Cardiopulmonary resuscitation for cardiac arrest: the importance of uninterrupted chest compressions in cardiac arrest resuscitation

Novel Pharyngeal Oxygen Delivery Device Provides Superior Oxygenation during Simulated Cardiopulmonary Resuscitation

INTRODUCTION

Passive oxygenation with non-rebreather face mask (NRFM) has been used during cardiac arrest as an alternative to positive pressure ventilation (PPV) with bag-valve-mask (BVM) to minimize chest compression disruptions. A dual-channel pharyngeal oxygen delivery device (PODD) was created to open obstructed upper airways and provide oxygen at the glottic opening. It was hypothesized for this study that the PODD can deliver oxygen as efficiently as BVM or NRFM and oropharyngeal airway (OPA) in a cardiopulmonary resuscitation (CPR) manikin model.

METHODS

Oxygen concentration was measured in test lungs within a resuscitation manikin. These lungs were modified to mimic physiologic volumes, expansion, collapse, and recoil. Automated compressions were administered. Five trials were performed for each of five arms: (1) CPR with 30:2 compression-to-ventilation ratio using BVM with 15 liters per minute (LPM) oxygen; continuous compressions with passive oxygenation using (2) NRFM and OPA with 15 LPM oxygen, (3) PODD with 10 LPM oxygen, (4) PODD with 15 LPM oxygen; and (5) control arm with compressions only.

RESULTS

Mean peak oxygen concentrations were: (1) 30:2 CPR with BVM 49.3% (SD = 2.6%); (2) NRFM 47.7% (SD = 0.2%); (3) PODD with 10 LPM oxygen 52.3% (SD = 0.4%); (4) PODD with 15 LPM oxygen 62.7% (SD = 0.3%); and (5) control 21% (SD = 0%). Oxygen concentrations rose rapidly and remained steady with passive oxygenation, unlike 30:2 CPR with BVM, which rose after each ventilation and decreased until the next ventilation cycle (sawtooth pattern, mean concentration 40% [SD = 3%]).

CONCLUSIONS

Continuous compressions and passive oxygenation with the PODD resulted in higher lung oxygen concentrations than NRFM and BVM while minimizing CPR interruptions in a manikin model.

Airway management and ventilation techniques in resuscitation during advanced life support: an update

For many years, ventilation has been an essential part of advanced life support (ALS) in cardiopulmonary resuscitation (CPR). Nevertheless, there is little evidence about the best method of ventilation during resuscitation for both out-of-hospital cardiac arrest (OHCA) and inhospital cardiac arrest (IHCA) patients. Effective ventilation is one of the two main keys to successful resuscitation. In this context, the question always arises as to which airway management, along with which ventilation mode, constitutes the best strategy. Conventional ventilation modes are not designed for cardiac arrest and show important limitations that must be considered when used in CPR. Manual ventilation without the use of an automated transport ventilator (ATV) could be shown to be uncontrolled in applied volumes and pressures and should be avoided. Mechanical ventilation with an ATV is therefore superior to manual ventilation, but both volume- and pressure-controlled ventilation modes are significantly influenced by chest compressions. With the newly designed chest compression synchronized ventilation (CCSV), a special ventilation mode for resuscitation is available. Further research should be conducted to obtain more evidence of the effect of ventilation during CPR on outcomes following OHCA and not only about how to secure the airway for ventilation during CPR.

Assessing the quality of chest compressions with a DIY low-cost manikin (LoCoMan) versus a standard manikin: a quasi-experimental study in primary education

Extending the access to cardiopulmonary resuscitation (CPR) training to a wider public is an important step in increasing survivability of out-of-hospital cardiac arrest. However, often price and maintenance of CPR manikins are barriers that prevent training at schools. This study aims to evaluate the learning of hands-only (HO) CPR by practicing with a low-cost manikin (LoCoMan) with visual qualitative feedback and to compare the results with the skills acquired by practice on a conventional manikin. A quasi-experimental study with 193 schoolchildren (10 to 12 years old) who were allocated to two groups: the LoCoMan group was taught via an integrative approach (science combined with physical education (PE)) and practiced on a handmade manikin, and a control group practiced in a traditional setting with a commercial manikin (Resusci Junior, Laerdal, Norway). All participants practiced for 1 hands-on skill session before performing a post-test on an instrumented CPR manikin. The outcomes including HO-CPR performance variables were compared between groups. The LoCoMan and control groups both achieved acceptable percentage of HO-CPR quality (57% and 71%, p = 0.004). Among 6th-graders, there were no significant differences in HO-CPR quality between LoCoMan 68% and control 71%, p = 0.66. The control group achieved better chest compression depth while the LoCoMan group showed more compressions with adequate chest recoil.     Conclusion: Schoolchildren are able to build and use a low-cost manikin with visual feedback. The integrative learning approach used in this study may be a feasible alternative methodology for training and learning HO-CPR in schools when commercial manikins are not available. What is Known: • Access to CPR training should be universal and independent of age, location, financial means, or access to qualified instructors. • Scientific societies promote the implementation of CPR in schools, so that teachers and schoolchildren can play a multiplier role in their environment, but the gap in CPR learning is related to cultural, economic factors or access to resources and materials. What is New: • LoCoMan may be a useful device for teaching and learning CPR in schoolchildren from the age of 10 and upwards. • LOCOMAN shows that it is feasible and possible to build a low-cost manikin (about €5 in the European Region) and to integrate it into an integrative educational project, and outlines how this could be done. this approach can be an incentive for teachers to attempt teaching CPR, but also for education outside the formal environment.

Ischemic Post-Conditioning in a Rat Model of Asphyxial Cardiac Arrest

BACKGROUND

Ischemic post-conditioning (IPoC) has been shown to improve outcomes in limited pre-clinical models. As down-time is often unknown, this technique needs to be investigated over a range of scenarios. As this tool limits reperfusion injury, there may be limited benefit or even harm after short arrest and limited ischemia-reperfusion injury.

METHODS

Eighteen male Wistar rats underwent 7 min of asphyxial arrest. Animals randomized to IPoC received a 20 s pause followed by 20 s of compressions, repeated four times, initiated 40 s into cardiopulmonary resuscitation. If return of spontaneous circulation (ROSC) was achieved, epinephrine was titrated to mean arterial pressure (MAP) of 70 mmHg. Data were analyzed using t-test or Mann-Whitney test. Significance set at p ≤ 0.05.

RESULTS

The rate of ROSC was equivalent in both groups, 88%. There was no statistically significant difference in time to ROSC, epinephrine required post ROSC, carotid flow, or peak lactate at any timepoint. There was a significantly elevated MAP with IPoC, 90.7 mmHg (SD 13.9), as compared to standard CPR, 76.7 mmHg (8.5), 2 h after ROSC, p = 0.03.

CONCLUSIONS

IPoC demonstrated no harm in a model of short arrest using a new arrest etiology for CPR based IPoC intervention in a rat model.

Point-of-Care Ultrasound (POCUS) in Adult Cardiac Arrest: Clinical Review

Point-of-Care Ultrasound (POCUS) is a rapid and valuable diagnostic tool available in emergency and intensive care units. In the context of cardiac arrest, POCUS application can help assess cardiac activity, identify causes of arrest that could be reversible (such as pericardial effusion or pneumothorax), guide interventions like central line placement or pericardiocentesis, and provide real-time feedback on the effectiveness of resuscitation efforts, among other critical applications. Its use, in addition to cardiovascular life support maneuvers, is advocated by all resuscitation guidelines. The purpose of this narrative review is to summarize the key applications of POCUS in cardiac arrest, highlighting, among others, its prognostic, diagnostic, and forensic potential. We conducted an extensive literature review utilizing PubMed by employing key search terms regarding ultrasound and its use in cardiac arrest. Apart from its numerous advantages, its limitations and challenges such as the potential for interruption of chest compressions during image acquisition and operator proficiency should be considered as well and are discussed herein.

