Ultrasound in Cardiopulmonary Arrest and Resuscitation: Constructing Comprehensive Implementation Frameworks in High-Risk Settings.

OBJECTIVES: Information obtained from point-of-care ultrasound during cardiopulmonary arrest and resuscitation (POCUS-CA) can be used to identify underlying pathophysiology and provide life-sustaining interventions. However, integration of POCUS-CA into resuscitation care is inconsistent. We used expert consensus building methodology to help identify discrete barriers to clinical integration. We subsequently applied implementation science frameworks to generate generalizable strategies to overcome these barriers. MEASURES AND MAIN RESULTS: Two multidisciplinary expert working groups used KJ Reverse-Merlin consensus building method to identify and characterize barriers contributing to failed POCUS-CA utilization in a hypothetical future state. Identified barriers were organized into affinity groups. The Center for Implementation Research (CFIR) framework and Expert Recommendations for Implementing Change (CFIR-ERIC) tool were used to identify strategies to guide POCUS-US implementation. RESULTS: Sixteen multidisciplinary resuscitation content experts participated in the working groups and identified individual barriers, consolidated into 19 unique affinity groups that mapped 12 separate CFIR constructs, representing all 5 CFIR domains. The CFIR-ERIC tool identified the following strategies as most impactful to address barriers described in the affinity groups: identify and prepare champions, conduct local needs assessment, conduct local consensus discussions, and conduct educational meetings. CONCLUSIONS: KJ Reverse-Merlin consensus building identified multiple barriers to implementing POCUS-CA. Implementation science methodologies identified and prioritized strategies to overcome barriers and guide POCUS-CA implementation across diverse clinical settings.

Timing of Initiation of Extracorporeal Membrane Oxygenation Support and Outcomes Among Patients With Cardiogenic Shock.

BACKGROUND: Venoarterial extracorporeal membrane oxygenation (ECMO) provides full hemodynamic support for patients with cardiogenic shock, but optimal timing of ECMO initiation remains uncertain. We sought to determine whether earlier initiation of ECMO is associated with improved survival in cardiogenic shock. METHODS AND RESULTS: We analyzed adult patients with cardiogenic shock who received venoarterial ECMO from the international Extracorporeal Life Support Organization (ELSO) registry from 2009 to 2019, excluding those cannulated following an operation. Multivariable logistic regression evaluated the association between time from admission to ECMO initiation and in-hospital death. Among 8619 patients (median, 56.7 [range, 44.8-65.6] years; 33.5% women), the median duration from admission to ECMO initiation was 14 (5-32) hours. Patients who had ECMO initiated within 24 hours (n=5882 [68.2%]) differed from those who had ECMO initiated after 24 hours, with younger age, more preceding cardiac arrest, and worse acidosis. After multivariable adjustment, patients with ECMO initiated >24 hours after admission had higher risk of in-hospital death (adjusted odds ratio, 1.20 [95% CI, 1.06-1.36]; P=0.004). Each 12-hour increase in the time from admission to ECMO initiation was incrementally associated with higher adjusted in-hospital mortality rate (adjusted odds ratio, 1.06 [95% CI, 1.03-1.10]; P<0.001). The association between longer time to ECMO and worse outcomes appeared stronger in patients with lower shock severity. CONCLUSIONS: Longer delays from admission to ECMO initiation were associated with higher a mortality rate in a large-scale, international registry. Our analysis supports optimization of door-to-support time and the avoidance of inappropriately delayed ECMO initiation.

A proposed rescue transesophageal echocardiographic protocol for anesthetized dogs.

OBJECTIVE: To describe the acquisition and pitfalls of a 3-view transesophageal echocardiography (TEE) protocol in anesthetized, dorsally recumbent dogs. ANIMALS: 8 beagles, 1 to 2 years old, 7.4 to 11.2 kg. METHODS: Dogs were anesthetized, mechanically ventilated, and placed in dorsal recumbency. A TEE probe was advanced, and 3 views were performed: midesophageal 4-chamber and long axis (ME 4C and ME LAX) and caudal esophageal short axis (CE SAX) at the level of the papillary muscles. Probe insertion depth, flexion, omniplane angle, and image acquisition time were recorded. Two observers assessed 24 video clips each and identified anatomical structures. RESULTS: The ME 4C and ME LAX were obtained at 35 (30 to 40) cm insertion depth, omniplane at 0° and 103° (90 to 116), respectively. Views were obtained in ≤30 seconds once the TEE was in the cervical esophagus. Left-sided structures were identified in all cases, whereas right-sided structures were not always simultaneously obtained in the ME 4C, requiring further probe manipulation. All structures were identified on ME LAX. CE SAX was obtained at 40 (35 to 45) cm, omniplane at 0°, and in 15 (10 to 90) seconds. A true SAX view (circular left ventricle at the level of papillary muscles) could not be obtained in all dogs. CLINICAL RELEVANCE: A 3-view TEE protocol using core views as those described in humans may be applicable to dogs under general anesthesia and in dorsal recumbency. The CE SAX view at the level of the papillary muscles appears more difficult to obtain with consistency than midesophageal views.

