Mechanical versus manual chest compressions for cardiac arrest

Suction cup on a piston-based chest compression device improves coronary perfusion pressure and cerebral oxygenation during experimental cardiopulmonary resuscitation

Introduction

The presented study aimed to investigate whether a mechanical chest compression piston device with a suction cup assisting chest recoil could impact the hemodynamic status when compared to a bare piston during cardiopulmonary resuscitation.

Methods

16 piglets were anesthetized and randomized into 2 groups. After 3 minutes of induced ventricular fibrillation, a LUCAS 3 device was used to perform chest compressions, in one group a suction cup was mounted on the device’s piston, while in the other group, compressions were performed by the bare piston. The device was used in 30:2 mode and the animals were manually ventilated. Endpoints of the study were: end tidal carbon dioxide, coronary and cerebral perfusion pressures, and brain oxygenation (measured using near infrared spectroscopy). At the end of the protocol, the animals that got a return to spontaneous circulation were observed for 60 minutes, then euthanized.

Results

No difference was found in end tidal carbon dioxide or tidal volumes. Coronary perfusion pressure and cerebral oxygenation were higher in the Suction cup group over the entire experiment time, while cerebral perfusion pressure was higher only in the last 5 minutes of CPR. A passive tidal volume (air going in and out the airways during compressions) was detected and found correlated to end tidal carbon dioxide.

Conclusions

The use of a suction cup on a piston-based chest compression device did not increase end tidal carbon dioxide, but it was associated to a higher coronary perfusion pressure.

The feasibility of emergency medical technicians performing intermittent high-quality cardiopulmonary resuscitation

Background: Whether intermittent chest compressions have an effect on the quality of CPR is worthy of discussion. The purpose of this study was to investigate differences in the chest compression quality of emergency medical technicians (EMTs) performing cardiopulmonary resuscitation (CPR) with different rest intervals. Methods: Seventy male firefighters with EMT licenses participated in this study. Participants completed body composition measurements and three CPR quality tests, as follows: (1) CPR-uninterrupted for 10 minutes; (2) after 2 days of rest, CPR 10s-intermittent (CPR-10s), for 2 minutes each time and 5 cycles; (3) after another 2 days of rest, CPR 20s-intermittent (CPR-20s), for 2 minutes each time and 5 cycles. Results: Body composition results showed that body mass (BM), body mass index (BMI), upper limb muscle mass (ULMM), core muscle mass (CMM), and upper limb-core muscle mass (UL+CMM) were positively correlated with chest compression depth (CCD) (p < 0.05). Analysis of the three different modes of CPR quality analysis indicated significant differences in the chest compression fraction (CCF, F = 6.801, p = 0.001), chest compression rebound rate (CCRR, F = 3.919, p = 0.021), and ratings of perceived exertion (RPE, F = 23.815, p < 0.001). Among the different performance cycles of CPR-10s, significant differences were found in CCF, CCD, CCR (chest compression rate), and RPE (p < 0.05). On the other hand, among the different performance cycles of CPR-20s, significant differences were found in CCD, CCR, and RPE (p < 0.05). Moreover, the CCF, CCD, and RPE scores of the two tests reached significant differences in specific phases (p < 0.05). Conclusions: This study confirmed that the upper limb muscle mass or the weight of the upper body of EMTs is positively correlated with the quality of CPR. In addition, intermittent chest compressions with safe interruption intervals can reduce fatigue caused by long-term chest compressions and maintain better chest compression quality.

A comprehensive review of randomized clinical trials in three medical journals reveals 396 medical reversals

The ability to identify medical reversals and other low-value medical practices is an essential prerequisite for efforts to reduce spending on such practices. Through an analysis of more than 3000 randomized controlled trials (RCTs) published in three leading medical journals (the Journal of the American Medical Association, the Lancet, and the New England Journal of Medicine), we have identified 396 medical reversals. Most of the studies (92%) were conducted on populations in high-income counties, cardiovascular disease was the most common medical category (20%), and medication was the most common type of intervention (33%).

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.

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.

Comparative effectiveness of standard CPR vs active compression-decompression CPR with CardioPump for treatment of cardiac arrest

BACKGROUND

Despite all of the studies conducted on cardiopulmonary resuscitation (CPR), the mortality rate of cardiac arrest patients is still high. This has led to a search for alternative methods. One of these methods is active compression-decompression CPR (ACD-CPR) performed with the CardioPump.

