Echocardiography for prognostication during the resuscitation of intensive care unit patients with non-shockable rhythm cardiac arrest

Use of point-of-care ultrasound during cardiac arrest in the intensive care unit: A cross-sectional survey

BACKGROUND

There is growing interest in the use of point-of-care ultrasound during cardiac arrest, but few studies document its use in the intensive care unit.

OBJECTIVE

We hypothesised this may reflect a low prevalence of use of point-of-care ultrasound during cardiac arrest or negative attitudes towards its use. We aimed to determine the self-reported prevalence, attitudes towards, and barriers to use of point-of-care ultrasound during cardiac arrest in the intensive care unit.

METHODS

We conducted a web-based survey over 3 months (08/08/2022-06/11/2022), of intensive care unit consultants and registrars in Victoria, Australia. Descriptive and mixed-methods analyses of Likert-type and free-text answers were performed.

RESULTS

The response rate was 91/398 (22.8%), split evenly between consultants and registrars. There was a broad range of clinical and ultrasound experience. Only 22.4% (22/91) of respondents reported using point-of-care ultrasound 75-100% of the time during their management of cardiac arrest. Respondents rated the value they place in point-of-care ultrasound during cardiac arrest 3 (interquartile range: 3-4) and that of a "skilled operator" 4 ((interquartile range; 4-5) on a 5-point scale. Free-text analysis suggested exclusion of "tamponade" (40/80 [50%] comments) as the most valuable use-case and "skill" as a personal barrier (20/73 [27.4%] comments). Personal and departmental barriers were not rated highly, although registrars perceived "lack of a structured training program" as a barrier. Respondents were equivocal in the value they gave point-of-care ultrasound during cardiac arrest but saw greater value when conducted by a skilled operator.

CONCLUSIONS

Point-of-care ultrasound was reported to be infrequently used in cardiac arrest, mostly due to self-perceived skill and lack of a structured training program.

Early point-of-care echocardiography as a predictive factor for absence of return of spontaneous circulatory in out-of-hospital cardiac arrests: A multicentre observational study

INTRODUCTION

Early assessment of the prognosis of a patient in cardiac arrest during cardiopulmonary resuscitation is highly challenging. This study aims to evaluate the predictive outcome value of early point-of-care ultrasound (POCUS) in out-of-hospital settings.

METHODS

This observational, prospective, multicentre study's primary endpoint was the positive predictive value (PPV) of POCUS cardiac standstill within the first 12 min of advanced life support (ALS) initiation in determining the absence of return of spontaneous circulation (ROSC). A multivariate logistic regression model was constructed with adjustments for known predictive variables typically used in termination of resuscitation (TOR) rules.

RESULTS

A total of 293 patients were analysed, with a mean age of 66.6 ± 14.6 years, and a majority were men (75.8%). POCUS was performed on average 7.9 ± 2.6 min after ALS initiation. Among patients with cardiac standstill (72.4%), 16.0% achieved ROSC compared with 48.2% in those with visible cardiac motions. The PPV of early POCUS cardiac standstill for the absence of ROSC was 84.0%, 95% CI [78.3-88.6]. In multivariable analysis, only POCUS cardiac standstill (adjusted odds ratio [aOR] 3.89, 95% CI [1.86-8.17]) and end-tidal CO2 (ETCO2) value ≤37 mmHg (aOR 4.27, 95% CI [2.21-8.25]) were associated with the absence of ROSC.

CONCLUSION

Early POCUS cardiac standstill during CPR for out-of-hospital cardiac arrest was a reliable predictor of the absence of ROSC. However, its presence alone was not sufficient to determine the termination of resuscitation efforts.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03494153. Registered March 29, 2018.

Artificial intelligence-based evaluation of carotid artery compressibility via point-of-care ultrasound in determining the return of spontaneous circulation during cardiopulmonary resuscitation

AIM

This study introduces RealCAC-Net, an artificial intelligence (AI) system, to quantify carotid artery compressibility (CAC) and determine the return of spontaneous circulation (ROSC) during cardiopulmonary resuscitation.

METHODS

A prospective study based on data from a South Korean emergency department from 2022 to 2023 investigated carotid artery compressibility in adult patients with cardiac arrest using a novel AI model, RealCAC-Net. The data comprised 11,958 training images from 161 cases and 15,080 test images from 134 cases. RealCAC-Net processes images in three steps: TransUNet-based segmentation, the carotid artery compressibility measurement algorithm for improved segmentation and CAC calculation, and CAC-based classification from 0 (indicating a circular shape) to 1 (indicating high compression). The accuracy of the ROSC classification model was tested using metrics such as the dice similarity coefficient, intersection-over-union, precision, recall, and F1 score.

RESULTS

RealCAC-Net, which applied the carotid artery compressibility measurement algorithm, performed better than the baseline model in cross-validation, with an average dice similarity coefficient of 0.90, an intersection-over-union of 0.84, and a classification accuracy of 0.96. The test set achieved a classification accuracy of 0.96 and an F1 score of 0.97, demonstrating its efficacy in accurately identifying ROSC in cardiac arrest situations.

CONCLUSIONS

RealCAC-Net enabled precise CAC quantification for ROSC determination during cardiopulmonary resuscitation. Future research should integrate this AI-enhanced ultrasound approach to revolutionize emergency care.

