Impact of personal protective equipment on the effectiveness of chest compression - A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: To assess the impact of personal protective equipment (PPE) on different aspects of chest compression (CC) during cardiopulmonary resuscitation, we conducted this study. METHODS: This systematic review was performed according to the PRISMA. We searched PubMed, EMBASE and Web of Science from inception to June-6, 2020, limiting to the studies that reported the comparison of the effectiveness of CC in terms of CC rate, CC depth, the proportion of adequate CC rate, the proportion of adequate CC depth or proportion of adequate recoil; in study arms with or without PPE. Risk of bias was assessed by the ROB-2 and ROBINS-I tool. Quantitative data synthesis was done using the generic inverse variance method and the fixed-effects model. RESULTS: Five simulation-based studies were finally included. A Significant decrease in CC rate (SMD: -0.28, 95%CI: -0.47 to -0.10) and CC depth (SMD: -0.26, 95%CI: -0.44 to -0.07) were observed in the PPE arm as compared to the no-PPE arm. The difference in CC rate was more prominently seen in adult CPR than in paediatric CPR. Without PPE, the proportion of adequate CC rate delivered was 0.74, which reduced significantly to 0.60 after use of PPE (p - 0.035). Similarly, the proportion of adequate CC depth was significantly lesser (p - 0.001) in PPE arm (0.55), as compared to that of the no-PPE arm (0.78). CONCLUSION: The use of PPE compromises the quality of CC during CPR significantly, and newer ways to deliver chest compression has to be investigated. This study was prospectively registered in PROSPERO (CRD42020192031).

An optimal chest compression technique using personal protective equipment during resuscitation in the COVID-19 pandemic: a randomized crossover simulation study.

BACKGROUND: Cardiopulmonary resuscitation with the use of personal protective equipment (PPE) for aerosol generating procedures (AGP) in patients with suspected or confirmed coronavirus disease 2019 (COVID­19) remains challenging. AIMS: The aim of this study was to compare 3 chest compression (CC) methods used by paramedics wearing PPE. METHODS: The single­blinded, multicenter, randomized, crossover simulation study involved 67 paramedics wearing PPE AGP. They performed 2­minute continuous CCs in an adult with suspected or confirmed COVID­19 in 3 scenarios: 1) manual CCs; 2) CCs with the TrueCPR feedback device; 3) CCs with the LUCAS 3 mechanical CC device. RESULTS: The depth of CC was more frequently correct when using LUCAS 3 compared with TrueCPR and manual CC (median [IQR] 51 [50-55] mm vs 47 [43-52] mm vs 43 [38-46] mm; P = 0.005). This was also true for the CC rate (median [IQR]102 [100-102] compressions per minute [CPM] vs 105 [98-1114] CPM vs 116 [112-129] CPM; P = 0.027) and chest recoil (median [IQR]100% [98%-100%] vs 83% [60%-92%] vs 39% [25%-50%]; P = 0.001). A detailed analysis of 2­minute resuscitation with manual CCs showed a decrease in compression depth and full chest recoil after 1 minute of CCs. CONCLUSION: We demonstrated that during simulated resuscitation with the use of PPE AGP in patients with suspected or confirmed COVID­19, CC with LUCAS 3 compared with manual CCs as well as the TrueCPR essentially increased the CC quality. In the case of manual CCs by paramedics dressed in PPE AGP, it is advisable to change the person performing resuscitation every minute.

Impacts of chest compression cycle length and real-time feedback with a CPRmeter® on chest compression quality in out-of-hospital cardiac arrest: study protocol for a multicenter randomized controlled factorial plan trial.