Efficacy of Cardiopulmonary Resuscitation Using Automatic Compression-Defibrillation Apparatus: An Animal Study and A Manikin-Based Simulation Study

BACKGROUND

Chest compression and defibrillation are essential components of cardiac arrest treatment. Mechanical chest compression devices (MCCD) and automated external defibrillators (AED) are used separately in clinical practice. We developed an automated compression-defibrillation apparatus (ACDA) that performs mechanical chest compression and automated defibrillation. We investigated the performance of cardiopulmonary resuscitation (CPR) with automatic CPR (A-CPR) compared to that with MCCD and AED (conventional CPR: C-CPR).

METHODS

Pigs were randomized into A-CPR or C-CPR groups: The A-CPR group received CPR+ACDA, and the C-CPR group received CPR+MCCD+AED. Hemodynamic parameters, outcomes, and time variables were measured. During a simulation study, healthcare providers performed a basic life support scenario for manikins with an ACDA, MCCD, and AED, and time variables and chest compression parameters were measured.

RESULTS

The animals showed no significant in hemodynamic effects, including aortic pressures, coronary perfusion pressure, carotid blood flow, and end-tidal CO2, and resuscitation outcomes between the two groups. In both animal and simulation studies, the time to defibrillation, time to chest compression, and hands-off time were significantly shorter in the A-CPR group than those in the C-CPR group.

CONCLUSIONS

CPR using ACDA showed similar hemodynamic effects and resuscitation outcomes as CPR using AED and MCCD separately, with the advantages of a reduction in the time to compression, time to defibrillation, and hands-off time.

Videolaryngoscopy versus direct laryngoscopy for endotracheal intubation of cardiac arrest patients in hospital: A systematic literature review

Aims

Airway management during cardiopulmonary resuscitation may involve endotracheal intubation complicated by associated difficulties. Videolaryngoscopy may help to ease these difficulties and increase success rates by removing the need to achieve a direct line of sight required by standard direct laryngoscopy. This literature review aims to establish if there is an overall benefit in using videolaryngoscopy over direct laryngoscopy when intubating patients during cardiac arrest in the non-theatre hospital environment.

Methods

The review was registered on PROSPERO (record ID 329987). A systematic search was conducted of EMBASE, MEDLINE, CINAHL and Web of Science for literature comparing the use of videolaryngoscopy to direct laryngoscopy during intubation of cardiac arrest patients in hospital up until 4th May 2022. The Cochrane Central Register of Controlled Trials (CENTRAL) database was accessed, and reference lists of relevant systematic reviews were analysed for further papers. Forward and backward citation tracking was carried out of the shortlisted papers to hand-search for any further relevant studies. Papers were included in the review if they used adult patients, the patients were intubated during cardiac arrest in hospital and if the papers were in English language or had an accessible translation. Papers were excluded if patients were intubated not during cardiac arrest, the studies were based outside of a hospital setting or in the operating theatre, the patients were paediatric or if the study used a simulation or manikin. The Critical Appraisal Skills Programme checklists were used to assess risk of bias. Odds ratios, confidence intervals and probability values were used to synthesise results.

Results

Six studies were identified that collectively analysed 4525 patients who were intubated during cardiac arrest in the non-theatre hospital environment; five studies were observational and one a randomised controlled trial. Most of the studies being observational in nature led to a significant bias in their methodology which is a limitation to this review. The studies all measured first pass success rate as the primary outcome. First pass success rate only improved with videolaryngoscopy compared to direct laryngoscopy when the intubator was a less experienced clinician. Videolaryngoscopy also reduced some endotracheal intubation related complications and improved glottic visualisation when compared to direct laryngoscopy.

Conclusion

The limited data suggests that use of videolaryngoscopy improved first pass success rates compared to direct laryngoscopy when the clinician was less experienced.

Monitoring cardiopulmonary resuscitation quality in emergency departments: a national survey in China on current knowledge, attitudes, and practices

BACKGROUND

To investigate current knowledge, attitudes, and practices for CPR quality control among emergency physicians in Chinese tertiary hospitals.

METHODS

Anonymous questionnaires were distributed to physicians in 75 tertiary hospitals in China between January and July 2018.

RESULTS

A total of 1405 respondents answered the survey without obvious logical errors. Only 54.4% respondents knew all criteria of high-quality CPR. A total of 91.0% of respondents considered CPR quality monitoring should be used, 72.4% knew the objective method for monitoring, and 63.2% always/often monitored CPR quality during actual resuscitation. The main problems during CPR were related to chest compression: low quality due to fatigue (67.3%), inappropriate depth (57.3%) and rate (54.1%). The use of recommended monitoring methods was reported as follows, ETCO2 was 42.7%, audio-visual feedback devices was 10.1%, coronary perfusion pressure was 17.9%, and invasive arterial pressure was 31.1%. A total of 96.3% of respondents considered it necessary to participate in regular CPR retraining, but 21.4% did not receive any retraining. The ideal retraining interval was considered to be 3 to 6 months, but the actual interval was 6 to 12 months. Only 49.7% of respondents reported that feedback devices were always/often used in CPR training.

CONCLUSION

Chinese emergency physicians were very concerned about CPR quality, but they did not fully understand the high-quality criteria and their impact on prognosis. CPR quality monitoring was not a routine procedure during actual resuscitation. The methods recommended in guidelines were rarely used in practice. Many physicians had not received retraining or received retraining at long intervals. Feedback devices were not commonly used in CPR training.

Inverse Association Between Bystander Use of Audiovisual Feedback From an Automated External Defibrillator and Return of Spontaneous Circulation

Background

Treatment with an automated external defibrillator (AED) improves outcome in out‐of‐hospital cardiac arrest (OHCA). Audiovisual feedback from an AED may assist bystanders achieve higher quality cardiopulmonary resuscitation. However, the association between audiovisual feedback and clinical outcomes is not well assessed in real‐life OHCA. The aim of this study was to assess the association between audiovisual feedback from an AED used in bystander resuscitation with rates of return of spontaneous circulation (ROSC) and 30‐day survival in a real‐life cohort of patients with OHCA.

Methods and Results

We included 325 patients treated with bystander AED use before arrival of emergency medical services during 2016 to 2019 from the Capital Region of Denmark. Patients were divided into a “feedback” and a “nonfeedback” group, depending on presence of audiovisual feedback from the AED. Audiovisual feedback was defined as voice prompts with continuous feedback to ongoing resuscitation. Rates of ROSC upon hospital admission and 30‐day survival were assessed, and univariate and multivariable models were applied to decide the association to audiovisual feedback. Multivariable models were adjusted for sex, age, primary heart rhythm, and location of OHCA. A total of 155 (48%) patients had a bystander AED applied with audiovisual feedback and 170 (52%) without audiovisual feedback. A lower rate of ROSC was found in the feedback group compared with the nonfeedback group (33% [n=51] versus 45% [n=76]; P =0.03). No association was observed between AV feedback and 30‐day survival (feedback=27% [n=42] and nonfeedback=31% [n=53]; P =0.49). In the unadjusted logistic regression model, audiovisual feedback was associated with a decreased chance of ROSC (odds ratio, 0.61; 95% CI, 0.38–0.95; P =0.03), which remained significant after adjusted analysis (odds ratio, 0.53; 95% CI, 0.29–0.97; P =0.04), whereas we found no significant association between audiovisual feedback and 30‐day survival in the unadjusted and adjusted analyses.

Conclusions

Audiovisual feedback from an AED used by bystanders was associated with a lower chance of ROSC at hospital admission, but we found no significant difference in 30‐day survival. Focus on early and correct bystander cardiopulmonary resuscitation and AED use remain key for OHCA survival.

Manual Palpation vs. Femoral Arterial Doppler Ultrasound for Comparison of Pulse Check Time During Cardiopulmonary Resuscitation in the Emergency Department: A Pilot Study

BACKGROUND

Manual palpation (MP) is frequently employed for pulse checks, but studies have shown that trained medical personnel have difficulty accurately identifying pulselessness or return of spontaneous circulation (ROSC) using MP. Any delays in identifying pulselessness can lead to significant delays in starting or resuming high-quality chest compressions.

