Does Point-of-care Ultrasound Use Impact Resuscitation Length, Rates of Intervention, and Clinical Outcomes During Cardiac Arrest? A Study from the Sonography in Hypotension and Cardiac Arrest in the Emergency Department (SHoC-ED) Investigators

Can absence of cardiac activity on point-of-care echocardiography predict death in out-of-hospital cardiac arrest? A systematic review and meta-analysis

AIM

The purpose of this systematic review and meta-analysis was to evaluate the accuracy of the absence of cardiac motion on point-of-care echocardiography (PCE) in predicting termination of resuscitation (TOR), short-term death (STD), and long-term death (LTD), in adult patients with cardiac arrest of all etiologies in out-of-hospital and emergency department setting.

METHODS

A systematic review and meta-analysis was conducted based on PRISMA guidelines. A literature search in Medline, EMBASE, Cochrane, WHO registry, and ClinicalTrials.gov was performed from inspection to August 2022. Risk of bias was evaluated using QUADAS-2 tool. Meta-analysis was divided into medical cardiac arrest (MCA) and traumatic cardiac arrest (TCA). Sensitivity and specificity were calculated using bivariate random-effects, and heterogeneity was analyzed using I2 statistic.

RESULTS

A total of 27 studies (3657 patients) were included in systematic review. There was a substantial variation in methodologies across the studies, with notable difference in inclusion criteria, PCE timing, and cardiac activity definition. In MCA (15 studies, 2239 patients), the absence of cardiac activity on PCE had a sensitivity of 72% [95% CI 62-80%] and specificity of 80% [95% CI 58-92%] to predict LTD. Although the low numbers of studies in TCA preluded meta-analysis, all patients who lacked cardiac activity on PCE eventually died.

CONCLUSIONS

The absence of cardiac motion on PCE for MCA predicts higher likelihood of death but does not have sufficient accuracy to be used as a stand-alone tool to terminate resuscitation. In TCA, the absence of cardiac activity is associated with 100% mortality rate, but low number of patients requires further studies to validate this finding. Future work would benefit from a standardized protocol for PCE timing and agreement on cardiac activity definition.

The role of point-of-care ultrasound (POCUS) imaging in clinical outcomes during cardiac arrest: a systematic review

BACKGROUND

Cardiac arrest in hospital and out-of-hospital settings is associated with high mortality rates. Therefore, a bedside test that can predict resuscitation outcomes of cardiac arrest patients is of great value. Point-of-care ultrasound (POCUS) has the potential to be used as an effective diagnostic and prognostic tool during cardiac arrest, particularly in observing the presence or absence of cardiac activity. However, it is highly susceptible to "self-fulfilling prophecy" and is associated with prolonged cardiopulmonary resuscitation (CPR), which negatively impacts the survival rates of cardiac arrest patients. As a result, the current systematic review was created to assess the role of POCUS in predicting the clinical outcomes associated with out-of-hospital and in-hospital cardiac arrests.

METHODS

The search for scientific articles related to our study was done either through an electronic database search (i.e., PubMed, Medline, ScienceDirect, Embase, and Google Scholar) or manually going through the reference list of the relevant articles. A quality appraisal was also carried out with the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2), and the prognostic test performance (sensitivity and sensitivity) was tabulated.

RESULTS

The search criteria yielded 3984 articles related to our topic, of which only 22 were eligible for inclusion. After reviewing the literature, we noticed a wide variation in the definition of cardiac activity, and the statistical heterogeneity was high; therefore, we could not carry out meta-analyses. The tabulated clinical outcomes based on initial cardiac rhythm and definitions of cardiac activity showed highly inconsistent results.

CONCLUSION

POCUS has the potential to provide valuable information on the management of cardiac arrest patients; however, it should not be used as the sole predictor for the termination of resuscitation efforts.

POCUS literature primer: key papers on POCUS in cardiac arrest and shock

OBJECTIVE

The objective of this study is to identify the top five most influential papers published on the use of point-of-care ultrasound (POCUS) in cardiac arrest and the top five most influential papers on the use of POCUS in shock in adult patients.

METHODS

An expert panel of 14 members was recruited from the Canadian Association of Emergency Physicians (CAEP) Emergency Ultrasound Committee and the Canadian Ultrasound Fellowship Collaborative. The members of the panel are ultrasound fellowship trained or equivalent, are engaged in POCUS research, and are leaders in POCUS locally and nationally in Canada. A modified Delphi process was used, consisting of three rounds of sequential surveys and discussion to achieve consensus on the top five most influential papers for the use of POCUS in cardiac arrest and shock.

