Top 5 barriers in cardiac arrest research as perceived by international early career researchers - A consensus study.

Aim of the study: Cardiac arrest research has not received as much scientific attention as research on other topics. Here, we aimed to identify cardiac arrest research barriers from the perspective of an international group of early career researchers. Methods: Attendees of the 2022 international masterclass on cardiac arrest registry research accompanied the Global Out-of-Hospital Cardiac Arrest Registry collaborative meeting in Utstein, Norway, and used an adapted hybrid nominal group technique to obtain a diverse and comprehensive perspective. Barriers were identified using a web-based questionnaire and discussed and ranked during an in-person follow-up meeting. After each response was discussed and clarified, barriers were categorized and ranked over two rounds. Each participant scored these from 1 (least significant) to 5 (most significant). Results: Nine participants generated 36 responses, forming seven overall categories of cardiac arrest research barriers. "Allocated research time" was ranked first in both rounds. "Scientific environment", including appropriate mentorship and support systems, ranked second in the final ranking. "Resources", including funding and infrastructure, ranked third. "Access to and availability of cardiac arrest research data" was the fourth-ranked barrier. This included data from the cardiac arrest registries, medical devices, and clinical studies. Finally, "uniqueness" was the fifth-ranked barrier. This included ethical issues, patient recruitment challenges, and unique characteristics of cardiac arrest. Conclusion: By identifying cardiac arrest research barriers and suggesting solutions, this study may act as a tool for stakeholders to focus on helping early career researchers overcome these barriers, thus paving the road for future research.

[Layperson basic life support education in Austria: An overview]. / Laienreanimationstraining in Österreich: Eine Übersicht und Annäherung.

Early interventions of laypersons can improve the survival and neurological outcome in patients with out-of-hospital cardiac arrest. There are several organizations in Austria which train lay people in basic life support and raise awareness for sudden cardiac death. To obtain an overview of the various initiatives, a questionnaire was sent to 26 organizations, and 15 of the organizations (58%) replied. The geographical distribution of the organizations between rural and urban areas was illustrated in a map. Most of them are situated in a university city, resulting in accessibility disparities for individuals in urban and rural settings. Layperson resuscitation education in Austria is largely dependent on the individual commitments of volunteers. The time spent practicing chest compressions in resuscitation courses ranges from 25% to 90% of the total course time. Furthermore, reasons for a lack of scientific endeavours could be identified, and solutions are suggested. Through better networking between organizations and initiatives, more laypersons could be trained in the future, which would lead to improved survival chances for persons suffering from out-of-hospital cardiac arrest in Austria. Appropriate support by political bodies and public authorities is and will remain a key element.

Out of sight - Out of mind? The need for a professional and standardized peri-mission first responder support model.

First responders are an essential part of the chain (-mail) of survival as they bridge and reduce the time to first chest compressions and defibrillation substantially. However, in the peri-mission phase before and after being sent to a cardiac arrest, these first responders are in danger of being forgotten and taken for granted, and the potential psychological impact has to be remembered. We propose a standardized first responder support system (FRSS) that needs to ensure that first responders are valued and cared for in terms of psychological safety and continuing motivation. This multi-tiered program should involve tailored education and standardized debriefing, as well as actively seeking contact with the first responders after their missions to facilitate potentially needed professional psychological support.

Accelerometry-Based Classification of Circulatory States During Out-of-Hospital Cardiac Arrest.