OBJECTIVES

This study explored whether femoral arterial Doppler ultrasound (FADU) decreases pulse check duration during cardiopulmonary resuscitation (CPR) compared with MP among patients in the emergency department (ED) receiving CPR directed by emergency medicine physicians who had received minimal additional didactic ultrasound training.

METHODS

We performed a prospective observational cohort study from October 2018 to May 2019 at an urban community ED. Using convenience sampling, we enrolled patients arriving at our ED or who decompensated during their ED stay and received CPR. For continuous data, median (interquartile range [IQR]) were calculated, and medians were compared using Kruskal-Wallis test.

RESULTS

Fifty-two eligible patients were enrolled and 135 pulse checks via MP and 35 via FADU were recorded. MP observations had a median (IQR) of 11.00 (7.36-15.48) s, whereas FADU had a median (IQR) of 8.98 (5.45-13.85) s. There was a difference between the two medians of 2.02 s (p = 0.05).

CONCLUSIONS

In this study, the use of FADU was superior to MP in achieving shorter pulse check times. Further research is needed to confirm the accuracy of FADU for identifying ROSC as well as to determine whether FADU can improve clinical outcomes.

Trends in In-Hospital Advanced Management and Survival of Out-of-Hospital Cardiac Arrest Among Adults From 2013 to 2017 - A Multicenter, Prospective Registry in Osaka, Japan

BACKGROUND

The aim of our study was to investigate in detail the temporal trends in in-hospital characteristics, actual management, and survival, including neurological status, among adult out-of-hospital cardiac arrest (OHCA) patients in recent years.

METHODS AND RESULTS

From the prospective database of the Comprehensive Registry of Intensive Care for OHCA Survival (CRITICAL) study in Osaka, Japan, we enrolled all OHCA patients aged ≥18 years for whom resuscitation was attempted, and who were transported to participating hospitals between the years 2013 and 2017. The primary outcome measure was 1-month survival with favorable neurological outcome after OHCA. Temporal trends in in-hospital management and favorable neurological outcome among adult OHCA patients were assessed. Of the 11,924 patients in the database, we included a total of 10,228 adult patients from 16 hospitals. As for in-hospital advanced treatments, extracorporeal cardiopulmonary resuscitation (ECPR) use increased from 2.4% in 2013 to 4.3% in 2017 (P for trend <0.001). However, the proportion of adult OHCA patients with favorable neurological outcome did not change during the study period (from 5.7% in 2013 to 4.4% in 2017, adjusted odds ratio (OR) for 1-year increment: 0.98 (95% confidence interval: 0.94-1.23)).

CONCLUSIONS

In this target population, in-hospital management such as ECPR increased slightly between 2013 and 2017, but 1-month survival with favorable neurological outcome after adult OHCA did not improve significantly.

Impact of structured basic life-support course on nurses' cardiopulmonary resuscitation knowledge and skills: Experience of a paediatric department in low-resource country

INTRODUCTION

The study aimed to assess the impact of a modified paediatric basic life support (BLS) training on paediatric nurses' knowledge and skills in the main tertiary level public hospital in Rwanda.

METHODS

A prospective, before-and-after educational intervention study was performed. Nurses working in the paediatric department at Centre Hospitalier Universitaire de Kigali (CHUK) were enrolled after consenting to the study. A modified BLS training was administered using didactic lectures, videos, case discussions, and simulations. Knowledge and skills were assessed before, immediately and six months after the training, using the American Heart Association (AHA) multiple-choice questions test and simulation scenarios. Ethical approval from the hospital's investigational review board was obtained before the start of the study.

RESULTS

Fifty-seven nurses working in paediatric department were included in the study, most with advanced nursing degrees. At baseline, only 3.5% scored above 80% on the knowledge test and none were able to perform high-quality one-rescuer CPR. Knowledge and high-quality one-rescuer CPR skills improved significantly immediately after the training, with 63.2% scoring above 80% and 63.2% capable of performing high-quality one-rescuer CPR (p < 0.01). Six months later, only 45.6% scored above 80% and 15.8% were capable of performing high-quality one-rescuer CPR (p < 0.01). Some skills, such as delivering breaths using bag-mask device, showed better retention.

CONCLUSION

In the paediatric department of the main public tertiary care hospital in Rwanda, nurses' baseline knowledge and skills in providing BLS was poor but can increase with focused BLS training. Due to the decline in knowledge and skills over six months, the use of debriefing and focused trainings following resuscitation events and improved implementation of yearly departmental refresher courses are recommended.

Cardiopulmonary Resuscitation With Mechanical Chest Compression Device During Percutaneous Coronary Intervention. A Case Report

Sudden cardiac death is a leading cause of death worldwide, whereby myocardial infarction is considered the most frequent underlying condition. Percutaneous coronary intervention (PCI) is an important component of post-resuscitation care, while uninterrupted high-quality chest compressions are key determinants in cardiopulmonary resuscitation (CPR). In our paper, we evaluate a case of a female patient who suffered aborted cardiac arrest due to myocardial infarction. The ambulance crew providing prehospital care for sudden cardiac arrest used a mechanical chest compression device during advanced CPR, which enabled them to deliver ongoing resuscitation during transfer to the PCI laboratory located 20 km away from the scene. Mechanical chest compressions were continued during the primary coronary intervention. The resuscitation, carried out for 2 h and 35 min, and the coronary intervention were successful, as evidenced by the return of spontaneous circulation and by the fact that, after a short rehabilitation, the patient was discharged home with a favorable neurological outcome. Our case can serve as an example for the effective and safe use of a mechanical compression device during primary coronary intervention.

Feline cardiopulmonary resuscitation: Getting the most out of all nine lives

PRACTICAL RELEVANCE

Cardiopulmonary arrest (CPA) can occur in any veterinary or animal care setting and is a particular risk in scenarios involving ill, injured or anesthetized patients. Education of all staff on the prevention and recognition of CPA, as well as the performance of cardiopulmonary resuscitation (CPR), is vital to influencing outcome.

EVIDENCE BASE

While there is a plethora of information regarding CPA and CPR in human medicine, there are comparably few studies in the veterinary literature. Many of the current veterinary guidelines are extrapolated from human medicine or studies based on animal models. Ongoing work is needed to tailor guidelines and recommendations to our domestic feline (and canine) patients in a clinical setting.

AIM

The aim of this article, which is intended for veterinarians in all areas of small animal practice, is to provide an evidence-based review of CPA and CPR in feline patients. The authors have drawn heavily on detailed recommendations published by the Reassessment Campaign on Veterinary Resuscitation (RECOVER) initiative - one of the few resources specific to the veterinary clinical setting - as well as reviewing the available peer-reviewed literature studies, in constructing this article. Among the topics discussed are recognizing and preventing CPA, staff training and clinic preparedness, basic life support and advanced life support interventions, and appropriate post-cardiac arrest care.

State-of-the-Art Review-Endovascular Resuscitation

ABSTRACT

The emerging concept of endovascular resuscitation applies catheter-based techniques in the management of patients in shock to manipulate physiology, optimize hemodynamics, and bridge to definitive care. These interventions hope to address an unmet need in the care of severely injured patients, or those with refractory non-traumatic cardiac arrest, who were previously deemed non-survivable. These evolving techniques include Resuscitative Endovascular Balloon Occlusion of Aorta, Selective Aortic Arch Perfusion, and Extracorporeal Membrane Oxygenation and there is a growing literature base behind them. This review presents the up-to-date techniques and interventions, along with their application, evidence base, and controversy within the new era of endovascular resuscitation.

