Mechanical Chest Compression Devices Research Articles

Strategies to improve out-of-hospital cardiac arrest outcomes in the pre-hospital environment – Part A: pharmaceutical strategies

IntroductionHistorically, survival rates from out-of-hospital cardiac arrest (OHCA) have been low. In recent times, survival rates have increased substantially in some small population pockets, which sparked general interest in this field and the volume of research increased. Included was an increase in the number of strategies being investigated to improve outcomes. The aim of this review is to assemble these strategies and consolidate the findings of the pharmaceutical strategies.MethodsThis is a systematic search and review, rather than a systematic review. Four databases (MEDLINE, CINAHL, Informit, Scopus) were searched for papers published between 2007 and 2017 containing strategies that may be used by paramedics when resuscitating adult (18+ years) patients in cardiac arrest from presumed cardiac aetiology in the out-of-hospital environment. The search was undertaken in February 2017. Five separate search concepts were used on all databases. Each concept consisted of multiple search terms.ResultsThis review identified 28 separate studies for final review, which formulated six strategies. These were: use of a modified resuscitation protocol; use of a mechanical chest compression device; intra-thoracic pressure regulation; vasopressin administration; thrombolysis administration; application of therapeutic hypothermia. This paper reports on the full results of the pharmaceutical strategies (vasopressin or thrombolysis administration). Part B will address the non-pharmaceutical strategies.ConclusionThere is no evidence to support the introduction of vasopressin or thrombolysis use during OHCA. Future studies should focus on study design and specific patient subsets.

Registered nurses’ experiences of near misses in ambulance care – A critical incident technique study

BackgroundIn hospitals, potentially harmful near misses occur daily exposing patients to adverse events and safety risks. The same applies to ambulance care, but it is unclear what the risks are and why near misses arise. AimTo explore registered nurses’ experiences and behaviours associated with near misses where patient safety in the ambulance service was jeopardized. MethodsBased on critical incident technique, a retrospective and descriptive design with individual qualitative interviews was used. Ten men and five women from the Swedish ambulance service participated. ResultsSeventy-three critical incidents of near misses constituted four main areas: Drug management; Human-technology interactions; Assessment and care and Patient protection actions. Incidents were found in drug management with incorrect drug mixing and dosage. In human-technology interactions, near misses were found in handling of electrocardiography, mechanical chest compression devices and other equipment. Misjudgement and delayed treatment were found in patient assessments and care measures while patient protection actions failed in transport safety, hygiene and local area knowledge. ConclusionsExperiencing near misses led to stress, guilt and shame. The typical behaviour in response to near misses was to immediately correct the action. Occasionally, however, the near miss was not discovered until later without causing any harm.

Mechanical chest compression device use in patients in a non-shockable rhythm at in-hospital cardiac arrest: a multi-centre feasibility randomised controlled trial (COMPRESS-RCT)

Mechanical chest compression device use in patients in a non-shockable rhythm at in-hospital cardiac arrest: a multi-centre feasibility randomised controlled trial (COMPRESS-RCT)

Interruptions in CPR during deployment of a mechanical chest compression device: results from a randomised controlled trial (COMPRESS-RCT)

Purpose of the study: To describe duration in chest compression pauses associated with deployment of a mechanical chest compression device in a randomised controlled trial.

Does endotracheal intubation increases chest compression fraction in out of hospital cardiac arrest: A substudy of the CAAM trial

BackgroundOptimal out of hospital cardiac arrest (OHCA) airway management strategies remain unclear. We compared chest compression fraction (CCF) between patients receiving endotracheal intubation (ETI) versus bag mask ventilation (BMV). MethodsWe studied adult OHCA enrolled from our center in the CAAM trial. Primary exposures were ETI or BMV. Primary outcome was whole intervention CCF, adjusted for Utstein confounders. Secondary outcomes were per cycle CCF, no flow time associated (NFT) with ventilation, rhythms checks and mechanical chest compression device placement. ResultsOf 2040 OHCA enrolled in the CAAM trial we analyzed 112 cases recruited by our center. Unadjusted CCF was 0.89 for ETI and 0.88 for BMV (p = 0.19). Compared with BMV, ETI achieved lower NFT associated with ventilations (32 vs 127 s; p < 0.001). ETI cases experienced higher NFT associated with rhythm checks (69.5 vs 42.5 s p = 0.02) and with mechanical chest compression placement (29 vs 20 s; p = 0.04). CCF was higher during the first cycle in BMV than in ETI patients (0.81 vs 0.74; p = 0.02). After correction for confounders we observed no difference in global intervention CCF between the ETI and BMV (ΔCCF [ETI-BMV] 0.301; [95%CI: −1.9 to 2.51]; p = 0.79). ConclusionIn our substudy whole intervention CCF among OHCA was not modified by ETI compared to BMV. In the ETI group we observed lower NFT associated with ventilations and higher NFT associated with mechanical chest compression devices placement. CCF was lower in the ETI group during the first cycle.