Resuscitative transesophageal echocardiography in emergency departments in the United States and Canada: A cross-sectional survey.

INTRODUCTION: Over the past two decades, transesophageal echocardiography (TEE) has been used with increasing frequency to evaluate critically ill patients outside of traditional settings. The purpose of this study was to characterize the number of programs, users, practice characteristics, training and competency requirements and barriers for the current use of resuscitative transesophageal echocardiography (TEE) in Emergency Departments (EDs) in the United States and Canada. METHODS: A closed internet-based, cross-sectional, point-prevalence survey was administered via email to 120 program directors of emergency ultrasound fellowships (EUSF) and 43 physicians from EDs without EUSF from the United States and Canada. RESULTS: Ninety-eight percent of surveyed participants responded. Twenty percent of respondents reported having active resuscitative TEE programs. The majority of participating hospitals (70%) were academic centers with residency programs. A total of 33 programs reported using resuscitative TEE in their ED and of those, 82% were programs with EUSF. Most programs performing TEE (79%) had less than five attending physicians performing TEE. Evaluation of patients during resuscitation from cardiac arrest (100%) and post-arrest care (76%) are the two most frequent indications for TEE in the ED. The most common core elements of resuscitative TEE protocols used are: assessment of left ventricular (LV) systolic function (97%), assessment of right ventricular (RV) function (88%), evaluation of pericardial effusion / tamponade (52%). All programs reported using formal didactics in their training programs, 94% reported using high-fidelity simulation, and 79% live scanning of patients. Financial concerns were the most common barrier use of TEE in the ED (58%), followed by maintenance of equipment (30%), and credentialing/privileges (30%). CONCLUSIONS: This study provides a snapshot of the practice of resuscitative TEE in EDs in the United States and Canada revealing the existence of 33 programs using this emerging modality in the care of critically ill patients.

The Latest in Resuscitation Research: Highlights From the 2022 American Heart Association's Resuscitation Science Symposium.

BACKGROUND: Every year the American Heart Association's Resuscitation Science Symposium (ReSS) brings together a community of international resuscitation science researchers focused on advancing cardiac arrest care. METHODS AND RESULTS: The American Heart Association's ReSS was held in Chicago, Illinois from November 4th to 6th, 2022. This annual narrative review summarizes ReSS programming, including awards, special sessions and scientific content organized by theme and plenary session. CONCLUSIONS: By exploring both the science of resuscitation and important related topics including survivorship, disparities, and community-focused programs, this meeting provided important resuscitation updates.

Pulmonary Artery Pressures and Mortality during VA ECMO: An ELSO Registry Analysis.

Background: Systemic hemodynamics and specific ventilator settings have been shown to predict survival during venoarterial extracorporeal membrane oxygenation (VA ECMO). While these factors are intertwined with right ventricular (RV) function, the independent relationship between RV function and survival during VA ECMO is unknown. Objectives: To identify the relationship between RV function with mortality and duration of ECMO support. Methods: Cardiac ECMO runs in adults from the Extracorporeal Life Support Organization (ELSO) Registry between 2010 and 2022 were queried. RV function was quantified via pulmonary artery pulse pressure (PAPP) for pre-ECMO and on-ECMO periods. A multivariable model was adjusted for Society for Cardiovascular Angiography and Interventions (SCAI) stage, age, gender, and concurrent clinical data (i.e., pulmonary vasodilators and systemic pulse pressure). The primary outcome was in-hospital mortality. Results: A total of 4,442 ECMO runs met inclusion criteria and had documentation of hemodynamic and illness severity variables. The mortality rate was 55%; non-survivors were more likely to be older, have a worse SCAI stage, and have longer pre-ECMO endotracheal intubation times (P < 0.05 for all) than survivors. Improving PAPP from pre-ECMO to on-ECMO time (Δ PAPP) was associated with reduced mortality per 10 mm Hg increase (OR: 0.91 [95% CI: 0.86-0.96]; P=0.002). Increasing on-ECMO PAPP was associated with longer time on ECMO per 10 mm Hg (Beta: 15 [95% CI: 7.7-21]; P<0.001). Conclusions: Early improvements in RV function from pre-ECMO values were associated with mortality reduction during cardiac ECMO. Incorporation of Δ PAPP into risk prediction models should be considered.

