

RESULTS

A total of 42 simulations were analyzed. CPR quality did not differ significantly at the scene. No flow fraction (%) was significantly lower when the stretcher was moving in RS-CPR then SS-CPR (36.0 (33.8-38.7) vs 44.0 (36.8-54.4), P< .01). RS-CPR showed significantly better quality than SS-CPR; 93.2 (50.6-95.6) vs 14.8 (0-20.8) for adequate depth (P< 0.01), and 97.5 (96.6-98.2) vs 68.9(43.4-78.5) for adequate rate (P< .01).

CONCLUSION

Mechanical CPR on a reducible stretcher during vertical transport showed significant improvement in CPR quality in terms of no-flow fraction, compression depth, and rate compared with manual CPR on a standard stretcher.

Comparison of complications secondary to cardiopulmonary resuscitation between out-of-hospital cardiac arrest and in-hospital cardiac arrest

OBJECTIVE

The aim of this study was to assess whether there was a significant difference in the complications of cardiopulmonary resuscitation (CPR) between out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA) survivors using multidetector computed tomography (MDCT).

SUBJECTS AND METHODS

We performed a retrospective analysis of prospective registry data. We enrolled both OHCA and IHCA patients who underwent successful CPR. We classified chest injuries secondary to chest compression into rib fractures, sternum fractures, and uncommon complications such as lung contusions and extrathoracic complications. We compared these complications according to CPR locations. We also analysed risk factors for CPR complications using multiple regression analysis and classification and regression tree analysis.

RESULTS

During the study period, a total of 148 patients were included in the primary analysis. Rib fractures were detected more in OHCA survivors than in IHCA survivors (74 patients (83.2%) vs. 37 patients (62.7%), p=0.05), and frequency of multiple rib fractures was higher in OHCA survivors than IHCA survivors (69 patients (77.5%) vs. 34 patients (57.6%), p=0.01). Although other complications were not significantly different between the groups, there was a trend for OHCA survivors to sustain more serious and direct high-energy related complications. Older age, longer CPR, and OHCA were significantly associated with incidence of rib fractures, multiple rib fractures, and number of rib fractures.

CONCLUSIONS

Rib fractures were more likely to occur in OHCA survivors, and serious complications tended to occur more often in OHCA compared to IHCA survivors.

Variation of current protocols for managing out-of-hospital cardiac arrest in prehospital settings among Asian countries

BACKGROUND/PURPOSE

Protocols for managing patients with out-of-hospital cardiac arrest (OHCA) may vary due to legal, cultural, or socioeconomic concerns. We sought to assess international variation in policies and protocols related to OHCA.

METHODS

A brief survey was developed by consensus. Elicited information included protocols for managing patients with nontraumatic OHCA or traumatic OHCA, policies for using automated external defibrillators (AEDs) during transportation of patients with ongoing resuscitation, and application of terminations of resuscitation (TOR) rules in prehospital settings in the respondent's city or country. The populations of interest were emergency physicians, medical directors of emergency medical services (EMS), and policy makers.

RESULTS

Responses were obtained from eight cities in six Asian countries. Only one (12.5%) city applied TOR rules for OHCAs. Do-not-resuscitate (DNR) orders were valid in prehospital settings in five (62.5%) cities. All cities used AEDs for nontraumatic OHCAs; seven (87.5%) cities did not routinely use AEDs for traumatic OHCAs. For nontraumatic OHCAs, four (50%) cities performed 2 minutes of on-scene cardiopulmonary resuscitation (CPR) and then transported the patients with ongoing resuscitation to hospitals; three (37.5%) cities performed 4 minutes of on-scene CPR; one (12.5%) city allowed variation in the duration of on-scene CPR.

CONCLUSION

International variation in practices and polices related to OHCAs do exist. Concerns regarding prehospital TOR rules include medical evidence, legal considerations, EMS manpower, public perception, medical oversight, education, EMS characteristics, and cost-effectiveness analysis. Further research is needed to achieve consensus regarding management protocols, especially for EMS that perform resuscitation during transportation of OHCA patients.