RESULTS

The panel identified 39 relevant papers on POCUS in cardiac arrest and 42 relevant papers on POCUS in shock. All panel members participated in all three rounds of the modified Delphi process, and we ultimately identified the top five most influential papers on POCUS in cardiac arrest and also on POCUS in shock. Studies include descriptions and analysis of safe POCUS protocols that add value from a diagnostic and prognostic perspective in both populations during resuscitation.

CONCLUSION

We have developed a reading list of the top five influential papers on the use of POCUS in cardiac arrest and shock to better inform residents, fellows, clinicians, and researchers on integrating and studying POCUS in a more evidence-based manner.

Focused Ultrasonography in Cardiac Arrest

Rapid diagnostic tools available to the emergency physician caring for cardiac arrest patients are limited. Focused ultrasound (US), and in particular, focused echocardiography, is a useful tool in the evaluation of patients in cardiac arrest. It can help identify possible causes of cardiac arrest like tamponade and pulmonary embolism, which can guide therapy. US can also yield prognostic information, with lack of cardiac activity being highly specific for failure to achieve return of spontaneous circulation. US may also be used to aid in procedural guidance. Recently, focused transesophageal echocardiography has been used in the emergency department setting.

Impact of Ultrasonography on Chest Compression Fraction and Survival in Patients with Out-of-hospital Cardiac Arrest

INTRODUCTION

Whether ultrasonography (US) contributes to delays in chest compressions and hence a negative impact on survival is uncertain. In this study we aimed to investigate the impact of US on chest compression fraction (CCF) and patient survival.

METHODS

We retrospectively analyzed video recordings of the resuscitation process in a convenience sample of adult patients with non-traumatic, out-of-hospital cardiac arrest. Patients receiving US once or more during resuscitation were categorized as the US group, while the patients who did not receive US were categorized as the non-US group. The primary outcome was CCF, and the secondary outcomes were the rates of return of spontaneous circulation (ROSC), survival to admission and discharge, and survival to discharge with a favorable neurological outcome between the two groups. We also evaluated the individual pause duration and the percentage of prolonged pauses associated with US.

RESULTS

A total of 236 patients with 3,386 pauses were included. Of these patients, 190 received US and 284 pauses were related to US. Longer resuscitation duration was observed in the US group (median, 30.3 vs 9.7 minutes, P<.001). The US group had comparable CCF (93.0% vs 94.3%, P=0.29) with the non-US group. Although the non-US group had a better rate of ROSC (36% vs 52%, P=0.04), the rates of survival to admission (36% vs 48%, P=0.13), survival to discharge (11% vs 15%, P=0.37), and survival with favorable neurological outcome (5% vs 9%, P=0.23) did not differ between the two groups. The pause duration of pulse checks with US was longer than pulse checks alone (median, 8 vs 6 seconds, P=0.02). The percentage of prolonged pauses was similar between the two groups (16% vs 14%, P=0.49).

CONCLUSION

When compared to the non-ultrasound group, patients receiving US had comparable chest compression fractions and rates of survival to admission and discharge, and survival to discharge with a favorable neurological outcome. The individual pause was lengthened related to US. However, patients without US had a shorter resuscitation duration and a better rate of ROSC. The trend toward poorer results in the US group was possibly due to confounding variables and nonprobability sampling. It should be better investigated in further randomized studies.

Role of initial cardiac activity assessed by point-of-care ultrasonography in predicting cardiac arrest outcomes: A prospective cohort study

OBJECTIVES

This study was conducted to investigate the association between visible cardiac activity in point-of-care ultrasound (POCUS) and outcomes of cardiac arrest such as the return of spontaneous circulation (ROSC), survival to inpatient admission (SIA), and survival to hospital discharge (STHD).

METHODS

This was a single-center, prospective cohort study conducted in the emergency department (ED). Adult (age >18 years) patients in cardiac arrest were included in the study. Exclusion criteria of the study were - traumatic arrest, out-of-hospital cardiac arrest resuscitated before ED admission, and patients presenting with initial shockable rhythm. Patients whose ultrasound images could not be obtained and whose resuscitation stopped following POCUS were also excluded from the study. POCUS examination was done after 2 min of initiation of cardiopulmonary resuscitation (CPR) and visible cardiac activity was defined as any visible movement of the myocardium, excluding movement of blood within cardiac chambers, or isolated valve movement. The duration of POCUS examinations was limited to 10 s. The association of initial cardiac activity in POCUS with the outcomes of cardiac arrest was investigated.