OBJECTIVE: Exploit accelerometry data for an automatic, reliable, and prompt detection of spontaneous circulation during cardiac arrest, as this is both vital for patient survival and practically challenging. METHODS: We developed a machine learning algorithm to automatically predict the circulatory state during cardiopulmonary resuscitation from 4-second-long snippets of accelerometry and electrocardiogram (ECG) data from pauses of chest compressions of real-world defibrillator records. The algorithm was trained based on 422 cases from the German Resuscitation Registry, for which ground truth labels were created by a manual annotation of physicians. It uses a kernelized Support Vector Machine classifier based on 49 features, which partially reflect the correlation between accelerometry and electrocardiogram data. RESULTS: Evaluating 50 different test-training data splits, the proposed algorithm exhibits a balanced accuracy of 81.2%, a sensitivity of 80.6%, and a specificity of 81.8%, whereas using only ECG leads to a balanced accuracy of 76.5%, a sensitivity of 80.2%, and a specificity of 72.8%. CONCLUSION: The first method employing accelerometry for pulse/no-pulse decision yields a significant increase in performance compared to single ECG-signal usage. SIGNIFICANCE: This shows that accelerometry provides relevant information for pulse/no-pulse decisions. In application, such an algorithm may be used to simplify retrospective annotation for quality management and, moreover, to support clinicians to assess circulatory state during cardiac arrest treatment.

Mechanical ventilation with ten versus twenty breaths per minute during cardio-pulmonary resuscitation for out-of-hospital cardiac arrest: A randomised controlled trial.

AIM OF THE STUDY: This study sought to assess the effects of increasing the ventilatory rate from 10 min-1 to 20 min-1 using a mechanical ventilator during cardio-pulmonary resuscitation (CPR) for out-of-hospital cardiac arrest (OHCA) on ventilation, acid-base-status, and outcomes. METHODS: This was a randomised, controlled, single-centre trial in adult patients receiving CPR including advanced airway management and mechanical ventilation offered by staff of a prehospital physician response unit (PRU). Ventilation was conducted using a turbine-driven ventilator (volume-controlled ventilation, tidal volume 6 ml per kg of ideal body weight, positive end-expiratory pressure (PEEP) 0 mmHg, inspiratory oxygen fraction (FiO2) 100%), frequency was pre-set at either 10 or 20 breaths per minute according to week of randomisation. If possible, an arterial line was placed and blood gas analysis was performed. RESULTS: The study was terminated early due to slow recruitment. 46 patients (23 per group) were included. Patients in the 20 min-1 group received higher expiratory minute volumes [8.8 (6.8-9.9) vs. 4.9 (4.2-5.7) litres, p < 0.001] without higher mean airway pressures [11.6 (9.8-13.6) vs. 9.8 (8.5-12.0) mmHg, p = 0.496] or peak airway pressures [42.5 (36.5-45.9) vs. 41.4 (32.2-51.7) mmHg, p = 0.895]. Rates of ROSC [12 of 23 (52%) vs. 11 of 23 (48%), p = 0.768], median pH [6.83 (6.65-7.05) vs. 6.89 (6.80-6.97), p = 0.913], and median pCO2 [78 (51-105) vs. 86 (73-107) mmHg, p > 0.999] did not differ between groups. CONCLUSION: 20 instead of 10 mechanical ventilations during CPR increase ventilation volumes per minute, but do not improve CO2 washout, acidaemia, oxygenation, or rate of ROSC. CLINICALTRIALS: gov Identifier: NCT04657393.

Assessing the weak links - Necessity and impact of regional cardiac arrest awareness campaigns for laypersons.

Introduction: Public knowledge of out-of-hospital cardiac arrest (OHCA), and initiation of basic life support (BLS) is crucial to increase survival in OHCA. Methods: The study analysed the knowledge and willingness to perform BLS of laypersons passing an AED at a public train station. Interviewees were recruited at two time points before and after a four year-long structured regional awareness campaign, which focused on call, compress, shock in a mid-size European city (270,000 inhabitants). Complete BLS was defined as multiple responses for call for help; initiation of chest compressions; and usage of an AED, without mentioning recovery position. Minimal BLS was defined as call for help and initiation of chest compressions. Results: A total of 784 persons were interviewed, 257 at baseline and 527 post-campaign. Confronted with a fictional OHCA, at baseline 8.5% of the interviewees spontaneously mentioned actions for complete BLS and 17.9% post-campaign (p = 0.009). An even larger increase in knowledge was seen in minimal BLS (34.6% vs 60.6%, p < 0.001). Conclusion: After a regional cardiac arrest awareness campaign, we found an increase in knowledge of BLS actions in the lay public. However, our investigation revealed severe gaps in BLS knowledge, possibly resulting in weak first links of the chain of survival.

