Use Of Mechanical Cardiopulmonary Resuscitation Research Articles

Characteristics and outcomes of out-of-hospital cardiac arrest in a hilly area: Utstein Registry data from the Nagasaki Medical Region, Japan.

To analyze characteristics and investigate prognostic indicators of out-of-hospital cardiac arrest (OHCA) in a hilly area in Japan. A retrospective population-based study was conducted using the Utstein Registry for 4280 OHCA patients in the Nagasaki Medical Region (NMR) registered over the 10-year period from 2011 to 2020. The main outcome measure was a favorable cerebral performance category (CPC 1-2). Sites at which OHCA occurred were classified into "sloped places (SPs)" (not easily accessible by emergency medical services [EMS] personnel due to slopes) and "accessible places (APs)" (EMS personnel could park an ambulance close to the site). The characteristics and prognosis based on CPC were compared between SPs and APs, and multivariable analysis was performed. No significant improvement in prognosis occurred in the NMR from 2011 to 2020. Prognosis in SPs was significantly worse than that in APs. However, multivariable analysis did not identify SP as a prognostic indicator. The following factors were associated with survival and CPC 1-2: age group, witness status, first documented rhythm, bystander-initiated cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use, use of mechanical CPR (m-CPR) device or esophageal obturator airway (EOA), and year. Both m-CPR and EOA use were associated with a poor prognosis. In a hilly area, OHCA patients in SPs had a worse prognosis than those in APs, but SPs was not significantly associated with prognosis by multivariable analysis. Interventions to increase bystander-initiated CPR and AED use could potentially improve outcomes of OHCA in the NMR.

Objective performance of emergency medical technicians in the use of mechanical cardiopulmonary resuscitation compared with subjective self-evaluation: a cross-sectional, simulation-based study

ObjectiveTo evaluate the subjective and objective resuscitation performance of emergency medical technicians (EMTs) using mechanical cardiopulmonary resuscitation (MCPR) devices.Design and settingThis was a cross-sectional simulation-based study where participants installed the...

Comparison between Prehospital Mechanical Cardiopulmonary Resuscitation (CPR) Devices and Manual CPR for Out-of-Hospital Cardiac Arrest: A Systematic Review, Meta-Analysis, and Trial Sequential Analysis.

In pre-hospital settings, efficient cardiopulmonary resuscitation (CPR) is challenging; therefore, the application of mechanical CPR devices continues to increase. However, the evidence of the benefits of using mechanical CPR devices in pre-hospital settings for adult out-of-hospital cardiac arrest (OHCA) is controversial. This meta-analysis compared the effects of mechanical and manual CPR applied in the pre-hospital stage on clinical outcomes after OHCA. Cochrane Library, PubMed, Embase, and ClinicalTrials.gov were searched from inception until October 2021. Studies comparing mechanical and manual CPR applied in the pre-hospital stage for survival outcomes of adult OHCA were eligible. Data abstraction, quality assessment, meta-analysis, trial sequential analysis (TSA), and grading of recommendations, assessment, development, and evaluation were conducted. Seven randomized controlled and 15 observational studies were included. Compared to manual CPR, pre-hospital use of mechanical CPR showed a positive effect in achieving return of spontaneous circulation (ROSC) and survival to admission. No difference was found in survival to discharge and discharge with favorable neurological status, with inconclusive results in TSA. In conclusion, pre-hospital use of mechanical CPR devices may benefit adult OHCA in achieving ROSC and survival to admission. With low certainty of evidence, more well-designed large-scale randomized controlled trials are needed to validate these findings.