OBJECTIVE

The differences in the restoration of spontaneous circulation; the 1-, 7-, and 30-day survival rates; and hospital discharge rates between conventional CPR and ACD-CPR performed with CardioPump were investigated. In addition, the differences between the 2 methods with respect to complications were also investigated.

METHODS

Our study was a prospective, randomized medical device study with a case-control group. Cardiac arrest cases brought to our emergency medicine clinic by the 112 emergency ambulances from out of hospital and patients who had developed cardiac arrest inhospital clinics between April 2015 and September 2015 were included in our study. For randomization, standard CPR was performed on odd days of each month, and CPR using CardioPump was performed on the even days of each month.

RESULTS

A total of 181 patients were included in our study. The number of patients who received conventional CPR was determined as 86 (47.5%), and the number of patients who received CPR using the CardioPump was determined as 95 (52.5%). We did not identify any difference between conventional CPR and CardioPump ACD-CPR with respect to restoration of spontaneous circulation, discharge rates, and the 1-, 7-, and 30-day survival rates. (P=.384, P=.601, P=.997, P=.483, and P=.803, respectively) The complication rate was higher in the patient group that received conventional CPR (P<.001).

CONCLUSION

As a result of our study, we did not obtain any evidence supporting the replacement of conventional CPR with ACD-CPR performed using CardioPump.

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.

Capnography during cardiopulmonary resuscitation: Current evidence and future directions

Capnography continues to be an important tool in measuring expired carbon dioxide (CO₂). Most recent Advanced Cardiac Life Support (ACLS) guidelines now recommend using capnography to ascertain the effectiveness of chest compressions and duration of cardiopulmonary resuscitation (CPR). Based on an extensive review of available published literature, we selected all available peer-reviewed research investigations and case reports. Available evidence suggests that there is significant correlation between partial pressure of end-tidal CO₂ (PETCO₂) and cardiac output that can indicate the return of spontaneous circulation (ROSC). Additional evidence favoring the use of capnography during CPR includes definitive proof of correct placement of the endotracheal tube and possible prediction of patient survival following cardiac arrest, although the latter will require further investigations. There is emerging evidence that PETCO₂ values can guide the initiation of extracorporeal life support (ECLS) in refractory cardiac arrest (RCA). There is also increasing recognition of the value of capnography in intensive care settings in intubated patients. Future directions include determining the outcomes based on capnography waveforms PETCO₂ values and determining a reasonable duration of CPR. In the future, given increasing use of capnography during CPR large databases can be analyzed to predict outcomes.

[Mechanical resuscitation assist devices]

In Germany 100,000-160,000 people suffer from out-of-hospital cardiac arrest (OHCA) annually. The incidence of cardiopulmonary resuscitation (CPR) after OHCA varies between emergency ambulance services but is in the range of 30-90 CPR attempts per 100,000 inhabitants per year. Basic life support (BLS) involving chest compressions and ventilation is the key measure of resuscitation. Rapid initiation and quality of BLS are the most critical factors for CPR success. Even healthcare professionals are not always able to ensure the quality of CPR measures. Consequently in recent years mechanical resuscitation devices have been developed to optimize chest compression and the resulting circulation. In this article the mechanical resuscitation devices currently available in Germany are discussed and evaluated scientifically in context with available literature. The ANIMAX CPR device should not be used outside controlled trials as no clinical results have so far been published. The same applies to the new device Corpuls CPR which will be available on the market in early 2014. Based on the current published data a general recommendation for the routine use of LUCAS™ and AutoPulse® CPR cannot be given. The preliminary data of the CIRC trial and the published data of the LINC trial revealed that mechanical CPR is apparently equivalent to good manual CPR. For the final assessment further publications of large randomized studies must be analyzed (e.g. the CIRC and PaRAMeDIC trials). However, case control studies, case series and small studies have already shown that in special situations and in some cases patients will benefit from the automatic mechanical resuscitation devices (LUCAS™, AutoPulse®). This applies especially to emergency services where standard CPR quality is far below average and for patients who require prolonged CPR under difficult circumstances. This might be true in cases of resuscitation due to hypothermia, intoxication and pulmonary embolism as well as for patients requiring transport or coronary intervention when cardiac arrest persists. Three prospective randomized studies and the resulting meta-analysis are available for active compression-decompression resuscitation (ACD-CPR) in combination with an impedance threshold device (ITD). These studies compared ACD-ITD-CPR to standard CPR and clearly demonstrated that ACD-ITD-CPR is superior to standard CPR concerning short and long-term survival with good neurological recovery after OHCA.