Evaluating the Quality of Cardiopulmonary Resuscitation in the Emergency Department by Real-Time Video Recording System

Objectives

To compare cardiopulmonary resuscitation (CPR) quality between manual CPR and miniaturized chest compressor (MCC) CPR. To improve CPR quality through evaluating the quality of our clinical work of resuscitation by real-time video recording system.

Methods

The study was a retrospective observational study of adult patients who experienced CPR at the emergency department of Shanghai Tenth People’s Hospital from March 2013 to August 2014. All the performance of CPR were checked back by the record of “digital real-time video recording system”. Average chest compression rate, actual chest compression rate, the percentage of hands-off period, time lag from patient arrival to chest compression, time lag from patient arrival to manual ventilation, time lag from patient arrival to first IV establish were compared. Causes of chest compression hands-off time were also studied.

Results

112 cases of resuscitation attempts were obtained. Average chest compression rate was over 100 compression per minute (cpm) in the majority of cases. However, indicators such as percentage of hands-off periods, time lag from patient arrival to the first manual ventilation and time lag from patient arrival to the first IV establish seemed to be worse in the manual CPR group compared to MCC CPR group. The saving of operators change time seemed to counteract the time spent on MCC equipment. Indicators such as percentage of hands-off periods, time lag between patient arrival to the first chest compression, time lag between patient arrival to the first manual ventilation and time lag from patient arrival to the first IV establish may influence the survival.

Conclusion

Our CPR quality remained to be improved. MCC may have a potentially positive role in CPR.

Active compression-decompression cardiopulmonary resuscitation (CPR) versus standard CPR for cardiac arrest patients: a meta-analysis

BACKGROUND

Active compression-decompression cardiopulmonary resuscitation (ACDCPR) has been popular in the treatment of patients with cardiac arrest (CA). However, the effect of ACD-CPR versus conventional standard CPR (S-CRP) is contriversial. This study was to analyze the efficacy and safety of ACD-CPR versus S-CRP in treating CA patients.

METHODS

Randomized or quasi-randomized controlled trials published from January 1990 to March 2011 were searched with the phrase "active compression-decompression cardiopulmonary resuscitation and cardiac arrest" in PubMed, EmBASE, and China Biomedical Document Databases. The Cochrane Library was searched for papers of meta-analysis. Restoration of spontaneous circulation (ROSC) rate, survival rate to hospital admission, survival rate at 24 hours, and survival rate to hospital discharge were considered primary outcomes, and complications after CPR were viewed as secondary outcomes. Included studies were critically appraised and estimates of effects were calculated according to the model of fixed or random effects. Inconsistency across the studies was evaluated using the I2 statistic method. Sensitivity analysis was made to determine statistical heterogeneity.

RESULTS

Thirteen studies met the criteria for this meta-analysis. The studies included 396 adult CA patients treated by ACD-CPR and 391 patients by S-CRP. Totally 234 CA patients were found out hospitals, while the other 333 CA patients were in hospitals. Two studies were evaluated with high-quality methodology and the rest 11 studies were of poor quality. ROSC rate, survival rate at 24 hours and survival rate to hospital discharge with favorable neurological function indicated that ACD-CPR is superior to S-CRP, with relative risk (RR) values of 1.39 (95% CI 0.99-1.97), 1.94 (95% CI 1.45-2.59) and 2.80 (95% CI 1.60-5.24). No significant differences were found in survival rate to hospital admission and survival rate to hospital discharge for ACD-CPR versus S-CRP with RR values of 1.06 (95% CI 0.76-1.60) and 1.00 (95% CI 0.73-1.38).

CONCLUSION

Quality controlled studies confirmed the superiority of ACD-CPR to S-CRP in terms of ROSC rate and survival rate at 24 hours. Compared with S-CRP, ACD-CPR could not improve survival rate to hospital admission or survival rate to hospital discharge.