Transesophageal Echocardiography in Patients in Cardiac Arrest: The Heart and Beyond.

Point of care ultrasound involves different ultrasound modalities and is useful to assist management in emergent clinical situations such as cardiac arrest. The use of point of care ultrasound in cardiac arrest has mainly been described using transthoracic echocardiography as a diagnostic and as a prognostic tool. However, cardiac evaluation using transthoracic echocardiography might be challenging because of patient-related or technical factors. Furthermore, its use during pulse check pauses has been associated with delays in chest compression resumption. Transesophageal echocardiography (TEE) overcomes these limitations by providing reliable and continuous imaging of the heart without interfering with cardiopulmonary resuscitation. In this narrative review we describe the role of TEE during cardiopulmonary resuscitation in 4 different applications: (1) chest compression quality feedback; (2) rhythm characterization; (3) diagnosis of reversible causes; and (4) procedural guidance. Considering its limitations, we propose an algorithm for the integration of TEE in patients with cardiac arrest with a focus on these 4 applications and extend its use to extracardiac applications.

Critical Care Echocardiography: A Primer for the Nephrologist.

Critical care echocardiography (CCE) refers to the goal-directed use of transthoracic or transesophageal echocardiography and represents one of the most common applications of critical care ultrasound. CCE can be performed at the point of care, is easily repeated following changes in clinical status, and does not expose the patient to ionizing radiation. Nephrologists who participate in the care of patients in the intensive care unit will regularly encounter CCE as part of the decision-making and bedside management of ICU patients. The four primary indications for CCE are the characterization of shock, evaluation of preload tolerance, evaluation of volume responsiveness, and serial hemodynamic assessment to evaluate response to therapeutic interventions. This article provides an overview of the anatomical structures that are routinely assessed in basic CCE, describes how these findings are incorporated into the clinical assessment of critically ill patients, and introduces some common applications of advanced CCE.

Transoesophageal echocardiography in cardiac arrest: A systematic review.

AIMS: To identify, appraise and synthesize all available clinical evidence to evaluate the diagnostic role of transoesophageal echocardiography (TEE) during resuscitation of in-hospital (IHCA) and out-of-hospital cardiac arrest (OHCA) in the identification of reversible causes of cardiac arrest and cardiac contractility. METHODS: We conducted a systematic review following PRISMA guidelines. Medline, EMBASE, Web of Science Core Collection, Proquest Dissertations, Open Grey, CDSR, Cochrane Central, Cochrane Clinical Answers, and the clinicaltrials.gov registry were searched for eligible studies. Studies involving adult patients, with non-traumatic cardiac arrest in whom TEE was used for intra-arrest evaluation, were included. Case studies and case series, animal studies, reviews, guidelines and editorials were excluded. The QUADAS-2 tool was used for quality assessment of all studies. RESULTS: Eleven studies with a total of 358 patients were included. Four studies involved perioperative IHCA, three involved OHCA, and four were mixed population settings. Overall, the risk of bias in the selected studies was either high or unclear due to evidence or lack of information. In all 11 studies, TEE allowed the identification of reversible causes of arrest. We found significant heterogeneity in the criteria used to interpret findings, TEE protocol used, and timing of TEE. CONCLUSION: Due to heterogeneity of studies, small sample size and inconsistent reference standard, the evidence for TEE in cardiac arrest resuscitation is of low certainty and is affected by a high risk of bias. Further studies are needed to better understand the true diagnostic accuracy of TEE in identifying reversible causes of arrest and cardiac contractility.

Development and validation of a novel image quality rating scale for echocardiography during cardiac arrest.