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.

Active chest compression-decompression for cardiopulmonary resuscitation

BACKGROUND

Active compression-decompression cardiopulmonary resuscitation (ACDR CPR) uses a hand-held suction device, applied mid-sternum, to compress the chest then actively decompress the chest after each compression. Randomised controlled trials testing this device have shown discordant results.

OBJECTIVES

To determine the effect of active chest compression-decompression CPR compared to standard chest compression CPR on mortality and neurological function in adults with cardiac arrest treated either in-hospital or out-of-hospital.

SEARCH METHODS

We updated the searches of CENTRAL in The Cochrane Library (Issue 12 of 12, 2012), MEDLINE (OVID, 1946 to January week 1 2013), and EMBASE (OVID, 1980 to week 1 2013) on 14 January 2013. We checked the reference list of retrieved articles, contacted experts in the field, and searched ClinicalTrials.gov.

SELECTION CRITERIA

All randomised or quasi-randomised studies comparing active compression-decompression with standard manual chest compression in adults with a cardiac arrest who received cardiopulmonary resuscitation by a trained medical or paramedical team.

DATA COLLECTION AND ANALYSIS

We independently extracted data on an intention-to-treat basis. When needed, we contacted the authors of the primary studies. If appropriate, we cumulated studies and pooled relative risk (RR) estimates. We predefined subgroup analyses according to setting (out-of-hospital or in-hospital) and attending team composition (with physician or paramedic only).

MAIN RESULTS

In this update, 27 new related publications were found, but they did not all fulfil inclusion criteria or concerned participants already reported in previous publications. In the end, we included 10 trials in this review: Eight were in out-of-hospital settings; one was set in-hospital only; and one had both in-hospital and out-of-hospital components. Allocation concealment was adequate in four studies. The two in-hospital studies were different in quality and size (773 and 53 participants). Both found no differences between ACDR CPR and STR in any outcome.Out-of-hospital trials cumulated 4162 participants. There were no differences between ACDR CPR and STR for mortality either immediately (RR 0.98, 95% confidence interval (CI) 0.94 to 1.03) or at hospital discharge (RR 0.99, 95% CI 0.98 to 1.01). The pooled RR of neurological impairment of any severity was 1.71 (95% CI 0.90 to 3.25), with a non-significant trend to more frequent severe neurological damage in survivors of ACDR CPR (RR 3.11, 95% CI 0.98 to 9.83). However, assessment of neurological outcome was limited, and few participants had neurological damage.There was no difference between ACDR CPR and STR with regard to complications such as rib or sternal fractures, pneumothorax, or haemothorax (RR 1.09, 95% CI 0.86 to 1.38). Skin trauma and ecchymosis were more frequent with ACDR CPR.

AUTHORS' CONCLUSIONS

Active chest compression-decompression in people with cardiac arrest is not associated with any clear benefit.

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.

Cardiopulmonary resuscitation and management of cardiac arrest

The best chance of survival with a good neurological outcome after cardiac arrest is afforded by early recognition and high-quality cardiopulmonary resuscitation (CPR), early defibrillation of ventricular fibrillation (VF), and subsequent care in a specialist center. Compression-only CPR should be used by responders who are unable or unwilling to perform mouth-to-mouth ventilations. After the first defibrillator shock, further rhythm checks and defibrillation attempts should be performed after 2 min of CPR. The underlying cause of cardiac arrest can be identified and treated during CPR. Drugs have a limited effect on long-term outcomes after cardiac arrest, although epinephrine improves the success of resuscitation, and amiodarone increases the success of defibrillation for refractory VF. Supraglottic airway devices are an alternative to tracheal intubation, which should be attempted only by skilled rescuers. Care after cardiac arrest includes controlled reoxygenation, therapeutic hypothermia for comatose survivors, percutaneous coronary intervention, circulatory support, and control of blood-glucose levels and seizures. Prognostication in comatose survivors of cardiac arrest needs a careful, multimodal approach using clinical and electrophysiological assessments after at least 72 h.