Recommendations on ambulance cardiopulmonary resuscitation in basic life support systems

AIM

Cardiopulmonary resuscitation (CPR) during ambulance transport can be a safety risk for providers and can affect CPR quality. In many Asian countries with basic life support (BLS) systems, patients experiencing out-of-hospital cardiac arrest (OHCA) are routinely transported in ambulances in which CPR is performed. This paper aims to make recommendations on best practices for CPR during ambulance transport in BLS systems.

METHODS

A panel consisting of 20 experts (including 4 North Americans) in emergency medical services (EMS) and resuscitation science was selected, and met over two days. We performed a literature review and selected 33 candidate issues in five core areas. Using Delphi methodology, the issues were classified into dichotomous (yes/no), multiple choice, and ranking questions. Primary consensus between experts was reached when there was more than 70% agreement. Questions with 60-69% agreement were made more specific and were submitted for a second round of voting.

RESULTS

The panel agreed upon 24 consensus statements with more than 70% agreement (2 rounds of voting). The recommendations cover the following: length of time on the scene; advanced airway at the scene; CPR prior to transport; rhythm analysis and defibrillation during transport; prehospital interventions; field termination of resuscitation (TOR); consent for TOR; destination hospital; transport protocol; number of staff members; restraint systems; mechanical CPR; turning off of the engine for rhythm analysis; alternative CPR; and feedback for CPR quality.

CONCLUSION

Recommendations for CPR during ambulance transport were developed using the Delphi method. These recommendations should be validated in clinical settings.

Mechanical versus manual chest compressions for cardiac arrest

BACKGROUND

This is the first update of the Cochrane review on mechanical chest compression devices published in 2011 (Brooks 2011). Mechanical chest compression devices have been proposed to improve the effectiveness of cardiopulmonary resuscitation (CPR).

OBJECTIVES

To assess the effectiveness of mechanical chest compressions versus standard manual chest compressions with respect to neurologically intact survival in patients who suffer cardiac arrest.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Studies (CENTRAL; 2013, Issue 12), MEDLINE Ovid (1946 to 2013 January Week 1), EMBASE (1980 to 2013 January Week 2), Science Citation abstracts (1960 to 18 November 2009), Science Citation Index-Expanded (SCI-EXPANDED) (1970 to 11 January 2013) on Thomson Reuters Web of Science, biotechnology and bioengineering abstracts (1982 to 18 November 2009), conference proceedings Citation Index-Science (CPCI-S) (1990 to 11 January 2013) and clinicaltrials.gov (2 August 2013). We applied no language restrictions. Experts in the field of mechanical chest compression devices and manufacturers were contacted.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), cluster RCTs and quasi-randomised studies comparing mechanical chest compressions versus manual chest compressions during CPR for patients with atraumatic cardiac arrest.

DATA COLLECTION AND ANALYSIS

Two review authors abstracted data independently; disagreement between review authors was resolved by consensus and by a third review author if consensus could not be reached. The methodologies of selected studies were evaluated by a single author for risk of bias. The primary outcome was survival to hospital discharge with good neurological outcome. We planned to use RevMan 5 (Version 5.2. The Nordic Cochrane Centre) and the DerSimonian & Laird method (random-effects model) to provide a pooled estimate for risk ratio (RR) with 95% confidence intervals (95% CIs), if data allowed.

MAIN RESULTS

Two new studies were included in this update. Six trials in total, including data from 1166 participants, were included in the review. The overall quality of included studies was poor, and significant clinical heterogeneity was observed. Only one study (N = 767) reported survival to hospital discharge with good neurological function (defined as a Cerebral Performance Category score of one or two), demonstrating reduced survival with mechanical chest compressions when compared with manual chest compressions (RR 0.41, 95% CI 0.21 to 0.79). Data from four studies demonstrated increased return of spontaneous circulation, and data from two studies demonstrated increased survival to hospital admission with mechanical chest compressions as compared with manual chest compressions, but none of the individual estimates reached statistical significance. Marked clinical heterogeneity between studies precluded any pooled estimates of effect.

AUTHORS' CONCLUSIONS

Evidence from RCTs in humans is insufficient to conclude that mechanical chest compressions during cardiopulmonary resuscitation for cardiac arrest are associated with benefit or harm. Widespread use of mechanical devices for chest compressions during cardiac events is not supported by this review. More RCTs that measure and account for the CPR process in both arms are needed to clarify the potential benefit to be derived from this intervention.