Volumetric Capnography Monitoring and Effects of Epinephrine on Volume of Carbon Dioxide Elimination during Resuscitation after Cardiac Arrest in a Swine Pediatric Ventricular Fibrillatory Arrest

The aim of this study was to examine the use of volumetric capnography monitoring to assess cardiopulmonary resuscitation (CPR) effectiveness by correlating it with cardiac output (CO), and to evaluate the effect of epinephrine boluses on both end-tidal carbon dioxide (EtCO 2 ) and the volume of CO 2 elimination (VCO 2 ) in a swine ventricular fibrillation cardiac arrest model. Planned secondary analysis of data collected to investigate the use of noninvasive monitors in a pediatric swine ventricular fibrillation cardiac arrest model was performed. Twenty-eight ventricular fibrillatory arrests with open cardiac massage were conducted. During CPR, EtCO 2 and VCO 2 had strong correlation with CO, measured as a percentage of baseline pulmonary blood flow, with correlation coefficients of 0.83 ( p  < 0.001) and 0.53 ( p  = 0.018), respectively. However, both EtCO 2 and VCO 2 had weak and nonsignificant correlation with diastolic blood pressure during CPR 0.30 ( p  = 0.484) (95% confidence interval [CI], -0.51-0.83) and 0.25 ( p  = 0.566) (95% CI, -0.55-0.81), respectively. EtCO 2 and VCO 2 increased significantly after the first epinephrine bolus without significant change in CO. The correlations between EtCO 2 and VCO 2 and CO were weak 0.20 ( p  = 0.646) (95% CI, -0.59-0.79), and 0.27 ( p  = 0.543) (95% CI, -0.54-0.82) following epinephrine boluses. Continuous EtCO 2 and VCO 2 monitoring are potentially useful metrics to ensure effective CPR. However, transient epinephrine administration by boluses might confound the use of EtCO 2 and VCO 2 to guide chest compression.

The effect of high-dose intramuscular epinephrine on the recovery of spontaneous circulation in an asphyxia-induced cardiac arrest rat model

BACKGROUND

Obtaining vascular access can be challenging during resuscitation following cardiac arrest, and it is particularly difficult and time-consuming in paediatric patients. We aimed to compare the efficacy of high-dose intramuscular (IM) versus intravascular (IV) epinephrine administration with regard to the return of spontaneous circulation (ROSC) in an asphyxia-induced cardiac arrest rat model.

METHODS

Forty-five male Sprague-Dawley rats were used for these experiments. Cardiac arrest was induced by asphyxia, and defined as a decline in mean arterial pressure (MAP) to 20 mmHg. After asphyxia-induced cardiac arrest, the rats were randomly allocated into one of 3 groups (control saline group, IV epinephrine group, and IM epinephrine group). After 540 s of cardiac arrest, cardiopulmonary resuscitation was performed, and IV saline (0.01 cc/kg), IV (0.01 mg/kg, 1:100,000) epinephrine or IM (0.05 mg/kg, 1:100,000) epinephrine was administered. ROSC was defined as the achievement of an MAP above 40 mmHg for more than 1 minute. Rates of ROSC, haemodynamics, and arterial blood gas analysis were serially observed.

RESULTS

The ROSC rate (61.5%) of the IM epinephrine group was less than that in the IV epinephrine group (100%) but was higher than that of the control saline group (15.4%) (log-rank test). There were no differences in MAP between the two groups, but HR in the IM epinephrine group (beta coefficient = 1.02) decreased to a lesser extent than that in the IV epinephrine group with time.

CONCLUSIONS

IM epinephrine induced better ROSC rates compared to the control saline group in asphyxia-induced cardiac arrest, but not compared to IV epinephrine. The IM route of epinephrine administration may be a promising option in an asphyxia-induced cardiac arrest.

Impact of the modified SESAME ultrasound protocol implementation on patients with cardiac arrest in the emergency department

INTRODUCTION

Point-of-care (POC) ultrasound protocols are commonly used for the initial management of patients with cardiac arrest in the emergency department (ED). However, there is little published evidence regarding any mortality benefit. We compared and studied the effect of implementation of the modified SESAME protocol in terms of clinical outcomes and resuscitation management.

METHODS

This was a single-center retrospective observational study. We conducted a pre- and post-intervention study to evaluate changes in patient outcomes and management after educating emergency medicine residents and the faculty about the modified SESAME protocol. The pre-intervention period lasted from March 2018 to February 2019, and the post-intervention period lasted from May 2019 to April 2020. The modified SESAME protocol education was initiated in March 2019. Multivariate logistic regression analyses were performed to examine the associations between independent variables and outcomes.

RESULTS

A total of 334 patients were included in this study during a 24-month period. We found no significant differences between the two groups for the primary outcome of survival to hospital admission (pre-intervention group 28.9% versus post-intervention group 28.6%; P = 0.751), survival to hospital discharge (12.1% vs. 12.4%; P = 0.806), and good neurologic outcome at discharge (6.0% vs. 8.1%; P = 0.509). The proportion of resuscitation procedures of thrombolysis, emergency transfusion, tube thoracotomy, and pericardiocentesis during resuscitation increased from 0.6% in the pre-intervention period to 4.9% in the post-intervention period (P = 0.016).

CONCLUSION

We did not discover any significant survival benefits associated with the implementation of the modified SESAME protocol; however, early diagnosis of specific pathologies (pericardial effusion, possible pulmonary embolism, tension pneumothorax, and hypovolemia) and accordingly a direct increase in the resuscitation management were seen in this study. Future studies with larger sample sizes are required to examine the clinical outcomes as well as to identify the most effective POC ultrasonography protocols for non-traumatic cardiac arrests.

Transesophageal echocardiography in patients with cardiac arrest: from high-quality chest compression to effective resuscitation

BACKGROUND

Survival after cardiac arrest depends on prompt and effective cardiopulmonary resuscitation (CPR). Transesophageal echocardiography (TEE) can be applied to evaluate the effectiveness of chest compression-decompression maneuvers in the setting of cardiac arrest undergoing CPR. The efficacy of chest compression can be continuously assessed by TEE that can improve the effectiveness of CPR guiding the rescuer to optimize or correct chest compression and decompression by directly examining the movements of the cardiac walls and valve leaflets.

PURPOSE

The review describes how to perform TEE in the emergency setting of cardiopulmonary arrest, its advantages, and limitations, and ultimately propose an echo-guided approach to CPR.

Cardiopulmonary resuscitation (CPR) during spaceflight - a guideline for CPR in microgravity from the German Society of Aerospace Medicine (DGLRM) and the European Society of Aerospace Medicine Space Medicine Group (ESAM-SMG)

BACKGROUND

With the "Artemis"-mission mankind will return to the Moon by 2024. Prolonged periods in space will not only present physical and psychological challenges to the astronauts, but also pose risks concerning the medical treatment capabilities of the crew. So far, no guideline exists for the treatment of severe medical emergencies in microgravity. We, as a international group of researchers related to the field of aerospace medicine and critical care, took on the challenge and developed a an evidence-based guideline for the arguably most severe medical emergency - cardiac arrest.

METHODS

After the creation of said international group, PICO questions regarding the topic cardiopulmonary resuscitation in microgravity were developed to guide the systematic literature research. Afterwards a precise search strategy was compiled which was then applied to "MEDLINE". Four thousand one hundred sixty-five findings were retrieved and consecutively screened by at least 2 reviewers. This led to 88 original publications that were acquired in full-text version and then critically appraised using the GRADE methodology. Those studies formed to basis for the guideline recommendations that were designed by at least 2 experts on the given field. Afterwards those recommendations were subject to a consensus finding process according to the DELPHI-methodology.

RESULTS

We recommend a differentiated approach to CPR in microgravity with a division into basic life support (BLS) and advanced life support (ALS) similar to the Earth-based guidelines. In immediate BLS, the chest compression method of choice is the Evetts-Russomano method (ER), whereas in an ALS scenario, with the patient being restrained on the Crew Medical Restraint System, the handstand method (HS) should be applied. Airway management should only be performed if at least two rescuers are present and the patient has been restrained. A supraglottic airway device should be used for airway management where crew members untrained in tracheal intubation (TI) are involved.