Abstract 12097: The Impact of a High-Performance Cardiopulmonary Resuscitation Protocol on Survival From Out-of-Hospital Cardiac Arrests Witnessed by Paramedics

Introduction: Some emergency medical services (EMS) have shown increases in survival from out-of-hospital cardiac arrest (OHCA) following the implementation of a high-performance cardiopulmonary resuscitation (CPR) protocol. Despite this, little is known about the effect of high-performance CPR on OHCA witnessed by EMS personnel. Methods: We performed a retrospective cohort study of adult, EMS-witnessed OHCA patients of medical etiology from a population-based registry in Victoria, Australia. Patients treated after the introduction of a high-performance CPR protocol and training program between February 2019 and January 2020 were compared to historical controls between January 2015 and January 2019. The effect of the intervention on survival to hospital discharge was examined using logistic regression models adjusted for temporal and arrest factors. Results: A total of 1,561 and 420 EMS-witnessed OHCA patients were treated in the control and intervention periods, respectively. Baseline characteristics were similar across control and intervention periods, including the median age of cases (69 vs. 69 years, p=0.97), male sex (65.2% vs. 60.5%, p=0.08) and initial shockable arrests (33.7% vs. 29.3%, p=0.09). Resuscitation interventions were similar across groups, except for the use of mechanical CPR which declined during the intervention period (17.0% vs. 10.7%, p<0.001). Unadjusted survival to hospital discharge was similar across control and intervention periods for the overall population (29.4% vs. 32.1%, p=0.27), but significantly higher during the intervention period for initial shockable arrests (66.6% vs. 76.9%, p=0.03). After adjustment for confounders, cases in the intervention period were associated with a 43% increase (adjusted odds ratio [AOR] 1.43; 95% CI: 1.05, 1.94; p=0.02) in the risk-adjusted odds of survival to hospital discharge or a 79% increase (AOR 1.79, 95% CI: 1.09, 2.95; p=0.02) for initial shockable arrests. Conclusions: The implementation of a high-performance CPR quality improvement intervention was associated with significant improvement in survival from EMS witnessed OHCA. Efforts to monitor and improve CPR performance could yield further improvements in patient outcomes.

Comparison of different resuscitation methods with regard to injury patterns in cardiac arrest survivors based on computer tomography

PurposeTo ensure that patients survive cardiac arrest, cardiopulmonary resuscitation (CPR) is needed. However, the procedure itself can lead to severe injuries. This study aims to examine both possibilities of resuscitation - mechanical or manual - with regard to their risk of injury. To this end, we compare the injuries patterns in both groups of patients after successful resuscitation based on computer tomography (CT). MethodsThis single-centre retrospective study included 32 patients (female: 21.87 %, male: 78.12 %, Mean age: 60.22 ± 13.93 years) with cardiac arrest followed by successful mechanical CPR, who underwent an early whole-body CT. A control group of 32 patients (female: 21.87 %, male: 78.12 %, mean age: 60.75 ± 13.34 years) that had been resuscitated successfully with manual CPR was matched according to gender and age for a better statistical comparison. Patients with cardiac arrest due to trauma were excluded from the study population. ResultsMechanically resuscitated patients showed significantly more CPR-related injuries than those who were resuscitated manually (100 % vs. 84.37 %; p = 0.02). In particular, dislocated rib fractures (40.47 vs. 23.80 mean rank, p < 0.01), sternal fractures (74.19 % vs. 25 %; p < 0,01), bleeding complications (29.03 % vs. 3.12 %; p = 0.01), pneumothorax (38.71 % vs. 9.37 %; p = 0.01), mediastinal haematomas (58.01 % vs. 25 %, p = 0.01) and liver lacerations (29.03 % vs. 0 %, p = 0.04) were observed significantly more in patients after mechanical CPR compared to those with manual resuscitation. ConclusionsThe guideline-based use of mechanical CPR results in a significant increase of internal and musculoskeletal injuries compared to manual CPR.