BACKGROUND: With a survival rate of 6 to 11%, out-of-hospital cardiac arrest (OHCA) remains a healthcare challenge with room for improvement in morbidity and mortality. The guidelines emphasize the highest possible quality of cardiopulmonary resuscitation (CPR) and chest compressions (CC). It is essential to minimize CC interruptions, and therefore increase the chest compression fraction (CCF), as this is an independent factor for survival. Survival is significantly and positively correlated with the suitability of CCF targets, CC frequency, CC depth, and brief predefibrillation pause. CC guidance improves adherence to recommendations and allows closer alignment with the CC objectives. The possibility of improving CCF by lengthening the time between two CC relays and the effect of real-time feedback on the quality of the CC must be investigated. METHODS: Using a 2 × 2 factorial design in a multicenter randomized trial, two hypotheses will be tested simultaneously: (i) a 4-min relay rhythm improves the CCF (reducing the no-flow time) compared to the currently recommended 2-min relay rate, and (ii) a guiding tool improves the quality of CC. Primary outcomes (i) CCF and (ii) correct compression score will be recorded by a real-time feedback device. Five hundred adult nontraumatic OHCAs will be included over 2 years. Patients will be randomized in a 1:1:1:1 distribution receiving advanced CPR as follows: 2-min blind, 2 min with guidance, 4-min blind, or 4 min with guidance. Secondary outcomes are the depth, frequency, and release of CC; length (care, no-flow, and low-flow); rate of return of spontaneous circulation; characteristics of advanced CPR; survival at hospital admission; survival and neurological state on days 1 and 30 (or intensive care discharge); and dosage of neuron-specific enolase on days 1 and 3. DISCUSSION: This study will contribute to assessing the impact of real-time feedback on CC quality in practical conditions of OHCA resuscitation. It will also provide insight into the feasibility of extending the relay rhythm between two rescuers from the currently recommended 2 to 4 min. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03817892 . Registered on 28 January 2019.

Real-time feedback improves chest compression quality in out-of-hospital cardiac arrest: A prospective cohort study.

BACKGROUND: Current guidelines underline the importance of high-quality chest compression during cardiopulmonary resuscitation (CPR), to improve outcomes. Contrary to this many studies show that chest compression is often carried out poorly in clinical practice, and long interruptions in compression are observed. This prospective cohort study aimed to analyse whether chest compression quality changes when a real-time feedback system is used to provide simultaneous audiovisual feedback on chest compression quality. For this purpose, pauses in compression, compression frequency and compression depth were compared. METHODS: The study included 292 out-of-hospital cardiac arrests in three consecutive study groups: first group, conventional resuscitation (no-sensor CPR); second group, using a feedback sensor to collect compression depth data without real-time feedback (sensor-only CPR); and third group, with real-time feedback on compression quality (sensor-feedback CPR). Pauses and frequency were analysed using compression artefacts on electrocardiography, and compression depth was measured using the feedback sensor. With this data, various parameters were determined in order to be able to compare the chest compression quality between the three consecutive groups. RESULTS: The compression fraction increased with sensor-only CPR (group 2) in comparison with no-sensor CPR (group 1) (80.1% vs. 87.49%; P < 0.001), but there were no further differences belonging compression fraction after activation of sensor-feedback CPR (group 3) (P = 1.00). Compression frequency declined over the three study groups, reaching the guideline recommendations (127.81 comp/min vs. 122.96 comp/min, P = 0.02 vs. 119.15 comp/min, P = 0.008) after activation of sensor-feedback CPR (group 3). Mean compression depth only changed minimally with sensor-feedback (52.49 mm vs. 54.66 mm; P = 0.16), but the fraction of compressions with sufficient depth (at least 5 cm) and compressions within the recommended 5-6 cm increased significantly with sensor-feedback CPR (56.90% vs. 71.03%; P = 0.003 and 28.74% vs. 43.97%; P < 0.001). CONCLUSIONS: The real-time feedback system improved chest compression quality regarding pauses in compression and compression frequency and facilitated compliance with the guideline recommendations. Compression depth did not change significantly after activation of the real-time feedback. Even the sole use of a CPR-feedback-sensor ("sensor-only CPR") improved performance regarding pauses in compression and compression frequency, a phenomenon known as the 'Hawthorne effect'. Based on this data real-time feedback systems can be expected to raise the quality level in some parts of chest compression quality. TRIAL REGISTRATION: International Clinical Trials Registry Platform of the World Health Organisation and German Register of Clinical Trials (DRKS00009903), Registered 09 February 2016 (retrospectively registered).