RESULTS

Out of 140 patients screened, 84 patients were included in the study. Rates of ROSC, SIA, and STHD were found in 23 (27.4%), 9 (10.7%), and 2 (2.4%) patients, respectively. Only 15 out of 84 (17.9%) patients had cardiac activity on the initial POCUS examination. Cardiac activity was seen in 52.2% of patients with ROSC, which was significantly higher (P < 0.001) as compared with the no-ROSC group (4.9%). Unlike the above association, there was no difference in the incidence of initial cardiac activity in patient groups who got admitted (SIA) and discharged (STHD) versus those who died. In the multivariate regression analysis, the duration of CPR and initial cardiac activity significantly predicted the rate of ROSC, with an adjusted odds ratio of 0.93 (95% confidence interval [CI]: 0.86-0.99, P = 0.04) and 24.8 (95% CI: 3.17-89.41, P = 0.002), respectively. None of the variables predicted SIA and STHD. The positive likelihood ratio of cardiac activity for predicting ROSC, SIA, and STHD were 10.6, 2.1, and 2.9, respectively.

CONCLUSION

Integration of POCUS in cardiac arrest resuscitation was shown to be helpful in terms of prognostic significance of the presence of initial cardiac activity in terms of ROSC.

Point-of-care ultrasound for critically-ill patients: A mini-review of key diagnostic features and protocols

Point-of-care ultrasonography (POCUS) for managing critically ill patients is increasingly performed by intensivists or emergency physicians. Results of needs surveys among intensivists reveal emphasis on basic cardiac, lung and abdominal ultrasound, which are the commonest POCUS modalities in the intensive care unit. We therefore aim to describe the key diagnostic features of basic cardiac, lung and abdominal ultrasound as practised by intensivists or emergency physicians in terms of accuracy (sensitivity, specificity), clinical utility and limitations. We also aim to explore POCUS protocols that integrate basic cardiac, lung and abdominal ultrasound, and highlight areas for future research.

A Systemic Review on the Diagnostic Accuracy of Point-of-Care Ultrasound in Patients With Undifferentiated Shock in the Emergency Department

Early identification of the shock type and correct diagnosis is associated with better outcomes. Previous studies have suggested that point-of-care ultrasound (POCUS) increases the diagnostic accuracy of patients in undifferentiated shock. However, a complete overview of the diagnostic accuracy of POCUS and the related treatment changes when compared to standard care is still limited. Our objective was to compare POCUS against standard practice regarding the diagnostic accuracy and specific therapeutic management changes (fluid volume administration and vasopressor use) in patients with undifferentiated shock in the emergency department (ED). We conducted a systematic review in concordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. A systematic search was performed using Embase, PubMed, Cochrane Central Register for Controlled Trials, and clinicaltrials.gov. Two physicians independently selected the articles and assessed the quality of the studies independently with the Quadas-2 tool. All included studies used POCUS in adult patients in undifferentiated shock and described diagnostic accuracy or specific therapeutic management changes (fluid volume administration or vasopressor use) and compared this to standard care. The primary outcome was diagnostic accuracy. Secondary outcomes were the amount of fluid administered and vasopressor use in the ED. Only articles published after 1996 were included. There were 10,805 articles found of which 6 articles were included. Four out of six studies reported diagnostic accuracy, three reported on fluid administration and vasopressors. We found that the diagnostic accuracy improved through the use of POCUS when compared to the standard care group, increasing overall diagnostic accuracy from 45-60% to 80-89% when combined with clinical information. There was no significant difference in fluid administration or vasopressor use between the groups. In our systematic review, we found that the use of POCUS in patients that presented with undifferentiated shock in the ED improved the diagnostic accuracy of the shock type and final diagnosis. POCUS resulted in no changes in fluid administration or vasopressor use when compared to standard care. However, the results should be interpreted within the limitations of some of the studies that were included in the review.

Point-of-care ultrasound in cardiorespiratory arrest (POCUS-CA): narrative review article

The POCUS-CA (Point-of-care ultrasound in cardiac arrest) is a diagnostic tool in the Intensive Care Unit and Emergency Department setting. The literature indicates that in the patient in a cardiorespiratory arrest it can provide information of the etiology of the arrest in patients with non-defibrillable rhythms, assess the quality of compressions during cardiopulmonary resuscitation (CPR), and define prognosis of survival according to specific findings and, thus, assist the clinician in decision-making during resuscitation. This narrative review of the literature aims to expose the usefulness of ultrasound in the setting of cardiorespiratory arrest as a tool that allows making a rapid diagnosis and making decisions about reversible causes of this entity. More studies are needed to support the evidence to make ultrasound part of the resuscitation algorithms. Teamwork during cardiopulmonary resuscitation and the inclusion of ultrasound in a multidisciplinary approach is important to achieve a favorable clinical outcome.