Point-of-Care Ultrasound: A Vital Tool for Anesthesiologists in the Perioperative and Critical Care Settings

Point-of-care ultrasound (POCUS) is an essential skill in various specialties like anesthesiology, critical care, and emergency medicine. Anesthesiologists utilize POCUS for quick diagnosis and procedural guidance in perioperative and critical care settings. Key applications include vascular ultrasound for challenging venous and arterial catheter placements, gastric ultrasound for aspiration risk assessment, airway ultrasound, diaphragm ultrasound, and lung ultrasound for respiratory assessment. Additional utilities of POCUS can include multi-organ POCUS evaluation for undifferentiated shock or cardiac arrest, ultrasound-guided central neuraxial and peripheral nerve blocks, focused cardiac ultrasound, and novel applications such as venous excess ultrasound. This review highlights these POCUS applications in perioperative and intensive care and summarizes the latest evidence of their accuracy and limitations.

Machine learning model to predict evolution of pulseless electrical activity during in-hospital cardiac arrest

Background

During pulseless electrical activity (PEA) the cardiac mechanical and electrical functions are dissociated, a phenomenon occurring in 25-42% of in-hospital cardiac arrest (IHCA) cases. Accurate evaluation of the likelihood of a PEA patient transitioning to return of spontaneous circulation (ROSC) may be vital for the successful resuscitation.

The aim

We sought to develop a model to automatically discriminate between PEA rhythms with favorable and unfavorable evolution to ROSC.

Methods

A dataset of 190 patients, 120 with ROSC, were acquired with defibrillators from different vendors in three hospitals. The ECG and the transthoracic impedance (TTI) signal were processed to compute 16 waveform features. Logistic regression models where designed integrating both automated features and characteristics annotated in the QRS to identify PEAs with better prognosis leading to ROSC. Cross validation techniques were applied, both patient-specific and stratified, to evaluate the performance of the algorithm.

Results

The best model consisted in a three feature algorithm that exhibited median (interquartile range) Area Under the Curve/Balanced accuracy/Sensitivity/Specificity of 80.3(9.9)/75.6(8.0)/ 77.4(15.2)/72.3(16.4) %, respectively.

Conclusions

Information hidden in the waveforms of the ECG and TTI signals, along with QRS complex features, can predict the progression of PEA. Automated methods as the one proposed in this study, could contribute to assist in the targeted treatment of PEA in IHCA.

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.

Guidance for clinical practice using emergency and point-of-care ultrasonography

Owing to the miniaturization of diagnostic ultrasound scanners and their spread of their bedside use, ultrasonography has been actively utilized in emergency situations. Ultrasonography performed by medical personnel with focused approaches at the bedside for clinical decision-making and improving the quality of invasive procedures is now called point-of-care ultrasonography (POCUS). The concept of POCUS has spread worldwide; however, in Japan, formal clinical guidance concerning POCUS is lacking, except for the application of focused assessment with sonography for trauma (FAST) and ultrasound-guided central venous cannulation. The Committee for the Promotion of POCUS in the Japanese Association for Acute Medicine (JAAM) has often discussed improving the quality of acute care using POCUS, and the "Clinical Guidance for Emergency and Point-of-Care Ultrasonography" was finally established with the endorsement of JAAM. The background, targets for acute care physicians, rationale based on published articles, and integrated application were mentioned in this guidance. The core points include the fundamental principles of ultrasound, airway, chest, cardiac, abdominal, and deep venous ultrasound, ultrasound-guided procedures, and the usage of ultrasound based on symptoms. Additional points, which are currently being considered as potential core points in the future, have also been widely mentioned. This guidance describes the overview and future direction of ultrasonography for acute care physicians and can be utilized for emergency ultrasound education. We hope this guidance will contribute to the effective use of ultrasonography in acute care settings in Japan.

Role of point-of-care ultrasound in critical care and emergency medicine: update and future perspective

Point-of-care ultrasound (POCUS) is a rapidly developing technology that has the potential to revolutionize emergency and critical care medicine. The use of POCUS can improve patient care by providing real-time clinical information. However, appropriate usage and proper training are crucial to ensure patient safety and reliability. This article discusses the various applications of POCUS in emergency and critical care medicine, the importance of training and education, and the future of POCUS in medicine.

Differential diagnosis and cause-specific treatment during out-of-hospital cardiac arrest: a retrospective descriptive study

BACKGROUND

The cardiopulmonary resuscitation (CPR) guidelines recommend identifying and correcting the underlying reversible causes of out-of-hospital cardiac arrest (OHCA). However, it is uncertain how often these causes can be identified and treated. Our aim was to estimate the frequency of point of care ultrasound examinations, blood sample analyses and cause-specific treatments during OHCA.

METHODS

We performed a retrospective study in a physician-staffed helicopter emergency medical service (HEMS) unit. Data on 549 non-traumatic OHCA patients who were undergoing CPR at the arrival of the HEMS unit from 2016 to 2019 were collected from the HEMS database and patient records. We also recorded the frequency of ultrasound examinations, blood sample analyses and specific therapies provided during OHCA, such as procedures or medications other than chest compressions, airway management, ventilation, defibrillation, adrenaline or amiodarone.