Use of Mechanical Cardiopulmonary Resuscitation Devices for Out-of-Hospital Cardiac Arrest, 2010-2016

Out-of-hospital cardiac arrest is a common scenario facing prehospital emergency medical services (EMS) professionals and nearly always involves either manual or mechanical cardiopulmonary resuscitation (CPR). Mechanical CPR devices are expensive and prior clinical trials have not provided evidence of benefit for patients when compared with manual CPR. To investigate the use of mechanical CPR in the prehospital setting and determine whether patient demographic characteristics or geographical location is associated with its use. A retrospective cross-sectional study was performed using the 2010 through 2016 National Emergency Medical Services Information System data. Participants included all patients identified by EMS professionals as having out-of-hospital cardiac arrest. Use of CPR, categorized as manual or mechanical. From 2010 to 2016, 892 022 patients (38.6% female, 60.4% male, missing for 1%; mean [SD] age, 61.1 [20.5] years) with out-of-hospital cardiac arrest were identified by EMS professionals. Overall, manual CPR was used for 618 171 patients (69.3%) and mechanical CPR was used for 45 493 patients (5.1%). The risk-standardized rate of mechanical CPR use, accounting for patient demographic and geographical characteristics, rose from 1.9% in 2010 to 8.0% in 2016 (P < .001). In multivariable analyses, use of mechanical CPR devices was increasingly likely over time among patients identified with out-of-hospital cardiac arrest treated by EMS professionals, increasing from an adjusted odds ratio of 1.58 (95% CI, 1.42-1.77; P < .001) when comparing 2011 with 2010, to an adjusted odds ratio of 11.32 (95% CI, 10.22-12.54; P < .001) when comparing 2016 with 2010. In addition, several other patient demographic and geographical characteristics were associated with a higher likelihood of receiving mechanical CPR, including being 65 years or older, being male, being Hispanic, as well as receiving treatment in the Northeast Census Region, in a suburban location, or in a zip code with a median annual income greater than $20 000. Mechanical CPR device use increased more than 4-fold among patients with out-of-hospital cardiac arrest treated by EMS professionals. Given the high costs of mechanical CPR devices, better evidence is needed to determine whether these devices improve clinically meaningful outcomes for patients treated for out-of-hospital cardiac arrest by prehospital EMS professionals to justify the significant increase in their use.

Confirming the Clinical Safety and Feasibility of a Bundled Methodology to Improve Cardiopulmonary Resuscitation Involving a Head-Up/Torso-Up Chest Compression Technique.

Objectives:Combined with devices that enhance venous return out of the brain and into the thorax, preclinical outcomes are improved significantly using a synergistic bundled approach involving mild elevation of the head and chest during cardiopulmonary resuscitation. The objective here was to confirm clinical safety/feasibility of this bundled approach including use of mechanical cardiopulmonary resuscitation provided at a head-up angle.Design:Quarterly tracking of the frequency of successful resuscitation before, during, and after the clinical introduction of a bundled head-up/torso-up cardiopulmonary resuscitation strategy.Setting:9-1-1 response system for a culturally diverse, geographically expansive, populous jurisdiction.Patients:All 2,322 consecutive out-of-hospital cardiac arrest cases (all presenting cardiac rhythms) were followed over 3.5 years (January 1, 2014, to June 30, 2017).Interventions:In 2014, 9-1-1 crews used LUCAS (Physio-Control Corporation, Redmond, WA) mechanical cardiopulmonary resuscitation and impedance threshold devices for out-of-hospital cardiac arrest. After April 2015, they also 1) applied oxygen but deferred positive pressure ventilation several minutes, 2) solidified a pit-crew approach for rapid LUCAS placement, and 3) subsequently placed the patient in a reverse Trendelenburg position (~20°).Measurements and Main Results:No problems were observed with head-up/torso-up positioning (n = 1,489), but resuscitation rates rose significantly during the transition period (April to June 2015) with an ensuing sustained doubling of those rates over the next 2 years (mean, 34.22%; range, 29.76–39.42%; n = 1,356 vs 17.87%; range, 14.81–20.13%, for 806 patients treated prior to the transition; p < 0.0001). Outcomes improved across all subgroups. Response intervals, clinical presentations and indications for attempting resuscitation remained unchanged. Resuscitation rates in 2015–2017 remained proportional to neurologically intact survival (~35–40%) wherever tracked.Conclusions:The head-up/torso-up cardiopulmonary resuscitation bundle was feasible and associated with an immediate, steady rise in resuscitation rates during implementation followed by a sustained doubling of the number of out-of-hospital cardiac arrest patients being resuscitated. These findings make a compelling case that this bundled technique will improve out-of-hospital cardiac arrest outcomes significantly in other clinical evaluations.