Comparison of in-hospital use of mechanical chest compression devices for out-of-hospital cardiac arrest patients: AUTOPULSE vs LUCAS.

This study aimed to investigate the prognostic difference between AUTOPULSE and LUCAS for out-of-hospital cardiac arrest (OHCA) adult patients.A retrospective observational study was performed nationwide. Adult OHCA patients after receiving in-hospital mechanical chest compression from 2012 to 2016 were included. The primary outcomes were sustained return of spontaneous circulation (ROSC) of more than 20 minutes and survival to discharge.Among 142,906 OHCA patients, 820 patients were finally included. In multivariate analysis, female (OR, 0.57; 95% CI, 0.33-0.99), witnessed arrest (OR, 2.10; 95% CI, 1.20-3.69), and arrest cause of non-cardiac origin (OR, 0.25; 95% CI, 0.10-0.62) were significantly associated with the increase in ROSC. LUCAS showed a lower survival than AUTOPULSE (OR, 0.23; 95% CI, 0.06-0.84), although it showed no significant association with ROSC. Percutaneous coronary intervention (OR, 6.30; 95% CI, 1.53-25.95) and target temperature management (TTM; OR, 7.30; 95% CI, 2.27-23.49) were the independent factors for survival. We categorized mechanical CPR recipients by witness to compare prognostic effectiveness of AUTOPULSE and LUCAS. In the witnessed subgroup, female (OR, 0.46; 95% CI, 0.24-0.89) was a prognostic factor for ROSC and shockable rhythm (OR, 5.04; 95% CI, 1.00-25.30), percutaneous coronary intervention (OR, 12.42; 95% CI, 2.04-75.53), and TTM (OR, 9.03; 95% CI, 1.86-43.78) for survival. In the unwitnessed subgroup, no prognostic factors were found for ROSC, and TTM (OR, 99.00; 95% CI, 8.9-1100.62) was found to be an independent factor for survival. LUCAS showed no significant increase in ROSC or survival in comparison with AUTOPULSE in both subgroups.The in-hospital use of LUCAS may have a deleterious effect for survival compared with AUTOPULSE.

Kinetics of manual and automated mechanical chest compressions.

AIM: Early onset of adequate chest compression is mandatory for cardiopulmonary resuscitation (CPR) following cardiac arrest. Transmission of forces from chest strain to the heart may be variable between manual and mechanical chest compressions. Furthermore, automated mechanical chest devices can deliver an active decompression, thus improving the venous return to the heart. This pilot study investigated the kinetics of cardiac deformation during these two CPR methods. METHODS: Transesophageal echocardiographic analysis of the right ventricular wall behind the sternum during CPR was assessed during manual and mechanical chest compression in adult patients admitted to the emergency department for out-of-hospital cardiac arrest. RESULTS: 9 patients had manual and 11 mechanical chest compression. Mechanical chest compression was characterized by greater right ventricular lateral wall displacement [with a median (IQR) of 3.7 (3.12-4.27) vs. 2.53 (2.27-2.6) cm, p < 0.0001], and lower rising time [123 (102-169) vs. 187 (164-215) ms, p = 0.002], relaxing time [109 (102-127) vs. 211 (133-252) ms, p = 0.0003], compression rate [100.6 (99.6-102.2) vs. 131.9 (125.4-151.4) bpm, p < 0.0001], with compression-decompression time ratio of [1.04 (0.86-1.1) vs. 0.86 (0.78-0.96), p = 0.046]. CONCLUSION: Mechanical compared to manual chest compression delivered a more rapid compression and decompression of the cardiac structures at an adequate rate, with broader inward-outward movement of the ventricular walls suggesting greater emptying and filling of the ventricles. Transesophageal echocardiography may be a useful tool to assess the adequacy of chest compression without CPR interruption.

Cardiac Arrest in the Cardiac Catheterization Laboratory: Combining Mechanical Chest Compressions and Percutaneous LV Assistance.