DISCUSSION

CPR in microgravity is feasible and should be applied according to the Earth-based guidelines of the AHA/ERC in relation to fundamental statements, like urgent recognition and action, focus on high-quality chest compressions, compression depth and compression-ventilation ratio. However, the special circumstances presented by microgravity and spaceflight must be considered concerning central points such as rescuer position and methods for the performance of chest compressions, airway management and defibrillation.

Current evidence of survival benefit between chest-compression only versus standard cardiopulmonary resuscitation in out-of-hospital cardiac arrest : Updated systematic review and meta-analysis of randomized controlled trials with trial sequential analysis

BACKGROUND

Evidence to support a better cardiopulmonary resuscitation method between standard vs. continuous chest compression (STD-CPR vs. CCC-CPR) is lacking.

MATERIALS AND METHODS

Our systematic review followed PRISMA guidelines. We searched PubMed, ScienceDirect, EBSCOhost, and ProQuest database from 1985 to 26 September 2019 restricted to randomized controlled trial, human study, and English articles. Quality assessment of between-study heterogeneity and a trial sequential analysis (TSA) were conducted. We estimated overall significance with 80% power and adjusted Z values thresholds using O'Brien-Fleming α‑spending function. Required information size with 21% relative risk using the estimation between-group incidences provided from the median rate across trials was determined. Inconclusive TSA result will lead to size estimation of future RCT. Quality of evidence was analyzed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) Handbook and TSA.

RESULTS

Based on three trials in OHCA with dispatcher-guided and bystander-initiated CPR, our meta-analysis favors CCC-CPR for survival to hospital discharge, compared to STD-CPR (RR [Risk Ratio] = 1.21[1.01-1.46], 95% CI, p = 0.68, I² = 0). However, current meta-analyses with 3031 patients appeared to be inconclusive. There is a significant risk of type 1 error and therefore, results are potentially false positive. It is estimated that a minimal of 4331 patients needed to deem a conclusive result and a total of 5894 patients with similar risk profile required to stabilize statistic results in future trials. Quality of evidence is downgraded to moderate due to serious imprecision based on TSA.

CONCLUSION

Based on these analyses, evidence is inadequate to conclude the superiority of one CPR method over the other. Further trials with larger numbers of patients are needed to deem a conclusive and stable meta-analysis.

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

Factors associated with return of spontaneous circulation after out-of-hospital cardiac arrest in Poland: a one-year retrospective study

Background

Out-of-hospital cardiac arrest (OHCA) is a common reason for calls for intervention by emergency medical teams (EMTs) in Poland. Regardless of the mechanism, OHCA is a state in which the chance of survival is dependent on rapid action from bystanders and responding health professionals in emergency medical services (EMS). We aimed to identify factors associated with return of spontaneous circulation (ROSC).

Methods

The medical records of 2137 EMS responses to OHCA in the city of Wroclaw, Poland between July 2017 and June 2018 were analyzed.

Results

The OHCA incidence rate for the year studied was 102 cases per 100,000 inhabitants. EMS were called to 2317 OHCA events of which 1167 (50.4%) did not have resuscitation attempted on EMS arrival. The difference between the number of successful and failed cardiopulmonary resuscitations (CPRs) was statistically significant (p < 0.001). Of 1150 patients in whom resuscitation was attempted, ROSC was achieved in 250 (27.8%). Rate of ROSC was significantly higher when CPR was initiated by bystanders (p < 0.001). Patients presenting with asystole or pulseless electrical activity (PEA) had a higher risk of CPR failure (86%) than those with ventricular fibrillation/ventricular tachycardia (VF/VT). Patients with VF/VT had a higher chance of ROSC (OR 2.68, 1.86–3.85) than those with asystole (p < 0.001). The chance of ROSC was 1.78 times higher when the event occurred in a public place (p < 0.001).

Conclusions

The factors associated with ROSC were occurrence in a public place, CPR initiation by witnesses, and presence of a shockable rhythm. Gender, age, and the type of EMT did not influence ROSC. Low bystander CPR rates reinforce the need for further efforts to train the public in CPR.

The use of prefilled adrenaline syringes improves cardiopulmonary resuscitation quality-high-fidelity simulator-based study

BACKGROUND

In some countries, adrenaline is available only in glass ampoules. However, simplification of cardiopulmonary resuscitation (CPR) by introducing prefilled syringes may ensure more efficient CPR. The aim of this study was to investigate the impact of different forms of adrenaline on the CPR quality.

METHODS

In a randomized cross-examination simulation study, 100 two-person paramedical teams took part in two 10-minute scenarios of sudden cardiac arrest (SCA) in a pulseless electrical activity mechanism (PEA). In the first scenario the set of medicines contained glass ampoules (group ST) with adrenaline, in the second prefilled syringes (group AMPS). The parameters of the CPR quality [correct number and depth of chest compressions (CC), no flow time, chest recoil, time to apply supraglottic airways device (SAD)] were compared.

RESULTS

In group AMPS the first dose of adrenaline was administered after 114.2±28.3 seconds after the initiation of CPR whereas after 178.1±62.6 seconds in group ST (P<0.001). Chest compression fraction (CCF) was higher (81.8%±6.1%) in group AMPS than in group ST (71.2%±7.5%). Paramedics performed CC at better frequency, to a preferred depth and in an appropriate place in group AMPS. Faster decision to apply SAD (131.7±34.0 s in group AMPS and 220.3±81.5 s in group ST) ensured faster achievement of airway patency in this group (181.5±48.7 vs. 271.2±101.5 s).

CONCLUSIONS

Prefilled syringes with crucial drugs during CPR may significantly improve the quality of CPR performed by two-person teams.

A Pilot Study of CPR Quality Comparing an Augmented Reality Application vs. a Standard Audio-Visual Feedback Manikin

Background: Guidelines-based cardiopulmonary resuscitation (CPR) during in-hospital cardiac arrest is a significant predictor of survival, yet the quality of healthcare provider (HCP) CPR (e.g., nurses, physicians etc.) has been shown to be poor. Studies have found that providing HCPs with simulated CPR refresher trainings can improve their CPR quality, however, no studies have compared the use of an augmented reality (AR) CPR refresher training with a standard audio-visual (AV) feedback manikin to improve HCP training.

Objectives: In our pilot study, HCPs were randomized to a refresher CPR simulation training with either our AR CPR training application (CPReality) or a standard AV feedback manikin. All subjects completed 2 min of CPR on their respective CPR training modalities, followed by an additional 2 min post-simulation CPR evaluation with no feedback. We hypothesized that the AR CPR training application would confer improved CPR quality defined as chest compression rate and depth compared with the standard AV feedback training.

Results: Between January 2019 and May 2019, 100 HCPs were enrolled (50 in the CPReality cohort and 50 in the standard AV manikin cohort). The mean chest compression (CC) rate for all subjects during the intervention was 118 ± 15 cpm, and CC depth was 50 ± 8; post-intervention the CC rate was 120 ± 13 and CC depth was 51 ± 8. The mean CC rate for those trained with CPReality was 121 ± 3 compared with the standard CPR manikin training which was 114 ± 1 cpm (p < 0.006); CC depth was 48 ± 1 mm vs. 52 ± 1 (p = 0.007), respectively. Post-simulation CPR quality with no feedback showed a mean CC rate for the CPReality application at 122 ± 15 cpm compared with the standard CPR manikin at 117 ± 11 cpm (p = 0.09); depth was 49 ± 8 mm vs. 52 ± 8 (p = 0.095), respectively. In the post-survey, 79% of CPReality subjects agreed that the AR application provided a realistic patient presence compared with 59% (p = 0.07) of subjects in the standard CPR manikin cohort.

Conclusions: In a randomized trial of an AR CPR training application compared with a standard CPR manikin training, the AR CPR application did not improve the quality of CPR performed during a CPR refresher training compared with the standard training in HCPs. Future studies should investigate the use of this and other digital technologies for CPR training and education.