Miniaturized mechanical chest compressor improves calculated cerebral perfusion pressure without compromising intracranial pressure during cardiopulmonary resuscitation in a porcine model of cardiac arrest

OBJECTIVE

One of the major goals of cardiopulmonary resuscitation (CPR) is to provide adequate oxygen delivery to the brain for minimizing cerebral injury resulted from cardiac arrest. The optimal chest compression during CPR should effectively improve brain perfusion without compromising intracranial pressure (ICP). Our previous study has demonstrated that the miniaturized mechanical chest compressor improved hemodynamic efficacy and the success of CPR. In the present study, we investigated the effects of the miniaturized chest compressor (MCC) on calculated cerebral perfusion pressure (CerPP) and ICP.

METHODS

Ventricular fibrillation was electrically induced and untreated for 7min in 13 male domestic pigs weighing 39±3kg. The animals were randomized to receive mechanical chest compression with the MCC (n=7), or the Thumper device (n=6). CPR was performed for 5min before defibrillation attempt by a single 150J shock. At 2.5min of CPR, the epinephrine at a dose of 20μg/kg was administered. Additional epinephrine was administered at an interval of 3min thereafter. If resuscitation was not successful, CPR was resumed for an additional 2min prior to the next defibrillation until successful resuscitation or for a total of 15min. Post-resuscitated animals were observed for 2h.

RESULTS

Significantly greater intrathoracic positive and negative pressures during compression and decompression phases of CPR were observed with the MCC when compared with the Thumper device. The MCC produced significantly greater coronary perfusion pressure and end-tidal carbon dioxide. There were no statistically significant differences in systolic and mean ICP between the two groups; however, both of the measurements were slightly greater in the MCC treated animals. Interestingly, the diastolic ICP was significantly lower in the MCC group, which was closely related to the significantly lower negative intrathoracic pressure in the animals that received the MCC. Most important, systolic, diastolic and mean calculated CerPP were all significantly greater in the animals receiving the MCC.

CONCLUSIONS

In the present study, mechanical chest compression with the MCC significantly improved calculated CerPP but did not compromise ICP during CPR. It may provide a safe and effective chest compression during CPR. Protocol number: P1205.

Association between resuscitation time interval at the scene and neurological outcome after out-of-hospital cardiac arrest in two Asian cities

BACKGROUND AND AIM

It is unclear whether the scene time interval (STI) for cardiopulmonary resuscitation (CPR) is associated with outcomes of out-of-hospital cardiac arrest (OHCA) or not. The present study aimed to determine the association between STI and neurological outcome after OHCA using two large population-based cohorts covering two metropolitan cities in Asia.

METHODS

A retrospective analysis based on two large population-based cohorts from Seoul (2008-2010) and Osaka (2007-2009) was performed for witnessed adult OHCA with presumed cardiac aetiology. The STI, defined as time from wheel arrival at the scene to departure to hospital, was categorised as short (<8min), intermediate (from 8 to <16min) and long (16min or longer) STI on the basis of sensitivity analysis. The primary outcome was good neurological outcome (cerebral performance category 1 or 2). Adjusted odds ratios (AORs) with 95% confidence intervals (CIs) were calculated to determine the association between STIs and outcomes in comparison to the short STI group adjusting for potential risk factors and interaction products.

RESULTS

A total of 7757 patients, 3594 from Seoul and 4163 from Osaka, were finally analysed. There were significant differences among the STI groups for most potential risk variables. Survival to admission was higher in the intermediate STI group (35.7%) than in the short (31.8%) or long STI group (32.6%) (p=0.004). Survival to discharge was not different among groups, at 13.7%, 13.1% and 11.5%, respectively (p=0.094). The intermediate STI group had a significantly better neurological outcome compared with the short STI group (7.7% vs. 4.6%; AOR=1.32; 95% CI, 1.03-1.71), while the long STI (6.6%) did not.