RESULTS

Of the 549 patients, ultrasound was used in 331 (60%) and blood sample analyses in 136 (24%) patients during CPR. A total of 85 (15%) patients received cause-specific treatment, the most common ones being transportation to extracorporeal CPR and percutaneous coronary intervention (PCI) (n = 30), thrombolysis (n = 23), sodium bicarbonate (n = 17), calcium gluconate administration (n = 11) and fluid resuscitation (n = 10).

CONCLUSION

In our study, HEMS physicians deployed ultrasound or blood sample analyses in 84% of the encountered OHCA cases. Cause-specific treatment was administered in 15% of the cases. Our study demonstrates the frequent use of differential diagnostic tools and relatively infrequent use of cause-specific treatment during OHCA. Effect on protocol for differential diagnostics should be evaluated for more efficient cause specific treatment during OHCA.

Point-of-Care Ultrasound Compression of the Carotid Artery for Pulse Determination in Cardiopulmonary Resuscitation

AIM

To identify whether a novel pulse check technique, carotid artery compression using an ultrasound probe, can reduce pulse check times compared to manual palpation (MP).

METHODS

This prospective study was conducted in an emergency department between February and December 2021. A physician applied point-of-care ultrasound-carotid artery compression (POCUS-CAC) and assessed the carotid artery compressibility and pulsatility by probe compression during rhythm check time. Another clinician performed MP of the femoral artery. The primary outcome was the difference in the average time for pulse assessment between POCUS-CAC and MP. The secondary outcomes included the time difference in each pulse check between methods, the proportion of times greater than 5 s and 10 s, and the prediction of return of spontaneous circulation (ROSC) during ongoing chest compression.

RESULTS

25 cardiac arrest patients and 155 pulse checks were analyzed. The median (interquartile range) average time to carotid pulse identification per patient using POCUS-CAC was 1.62 (1.14-2.14) s compared to 3.50 (2.99-4.99) s with MP. In all 155 pulse checks, the POCUS-CAC time to determine ROSC was significantly shortened to 0.44 times the MP time (P < 0.001). The POCUS-CAC approach never exceeded 10 s, and the number of patients who required more than 5 s was significantly lower (5 vs. 37, P < 0.001). Under continuous chest compression, six pulse checks predicted the ROSC.

CONCLUSIONS

We found that emergency physicians could quickly determine pulses by applying simple POCUS compression of the carotid artery in cardiac arrest patients.

Point-of-Care Resuscitative Echocardiography Diagnosis of Intracardiac Thrombus during cardiac arrest (PREDICT Study): A retrospective, observational cohort study

Background

Point-of-care ultrasound (POCUS) has been previously studied in cardiac arrest, without definitive markers for futile resuscitation efforts identified. Intracardiac thrombus during cardiac arrest has not been systematically studied. Our objective was to describe the incidence of intracardiac thrombus and spontaneous echo contrast found during cardiac arrest.

Methods

A two hospital, retrospective, observational cohort study of 56 cardiac arrest patients who were assessed with POCUS (between January 1st, 2017 to April 30th, 2020). Eligible studies were reviewed for echocardiographic findings (e.g. presence of intracardiac thrombus or spontaneous echo contrast), baseline patient demographics, cardiac arrest-related data, and clinical outcomes. Primary outcome was in-hospital mortality.

Results

Fifty-six intra-arrest POCUS echocardiograms were identified (out of 738 out-of-hospital cardiac arrests). The median patient age was 63 years (interquartile range [IQR]: 51–72), with 25% female patients, and median Charlson Comorbidity Index score of 4 (IQR: 2–6). The incidence of intracardiac thrombus was 21 out of 56 patients (38%). Time-to-new thrombus formation during cardiac arrest was approximately 6 minutes (IQR: 2-–8). All patients with intracardiac thrombus during cardiac arrest had termination of resuscitation.

Conclusions

Intracardiac thrombus is potentially common during out-of-hospital cardiac arrests and was observed more frequently in those in whom termination of resuscitation was recommended. However, this is only hypothesis-generating at this time, and further study is required to determine if the presence of intracardiac thrombus may be used as a potential marker of resuscitation futility.

Influence of advanced life support response time on out-of-hospital cardiac arrest patient outcomes in Taipei

Background

The association between out-of-hospital cardiac arrest patient survival and advanced life support response time remained controversial. We aimed to test the hypothesis that for adult, non-traumatic, out-of-hospital cardiac arrest patients, a shorter advanced life support response time is associated with a better chance of survival. We analyzed Utstein-based registry data on adult, non-traumatic, out-of-hospital cardiac arrest patients in Taipei from 2011 to 2015.

Methods

Patients without complete data, witnessed by emergency medical technicians, or with response times of ≥ 15 minutes, were excluded. We used logistic regression with an exposure of advanced life support response time. Primary and secondary outcomes were survival to hospital discharge and favorable neurological outcomes (cerebral performance category ≤ 2), respectively. Subgroup analyses were based on presenting rhythms of out-of-hospital cardiac arrest, bystander cardiopulmonary resuscitation, and witness status.