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 standard and over-the-head method of chest compressions during cardiopulmonary resuscitation - a simulation study

Background

Maintaining highly effective cardiopulmonary resuscitation (CPR) can be particularly difficult when artificial ventilation using a bag-valve-mask device, combined with chest compression have to be carried out by one person. The aim of the study is to compare the quality of CPR conducted by one paramedic using chest compression from the patient’s side with compression conducted from the ‘over-the-head’ position.

Methods

The subject of the study were two methods of CPR – ‘standard’ (STD) and ‘over-the-head’ (OTH). The STD method consisted of cycles of 30 chest compressions from the patient’s side, and two attempts at artificial ventilation after moving round to behind the patient’s head. In the OTH method, both compressions and ventilations were conducted from behind the patient’s head.

Results

Both CPR methods were conducted by 38 paramedics working in medical response teams. Statistical analysis was conducted on the data collected, giving the following results: the average time of the interruptions between compression cycles (STD 9.184 s, OTH 7.316 s, p < 0.001); the depth of compression 50–60 mm (STD 50.65%, OTH 60.22%, p < 0.001); the rate of compression 100–120/min. (STD 46.39%, OTH 53.78%, p < 0.001); complete chest wall recoil (STD 84.54%, OTH 91.46%, p < 0.001); correct hand position (STD 99.32%, OTH method 99.66%, p < 0.001). A statistically significant difference was demonstrated in the results to the benefit of the OTH method in the above parameters. The remaining parameters showed no significant differences in comparison to reference values.

Conclusions

The higher quality of CPR in the simulated research using the OTH method by a single person justifies the use of this method in a wider range of emergency interventions.

Mechanical chest compression with LUCAS device does not improve clinical outcome in out-of-hospital cardiac arrest patients: A systematic review and meta-analysis

BACKGROUND

Cardiac arrest (CA) is a serious threat to human health. Cardiopulmonary resuscitation (CPR) is an effective treatment for CA. Early and high-quality CPR is closely related to the survival rate of patients with CA. But manual chest compression has a lot of defects. To solve the defects and improve the quality of CPR, mechanical CPR device was invented. However, it has still controversy whether manual chest compression or mechanical chest compression is better. This systematic review was aimed to investigate the difference in clinical outcomes between manual chest compression and Lund University Cardiac Assist System (LUCAS) assisted CPR in patients with out-hospital CA.

METHODS

Original research studies, conducted on adult out-of-hospital CA, were included. PubMed/Medline, EMBASE, Scopus, Cochrane Library, CNKI, and Wanfang database were searched from the setting to February 21, 2019. Odds ratio (OR) with 95% confidence interval (CI) was selected as effect scale index for evaluation of the difference in return of spontaneous circulation (ROSC), survival to hospital admission, survival to hospital discharge, and survival to 30 days. Random effects model was used in this study to estimate overall mean effects.

RESULTS

A total of 6 articles, including 4 randomized controlled trials and 2 nonrandomized controlled trials, were selected. And 8501 subjects were involved to analyze the clinical outcomes of LUCAS and manual chest compression for patients with out-hospital CA. Comparisons of ROSC (33.3% vs 33.0%, P = .98; OR = 1; 95% CI: [0.89,1.13]), survival to hospital admission (22.7% vs 24.3%, P = .32; OR = 0.86; 95% CI: [0.65,1.15]), survival to hospital discharge (8.6% vs 10.7%, P = .50; OR = 0.92; 95% CI: [0.73,1.17]), and survival to 30 days (7.5% vs 8.5%, P = .50; OR = 0.92; 95% CI: [0.73,1.17]) were made. No significant difference was found.

CONCLUSION

The synthesis of available evidence does not support that mechanical chest compression with LUCAS device improves clinical outcome in out-of-hospital CA patients compared with manual chest compression. Large scale studies with improved designs are still needed in the future.

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.

Two-site regional oxygen saturation and capnography monitoring during resuscitation after cardiac arrest in a swine pediatric ventricular fibrillatory arrest model

To investigate the use of two-site regional oxygen saturations (rSO₂) and end tidal carbon dioxide (EtCO₂) to assess the effectiveness of resuscitation and return of spontaneous circulation (ROSC). Eight mechanically ventilated juvenile swine underwent 28 ventricular fibrillatory arrests with open cardiac massage. Cardiac massage was administered to achieve target pulmonary blood flow (PBF) as a percentage of pre-cardiac arrest baseline. Non-invasive data, including, EtCO₂, cerebral rSO₂ (C-rSO₂) and renal rSO₂ (R-rSO₂) were collected continuously. Our data demonstrate the ability to measure both rSO₂ and EtCO₂ during CPR and after ROSC. During resuscitation EtCO₂ had a strong correlation with goal CO with r = 0.83 (p < 0.001) 95% CI [0.67–0.92]. Both C-rSO₂ and R-rSO₂ had moderate and statistically significant correlation with CO with r = 0.52 (p = 0.003) 95% CI (0.19–0.74) and 0.50 (p = 0.004) 95% CI [0.16–0.73]. The AUCs for sudden increase of EtCO₂, C-rSO₂, and R-rSO₂ at ROSC were 0.86 [95% CI, 0.77–0.94], 0.87 [95% CI, 0.8–0.94], and 0.98 [95% CI, 0.96–1.00] respectively. Measurement of continuous EtCO₂ and rSO₂ may be used during CPR to ensure effective chest compressions. Moreover, both rSO₂ and EtCO₂ may be used to detect ROSC in a swine pediatric ventricular fibrillatory arrest model.

Association between left ventricular outflow tract opening and successful resuscitation after cardiac arrest

BACKGROUND

Survival after cardiac arrest depends on adequate cardiopulmonary resuscitation (CPR). Manual or mechanical external chest compression may be ineffective to restore circulation: structures subjected to external chest compression may differ in forces transfer to intrathoracic structures due to anatomic characteristics and physiological changes. This clinical study aims to assess the association of trans-oesophageal findings during CPR and successful resuscitation.

METHODS

Retrospective cohort study. Trans-oesophageal assessment of right ventricular fractional area change, right ventricular outflow tract fractional shortening, left ventricular volumes, ejection fraction, and aortic diameters were performed in refractory out-of-hospital cardiac arrest patients admitted to emergency department for extracorporeal CPR.

RESULTS

19 patients were analyzed. 15 of 19 patients (79%) received venous-arterial extracorporeal membrane oxygenation support. Resuscitation was successful with return of spontaneous circulation or electromechanical activity in 7 patients (group-SUXX) and failed in 12 patients (group-FAIL). 6 patients (32%) were alive at 24 h from the cardiac arrest, one patient (5%) survived to hospital discharge. Left ventricular outflow tract (LVOT) was open during CPR in all patients in group-SUXX and in 1 patient in group-FAIL (p 0.0002). None of the patients with closed LVOT had successful resuscitation. Patients in group-SUXX had a higher ejection fraction (p 0.03), ascending aortic diameter (p 0.04), and survival rate than those in group-FAIL (p 0.015). In a multiple variable Cox's proportional model LVOT opening was the only variable associated with successful resuscitation.

CONCLUSIONS

Trans-oesophageal echocardiography can be useful in the emergency setting of cardiopulmonary arrest for discriminating between successful and failing resuscitation.