The use of critical care echocardiography in peri-arrest and cardiac arrest scenarios: Pros, cons and what the future holds

Echocardiography is being increasingly deployed as a diagnostic and monitoring tool in the critically ill. This rise in popularity has led to its recommendation as a core competence in intensive care, with several training routes available. In the peri-arrest and cardiac arrest population, point of care focused echocardiography has the potential to transform patient care and improve outcomes. Be it via diagnosis of shock aetiology and reversibility or assessing response to treatment and prognostication. This narrative review discusses current and future applications of echocardiography in this patient group and provides a structure with which one can approach such patients.

The Role of Cardiac Arrest Sonographic Exam (CASE) in Predicting the Outcome of Cardiopulmonary Resuscitation; a Cross-sectional Study

INTRODUCTION

Ultrasonography (US) has been suggested as an integral part of resuscitation to identify potentially reversible causes of cardiac arrest (CA). This study aimed to evaluate the association between cardiac activity on ultrasonography during resuscitation and outcome of patients with non-shockable rhythms.

METHODS

We conducted a prospective, observational study on adult patients presenting with CA or experiencing CA in the emergency department (ED), and initial non-shockable rhythm. US examination of the sub-xiphoid region was performed during the 10-second interval of rhythm and pulse check and the association of US findings and patients' outcomes was evaluated.

RESULTS

151 patients with the mean age of 65.32 ± 11.68 years were evaluated (76.2% male). 43 patients (28.5%) demonstrated cardiac activity on the initial US. The rate of asystole in initial rhythm was 58.9% (n=89). Return of spontaneous circulation (ROSC) was achieved in 36 (23.8%) patients, twenty (13.2%) survived to hospital admission and seven (4.6%) survived to hospital discharge. When the cardiac standstill duration increased to six minutes, no patient survived hospital discharge. Potentially reversible causes were detected in 15 cases (9.9%), and four of them survived to hospital discharge. Cardiac activity on first scan was associated with ROSC (OR: 6.86, 95%CI: 2.92-16.09; p < 0.001), survival to hospital admission (OR: 17.80, 95%CI: 3.95-80.17; p < 0.001), and survival to hospital discharge (OR: 17.35, 95%CI: 2.02-148.92; p = 0.001).

CONCLUSION

 In non-traumatic cardiac arrest patients with non-shockable rhythms, bedside US is of great importance in predicting ROSC. The presence of pulseless electrical activity (PEA) rhythm and cardiac activity on initial US were associated with ROSC, survival to hospital admission, and hospital discharge. When the cardiac standstill duration increased to six minutes, no patient survived hospital discharge.

Echocardiography does not prolong peri-shock pause in cardiopulmonary resuscitation using the COACH-RED protocol with non-expert sonographers in simulated cardiac arrest

OBJECTIVE

Focused echocardiography during peri-shock pause (PSP) can prognosticate and detect reversible causes in cardiac arrest but minimising interruptions to chest compressions improves outcome. The COACH-RED protocol was adapted from the COACHED protocol to systematically incorporate echocardiography into rhythm check without prolonging PSP beyond the recommended 10 s. The primary objective of this study was to test the feasibility of emergency nurses learning to perform all roles in the COACH-RED protocol. PSP duration and change in participant confidence were secondary outcomes.

METHODS

After an initial two-hour workshop, five ALS-trained nurses were assessed for the correct use of COACH-RED protocol, without critical error, in three simulated cardiac arrest scenarios of four cycles each. Assessments were repeated on days 7 and 35. On day 35, three COACHED scenarios were also assessed for comparison. Participant roles per scenario and cardiac rhythm per cycle were randomised. Participants completed questionnaires on their confidence levels. Sessions were videotaped for accurate measurement of PSP duration and results tabulated for simple comparison. Statistical analysis was not performed due to small sample size.

RESULTS

There were no critical errors, two minor team-leading errors and two minor echosonography errors. Minor errors occurred in separate scenarios resulting in a 100% pass rate overall by predetermined criteria. Echocardiographic recordings were 100% adequate. Overall median PSP was 9.35 s for COACH-RED and 6.94 s for COACHED. Sub-group analysis of COACH-RED revealed median PSP 10.80 s in shockable rhythms and 8.74 s (∼2 s less) in non-shockable rhythms. Mean participant confidence in performing COACH-RED improved from 1.6 to 4.6, on a 5-point scale.