Results

A total of 4,278 cases were included in the final analysis. The median advanced life support response time was 9 minutes. For every minute delayed in advanced life support response time, the chance of survival to hospital discharge would reduce by 7% and chance of favorable neurological outcome by 9%. Subgroup analysis showed that a longer advanced life support response time was negatively associated with the chance of survival to hospital discharge among out-of-hospital cardiac arrest patients with shockable rhythm and pulse electrical activity groups.

Conclusions

In non-traumatic, adult, out-of-hospital cardiac arrest patients in Taipei, a longer advanced life support response time was associated with declining odds of survival to hospital discharge and favorable neurologic outcomes, especially in patients presenting with shockable rhythm and pulse electrical activity.

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.

A Machine Learning Model for the Prognosis of Pulseless Electrical Activity during Out-of-Hospital Cardiac Arrest

Pulseless electrical activity (PEA) is characterized by the disassociation of the mechanical and electrical activity of the heart and appears as the initial rhythm in 20–30% of out-of-hospital cardiac arrest (OHCA) cases. Predicting whether a patient in PEA will convert to return of spontaneous circulation (ROSC) is important because different therapeutic strategies are needed depending on the type of PEA. The aim of this study was to develop a machine learning model to differentiate PEA with unfavorable (unPEA) and favorable (faPEA) evolution to ROSC. An OHCA dataset of 1921 5s PEA signal segments from defibrillator files was used, 703 faPEA segments from 107 patients with ROSC and 1218 unPEA segments from 153 patients with no ROSC. The solution consisted of a signal-processing stage of the ECG and the thoracic impedance (TI) and the extraction of the TI circulation component (ICC), which is associated with ventricular wall movement. Then, a set of 17 features was obtained from the ECG and ICC signals, and a random forest classifier was used to differentiate faPEA from unPEA. All models were trained and tested using patientwise and stratified 10-fold cross-validation partitions. The best model showed a median (interquartile range) area under the curve (AUC) of 85.7(9.8)% and a balance accuracy of 78.8(9.8)%, improving the previously available solutions at more than four points in the AUC and three points in balanced accuracy. It was demonstrated that the evolution of PEA can be predicted using the ECG and TI signals, opening the possibility of targeted PEA treatment in OHCA.

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.

Multimodal Algorithms for the Classification of Circulation States During Out-of-Hospital Cardiac Arrest

GOAL

Identifying the circulation state during out-of-hospital cardiac arrest (OHCA) is essential to determine what life-saving therapies to apply. Currently algorithms discriminate circulation (pulsed rhythms, PR) from no circulation (pulseless electrical activity, PEA), but PEA can be classified into true (TPEA) and pseudo (PPEA) depending on cardiac contractility. This study introduces multi-class algorithms to automatically determine circulation states during OHCA using the signals available in defibrillators.

METHODS

A cohort of 60 OHCA cases were used to extract a dataset of 2506 5-s segments, labeled as PR (1463), PPEA (364) and TPEA (679) using the invasive blood pressure, experimentally recorded through a radial/femoral cannulation. A multimodal algorithm using features obtained from the electrocardiogram, the thoracic impedance and the capnogram was designed. A random forest model was trained to discriminate three (TPEA/PPEA/PR) and two (PEA/PR) circulation states. The models were evaluated using repeated patient-wise 5-fold cross-validation, with the unweighted mean of sensitivities (UMS) and F ₁-score as performance metrics.

RESULTS

The best model for 3-class had a median (interquartile range, IQR) UMS and F ₁ of 69.0% (68.0-70.1) and 61.7% (61.0-62.5), respectively. The best two class classifier had median (IQR) UMS and F ₁ of 83.9% (82.9-84.5) and 76.2% (75.0-76.9), outperforming all previous proposals in over 3-points in UMS.

CONCLUSIONS

The first multiclass OHCA circulation state classifier was demonstrated. The method improved previous algorithms for binary pulse/no-pulse decisions.

SIGNIFICANCE

Automatic multiclass circulation state classification during OHCA could contribute to improve cardiac arrest therapy and improve survival rates.

Factors affecting outcomes in patients with cardiac arrest who receive target temperature management: The multi-center TIMECARD registry

BACKGROUND

Target temperature management (TTM) is a recommended therapy for patients after cardiac arrest (PCA). The TaIwan Network of Targeted Temperature ManagEment for CARDiac Arrest (TIMECARD) registry was established for PCA who receive TTM therapy in Taiwan. We aim to determine the variables that may affect neurologic outcomes in PCA who undergo TTM.

METHODS

We retrieved demographic variables, resuscitation variables, and cerebral performance category (CPC) scale score at hospital discharge from the TIMECARD registry. The primary outcome was a favorable neurologic outcome, defined as a CPC scale of 1 or 2 at discharge. A total of 540 PCA treated between January 2014 and September 2019 were identified from the registry. Univariate and multivariate analyses were performed to identify significant variables.