CONCLUSION

Data from two metropolitan cities demonstrated a positive association between intermediate STI from 8 to 16min and good neurological outcome after OHCA.

Mechanical versus manual chest compression CPR under ground ambulance transport conditions

BACKGROUND

Novel mechanical chest compression devices offer the possibility to transport cardiac arrest patients with ongoing CPR and might shorten significantly the time delay to post-resuscitation care.

METHODS

We simulated an eight-minute cardiac resuscitation situation during ambulance transport using CPR training manikins. We compared teams consisting of two experienced resuscitators with the performance of a mechanical chest compression device (LUCAS).

RESULTS

CPR-performance by two experienced resuscitators demonstrated ambivalent results. Whereas mean compression rate was within the recommended range (103/min, 95% CI: 93-113/min), mean compression depth was closely below the actually recommended compression depth of >5 cm (49.7 mm, 95% CI: 46.1-53.3mm). Nevertheless, only a mean of two thirds (67%) of all compressions were classified as manually correct (defined as sternal compression depth >5 cm). In contrast, the LUCAS device showed a constant and reliable CPR performance (99.96% correctly applied chest compressions correctly applied within the device programmed parameters, P = 0.0162) with almost no variance between the different sequences.

CONCLUSION

The LUCAS CPR device represents a reliable alternative to manual CPR in a moving ambulance vehicle during emergency evacuation. Furthermore, it needs less human resources and is safer for the EMS personnel.

Obstacles delaying the prompt deployment of piston-type mechanical cardiopulmonary resuscitation devices during emergency department resuscitation: a video-recording and time-motion study

BACKGROUND

The quality of cardiopulmonary resuscitation (CPR) is important to survival after cardiac arrest. Mechanical devices (MD) provide constant CPR, but their effectiveness may be affected by deployment timeliness.

OBJECTIVES

To identify the timeliness of the overall and of each essential step in the deployment of a piston-type MD during emergency department (ED) resuscitation, and to identify factors associated with delayed MD deployment by video recordings.

METHODS

Between December 2005 and December 2008, video clips from resuscitations with CPR sessions using a MD in the ED were reviewed using time-motion analyses. The overall deployment timeliness and the time spent on each essential step of deployment were measured.

RESULTS

There were 37 CPR recordings that used a MD. Deployment of MD took an average 122.6 ± 57.8s. The 3 most time-consuming steps were: (1) setting the device (57.8 ± 38.3s), (2) positioning the patient (33.4 ± 38.0 s), and (3) positioning the device (14.7 ± 9.5s). Total no flow time was 89.1 ± 41.2s (72.7% of total time) and associated with the 3 most time-consuming steps. There was no difference in the total timeliness, no-flow time, and no-flow ratio between different rescuer numbers, time of day of the resuscitation, or body size of patients.

CONCLUSIONS

Rescuers spent a significant amount of time on MD deployment, leading to long no-flow times. Lack of familiarity with the device and positioning strategy were associated with poor performance. Additional training in device deployment strategies are required to improve the benefits of mechanical CPR.

The effects of a newly developed miniaturized mechanical chest compressor on outcomes of cardiopulmonary resuscitation in a porcine model*

OBJECTIVE

When the duration of cardiac arrest is prolonged, reperfusion of the vital organs by effective chest compression is the most important intervention for successful resuscitation. We investigated the effects of a newly developed miniaturized chest compressor on the outcomes of cardiopulmonary resuscitation.

DESIGN

Prospective, randomized, controlled experimental study.

SETTING

University-affiliated animal research laboratory.

SUBJECTS

Thirty male domestic pigs.

INTERVENTIONS

Ventricular fibrillation was induced in 30 male domestic pigs weighing 35 ± 2 kg. Cardiopulmonary resuscitation was initiated after 7 mins of untreated ventricular fibrillation. The animals were randomized to receive mechanical chest compression with a miniaturized chest compressor, a LUCAS device or a Thumper device. After 5 mins of cardiopulmonary resuscitation, a 150-J defibrillation was delivered. If resuscitation was not successful, cardiopulmonary resuscitation was continued for 2 mins before the next defibrillation. The protocol was continued until successful resuscitation or for a total of 15 mins of cardiopulmonary resuscitation. The animals were observed for 72 hrs after resuscitation.