Functionality and operational fitness of mechanical chest compression devices

Functionality and operational fitness of mechanical chest compression devices

Strategies to Improve Out-of-Hospital Cardiac Arrest Outcomes in the Pre-Hospital Environment – Part B: Non-Pharmaceutical Strategies

Introduction Out-of-hospital cardiac arrest (OHCA) historically has low survival rates. Higher rates of survival have recently developed in some small geographical areas, which pre-empted an increase in the volume of research in this field. The aim of this paper is to consolidate the findings of the strategies that do not focus on drugs. Methods This is a systematic search and review, rather than a systematic review. A search of four databases (MEDLINE, CINAHL, Informit, Scopus) was undertaken in February 2017. Papers published between 2007 and 2017 containing strategies that may be used by paramedics when resuscitating adult patients in OHCA from presumed cardiac aetiology were identified. Results Twenty-eight studies were included in the review, comprising six separate strategies. This manuscript reports on the four non-pharmaceutical strategies (use of a modified resuscitation protocol; use of a mechanical chest compression device; intra-thoracic pressure regulation and application of therapeutic hypothermia). Conclusion Use of a modified resuscitation protocol to improve the quality of cardiopulmonary resuscitation, was the only strategy showing evidence to warrant a recommendation for immediate implementation. Future studies should focus on strategy specific patient subsets.

GW29-e0549 Meta-analysis of mechanical versus manual chest compressions in cardiopulmonary resuscitation

The aim of this paper was to conduct a meta-analysis of the published literatures comparing the use of mechanical chest compression device and manual chest compression during cardiac arrest (CA) with respect to short-term survival outcomes and neurological function. Databases including MEDLINE,

Mechanical versus manual chest compressions in the treatment of in-hospital cardiac arrest patients in a non-shockable rhythm: a randomised controlled feasibility trial (COMPRESS-RCT)

BackgroundMechanical chest compression devices consistently deliver high-quality chest compressions. Small very low-quality studies suggest mechanical devices may be effective as an alternative to manual chest compressions in the treatment of adult in-hospital cardiac arrest patients. The aim of this feasibility trial is to assess the feasibility of conducting an effectiveness trial in this patient population.MethodsCOMPRESS-RCT is a multi-centre parallel group feasibility randomised controlled trial, designed to assess the feasibility of undertaking an effectiveness to compare the effect of mechanical chest compressions with manual chest compressions on 30-day survival following in-hospital cardiac arrest.Over approximately two years, 330 adult patients who sustain an in-hospital cardiac arrest and are in a non-shockable rhythm will be randomised in a 3:1 ratio to receive ongoing treatment with a mechanical chest compression device (LUCAS 2/3, Jolife AB/Stryker, Lund, Sweden) or continued manual chest compressions. It is intended that recruitment will occur on a 24/7 basis by the clinical cardiac arrest team. The primary study outcome is the proportion of eligible participants randomised in the study during site operational recruitment hours. Participants will be enrolled using a model of deferred consent, with consent for follow-up sought from patients or their consultee in those that survive the cardiac arrest event.The trial will have an embedded qualitative study, in which we will conduct semi-structured interviews with hospital staff to explore facilitators and barriers to study recruitment.DiscussionThe findings of COMPRESS-RCT will provide important information about the deliverability of an effectiveness trial to evaluate the effect on 30-day mortality of routine use of mechanical chest compression devices in adult in-hospital cardiac arrest patients.Trial registrationISRCTN38139840, date of registration 9th January 2017.

Mechanical versus manual chest compressions for cardiac arrest.

Mechanical chest compression devices have been proposed to improve the effectiveness of cardiopulmonary resuscitation (CPR). 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. 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. 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. We used standard methodological procedures expected by Cochrane. 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. 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.