CONCLUSION

The COACH-RED protocol can be effectively performed by ALS-trained nurses, in all roles of this protocol, including echocardiography, in a simulated environment, after a single training session. Using this protocol, focused echocardiography does not prolong PSP beyond 10 s.

Adult Advanced Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations

This 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations for advanced life support includes updates on multiple advanced life support topics addressed with 3 different types of reviews. Topics were prioritized on the basis of both recent interest within the resuscitation community and the amount of new evidence available since any previous review. Systematic reviews addressed higher-priority topics, and included double-sequential defibrillation, intravenous versus intraosseous route for drug administration during cardiac arrest, point-of-care echocardiography for intra-arrest prognostication, cardiac arrest caused by pulmonary embolism, postresuscitation oxygenation and ventilation, prophylactic antibiotics after resuscitation, postresuscitation seizure prophylaxis and treatment, and neuroprognostication. New or updated treatment recommendations on these topics are presented. Scoping reviews were conducted for anticipatory charging and monitoring of physiological parameters during cardiopulmonary resuscitation. Topics for which systematic reviews and new Consensuses on Science With Treatment Recommendations were completed since 2015 are also summarized here. All remaining topics reviewed were addressed with evidence updates to identify any new evidence and to help determine which topics should be the highest priority for systematic reviews in the next 1 to 2 years.

Novel 4W (When-Where-What-What) Approach of Training Point-of-Care Ultrasound (POCUS) Application in Resuscitation With High-Fidelity Simulator

Aim

Point-of-care ultrasound (POCUS) is a valuable tool in anesthesiology used for evaluating and managing cardiopulmonary pathology. Implications of this modality are extensive. Seamless integration into advanced cardiac life support (ACLS) has potential to improve resuscitation outcomes, and there is growing impetus for its implementation during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. However, it remains underutilized largely due to limited training. We use high-fidelity simulation and a novel 4W approach (when to apply POCUS, where to place the ultrasound probe, what images mean, what to do next) to incorporate this technique into resuscitation training. This study aims to evaluate the efficacy of a novel 4W POCUS approach for training anesthesiology residents in the setting of resuscitation.

Methods

Our approach teaches learners when and where to implement POCUS, how to interpret their findings, and how to apply these findings in a clinical setting. Learners apply this method in high-fidelity simulation to diagnose and treat cardiopulmonary pathologies. Assessments were administered before and after training to evaluate efficacy.

Results

Post-test improvements were appreciated across all residency classes (n = 23), with achieved significance of P < 0.001 in the first-year clinical anesthesia class (CA-1) and P = 0.02 in the second-year clinical anesthesia class (CA-2). Performance was further subdivided into five categories: resuscitation integration, lung ultrasound, transthoracic echo, disease recognition, and treatment. Post-test scores also improved in each category, with lung ultrasound being the most significant improvement (P = 0.04).

Conclusions

Our initial data demonstrate the effectiveness of this approach to POCUS training. Performance is improved and learners are more likely to use POCUS in the future. The application of this method to larger sample sizes is an appropriate next step to demonstrate its utility.

Handheld ultrasound in training - The future is getting smaller!

Traditional ultrasound teaching is normally delivered using large, costly and often quite advanced cart-based systems. These carts are often large systems on wheels, usually limited to the departments that own them i.e. clinics, wards or radiology. Portability has been further improved by the development of laptop style systems, which are easier to wheel in-between patients/departments. In our experience and anecdotally, many of these systems can be intimidating to the novice and can lead to early attrition or poor uptake of ultrasound into clinical practice. Carts can also restrict the amount of training deliverable to practitioners, as they are limited in number due to cost and can take quite some time to boot up, reducing convenience. This dogma is being progressively changed with the advent of smaller handheld devices, some clearly within the financial grasps of most practitioners, and even to the point of medical schools offering students their own personal device.^1,2 This relative inexpensiveness can lead to the purchase of these devices for novelty and convenience, over need. Obvious caution is needed in these circumstances, but with increased ease of purchase, better availability and inbuilt simplicity, ultrasound learning can be seamlessly integrated into day-to-day practice. This review discusses how one of the most disruptive innovations in modern medicine is changing ultrasound from a classic imaging modality to become integrated as the fifth pillar of clinical examination, and how these new devices can serve as springboards to more advanced ultrasound training. In fact, within what has become a bigger area of clinical examination, things are getting smaller.