RESULTS

The mortality rate was 58.1% (314/540). Favorable neurologic outcomes were noted in 117 patients (21.7%). The factors significantly influencing the neurologic outcome (p < 0.05) were the presence of an initial shockable rhythm or pulseless electric activity, a witnessed cardiac-arrest event, bystander cardiopulmonary resuscitation, a smaller total dose of epinephrine, the diastolic blood pressure value at return of spontaneous circulation, a pre-arrest CPC score of 1, coronary angiography, new-onset seizure, and new-onset serious infection. Older patients and those with premorbid diabetes mellitus, chronic kidney disease, malignancy, obstructive lung disease, or cerebrovascular accident were more likely to have an unfavorable neurologic outcome.

CONCLUSIONS

In the TIMECARD registry, some PCA baseline characteristics, cardiac arrest events, cardiopulmonary resuscitation characteristics, and post-arrest management characteristics were significantly associated with neurologic outcomes.

Epinephrine plus chest compressions is superior to epinephrine alone in a hypoxia-induced porcine model of pseudo-pulseless electrical activity

Aim

Pseudo-pulseless electrical activity (pseudo-PEA) is a global hypotensive ischemic state with retained coordinated myocardial contractile activity and an organized ECG with no clinically detectable pulses. The role of standard external chest compressions (CPR) and its associated intrinsic hemodynamics remains unclear in the setting of pseudo-PEA. We undertook an experimental trial to compare epinephrine alone versus epinephrine with CPR in the treatment of pseudo-PEA.

Methods

Using a porcine model of hypoxic pseudo-PEA, we randomized 12 Yorkshire male swine to resuscitation with epinephrine only (control) (0.0015 mg/kg) versus epinephrine plus standard CPR (intervention). Animals who achieved return of spontaneous circulation (ROSC) were stabilized, fully recovered to hemodynamic and respiratory baseline, and rearrested up to 6 times. Primary outcome was ROSC defined as a sustained systolic blood pressure (SBP) of 60 mmHg for 2 min. Secondary outcomes included time to ROSC, coronary perfusion pressure (CoPP), and end-tidal carbon dioxide (ETCO₂).

Results

Among 47 events of pseudo-PEA in 12 animals, we observed significantly higher proportion of ROSC when treatment included CPR (14/21 – 67%) compared to epinephrine alone (4/26 – 15%) (p = 0.0007). CoPP, aortic pressures and ETCO₂ were significantly higher, and right atrial pressures were lower in the intervention group.

Conclusions

In a swine model of hypoxia-induced pseudo-PEA, epinephrine plus CPR was associated with improved intra-arrest hemodynamics and higher probability of ROSC. Thus, epinephrine plus CPR may be superior to epinephrine alone in the treatment of patients with pseudo-PEA.

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.

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.

Point-of-care cardiac ultrasound during cardiac arrest: a reliable tool for termination of resuscitation?

PURPOSE OF REVIEW

Point-of-care ultrasound (POCUS) is commonly used during cardiac arrest to screen for potential causes and to inform termination of resuscitation. However, unique biases and limitations in diagnostic and prognostic test accuracy studies lead to potential for misinterpretation. The present review highlights recent evidence regarding POCUS in cardiac arrest, guides the incorporation of POCUS into clinical management, and outlines how to improve the certainty of evidence.

RECENT FINDINGS

Multiple frameworks organize and direct POCUS during cardiac arrest. Although many are proofs of concept, several have been prospectively evaluated. Indirect evidence from undifferentiated shock suggests that POCUS offers better specificity than sensitivity as a diagnostic aid. The prognostic accuracy of POCUS during cardiac arrest to predict subsequent clinical outcomes is better characterized, but subject to unique biases and confounding. Low certainty direct evidence suggests that POCUS offers better specificity than sensitivity as a prognostic aid.

SUMMARY

POCUS findings might indicate a particular diagnosis or encourage the continuation of resuscitation, but absence of the same is not sufficient in isolation to exclude a particular diagnosis or cease resuscitation. Until the evidence to support POCUS during cardiac arrest is more certain, it is best characterized as a diagnostic and prognostic adjunct.

Updates in Cardiac Arrest Resuscitation

There are approximately 350,000 out-of-hospital cardiac arrests and 200,000 in-hospital cardiac arrests annually in the United States, with survival rates of approximately 5% to 10% and 24%, respectively. The critical factors that have an impact on cardiac arrest survival include prompt recognition and activation of prehospital care, early cardiopulmonary resuscitation, and rapid defibrillation. Advanced life support protocols are continually refined to optimize intracardiac arrest management and improve survival with favorable neurologic outcome. This article focuses on current treatment recommendations for adult nontraumatic cardiac arrest, with emphasis on the latest evidence and controversies regarding intracardiac arrest management.

Ultrasonic cardiogram and MiRNA-21 analysis of cardiac dysfunction in patients with cardiac arrest following cardiopulmonary resuscitation

PURPOSE

To explore correlations between the serum level of miRNA-21 expression and cardiac dysfunction severity after cardiopulmonary resuscitation (CPR) using ultrasonic cardiogram.

METHODS

Thirty-nine patients with cardiopulmonary arrest receiving successful CPR and forty-one healthy participants were recruited in the study. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and immunochemiluminometric assays was used to examine the serum miRNA-21 level and the concentration of cardiac troponins T and I, respectively. Indices of Electrocardiogram (ECG) and cardiac dysfunction measured by ultrasound of patients in the case group were used to assess cardiac function after CPR. Furthermore, the correlation between the serum level of miRNA-21 expression and severity of cardiac dysfunction was analyzed by Spearman correlation analysis.