Data for: Reliability of mechanical ventilation during continuous chest compressions: A crossover study of transport ventilators in a human cadaver model of CPR.

The data presented in this article relate to the research article, "Reliability of mechanical ventilation during continuous chest compressions: a crossover study of transport ventilators in a human cadaver model of CPR" [1]. This article contains raw data of continuous recordings of airflow, airway and esophageal pressure during the whole experiment. Data of mechanical ventilation was obtained under ongoing chest compressions and from repetitive measurements of pressure-volume curves. All signals are presented as raw time series data with a sample rate of 200Hz for flow and 500 Hz for pressure. Additionally, we hereby publish extracted time series recordings of force and compression depth from the used automated chest compression device. Concomitantly, we report tables with time stamps from our laboratory book by which the data can be sequenced into different phases of the study protocol. We also present a dataset of derived volumes which was used for statistical analysis in our research article together with the used exclusion list. The reported dataset can help to understand mechanical properties of Thiel-embalmed cadavers better and compare different models of cardiopulmonary resuscitation (CPR). Future research may use this data to translate our findings from bench to bedside. Our recordings may become useful in developing respiratory monitors for CPR, especially in prototyping and testing algorithms of such devices.

A sliding-window based algorithm to determine the presence of chest compressions from acceleration data.

This publication presents in detail five exemplary cases and the algorithm used in the article (Orlob et al. 2022). Defibrillator records for the five exemplary cases were obtained from the German Resuscitation Registry. They consist of accelerometry, electrocardiogram and capnography time series as well as defibrillation times, energies and impedance when recorded. For these cases, experienced physicians annotated time points of cardiac arrest and return of spontaneous circulation or termination of resuscitation attempts, as well as the beginning and ending of every single chest compression period in consensus, as described in Orlob et al. (2022). Furthermore, an algorithm was developed which reliably detects chest compression periods automatically without the time-consuming process of manual annotation. This algorithm allows for an usage in automatic resuscitation quality assessment, machine learning approaches, and handling of big amounts of data (Orlob et al. 2022).

Chest compression fraction calculation: A new, automated, robust method to identify periods of chest compressions from defibrillator data - Tested in Zoll X Series.

AIM: To introduce and evaluate a new, open-source algorithm to detect chest compression periods automatically by the rhythmic, high amplitude signals from an accelerometer, without processing single chest compression events, and to consecutively calculate the chest compression fraction (CCF). METHODS: A consecutive sample of defibrillator records from the German Resuscitation Registry was obtained and manually annotated in consensus as ground truth. Chest compression periods were determined by different automatic approaches, including the new algorithm. The diagnostic performance of these approaches was assessed. Further, using the different approaches in conjunction with different granularities of manual annotation, several CCF versions were calculated and compared by intraclass correlation coefficient (ICC). RESULTS: 131 defibrillator recordings with a total duration of 5755 minutes were analysed. The new algorithm had a sensitivity of 99.39 (95% CI 99.38, 99.41)% and specificity of 99.17 (95% CI 99.15; 99.18)% to detect chest compressions at any given timepoint. The ICC compared to ground truth was 0.998 for the new algorithm and 0.999 for manual annotation, while the ICC of the proposed algorithm compared to the proprietary software was 0.978. The time required for manual annotation to calculate CCF was reduced by 70.48 (22.55, [94.35, 14.45])%. CONCLUSION: The proposed algorithm reliably detects chest compressions in defibrillator recordings. It can markedly reduce the workload for manual annotation, which may facilitate uniform reporting of measured quality of cardiopulmonary resuscitation. The algorithm is made freely available and may be used in big data analysis and machine learning approaches.

Reliability of mechanical ventilation during continuous chest compressions: a crossover study of transport ventilators in a human cadaver model of CPR.