MEASUREMENTS AND MAIN RESULTS

The miniaturized chest compressor generated significantly greater coronary perfusion pressure, end-tidal PCO2, carotid blood flow, and intrathoracic negative pressure, with significantly lower compression depth and fewer rib fractures when compared with both the LUCAS and Thumper devices. Both the miniaturized chest compressor and LUCAS devices required lower numbers of defibrillation for successful resuscitation when compared with the Thumper device. This was associated with lower prevalence of recurrent ventricular fibrillation and better postresuscitation myocardial and neurological function when compared with the Thumper device.

CONCLUSIONS

The miniaturized chest compressor improves hemodynamic efficacy and the success of cardiopulmonary resuscitation with significantly less injury, which is as effective as the LUCAS device. It may provide a new option for cardiopulmonary resuscitation.

Mechanical CPR devices compared to manual CPR during out-of-hospital cardiac arrest and ambulance transport: a systematic review

Aims

The aim of this paper was to conduct a systematic review of the published literature to address the question: “In pre-hospital adult cardiac arrest (asystole, pulseless electrical activity, pulseless Ventricular Tachycardia and Ventricular Fibrillation), does the use of mechanical Cardio-Pulmonary Resuscitation (CPR) devices compared to manual CPR during Out-of-Hospital Cardiac Arrest and ambulance transport, improve outcomes (e.g. Quality of CPR, Return Of Spontaneous Circulation, Survival)”.

Methods

Databases including PubMed, Cochrane Library (including Cochrane database for systematic reviews and Cochrane Central Register of Controlled Trials), Embase, and AHA EndNote Master Library were systematically searched. Further references were gathered from cross-references from articles and reviews as well as forward search using SCOPUS and Google scholar. The inclusion criteria for this review included manikin and human studies of adult cardiac arrest and anti-arrhythmic agents, peer-review. Excluded were review articles, case series and case reports.

Results

Out of 88 articles identified, only 10 studies met the inclusion criteria for further review. Of these 10 articles, 1 was Level of Evidence (LOE) 1, 4 LOE 2, 3 LOE 3, 0 LOE 4, 2 LOE 5. 4 studies evaluated the quality of CPR in terms of compression adequacy while the remaining six studies evaluated on clinical outcomes in terms of return of spontaneous circulation (ROSC), survival to hospital admission, survival to discharge and Cerebral Performance Categories (CPC). 7 studies were supporting the clinical question, 1 neutral and 2 opposing.

Conclusion

In this review, we found insufficient evidence to support or refute the use of mechanical CPR devices in settings of out-of-hospital cardiac arrest and during ambulance transport. While there is some low quality evidence suggesting that mechanical CPR can improve consistency and reduce interruptions in chest compressions, there is no evidence that mechanical CPR devices improve survival, to the contrary they may worsen neurological outcome.

Delayed high-quality CPR does not improve outcomes

AIM OF STUDY

The quality of cardiopulmonary resuscitation (CPR) is an important factor in the outcome of cardiac arrest. Our objective was to compare outcomes following either immediate low-quality (LQ) CPR or delayed high-quality (HQ) CPR. We hypothesized that delayed HQ CPR will improve the outcomes of CPR in comparison to immediately performing LQ CPR.

METHODS

Eighteen Sprague-Dawley rats were randomized into two groups: (1) Delayed HQ CPR (HQ group, n = 9). (2) Immediate LQ CPR (LQ group, n = 9). Ventricular fibrillation (VF) was induced and untreated for 8 mins. CPR was immediately performed in LQ group for 5 mins. Compression depth was set at 70% of the "optimal compression depth". VF was untreated for an additional 5 mins in HQ group. HQ CPR was started together with ventilation (100% oxygen) and external hypothermia for 8 mins in both groups. The "optimal compression depth" was approximately 30% of the anteroposterior chest diameter. Epinephrine was administrated 3 mins prior to defibrillation attempt. Restoration of spontaneous circulation, postresuscitation myocardial function and survival time were monitored.