OBJECTIVES: The aim of this study was to evaluate the optimal treatment approach for cardiac arrest (CA) occurring in the cardiac catheterization laboratory. BACKGROUND: CA can occur in the cath lab during high-risk percutaneous coronary intervention. While attempting to correct the precipitating cause of CA, several options are available to maintain vital organ perfusion. These include manual chest compressions, mechanical chest compressions, or a percutaneous left ventricular assist device. METHODS: Eighty swine (58 ± 10 kg) were studied. The left main or proximal left anterior descending artery was occluded. Ventricular fibrillation (VFCA) was induced and circulatory support was provided with 1 of 4 techniques: either manual chest compressions (frequently interrupted), mechanical chest compressions with a piston device (LUCAS-2), an Impella 2.5 L percutaneously placed LVAD, or the combination of mechanical chest compressions and the percutaneous left ventricular assist device. The study protocol included 12 min of left main coronary occlusion, reperfusion, with defibrillation attempted after 15 min of VFCA. Primary outcome was favorable neurological function (CPC 1 or 2) at 24 h, while secondary outcomes included return of spontaneous circulation and hemodynamics. RESULTS: Manual chest compressions provided fewer neurologically intact surviving animals than the combination of a mechanical chest compressor and a percutaneous LVAD device (0% vs. 56%; p < 0.01), while no difference was found between the 2 mechanical approaches (28% vs. 35%: p = 0.75). Comparing integrated coronary perfusion pressure showed sequential improvement in hemodynamic support with mechanical devices (401 ± 230 vs. 1,337 ± 905 mm Hg/s; p = 0.06). CONCLUSIONS: Combining 2 mechanical devices provided superior 24-h survival with favorable neurological recovery compared with manual compressions during moderate duration VFCA associated with an acute coronary occlusion in the animal catheterization laboratory.

Nueva técnica de masaje cardíaco en lactantes / A new chest compression technique in infants

Objetivo: Comparar en un maniquí de lactante la calidad de las compresiones torácicas según el método tradicional (MT) o según la nueva técnica de 2pulgares con puños cerrados (NM). Diseño: Estudio controlado, aleatorizado y cruzado en profesionales. Ámbito: Hospital Universitario con UCI Pediátrica del norte de España. Participantes: Residentes y enfermeros de Pediatría, habiendo superado un curso de RCP básica y avanzada pediátrica. Intervenciones: Análisis cuantitativo de calidad de compresiones torácicas en escenario de RCP en lactante durante 2 min, mediante el sistema SimPad(R) con SkillReporter(TM) de Laerdal. Variables de interés principales: Frecuencia media y porcentaje de compresiones en rango recomendada, profundidad media y porcentaje de compresiones en rango recomendado, porcentaje de compresiones con descompresión adecuada y porcentaje de compresiones realizadas con los dedos en el centro del tórax. Resultados: La calidad global de las compresiones (NM: 84,2±23,7% vs. MT: 80,1±25,4% [p=0,25; no sig.]), el porcentaje de compresiones con profundidad correcta (NM: 59,9±35,8% vs. MT: 59,5±35,7% [p=0,76; no sig.]), la profundidad media alcanzada (NM: 37,3±3,8mm vs. MT: 36±5,3mm [p=0,06; no sig.]), el porcentaje de reexpansión completa de la caja torácica (NM: 94,4±9,3% vs. MT: 92,4±18,3% [p=0,58; no sig.]) y el porcentaje de compresiones con la frecuencia recomendada (NM: 62,2±34,6% vs. MT: 51±37,2% [p=0,13; no sig.]) fueron similares con los 2métodos. Conclusiones: La calidad de compresiones torácicas con el nuevo método (pulgares con los puños cerrados) es similar a la obtenida con el método tradicional