Identification of return of spontaneous circulation during cardiopulmonary resuscitation via pulse oximetry in a porcine animal cardiac arrest model

In this prospective study we investigated whether the pulse oximetry plethysmographic waveform (POP) could be used to identify return of spontaneous circulation (ROSC) during cardio-pulmonary resuscitation (CPR). Tweleve pigs (28 ± 2 kg) were randomly assigned to two groups: Group I (non-arrested with compressions) (n = 6); Group II (arrested with CPR and defibrillation) (n = 6). Hemodynamic parameters and POP were collected and analyzed. POP was analyzed using both a time domain method and a frequency domain method. In Group I, when compressions were carried out on subjects with a spontaneous circulation, a hybrid fluctuation or "envelope" phenomenon appeared in the time domain method and a "double" or "fusion" peak appeared in the frequency domain method. In Group II, after the period of ventricular fibrillation was induced, the POP waveform disappeared. With compressions, POP showed a regular compression wave. After defibrillation, ROSC, and continued compressions, a hybrid fluctuation or "envelope" phenomenon appeared in the time domain method and a "double" or "fusion" peak appeared in the frequency domain method, similar to Group I. Analysis of POP using the time and frequency domain methods could be used to identify ROSC during CPR.

A prospective evaluation of the 'C.O.A.C.H.E.D.' cognitive aid for emergency defibrillation

INTRODUCTION

International guidelines recommend that interruptions to chest compressions are minimised during defibrillation. As a result, some resuscitation educators have adopted a more structured approach to defibrillation. One such approach is the 'C.O.A.C.H.E.D.' cognitive aid (Continue compressions, Oxygen away, All others away, Charging, Hands off, Evaluate, Defibrillate or Disarm). To date, there are no studies assessing the use of this cognitive aid.

METHODS

This study utilised an Emergency Department in situ simulated model of cardiac arrest. The defibrillator used was a proprietary R-Series (Zoll, PA, USA) connected to a CS1201 rhythm generator (Symbio, Beaverton, OR, USA). The study cohorts were interdisciplinary advanced life support (ALS) providers. Paired providers were enrolled in a mechanical CPR (M-CPR) training programme with no feedback related to defibrillation performance. As part of this 6-month programme, serial defibrillation performance was assessed. The outcome measures were the length of 'peri-shock' pause and 'safety' of defibrillation practice. Comparative statistical analysis using the Mann-Whitney U-test was made between groups of providers with 'correct use or near correct' or 'entirely incorrect or absent' use of the cognitive aid.

RESULTS

The C.O.A.C.H.E.D. cognitive aid was applied correctly in 92 of 109 defibrillations. Providers with correct cognitive aid use had a median length of peri-shock pause time of 6.0s (IQR 5.0-7.0). Providers with 'entirely incorrect or absent' cognitive aid use had a peri-shock pause time of 8.0s (IQRF 6.6-10.0) (p≤0.001). No unsafe defibrillation practices were observed.

CONCLUSION

In this observational study of defibrillation performance, the use of the C.O.A.C.H.E.D. cognitive aid was associated with a significant decrease in the length of peri-shock pause. Therefore, we conclude that the use of a cognitive aid is appropriate for teaching and performing defibrillation.

Bedside Identification of Massive Pulmonary Embolism with Point-of-Care Transesophageal Echocardiography

BACKGROUND

Pulmonary embolism can be difficult to diagnose, particularly in those who are hemodynamically unstable and cannot be imaged to confirm the diagnosis. Echocardiography can allow for rapid assessment of patients in shock, but requires adequate transthoracic windows to obtain clinically useful information. Emergency physician-performed transesophageal echocardiography (TEE) may be a useful tool when transthoracic echocardiography fails.

CASE REPORT

An 86-year-old woman presented to the emergency department after a fall at home. She rapidly decompensated in the emergency department and sustained a pulseless electrical activity cardiac arrest. Attempts made during the resuscitation to obtain transthoracic echocardiographic views to elicit the cause of the patient's cardiac arrest were unsuccessful. An emergency physician, with previous focused training in TEE, performed emergent TEE. The TEE examination rapidly revealed a dilated right ventricle and an empty, hyperdynamic left ventricle, suggestive of an unsuspected massive acute pulmonary embolism. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: With continued growth and utility of point-of-care ultrasound in emergency medicine, TEE provides an attractive means to assess critically ill patients that may not otherwise be assessable.

Comparison of continuous compression with regular ventilations versus 30:2 compressions-ventilations strategy during mechanical cardiopulmonary resuscitation in a porcine model of cardiac arrest

Background

A compression-ventilation (C:V) ratio of 30:2 is recommended for adult cardiopulmonary resuscitation (CPR) by the current American Heart Association (AHA) guidelines. However, continuous chest compression (CCC) is an alternative strategy for CPR that minimizes interruption especially when an advanced airway exists. In this study, we investigated the effects of 30:2 mechanical CPR when compared with CCC in combination with regular ventilation in a porcine model.

Methods

Sixteen male domestic pigs weighing 39±2 kg were utilized. Ventricular fibrillation was induced and untreated for 7 min. The animals were then randomly assigned to receive CCC combined with regular ventilation (CCC group) or 30:2 CPR (VC group). Mechanical chest compression was implemented with a miniaturized mechanical chest compressor. At the same time of beginning of precordial compression, the animals were mechanically ventilated at a rate of 10 breaths-per-minute in the CCC group or with a 30:2 C:V ratio in the VC group. Defibrillation was delivered by a single 150 J shock after 5 min of CPR. If failed to resuscitation, CPR was resumed for 2 min before the next shock. The protocol was stopped if successful resuscitation or at a total of 15 min. The resuscitated animals were observed for 72 h.

Results

Coronary perfusion pressure, end-tidal carbon dioxide and carotid blood flow in the VC group were similar to those achieved in the CCC group during CPR. No significant differences were observed in arterial blood gas parameters between two groups at baseline, VF 6 min, CPR 4 min and 30, 120 and 360 min post-resuscitation. Although extravascular lung water index of both groups significantly increased after resuscitation, no distinct difference was found between CCC and VC groups. All animals were successfully resuscitated and survived for 72 h with favorable neurologic outcomes in both groups. However, obviously more numbers of rib fracture were observed in CCC animals in comparison with VC animals.

Conclusions

There was no difference in hemodynamic efficacy and gas exchange during and after resuscitation, therefore identical 72 h survival with intact neurologic function was observed in both VC and CCC groups. However, the incidence of rib fracture increases during the mechanical CPR strategy of CCC combined with regular ventilations.

Exchange of supraglottic airways for endotracheal tube using the Eschmann Introducer during simulated child resuscitation: A randomized study comparing 4 devices

BACKGROUND

The aim of this study was to examine the application of the Eschmann tracheal tube introducer (ETTI) with 4 types of supraglottic airway devices (SADs) using a child-manikin.

METHODS

A total of 79 paramedics were asked to exchange the 4 SADs for an endotracheal tube with the ETTI in 3 different scenarios using a randomized crossover study format: normal airway without chest compression; normal airway with uninterrupted chest compression; and difficult airway with uninterrupted chest compression. The primary outcome was time to SAD exchange, with the secondary outcome measuring the success of SAD exchange. Each attempt was assessed by a trained assistant.

RESULTS

The mean exchange times for LMA, Cobra PLA, Air-Q, and SALT were as follows: 21, 23, 21, and 18, respectively for Scenario A; 23, 27, 22.5, and 21 for Scenario B; and 23, 28, 23, and 23 for Scenario C. The percent efficacy of SADs exchange with LMA, Cobra PLA, Air-Q and SALT were 98.7%, 94.9%, 100%, and 100% for scenario A; 98.7%, 88.6%, 98.7%, and 97.5% for scenario B; and 93.7%, 87.3%, 94.9%, and 93.7% for scenario C.

CONCLUSIONS

In this model of pediatric resuscitation, the SAD exchange using an ETTI has (LMA, Cobra PLA, Air-Q and SALT) proved to be effective in paramedics with no previous experience. Furthermore, experimental findings indicated that SAD exchange can be achieved without interrupting chest compression.

Bystander fatigue and CPR quality by older bystanders: a randomized crossover trial comparing continuous chest compressions and 30:2 compressions to ventilations

Objectives

This study sought to measure bystander fatigue and cardiopulmonary resuscitation (CPR) quality after five minutes of CPR using the continuous chest compression (CCC) versus the 30:2 chest compression to ventilation method in older lay persons, a population most likely to perform CPR on cardiac arrest victims.