RESULTS

All animals in the LQ group and 7 of 9 animals in the HQ group were resuscitated. Myocardial function, including ejection fraction and cardiac output was better in the LQ group than in the HQ group (p < 0.05) and survival time was longer in the LQ group (p < 0.05).

CONCLUSION

The outcomes after immediate LQ CPR, were better than those after delayed HQ CPR in this rat model of cardiac arrest and resuscitation.

Assessment of CPR interruptions from transthoracic impedance during use of the LUCAS™ mechanical chest compression system

BACKGROUND

Quality of cardiopulmonary resuscitation (CPR) is a key determinant of outcome following out-of-hospital cardiac arrest (OHCA). Recent evidence shows manual chest compressions are typically too shallow, interruptions are frequent and prolonged, and incomplete release between compressions is common. Mechanical chest compression systems have been developed as adjuncts for CPR but interruption of CPR during their use is not well documented.

AIM

Analyze interruptions of CPR during application and use of the LUCAS™ chest compression system.

METHODS

54 LUCAS 1 devices operated on compressed air, deployed in 3 major US emergency medical services systems, were used to treat patients with OHCA. Electrocardiogram and transthoracic impedance data from defibrillator/monitors were analyzed to evaluate timing of CPR. Separately, providers estimated their CPR interruption time during application of LUCAS, for comparison to measured application time.

RESULTS

In the 32 cases analyzed, compressions were paused a median of 32.5s (IQR 25-61) to apply LUCAS. Providers' estimates correlated poorly with measured pause length; pauses were often more than twice as long as estimated. The average device compression rate was 104/min (SD 4) and the average compression fraction (percent of time compressions were occurring) during mechanical CPR was 0.88 (SD 0.09).

CONCLUSIONS

Interruptions in chest compressions to apply LUCAS can be <20s but are often much longer, and users do not perceive pause time accurately. Therefore, we recommend better training on application technique, and implementation of systems using impedance data to give users objective feedback on their mechanical chest compression device use.

"Putting it all together" to improve resuscitation quality

Solutions to improve care provided during cardiac arrest resuscitation attempts must be multifaceted and targeted to the diverse number of care providers to be successful. In this article, new approaches to improving cardiac arrest resuscitation performance are reviewed. The focus is on a continuous quality improvement paradigm highlighting improving training methods before actual cardiac arrest events, monitoring quality during resuscitation attempts, and using quantitative debriefing programs after events to educate frontline care providers.

Poor chest compression quality with mechanical compressions in simulated cardiopulmonary resuscitation: a randomized, cross-over manikin study

INTRODUCTION

Mechanical chest compression devices are being implemented as an aid in cardiopulmonary resuscitation (CPR), despite lack of evidence of improved outcome. This manikin study evaluates the CPR-performance of ambulance crews, who had a mechanical chest compression device implemented in their routine clinical practice 8 months previously. The objectives were to evaluate time to first defibrillation, no-flow time, and estimate the quality of compressions.

METHODS

The performance of 21 ambulance crews (ambulance nurse and emergency medical technician) with the authorization to perform advanced life support was studied in an experimental, randomized cross-over study in a manikin setup. Each crew performed two identical CPR scenarios, with and without the aid of the mechanical compression device LUCAS. A computerized manikin was used for data sampling.

RESULTS

There were no substantial differences in time to first defibrillation or no-flow time until first defibrillation. However, the fraction of adequate compressions in relation to total compressions was remarkably low in LUCAS-CPR (58%) compared to manual CPR (88%) (95% confidence interval for the difference: 13-50%). Only 12 out of the 21 ambulance crews (57%) applied the mandatory stabilization strap on the LUCAS device.

CONCLUSIONS

The use of a mechanical compression aid was not associated with substantial differences in time to first defibrillation or no-flow time in the early phase of CPR. However, constant but poor chest compressions due to failure in recognizing and correcting a malposition of the device may counteract a potential benefit of mechanical chest compressions.