Objective: To compare the quality of chest compressions performed according to the classical technique (MT) versus a new technique (NM) (compression with 2thumbs with closed fists) in an infant manikin. Design: A controlled, randomized cross-over study was carried out in professionals assisting pediatric patients. Setting: A University Hospital with a Pediatric ICU in the north of Spain. Participants: Residents and nurses in Pediatrics who had completed a basic and an advanced pediatric cardiopulmonary resuscitation course. Interventions: Quantitative analysis of the variables referred to chest compression quality in a 2-minute cardiopulmonary resuscitation scenario in infants. Laerdal's SimPad(R) with SkillReporter(TM) system was used. Main variables of interest: Mean rate and percentage of compressions in the recommended rate range, mean depth and percentage of compressions within the depth range of recommendations, percentage of compressions with adequate decompression, and percentage of compressions performed with the fingers in the center of the chest. Results: Global quality of the compressions (NM: 84.2±23.7% vs. MT: 80.1±25.4% [p=0.25; p=ns]), percentage of compressions with correct depth (NM: 59.9±35.8% vs. MT: 59.5±35.7% [p=0.76; p=ns]), mean depth reached (NM: 37.3±3.8mm vs. MT: 36±5.3mm [p=0.06; p=ns]), percentage of complete re-expansion of the chest (NM: 94.4±9.3% vs. MT: 92.4±18.3% [p=0.58; p=ns]), and percentage of compressions with the recommended rate (NM: 62.2±34.6% vs. MT: 51±37.2% [p=0.13; p=ns]) proved similar with both methods. Conclusions: The quality of chest compressions with the new method (thumbs with closed fists) is similar to that afforded by the traditional method

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

BACKGROUND: International resuscitation guidelines emphasize the importance of high quality chest compressions, including correct chest compression depth and rate and complete chest recoil. The aim of the study was to assess the role of the TrueCPR device in the process of teaching cardiopulmonary resuscitation in nursing students. METHODS: A prospective randomized experimental study was performed among 94 first year students of nursing. On the next day, the participants were divided into 2 groups-the control group practiced chest compressions without the use of any device for half an hour, and the experimental group practiced with the use of TrueCPR. Further measurement of chest compressions was performed after a month. RESULTS: The chest compression rate achieved the value of 113 versus 126 (P < .001), adequate chest compression rate (%) was 86 versus 68 (P < .001), full chest release (%) 92 versus 69 (P = .001), and correct hand placement (%) 99 versus 99 (P, not significant) in TrueCPR and standard BLS groups, respectively. As for the assessment of the confidence of chest compression quality, 1 month after the training, the evaluation in the experimental group was statistically significantly higher (91 vs 71; P < .001) than in the control group. CONCLUSIONS: Cardiopulmonary resuscitation training with the use of the TrueCPR device is associated with better resuscitation skills 1 month after the training. The participants using TrueCPR during the training achieved a better chest compression rate and depth with in international recommendations and better full chest release percentage and self-assessed confidence of chest compression quality comparing with standard cardiopulmonary resuscitation training.

Load distributing band device for mechanical chest compressions: An Utstein-categories based analysis of survival to hospital discharge.

PURPOSE: The role of load distributing band device (LDB, AutoPulse®, Zoll Medical Corporation, Chelmsford, MA, USA) in out-of-hospital cardiac arrest is still a matter of debate, with few studies reaching conflicting results available in literature. We sought to assess whether the use of the LBD device could affect survival to hospital discharge in the different Utstein categories. MATERIALS AND METHODS: All consecutive patients enrolled in our provincial cardiac arrest registry (Pavia CARe) from January 2015 to December 2017 were included and pre-hospital data were computed as well as survival to hospital discharge. RESULTS: Among 1401 resuscitation attempts, the LDB device was used in 235 (17%) patients. The LDB device was significantly more used for shockable cardiac arrest (42.6% vs 13.7%, p < 0.001). The rate of ROSC and of survival to hospital discharge in the LDB group compared to the manual group was 40% vs 17% (p < 0.001) and 10% vs 7% (p = 0.2), respectively. However, after correction for independent predictors of LDB use, LDB device was a strong independent predictor of survival to hospital discharge only for non-shockable witnessed OHCA [n = 624/1401, OR 11.9 (95% CI 1.5-95.2), p = 0.02]. In this categories of patients LDB group showed longer resuscitation time [49.3 min (IQR 37-71) vs 23.6 (IQR 15-35), p < 0.001] and a higher rate of conversion to a shockable rhythm (33/83 = 40% vs 29/541 = 5%, p < 0.001). CONCLUSION: Utstein categories-based analysis showed that the LDB device positively affect survival to hospital discharge for non-shockable witnessed cardiac arrests with a neutral effect for shockable rhythms.