Methods

This randomized crossover trial took place at three tertiary care hospitals and a seniors’ center. Participants were aged ≥55 years without significant physical limitations (frailty score ≤3/7). They completed two 5-minute CPR sessions (using 30:2 and CCC) on manikins; sessions were separated by a rest period. We used concealed block randomization to determine CPR method order. Metronome feedback maintained a compression rate of 100/minute. We measured heart rate (HR), mean arterial pressure (MAP), and Borg Exertion Scale. CPR quality measures included total number of compressions and number of adequate compressions (depth ≥5 cm).

Results

Sixty-three participants were enrolled: mean age 70.8 years, female 66.7%, past CPR training 60.3%. Bystander fatigue was similar between CPR methods: mean difference in HR -0.59 (95% CI −3.51-2.33), MAP 1.64 (95% CI −0.23-3.50), and Borg 0.46 (95% CI 0.07-0.84). Compared to 30:2, participants using CCC performed more chest compressions (480.0 v. 376.3, mean difference 107.7; p<0.0001) and more adequate chest compressions (381.5 v. 324.9, mean difference. 62.0; p=0.0001), although good compressions/minute declined significantly faster with the CCC method (p=0.0002).

Conclusions

CPR quality decreased significantly faster when performing CCC compared to 30:2. However, performing CCC produced more adequate compressions overall with a similar level of fatigue compared to the 30:2 method.

Hands-on defibrillation during active chest compressions: eliminating another interruption

After decades of research, effective chest compressions have emerged as a key component of high-quality cardiopulmonary resuscitation (CPR) for cardiac arrest patients. Minimizing interruptions in chest compressions is garnering increasing attention as a method to improve CPR quality and outcomes. Hands-on defibrillation has been suggested as both a safe and effective means of reducing interruptions in chest compressions. This article discusses the safety and efficacy of a novel and controversial method to reduce interruptions: hands-on defibrillation.

Impact of a feedback device on chest compression quality during extended manikin CPR: a randomized crossover study

PURPOSES

Chest compressions require physical effort leading to increased fatigue and rapid degradation in the quality of cardiopulmonary resuscitation overtime. Despite harmful effect of interrupting chest compressions, current guidelines recommend that rescuers switch every 2 minutes. The impact on the quality of chest compressions during extended cardiopulmonary resuscitation has yet to be assessed.

BASIC PROCEDURES

We conducted randomized crossover study on manikin (ResusciAnne; Laerdal). After randomization, 60 professional emergency rescuers performed 2 × 10 minutes of continuous chest compressions with and without a feedback device (CPRmeter). Efficient compression rate (primary outcome) was defined as the frequency target reached along with depth and leaning at the same time (recorded continuously).

MAIN FINDINGS

The 10-minute mean efficient compression rate was significantly better in the feedback group: 42% vs 21% (P< .001). There was no significant difference between the first (43%) and the tenth minute (36%; P= .068) with feedback. Conversely, a significant difference was evident from the second minute without feedback (35% initially vs 27%; P< .001). The efficient compression rate difference with and without feedback was significant every minute, from the second minute onwards. CPRmeter feedback significantly improved chest compression depth from the first minute, leaning from the second minute and rate from the third minute.

PRINCIPAL CONCLUSIONS

A real-time feedback device delivers longer effective, steadier chest compressions over time. An extrapolation of these results from simulation may allow rescuer switches to be carried out beyond the currently recommended 2 minutes when a feedback device is used.

Influence of Chest Compressions on Circulation during the Peri-Cardiac Arrest Period in Porcine Models

Objective

Starting chest compressions immediately after a defibrillation shock might be harmful, if the victim already had a return of spontaneous circulation (ROSC) and yet was still being subjected to external compressions at the same time. The objective of this study was to study the influence of chest compressions on circulation during the peri-cardiac arrest period.

Design

Prospective, randomized controlled study.

Setting

Animal experimental center in Peking Union Medical Collage Hospital, Beijing, China.

Subjects

Healthy 3-month-old male domestic pigs.

Interventions

44 pigs (28±2 kg) were randomly assigned to three groups: Group I (non-arrested with compressions) (n = 12); Group II (arrested with compressions only) (n = 12); Group III (ROSC after compressions and defibrillation) (n = 20). In Groups I and II, compressions were performed to a depth of 5cm (Ia and IIa, n = 6) or a depth of 3cm (Ib and IIb, n = 6) respectively, while in Group III, the animals which had just achieved ROSC (n = 18) were compressed to a depth of 5cm (IIIa, n = 6), a depth of 3cm (IIIb, n = 6), or had no compressions (IIIc, n = 6). Hemodynamic parameters were collected and analyzed.

Measurements and Findings

Hemodynamics were statistically different between Groups Ia and Ib when different depths of compressions were performed (p < 0.05). In Group II, compressions were beneficial and hemodynamics correlated with the depth of compressions (p < 0.05). In Group III, compressions that continued after ROSC produced a reduction in arterial pressure (p < 0.05).

Conclusions

Chest compressions might be detrimental to hemodynamics in the early post-ROSC stage. The deeper the compressions were, the better the effect on hemodynamics during cardiac arrest, but the worse the effect on hemodynamics after ROSC.

Hands-on defibrillation and electrocardiogram artefact filtering technology increases chest compression fraction and decreases peri-shock pause duration in a simulation model of cardiac arrest

Background

Reducing pauses during cardiopulmonary resuscitation (CPR) compressions result in better outcomes in cardiac arrest. Artefact filtering technology (AFT) gives rescuers the opportunity to visualize the underlying electrocardiogram (ECG) rhythm during chest compressions, and reduces the pauses that occur before and after delivering a shock. We conducted a simulation study to measure the reduction of peri-shock pause and impact on chest compression fraction (CCF) through AFT.

Methods

In a simulator setting, participants were given a standardized cardiac arrest scenario and were randomly assigned to perform CPR/defibrillation using the protocol from one of three experimental arms: 1) Standard of Care (pauses for rhythm analysis and shock delivery); 2) AFT (no pauses for rhythm analysis, but a pause for defibrillation); or 3) AFT with hands-on defibrillation (no pauses for rhythm analysis or defibrillation). The primary outcomes were CCF and peri-shock pause duration, with secondary outcomes of pre- and post-shock pause duration.

Results

AFT with hands-on defibrillation was found to have the highest CCF (86.4%), as compared to AFT alone (83.8%, p<0.001), and both groups significantly improved CCF in comparison with the Standard of Care (76.7%, p<0.001). AFT with hands-on defibrillation was associated with a reduced peri-shock pause (2.6 seconds) as compared to AFT alone (5.3 seconds, p<0.001), and the Standard of Care (7.4 seconds, p<0.001).

Conclusions

In this cardiac arrest model, AFT results in a greater CCF by reducing peri-shock pause duration. There is also a small but detectable improvement in CCF with the addition of hands-on defibrillation.

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.

Cardiac arrest: the changing incidence of ventricular fibrillation

OPINION STATEMENT

There are more than 300,000 out-of-hospital cardiac arrests (OHCA) in the USA annually, which can be grouped into those presenting with tachyarrhythmic (shockable) rhythms and those presenting with non-tachyarrhythmic rhythms. The incidence of tachyarrhythmic rhythms, which include ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT), has been noted to be progressively decreasing in multiple studies of OHCA. Improved medical and surgical therapies for ischemic heart disease, and the widespread use of implantable cardiac defibrillators (ICDs), have likely contributed to a declining incidence of VF arrest and may result in conversion of an otherwise VF event into a pulseless electrical activity (PEA) arrest. As the incidence of VF has declined, it is unclear if the absolute incidence of non-tachyarrhythmic rhythms has increased or remained largely unchanged. This article discusses the changing rates of presenting rhythms in sudden cardiac arrest, the underlying cellular mechanisms of PEA, the factors contributing to the relative increase in the rate of PEA arrests, and current treatment options.