RESULTS

As compared to the control group, the serum level of miRNA-21 expression, as well as cardiac troponin T and I levels in the case group were significantly higher (p = 0.000). The miRNA-21 expression level in the patients at IV grade of cardiac function were substantially higher than patients at III grade (p = 0.015). There was no significant difference in level of cardiac troponins T and I between patients at III grade and patients at IV grade (p > 0.05). Further, Spearman correlation analysis revealed that the level of miRNA-21 expression was negatively correlated with cardiac function index in the ultrasound imaging: E peak, E/A value, LVEF and LVEDD (r = 0.617, 0.535, 0.612, 0.573, P = 0.012, 0.009, 0.008, 0.011), but was positively correlated with the level of cardiac troponins T and I (r = 0.546,0.582, P = 0.006,0.007) and the severity of cardiac dysfunction (r = 0.859, p < 0.05).

CONCLUSION

The level of miRNA-21 is higher after CPR is closely related to the severity of cardiac dysfunction that is measured by ultrasound, suggesting that it may serve as a potential biomarker.

Prognostication with point-of-care echocardiography during cardiac arrest: A systematic review

AIM

To conduct a prognostic factor systematic review on point-of-care echocardiography during cardiac arrest to predict clinical outcomes in adults with non-traumatic cardiac arrest in any setting.

METHODS

We conducted this review per PRISMA guidelines and registered with PROSPERO (ID pending). We searched Medline, EMBASE, Web of Science, CINAHL, and the Cochrane Library on September 6, 2019. Two investigators screened titles and abstracts, extracted data, and assessed risks of bias using the Quality in Prognosis Studies (QUIPS) template. We estimated prognostic test performance (sensitivity and specificity) and measures of association (odds ratio). Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology evaluated the certainty of evidence.

RESULTS

In total, 15 studies were included. We found wide variation across studies in the definition of 'cardiac motion' and timing of sonographic assessment. Most studies were hindered by high risks of bias from prognostic factor measurement, outcome measurement, and lack of adjustment for other prognostic factors. Ultimately, heterogeneity and risk of bias precluded meta-analyses. We tabulated ranges of prognostic test performance and measures of association for 5 different combinations of definitions of 'cardiac motion' and sonographic timing, as well as other miscellaneous sonographic findings. Overall certainty of this evidence is very low.

CONCLUSIONS

The evidence for using point-of-care echocardiography as a prognostic tool for clinical outcomes during cardiac arrest is of very low certainty and is hampered by multiple risks of bias. No sonographic finding had sufficient and/or consistent sensitivity for any clinical outcome to be used as sole criterion to terminate resuscitation.

Transesophageal echocardiography (TEE) in the detection of intraoperative cardiac arrest: A case report

RATIONALE

Point-of-care ultrasound is widely used in patients with cardiac arrest, allowing for diagnosing, monitoring, and prognostication as well as assessing the effectiveness of the chest compressions. However, the detection of intraoperative cardiac arrest by Point-of-care ultrasound was rarely reported.

PATIENT CONCERNS

A 21-year-old male with Marfan syndrome which manifested Valsalva sinus aneurysms was admitted for aortic valve replacement. After endotracheal intubation, TEE transducer was inserted to evaluate the cardiac structure and function with different views. Severe aortic valve regurgitation was observed in the mid-esophageal aortic valve long and short axis view.

DIAGNOSIS

TEE showed that cardiac contraction was nearly stopped, the spontaneous echo contrast was obvious in the left ventricular and hardly any blood was pumped out from the heart despite the ECG showing normal sinus rhythm with HR 61 beats/min. Meanwhile, the IBP was dropped to 50/30 mm Hg.

INTERVENTIONS

Chest compressions were started immediately and epinephrine 100 μg was given intravenously. After 30 times of chest compressions, TEE showed that cardiac contractility increased and the stroke volume was improved in the TG SAX view.

OUTCOMES

The patient was discharged 18 days later in a stable condition.

LESSONS

Continuous echocardiography monitoring may be of particular value in forewarning and detecting cardiac arrest in high-risk patients.

Cardiac Thrombus Formation During Cardiopulmonary Resuscitation for Cardiac Arrest: Is It Time for Ultrasound-Enhanced Algorithms?

Current guidelines consider thrombosis as a potential (and reversible) cause of cardiorespiratory arrest (CA). However, cardiac thrombus formation (TF) is likely to be the consequence of the forward blood flow ceasing during cardiac standstill. We present the case of a young man who was hospitalized for infective endocarditis, complicated by multiorgan disease and sudden CA on the 5^th day. Prompt cardiopulmonary resuscitation (CPR) warranted a return of spontaneous circulation in 16 min but, unexpectedly, a TF was recognized in the right atrium at echocardiography. The blood clot resolved with rapid administration of endovenous heparin and continued chest compressions. Even though cardiac ultrasound is not ready for a routine use during CPR, the present study confirms a key role in the management of CA patients.