Effect of compression waveform and resuscitation duration on blood flow and pressure in swine: One waveform does not optimally serve

BackgroundChest compression (CC) research primarily focuses on finding the ‘optimum’ compression waveform using a variety of compression efficacy metrics. Blood flow is rarely measured systematically with high fidelity. Using a programmable mechanical chest compression device, we studied the effect of inter-compression pauses in a swine model of cardiac arrest, testing the hypothesis that a single ‘optimal’ CC waveform exists based on measurements of resulting blood flow. MethodsHemodynamics were studied in 9 domestic swine (∼30 kg) using multiple flow probes and standard physiological monitoring. After 10 min of ventricular fibrillation, five mechanical chest compression waveforms (5.1 cm, varying inter-compression pauses) were delivered for 2 min each in a semi-random pattern, totaling 50 compression minutes. Linear Mixed Models were used to estimate the effect of compression waveform on hemodynamics. ResultsBlood flow and pressure decayed significantly with time in both arteries and veins. No waveform maximized blood flow in all vessels simultaneously and the waveform generating maximal blood flow in a specific vessel changed over time in all vessels. A flow mismatch between paired arteries and veins, e.g. abdominal aorta and inferior vena cava, also developed over time. The waveform with the slowest rate and shortest duty cycle had the smallest mismatch between flows after about 30 min of CPR. ConclusionsThis data challenges the concept of a single optimal CC waveform. Time dependent physiological response to compressions and no single compression waveform optimizing flow in all vessels indicate that current descriptions of CPR don’t reflect patient physiology.

A case of traumatic liver and spleen injuries after cardiopulmonary resuscitation by mechanical chest compression device, AutoPulse&lt;SUP&gt;®&lt;/SUP&gt;

A case of traumatic liver and spleen injuries after cardiopulmonary resuscitation by mechanical chest compression device, AutoPulse&lt;SUP&gt;®&lt;/SUP&gt;

Merits and demerits of AutoPulse&lt;SUP&gt;®&lt;/SUP&gt;, a mechanical chest compression device

Merits and demerits of AutoPulse&lt;SUP&gt;®&lt;/SUP&gt;, a mechanical chest compression device

Feasibility of data linkage in the PARAMEDIC trial: a cluster randomised trial of mechanical chest compression in out-of-hospital cardiac arrest

ObjectivesThere is considerable interest in reducing the cost of clinical trials. Linkage of trial data to administrative datasets and disease-specific registries may improve trial efficiency, but it has not been...

How Ventilation Is Delivered During Cardiopulmonary Resuscitation: An International Survey.

Recommendations regarding ventilation during cardiopulmonary resuscitation (CPR) are based on a low level of scientific evidence. We hypothesized that practices about ventilation during CPR might be heterogeneous and may differ worldwide. To address this question, we surveyed physicians from several countries on their practices during CPR. We used a Web-based opinion survey. Links to the survey were sent by e-mail newsletters and displayed on the Web sites of medical societies involved in CPR practice from December 2013 to March 2014. 1,328 surveys were opened, and 548 were completed (41%). Responses came from 54 countries, but 64% came from 6 countries. Responders were mostly physicians (89%). From this group, 97% declared following specific CPR guidelines. Regarding practices, 28% declared always or frequently adopting only continuous chest compressions without additional ventilation. With regard to mechanical chest compression devices, 38% responded that such devices were available to them; when used, 28% declared always or frequently experiencing problems with ventilation such as frequent alarms. During bag-mask ventilation in intubated patients, 18% declared stopping chest compression during insufflation, and 39% applied > 10 breaths/min, which conflicts with international CPR guidelines. When a ventilator was used, the volume controlled mode was the most common strategy cited, but there was heterogeneity regarding ventilator settings for PEEP, trigger, FIO2 , and breathing frequency. SpO2 and end-tidal CO2 were the 2 most monitored variables cited. Physicians indicated heterogeneous practices that often differ significantly from international CPR guidelines. This may reflect the low level of evidence and a lack of detailed recommendations concerning ventilation during CPR.

Haemodynamic outcomes during piston-based mechanical CPR with or without active decompression in a porcine model of cardiac arrest