BACKGROUND: Previous studies have stated that hyperventilation often occurs in cardiopulmonary resuscitation (CPR) mainly due to excessive ventilation frequencies, especially when a manual valve bag is used. Transport ventilators may provide mandatory ventilation with predetermined tidal volumes and without the risk of hyperventilation. Nonetheless, interactions between chest compressions and ventilations are likely to occur. We investigated whether transport ventilators can provide adequate alveolar ventilation during continuous chest compression in adult CPR. METHODS: A three-period crossover study with three common transport ventilators in a cadaver model of CPR was carried out. The three ventilators 'MEDUMAT Standard²', 'Oxylog 3000 plus', and 'Monnal T60' represent three different interventions, providing volume-controlled continuous mandatory ventilation (VC-CMV) via an endotracheal tube with a tidal volume of 6 mL/kg predicted body weight. Proximal airflow was measured, and the net tidal volume was derived for each respiratory cycle. The deviation from the predetermined tidal volume was calculated and analysed. Several mixed linear models were calculated with the cadaver as a random factor and ventilator, height, sex, crossover period and incremental number of each ventilation within the period as covariates to evaluate differences between ventilators. RESULTS: Overall median deviation of net tidal volume from predetermined tidal volume was - 21.2 % (IQR: 19.6, range: [- 87.9 %; 25.8 %]) corresponding to a tidal volume of 4.75 mL/kg predicted body weight (IQR: 1.2, range: [0.7; 7.6]). In a mixed linear model, the ventilator model, the crossover period, and the cadaver's height were significant factors for decreased tidal volume. The estimated effects of tidal volume deviation for each ventilator were - 14.5 % [95 %-CI: -22.5; -6.5] (p = 0.0004) for 'Monnal T60', - 30.6 % [95 %-CI: -38.6; -22.6] (p < 0.0001) for 'Oxylog 3000 plus' and - 31.0 % [95 %-CI: -38.9; -23.0] (p < 0.0001) for 'MEDUMAT Standard²'. CONCLUSIONS: All investigated transport ventilators were able to provide alveolar ventilation even though chest compressions considerably decreased tidal volumes. Our results support the concept of using ventilators to avoid excessive ventilatory rates in CPR. This experimental study suggests that healthcare professionals should carefully monitor actual tidal volumes to recognise the occurrence of hypoventilation during continuous chest compressions.

Adsorption therapy in critically ill with septic shock and acute kidney injury: a retrospective and prospective cohort study.

BACKGROUND: Haemoadsorption has been described as an effective way to control increased pro- and anti-inflammatory mediators ("cytokine storm") in septic shock patients. No prospective or randomised clinical study has yet confirmed these results. However, no study has yet prospectively specifically investigated patients in severe septic shock with sepsis-associated acute kidney injury (SA-AKI). Therefore, we aimed to examine whether haemoadsorption could influence intensive care unit (ICU) and hospital mortality in these patients. Furthermore, we examined the influence of haemoadsorption on length of stay in the ICU and therapeutic support. METHODS: Retrospective control group and prospective intervention group design in a tertiary hospital in central Europe (Germany). Intervention was the implementation of haemoadsorption for patients in septic shock with SA-AKI. 76 patients were included in this analysis. RESULTS: Severity of illness as depicted by APACHE II was higher in patients treated with haemoadsorption. Risk-adjusted ICU mortality rates (O/E ratios) did not differ significantly between the groups (0.80 vs. 0.83). We observed in patients treated with haemoadsorption a shorter LOS and shorter therapeutic support such as catecholamine dependency and duration of RRT. However, in multivariate analysis (logistic regression for mortality, competing risk for LOS), we found no significant differences between the two groups. CONCLUSIONS: The implementation of haemoadsorption for patients in septic shock with acute renal failure did not lead to a reduction in ICU or hospital mortality rates. Despite univariate analysis delivering some evidence for a shorter duration of ICU-related treatments in the haemoadsorption group, these results did not remain significant in multivariate analysis. Trial registration CytoSorb® registry https://clinicaltrials.gov/ct2/show/NCT02312024 . December 9, 2014. DATABASE: https://www.cytosorb-registry.org/ (registration for content acquisition is necessary).