Cardiovascular risk factors differently affect the survival of patients undergoing manual or mechanical resuscitation.

BACKGROUND: Chest compression is a decisive element of cardio-pulmonary resuscitation (CPR). By applying a mechanical CPR device, compression interruptions can be minimised. We examined the efficiency of manual and device-assisted resuscitation as well as the effects of cardiovascular risk factors on the outcome of resuscitation. METHODS: In our retrospective, randomised 3-year study the data of adult patients suffering non-traumatic, out-of-hospital, sudden cardiac death (SCD) were analysed (n = 287). The data were retrieved by processing case reports, Utstein sheets and acute coronary syndrome sheets. We compared the data of patients undergoing manual (n = 232) and device-assisted resuscitation (LUCAS-2, n = 55). The primary endpoint was the on-site restoration of spontaneous circulation (ROSC). RESULTS AND CONCLUSION: In 37% of the cases ROSC happened. With respect to ROSC an insignificantly more favourable tendency was demonstrated in the case of device-assisted resuscitation (p = 0.072). In the Lucas group, a higher success rate occurred even in the case of prolonged resuscitation. We found a better outcome in the Lucas group in the case of CPR started a longer time after the SCD (p < 0.05). A positive correlation was established between age and unsuccessful resuscitation (p = < 0.017; r = 0.125). An unfavourable correlation was observed between hypertension and the outcome of resuscitation (p = 0.018; r = 0.143). According to our results the presence of left ventricular hypertrophy poses 5.1-fold risk of unsuccessful CPR (CI: 4.97-5.29). Advanced age and structural heart diseases can play a role in the genesis of SCD. Importantly, left ventricular hypertrophy and hypertension negatively affect survival.

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).

BACKGROUND: Mechanical 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. METHODS: COMPRESS-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. DISCUSSION: The 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 REGISTRATION: ISRCTN38139840 , date of registration 9th January 2017.

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.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Efficacy and safety of mechanical versus manual compression in cardiac arrest - A Bayesian network meta-analysis.

AIM: To compare relative efficacy and safety of mechanical compression devices (AutoPulse and LUCAS) with manual compression in patients with cardiac arrest undergoing cardiopulmonary resuscitation (CPR). METHODS: For this Bayesian network meta-analysis, seven randomized controlled trials (RCTs) were selected using PubMed/Medline, EMBASE, and CENTRAL (Inception- 31 October 2017). For all the outcomes, median estimate of odds ratio (OR) from the posterior distribution with corresponding 95% credible interval (Cr I) was calculated. Markov chain Monte Carlo (MCMC) modeling was used to estimate the relative ranking probability of each intervention based on surface under the cumulative ranking curve (SUCRA). RESULTS: In analysis of 12, 908 patients with cardiac arrest [AutoPulse (2, 608 patients); LUCAS (3, 308 patients) and manual compression (6, 992 patients)], manual compression improved survival at 30 days or hospital discharge (OR, 1.40, 95% Cr I, 1.09-1.94), and neurological recovery (OR, 1.51, 95% Cr I, 1.06-2.39) compared to AutoPulse. There were no differences between LUCAS and AutoPulse with regards to survival to hospital admission, neurological recovery or return of spontaneous circulation (ROSC). Manual compression reduced the risk of pneumothorax (OR, 0.56, 95% Cr I, 0.33-0.97); while, both manual compression (OR, 0.15, 95% Cr I, 0.01-0.73) and LUCAS (OR, 0.07, 95% Cr I, 0.00-0.43) reduced the risk of hematoma formation compared to AutoPulse. Probability analysis ranked manual compression as the most effective treatment for improving survival at 30 days or hospital discharge (SUCRA, 84%). CONCLUSIONS: Manual compression is more effective than AutoPulse and comparable to LUCAS in improving survival at 30 days or hospital discharge and neurological recovery. Manual compression had lesser risk of pneumothorax or hematoma formation compared to AutoPulse.