BackgroundExperimental active compression-decompression (ACD) CPR is associated with increased haemodynamic outcomes compared to standard mechanical chest compressions. Since no clinically available mechanical chest compression device is capable of ACD-CPR, we modified the LUCAS 2 (Physio-Control, Lund, Sweden) to deliver ACD-CPR, hypothesising it would improve haemodynamic outcomes compared with standard LUCAS CPR on pigs with cardiac arrest.MethodsThe modified LUCAS delivering 5 cm compressions with or without 2 cm active decompression above anatomical chest level was studied in a randomized crossover design on 19 Norwegian domestic pigs. VF was electrically induced and untreated for 2 min. Each pig received ACD-CPR and standard mechanical CPR in three 180-s. phases. We measured aortic, right atrial, coronary perfusion, intracranial and oesophageal pressure, cerebral and carotid blood flow and cardiac output. Two-sided paired samples t-test was used for continuous parametric data and Wilcoxon test for non-parametric data. P < 0.05 was considered significant.ResultsDue to injuries/device failure, the experimental protocol was completed in nine of 19 pigs. Cardiac output (l/min, median, (25, 75-percentiles): 1.5 (1.1, 1.7) vs. 1.1 (0.8, 1.5), p < 0.01), cerebral blood flow (AU, 297 vs. 253, mean difference: 44, 95% CI; 14–74, p = 0.01), and carotid blood flow (l/min, median, (25, 75-percentiles): 97 (70, 106) vs. 83 (57, 94), p < 0.01) were higher during ACD-CPR compared to standard mechanical CPR. Coronary perfusion pressure (CPP) trended towards higher in end decompression phase.ConclusionCardiac output and brain blood flow improved with mechanical ACD-CPR and CPP trended towards higher during end-diastole compared to standard LUCAS CPR.

Mechanical circulatory support in terminal heart failure

After exhaustion of all conservative measures in the treatment of acute and chronic heart insufficiency, there is the possibility to temporarily or permanently support or replace the pump performance of the heart by mechanical circulatory support (MCS) systems. Presentation of the most important cardiac support systems for intensive care medicine, their indications and important risk factors. Critical review of device manufacturer's specifications, current research and expert opinions. The spectrum of available MCS procedures include mechanical chest compression devices, catheter-based micropumps and complete artificial hearts. Device selection depends on the severity of heart failure (monoventricular or biventricular pump failure), the expected duration of treatment and the degree of lung function impairment. The decision between minimally invasive and open surgical procedures depends on the options established at the specific healthcare institution and whether the heart function is to be temporarily or permanently replaced. Compliance with the anticoagulation regimens defined by the manufacturer is especially important as they differ vastly between devices and are critical to avoid bleeding or thromboembolic complications. Due to the increasing number of patients on long-term mechanical circulatory support, the chances are that physicians in the initial emergency admission are unfamiliar with these devices but need to operate them in emergency cases. Therefore, knowledge of these procedures and their complications becomes increasingly important.

News in Cardiopulmonary Resuscitation

For the first time, the european guidelines for cardiopulmonary resuscitation (CPR) have been updated by the ILCOR indecember 2017. If new data and findings are available, these guidelines can also be updated outside the 5-year cycle. Thus, it is now recommended that, depending on the level of training of the layer, a chest-compression-only CPR or in combination with ventilation should be done. The important function of the dispatchers in the context of telephone or dispatcher-assisted CPR is emphasized by the demand of a structured training. The use of mechanical chest compression devices remains reserved only for special situations.

Training approaches for the deployment of a mechanical chest compression device: a randomised controlled manikin study

ObjectivesTo evaluate the effect of training strategy on team deployment of a mechanical chest compression device.DesignRandomised controlled manikin trial.SettingLarge teaching hospital in the UK.ParticipantsTwenty teams, each comprising three clinicians. Participating...

Severe Hypothermia Management in Mountain Rescue: A Survey Study.

Podsiadło, Paweł, Tomasz Darocha, Sylweriusz Kosiński, Kinga Sałapa, Mirosław Ziętkiewicz, Tomasz Sanak, Rachel Turner, and Hermann Brugger. Severe hypothermia management in mountain rescue: A survey study. High Alt Med Biol 18:411–416, 2017.Introduction: Severe hypothermia is a rare but demanding medical emergency. Although mortality is high, if well managed, the neurological outcome of survivors can be excellent. The aim of the study was to assess whether mountain rescue teams (MRTs) are able to meet the guidelines in the management of severe hypothermia, regarding their equipment and procedures.Methods: Between August and December 2016, an online questionnaire, with 24 questions to be completed using Google Forms, was sent to 123 MRTs in 27 countries.Results: Twenty-eight MRTs from 10 countries returned the completed questionnaire. Seventy-five percent of MRTs reportedly provide advanced life support (ALS) on-site and 89% are regularly trained in hypothermia management. Thirty-two percent of MRTs transport hypothermic patients in cardiac arrest to the nearest hospital instead of an Extracorporeal Life Support facility; 39% are equipped with mechanical chest compression devices; 36% measure core body temperature on-site and no MRT is equipped with a device to measure serum potassium concentration on-site in avalanche victims.Conclusions: Most MRTs are regularly trained in the treatment of severe hypothermia and provide ALS. The majority are not equipped to follow standard procedural guidelines for the treatment of severely hypothermic patients, especially with cardiac arrest. However, the low response rate—23% (28/123)—could have induced a bias.