Clinical Guidance for Point-of-Care Ultrasound in the Emergency and Critical Care Areas after Implementing Insurance Coverage in Korea

Point-of-care ultrasound (POCUS) is a useful tool that is widely used in the emergency and intensive care areas. In Korea, insurance coverage of ultrasound examination has been gradually expanding in accordance with measures to enhance Korean National Insurance Coverage since 2017 to 2021, and which will continue until 2021. Full coverage of health insurance for POCUS in the emergency and critical care areas was implemented in July 2019. The National Health Insurance Act classified POCUS as a single or multiple-targeted ultrasound examination (STU vs. MTU). STU scans are conducted of one organ at a time, while MTU includes scanning of multiple organs simultaneously to determine each clinical situation. POCUS can be performed even if a diagnostic ultrasound examination is conducted, based on the physician's decision. However, the Health Insurance Review and Assessment Service plans to monitor the prescription status of whether the POCUS and diagnostic ultrasound examinations are prescribed simultaneously and repeatedly. Additionally, MTU is allowed only in cases of trauma, cardiac arrest, shock, chest pain, and dyspnea and should be performed by a qualified physician. Although physicians should scan all parts of the chest, heart, and abdomen when they prescribe MTU, they are not required to record all findings in the medical record. Therefore, appropriate prescription, application, and recording of POCUS are needed to enhance the quality of patient care and avoid unnecessary cut of medical budget spending. The present article provides background and clinical guidance for POCUS based on the implementation of full health insurance coverage for POCUS that began in July 2019 in Korea.

The Value of Focused Echocardiography During Cardiac Arrest

Cardiac arrest is the absence of a centrally palpable pulse and no respiratory effort in an unresponsive patient. This often-lethal medical condition affects hundreds of thousands of people in the United States alone every year. Immediate intervention is crucial to provide the patient with any chance of survival. Advanced cardiac life support (ACLS) is the cornerstone therapy for cardiac arrest. Increased awareness and proper identification of life-threatening arrhythmias is critical, as it may lead to prompt medical treatment and improved mortality. The use of focused echocardiography, during a cardiac arrest, has been a developing area of interest over the past several years. The specific aim of this literature review was to emphasize the role of a focused echocardiogram and the valuable information that can be provided during a cardiac arrest.

The use of handheld ultrasound devices: a position statement of the European Association of Cardiovascular Imaging (2018 update)

Recent technological advances in echocardiography, with progressive miniaturization of ultrasound machines, have led to the development of handheld ultrasound devices (HUD). These devices, no larger than some mobile phones, can be used to perform partial, focused exams as an extension to the physical examination. The European Association of Cardiovascular Imaging (EACVI) acknowledges that the dissemination of appropriate HUD use is inevitable and desirable, because of its potential impact on patient management. However, as a scientific society of cardiac imaging, our role is to provide guidance in order to optimize patient benefit and minimize drawbacks from inappropriate use of this technology. This document provides updated recommendations for the use of HUD, including nomenclature, appropriateness, indications, operators, clinical environments, data management and storage, educational needs, and training of potential users. It also addresses gaps in evidence, controversial issues, and future technological developments.

Knowledge and experience of cardiopulmonary resuscitation among cardiologists in clinical practice: A multicenter cross-sectional study

OBJECTIVE

This study aimed to investigate the theoretical knowledge and clinical experience of cardiopulmonary resuscitation (CPR) among Turkish cardiologists according to the recommendations of the 2015 European Resuscitation Council (ERC) guidelines.

METHODS

A total of 120 cardiologists from 14 different medical centers (six university and eight research-education hospitals) in İstanbul were included in the study. The questionnaire consisting of 29 open-ended and multiple choice questions on CPR was used and validated based on the ERC guidelines published in 2015. The percentage of correct answers was calculated for each participant.

RESULTS

Of the 120 cardiologists included in this study, 108 (90%) accepted the participation, and the median percentage of correct answers for theoretical questions was 53% (38-72). The percentage of correct answers for interventional cardiologists (48%, n=52) was significantly higher [60% (50-66) vs. 46% (38-52), p<0.001]. Regarding the type of medical centers, no statictical difference was found in terms of theoretical knowledge on CPR [57% (50-72) university hospitals vs. 49% (41-57) research-education hospitals, p=0.160). Peri-arrest transthoracic echocardiography was used in 71% of cases. The ratio of participants who had received an advanced cardiac life support course in the preceding year was only 19% (n=20), and those participants had a significantly higher score regarding the CPR theoretical knowledge questions [68% (54-70) vs. 46% (38-51), p<0.001].

CONCLUSION

The theoretical knowledge of cardiologists on CPR is not satisfactory according to the 2015 ERC guidelines. An increased frequency of CPR training courses may improve this result.

The incidence of cardiac arrest in the intensive care unit: A systematic review and meta-analysis

The incidence of cardiac arrest in the intensive care unit (ICU-CA) has not been widely reported. We undertook a systematic review and meta-analysis of studies reporting the incidence of cardiac arrest in adult, general intensive care units. The review was prospectively registered with PROSPERO (CRD42017079717). The search identified 7550 records, which included 20 relevant studies for qualitative analysis and 16 of these were included for quantitative analyses. The reported incidence of ICU-CA was 22.7 per 1000 admissions (95% CI: 17.4-29.6) with survival to hospital discharge of 17% (95% CI: 9.5-28.5%). We estimate that at least 5446 patients in the UK have a cardiac arrest after ICU admission. There are limited data and significant variation in the incidence of ICU-CA and efforts to synthesise these are limited by inconsistent reporting. Further prospective studies with standardised process and incidence measures are required to define this important patient group.