Does use of the LUCAS device improve mortality in adult patients with out-of-hospital cardiac arrest?

Out-of-hospital cardiac arrest (OHCA) is a common occurrence in the UK, with 60,000 cases reported annually. To improve outcomes among these patients it is necessary to improve links in the cardiac arrest chain of survival. Cardiopulmonary resuscitation (CPR) is one of the main elements of this chain because it reduces further ischaemic insult in the brain and heart by contributing to blood flow. However, even the best manual CPR provides only 20%-30% of the normal cardiac output. Despite the emphasis on timely CPR at the correct rate and depth, delivery of compressions is suboptimal for many patients and mechanical devices may improve outcomes. This article critically appraises two important papers on the use of mechanical CPR for OHCA. It also suggests potential uses for this treatment option and areas for future research.

An insidious and deadly complication of mechanical chest compressions in a patient on anticoagulation and the subtle echocardiographic findings that enabled timely diagnosis

Good-quality chest compressions improve outcomes in cardiac arrest. While manual chest compressions are suboptimal in this regard, the LUCAS device has been shown to improve the effectiveness of chest compressions during cardiopulmonary resuscitation (CPR). The complication rate associated with mechanical CPR, however, has not been adequately studied. Limited evidence suggests no difference in internal injury between manual and mechanical CPR. We report the case of a patient on anticoagulation who developed a mediastinal hematoma post mechanical CPR and on whom subtle findings on initial echocardiography could have alerted the clinician to this complication early during the clinical course. This case further suggests that there may be special populations of patients in whom we may need to be more vigilant in the use of mechanical CPR.

Prompt use of mechanical cardiopulmonary resuscitation in out-of-hospital cardiac arrest: the MECCA study report.

Early use of mechanical cardiopulmonary resuscitation (CPR) for out-of-hospital cardiac arrest (OHCA) may improve survival outcomes. Current evidence for such devices uses outcomes from an intention-to-treat (ITT) perspective. We aimed to determine whether early use of mechanical CPR using a LUCAS 2 device results in better outcomes. A prospective, randomised, multicentre study was conducted over one year with LUCAS 2 devices in 14 ambulances and manual CPR in 32 ambulances to manage OHCA. The primary outcome was return of spontaneous circulation (ROSC). Secondary outcomes were survival at 24 hours, discharge from hospital and 30 days. Of the 1,274 patients recruited, 1,191 were eligible for analysis. 889 had manual CPR and 302 had LUCAS CPR. From an ITT perspective, outcomes for manual and LUCAS CPR were: ROSC 29.2% and 31.1% (odds ratio [OR] 1.09, 95% confidence interval [CI] 0.82-1.45; p = 0.537); 24-hour survival 11.2% and 13.2% (OR 1.20, 95% CI 0.81-1.78; p = 0.352); survival to discharge 3.6% and 4.3% (OR 1.20, 95% CI 0.62-2.33; p = 0.579); and 30-day survival 3.0% and 4.0% (OR 1.32, 95% CI 0.66-2.64; p = 0.430), respectively. By as-treated analysis, outcomes for manual, early LUCAS and late LUCAS CPR were: ROSC 28.0%, 36.9% and 24.5%; 24-hour survival 10.6%, 15.5% and 8.2%; survival to discharge 2.9%, 5.8% and 2.0%; and 30-day survival 2.4%, 5.8% and 0.0%, respectively. Adjusted OR for survival with early LUCAS vs. manual CPR was 1.47 after adjustment for other variables (p = 0.026). This study showed a survival benefit with LUCAS CPR as compared to manual CPR only, when the device was applied early on-site.