Adult patients' wellbeing and disturbances during early recovery in the post anaesthesia care unit. A cross-sectional study.

OBJECTIVES: Assessment of patients' wellbeing in the post anaesthesia care unit and how much each disturbance influences it. Furthermore, assessment of the incidence of the correlated disturbances and whether there are gender-specific aspects. DESIGN/SETTING: Observational anonymised survey with a validated questionnaire in a university hospital in central Europe. MAIN OUTCOME MEASURES: Incidence rates of wellbeing and disturbances in the post anaesthesia care unit. RESULTS: The patients' most frequently reported early postsurgical disturbances (n = 349) were i) dry mouth (35.4%), ii) pain in the surgical area (12.7%) and iii) hunger (12.2%). Every other disturbance was below 10% (e.g. nausea). Subjective wellbeing was reported by 57.2% of our patients. There were weak correlations between wellbeing and physical discomfort, pain in the surgical area, sleepiness and nausea. The strongest correlation was with physical discomfort. Female patients showed more feelings of cold, nausea and headache. CONCLUSION: Even in hospitals repeatedly certified in pain management, a high percentage of patients still claim early postoperative discomfort. We see the necessity for an increased focus on this topic and the need for investigations regarding patients' perception. The most frequent claims were related to pain in the surgical area and a dry mouth.

Atlanto-occipital dislocation in a patient presenting with out-of-hospital cardiac arrest: a case report and literature review.

BACKGROUND: Atlanto-occipital dislocation is a rare and severe injury of the upper spine associated with a very poor prognosis. CASE PRESENTATION: We report the case of a 59-year-old European man who suffered from out-of-hospital cardiac arrest following a motor vehicle accident. Cardiopulmonary resuscitation was initiated immediately by bystanders and continued by emergency medical services. After 30 minutes of cardiopulmonary resuscitation with a total of five shocks following initial ventricular fibrillation, return of spontaneous circulation was achieved. An electrocardiogram recorded after return of spontaneous circulation at the scene showed signs of myocardial ischemia as a possible cause for the cardiac arrest. No visible signs of injury were found. He was transferred to the regional academic trauma center. Following an extended diagnostic and therapeutic workup in the emergency room, including extended focused assessment with sonography for trauma ultrasound, whole-body computed tomography, and magnetic resonance imaging (of his head and neck), a diagnosis of major trauma (atlanto-occipital dislocation, bilateral serial rip fractures and pneumothoraces, several severe intracranial bleedings, and other injuries) was made. An unfavorable outcome was initially expected due to suspected tetraplegia and his inability to breathe following atlanto-occipital dislocation. Contrary to initial prognostication, after 22 days of intensive care treatment and four surgical interventions (halo fixation, tracheostomy, intracranial pressure probe, chest drains) he was awake and oriented, spontaneously breathing, and moving his arms and legs. Six weeks after the event he was able to walk without aid. After 2 months of clinical treatment he was able to manage all the activities of daily life on his own. It remains unclear, whether cardiac arrest due to a cardiac cause resulted in complete atony of the paravertebral muscles and caused this extremely severe lesion (atlanto-occipital dislocation) or whether cardiac arrest was caused by apnea due the paraplegia following the spinal injury of the trauma. CONCLUSIONS: A plausible cause for the trauma was myocardial infarction which led to the car accident and the major trauma in relation to the obviously minor trauma mechanism. With this case report we aim to familiarize clinicians with the mechanism of injury that will assist in the diagnosis of atlanto-occipital dislocation. Furthermore, we seek to emphasize that patients presenting with electrocardiographic signs of myocardial ischemia after high-energy trauma should primarily be transported to a trauma facility in a percutaneous coronary intervention-capable center rather than the catheterization laboratory directly.