Focus cardiac ultrasound core curriculum and core syllabus of the European Association of Cardiovascular Imaging

There is a growing trend of using ultrasound examination of the heart as a first-line diagnostic tool for initial patient evaluation in acute settings. Focus cardiac ultrasound (FoCUS) is a standardized but restricted cardiac ultrasound examination that may be undertaken by a range of medical professionals with diverse backgrounds. The intention of this core curriculum and syllabus is to define a unifying framework for educational and training processes/programmes that should result in competence in FoCUS for various medical professionals dealing with diagnostics and treatment of cardiovascular emergencies. The European Association of Cardiovascular Imaging prepared this document in close cooperation with representatives of the European Society of Anaesthesiology, the European Association of Cardiothoracic Anaesthesiology, the Acute Cardiovascular Care Association of the European Society of Cardiology and the World Interactive Network Focused On Critical Ultrasound. It aims to provide the key principles and represents a guide for teaching and training of FoCUS. We offer this document to the emergency and critical care community as a reference outline for teaching materials and courses related to FoCUS, for promoting teamwork and encouraging the development of the field.

Novel patterns of left ventricular mechanical activity during experimental cardiac arrest in pigs

We conducted an experimental study to evaluate the presence of coordinated left ventricular mechanical myocardial activity (LVMA) in two types of experimentally induced cardiac arrest: ventricular fibrillation (VF) and pulseless electrical activity (PEA). Twenty anesthetized domestic pigs were randomized 1:1 either to induction of VF or PEA. They were left in nonresuscitated cardiac arrest until the cessation of LVMA and microcirculation. Surface ECG, presence of LVMA by transthoracic echocardiography and sublingual microcirculation were recorded. One minute after induction of cardiac arrest, LVMA was identified in all experimental animals. In the PEA group, rate of LVMA was of 106+/-12/min. In the VF group, we identified two patterns of LVMA. Six animals exhibited contractions of high frequency (VFhigh group), four of low frequency (VFlow group) (334+/-12 vs. 125+/-32/min, p<0.001). A time from cardiac arrest induction to asystole (19.2+/-7.2 vs. 7.3+/-2.2 vs. 8.3+/-5.5 min, p=0.003), cessation of LVMA (11.3+/-5.6 vs. 4.4+/-0.4 vs. 7.4+/-2.9 min, p=0.027) and cessation of microcirculation (25.3+/-12.6 vs. 13.4+/-2.4 vs. 23.2+/-8.7 min, p=0.050) was significantly longer in VFlow group than in VFhigh and PEA group, respectively. Thus, LVMA is present in both VF and PEA type of induced cardiac arrest and moreover, VF may exhibit various patterns of LVMA.

The predictive value of bedside ultrasound to restore spontaneous circulation in patients with pulseless electrical activity: A systematic review and meta-analysis

Background

The prognosis of pulseless electrical activity is dismal. However, it is still challengable to decide when to terminate or continue resuscitation efforts. The aim of this study was to determine whether the use of bedside ultrasound (US) could predict the restoration of spontaneous circulation (ROSC) in patients with pulseless electrical activity (PEA) through the identification of cardiac activity.

Methods

This was a systematic review and meta-analysis of studies that used US to predict ROSC. A search of electronic databases (Cochrane Central, MEDLINE, EMBASE) was conducted up to June 2017, and the assessment of study quality was performed with the Newcastle-Ottawa Scale. Statistical analysis was performed with Review Manager 5.3 and Stata 12.

Results

Eleven studies that enrolled a total of 777 PEA patients were included. A total of 230 patients experienced ROSC. Of these, 188 had sonographically identified cardiac activity (pseudo-PEA). A meta-analysis showed that PEA patients with cardiac activity on US were more likely to obtain ROSC compared to those with cardiac standstill: risk ratio (RR) = 4.35 (95% confidence interval [CI], 2.20–8.63; p<0,00001) with significant statistical heterogeneity (I² = 60%). Subgroup analyses were conducted: US evaluation using only on the subxiphoid view: RR = 1.99 (95% CI, 0.79–5.02; p = 0.15); evaluation using various views: RR = 4.09 (95% CI,2.70–6.02; p<0.00001).

Conclusions

In cardiac arrest patients who present with PEA, bedside US has an important role in predicting ROSC. The presence of cardiac activity in PEA patients may encourage more aggressive resuscitation.

Point-of-care ultrasound in cardiopulmonary resuscitation: a concise review

Point-of-care ultrasound (POCUS) is a widely used tool in critical care areas, allowing for the performance of accurate diagnoses and thus enhancing the decision-making process. Every major organ or system can be safely evaluated with POCUS. In that respect, the utility of POCUS in cardiac arrest is gaining interest. In this article, we will review the actual role of ultrasound in cardiac arrest and the main POCUS protocols focused to this scenario as well as discuss the potential role of POCUS in monitoring the efficacy of the chest compressions.