Continuous Quality Improvement Efforts Increase Survival with Favorable Neurologic Outcome after Out-of-hospital Cardiac Arrest

Objective: To assess system-wide implementation of specific therapies focused on perfusion during cardiopulmonary resuscitation (CPR) and cerebral recovery after Return of Spontaneous Circulation (ROSC). Methods: Before and after retrospective analysis of an out-of-hospital cardiac arrest database. Implementation trial in the urban/suburban community of Alameda County, California, USA, population 1.6 million, from November 2009–December 2012. Adult patients with non-traumatic out-of-hospital cardiac arrest (OHCA) who received CPR and/or defibrillation. The impedance threshold device was used throughout this study and there was an increased use of mechanical CPR (mCPR) and in-hospital therapeutic hypothermia (HTH). Results: Rates of ROSC, survival to hospital discharge and Cerebral Performance Category (CPC) scores were compared using univariate and multivariable analyses. A total of 2,926 adult non-traumatic patients with OHCA received CPR during the study period. From 2009–2011 to 2012, there was an increase in ROSC from 29.0% to 34.4% (p = 0.003) and a non-significant increase in hospital discharge from 10.2% to 12.0% (p = 0.16). There was a 76% relative increase in survival with favorable neurologic function between the two periods, as determined by CPC ≤ 2, from 4.5% to 7.9% (unadjusted OR = 1.80; CI = 1.31, 2.48; p < 0.001). After adjusting for witnessed arrest, bystander CPR, initial rhythm (VT/VF vs. others), placement of an advanced airway, EMS response time, drugs administered, and age, the OR was 1.61 (1.10, 2.36; p = 0.015). Using a stepwise multivariable logistic regression model, the independent predictors of CPC ≤ 2 were 2012 (vs. 2009–2011; p = 0.022), witnessed arrest (p < 0.001), initial rhythm VT/VF (p < 0.001), and advanced airway (inverse association p < 0.001). Additional analyses of the three prescribed therapies, separately and in combination, demonstrated that for those patients admitted to the hospital, mCPR with HTH had the biggest impact on survival to hospital discharge with CPC ≤ 2. Conclusions: Specific therapies within a system of care (mCPR, HTH), developed to enhance circulation during CPR and cerebral recovery after ROSC, significantly improved survival by 74% with favorable neurologic function following OHCA.

Making sense of clinical outcomes following cardiac arrest.

To provide a summary of the recent literature on clinical outcomes in adults with cardiac arrest, focusing on the impact of patient-specific factors in combination with cardio-pulmonary resuscitation (CPR) related, and postresuscitative-related factors. Cardiac arrest is a major cause of morbidity and mortality worldwide. Despite the use of conventional cardiopulmonary resuscitation, rates of return of spontaneous circulation and survival with minimal neurologic impairment remain low. A number of recent studies have examined the impact of patient-specific factors (duration of cardiac arrest, initial rhythm, age, premorbid states), CPR-related (the use of mechanical CPR, the use of impedance threshold device, vasopressors, extra-corporeal membrane oxygenation, active compression-decompression, and impedance threshold device), and postresuscitative-related factors (hypothermia, coronary angiography, hyperoxia, hyper/hypocapnia, mean arterial blood pressure) on cardiac arrest outcomes. Further studies, namely randomized controlled trials, assessing the impact of advanced therapies are warranted to evaluate their impact on survival and neurologic function in adults with cardiac arrest.

The combined use of mechanical CPR and a carry sheet to maintain quality resuscitation in out-of-hospital cardiac arrest patients during extrication and transport

BackgroundQuality of manual cardiopulmonary resuscitation (CPR) during extrication and transport of out-of-hospital cardiac arrest victims is known to be poor. Performing manual CPR during ambulance transport poses significant risk to the attending emergency medical services crew. We sought to use pre-hospital video recording to objectively analyse the impact of introducing mechanical CPR with an extrication sheet (Autopulse, Zoll) to an advanced, second-tier cardiac arrest response team. MethodsThe study was conducted prospectively using defibrillator downloads and analysis of pre-hospital video recording to measure the quality of CPR during extrication from scene and ambulance transport of the OHCA patient. Adult patients with non-traumatic OHCA were included. The interruption to manual CPR to during extrication and to deploy the mechanical CPR device was analysed. ResultsIn the manual CPR group, 53 OHCA cases were analysed for quality of CPR during extrication. The median time that chest compression was interrupted to allow the patient to be carried from scene to the ambulance was 270s (IQR 201–387s). 119 mechanical CPR cases were analysed. The median time interruption from last manual compression to first Autopulse compression was 39s (IQR 29–47s). The range from last manual compression to first Autopulse compression was 14–118s. ConclusionMechanical CPR used in combination with an extrication sheet can be effectively used to improve the quality of resuscitation during extrication and ambulance transport of the refractory OHCA patient. The time interval to deploy the mechanical CPR device can be shortened with regular simulation training.

The importance of cardiopulmonary resuscitation quality

Cardiopulmonary resuscitation (CPR) is a fundamental component of initial care for the victim of cardiac arrest. In the past few years, increasing quantitative evidence has demonstrated that survival from cardiac arrest is dependent on the quality of delivered CPR. This review will focus on this body of evidence and on a range of practical approaches to improving CPR performance. A number of strategies to improve CPR quality have been evaluated recently, during both prehospital and in-hospital cardiac arrest care. These strategies have included the use of real-time CPR sensing and feedback, the employment of physiologic monitoring such as end-tidal CO(2) measurement and the use of metronome prompting. The use of mechanical CPR devices to avoid the challenges of manual CPR performance has also represented a topic of great current interest. Additional approaches have focused on both prearrest training (e.g. high-fidelity simulation education and CPR refreshers) and postarrest training (e.g. debriefing). A number of strategies have been evaluated to improve CPR performance. While many questions remain surrounding the relative value of each approach, it is likely that combinations of these methods may be useful in a variety of care settings to improve care for cardiac arrest victims.

Load-distributing band improves ventilation and hemodynamics during resuscitation in a porcine model of prolonged cardiac arrest

BackgroundThe use of mechanical cardiopulmonary resuscitation (CPR) has great potential for the clinical setting. The purpose of present study is to compare the hemodynamics and ventilation during and after the load-distributing band CPR, versus the manual CPR in a porcine model of prolonged cardiac arrest, and to investigate the influence of rescue breathing in different CPR protocols.MethodsSixty-four male pigs (n = 16/group), weighing 30 ± 2 kg, were induced ventricular fibrillation and randomized into four resuscitation groups: continuous load-distributing band CPR without rescue ventilation (C-CPR), load-distributing band 30:2 CPR (A-CPR), load-distributing band CPR with continuous rescue breathing (10/min) (V-CPR) or manual 30:2 CPR (M-CPR). Respiratory variables and hemodynamics were recorded continuously; blood gas was analyzed.ResultsTidal volume produced by compressions in the A-, C- and V-CPR groups were significantly higher compared with the M-CPR group (all p < 0.05). Coronary perfusion pressure of the V-CPR group was significantly lower than the C-CPR group (p < 0.01), but higher than the M-CPR group. The increasing of lung dead space after restoration of spontaneous circulation was significantly greater in the M-CPR group compared with the A-, C- and V-CPR groups (p < 0.01). Blood pH gradually decreased and was lower in the M-CPR group than that in the A-, C- and V-CPR groups (p < 0.01). PaO2 of the A-, C- and V-CPR groups were significantly higher and PaCO2 were significantly lower compared with the M-CPR (both p < 0.05). Cerebral performance categories were better in the A-, C- and V-CPR groups compared with the M-CPR group (p < 0.0001).ConclusionsThe load-distributing band CPR significantly improved respiratory parameters during resuscitation by augmenting passive ventilation, and significantly improved coronary perfusion pressure. The volume of ventilation produced by the load-distributing band CPR was adequate to maintain sufficient gas exchange independent of rescue breathing.

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

AimsThe 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)”.MethodsDatabases 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.ResultsOut 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.ConclusionIn 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.