OBJECTIVE: Research into echocardiography (echo) during cardiac arrest has suffered from methodological flaws that limit aggregation of findings. We developed and validated a novel image rating scale for qualitative analysis of echo images obtained during resuscitation. METHODS: A novel 5-point ordinal rating scale was developed and validated using recorded echo images from 145 consecutive cardiac arrest patients. Recorded echo images were reviewed in a blinded fashion by investigators experienced in cardiac arrest echo, and image quality was rated using this scale. Cardiac activity was subsequently classified as no activity, disorganized activity and organized activity. The primary outcome was inter-rater agreement using the image quality rating scale. Secondary outcome was the qualitative evaluation of the type of cardiac activity. RESULTS: A total of 235 ultrasounds were analyzed by study investigators using the image quality rating scale. The overall image quality agreement between reviewers using the scale was good with a weighted kappa of 0.65. Agreement for image quality in subxyphoid images was greater than in parasternal images (0.65-0.52). Echo analysis of cardiac activity showed no activity (33%), disorganized activity (18%), and organized activity (49%). Agreement was great for presence or absence of "cardiac activity" and "organized cardiac activity" with a kappa of 0.84 and 0.78. CONCLUSIONS: A novel image quality rating scale for echo during cardiac arrest demonstrates substantial agreement between reviewers. Agreement regarding the presence or absence, as well as the organization of cardiac activity was substantial.

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.

Quantitative characterization of left ventricular function during pulseless electrical activity using echocardiography during out-of-hospital cardiac arrest.

BACKGROUND: Several prospective studies have demonstrated that the echocardiographic detection of any myocardial activity during PEA is strongly associated with higher rates of return of spontaneous circulation (ROSC). We hypothesized that PEA represents a spectrum of disease in which not only the presence of myocardial activity, but more specifically that the degree of left ventricular (LV) function would be a predictor of outcomes. The purpose of this study was to retrospectively assess the association between LV function and outcomes in patients with OHCA. MATERIALS AND METHODS: Using prospectively obtained data from an observational cohort of patients receiving focused echocardiography during cardiopulmonary resuscitation (CPR) in the Emergency Department (ED) setting, we analyzed 312 consecutive subjects with available echocardiography images with initial rhythm of PEA. We used left ventricular systolic fractional shortening (LVFS), a unidimensional echocardiographic parameter to perform the quantification of LV function during PEA. Regression analyses were performed independently to evaluate for relationships between LVFS and a primary outcome of ROSC and secondary outcome of survival to hospital admission. We analyzed LVFS both as a continuous variable and as a categorial variable using the quartiles and the median to perform multiple different comparisons and to illustrate the relationship of LVFS and outcomes of interest. We performed survival analysis using Cox proportional hazards model to evaluate the hazard corresponding to length of resuscitation. RESULTS: We found a positive association between LVFS and the primary outcome of ROSC (OR 1.04, 95%CI 1.01-1.08), but not with the secondary outcome of survival to hospital admission (OR 1.02, 95%CI 0.96-1.08). Given that the relationship was not linear and that we observed a threshold effect in the relationship between LVFS and outcomes, we performed an analysis using quartiles of LVFS. The predicted probability of ROSC was 75% for LVFS between 23.4-96% (fourth quartile) compared to 47% for LVFS between 0-4.7% (first quartile). The hazard of not achieving ROSC was significantly greater for subjects with LVFS below the median (13.1%) compared to the subgroup with LVFS greater than 13.1% (p < 0.05), with the separation of the survival curves occurring at approximately 40 min of resuscitation duration. CONCLUSIONS: Left ventricular function measured by LVFS is positively correlated with higher probability of ROSC and may be associated with higher chances of survival in patients with PEA arrest.

Rapid response system adaptations at 40 US hospitals during the COVID-19 pandemic.

BACKGROUND: Management of patients with acute deterioration from novel coronavirus disease of 2019 (COVID-19) has posed a particular challenge for rapid response systems (RRSs) due to increased hospital strain and direct risk of infection to RRS team members. OBJECTIVE: We sought to characterize RRS structure and protocols adaptions during the COVID-19 pandemic. DESIGN SETTING AND PARTICIPANTS: Internet-based cross-sectional survey of RRS leaders, physicians, and researchers across the United States. RESULTS: Clinicians from 46 hospitals were surveyed, 40 completed a baseline survey (87%), and 19 also completed a follow-up qualitative survey. Most reported an increase in emergency team resources during the COVID-19 pandemic. The number of sites performing simulation training sessions decreased from 88% before COVID-19 to 53% during the pandemic. CONCLUSIONS: Most RRSs reported pandemic-related adjustments, most commonly through increasing resources and implementation of protocol changes. There was a reduction in the number of sites that performed simulation training.

Focused Transesophageal Echocardiography During Cardiac Arrest Resuscitation: JACC Review Topic of the Week.

Focused transthoracic echocardiography (TTE) during cardiac arrest resuscitation can enable the characterization of myocardial activity, identify potentially treatable pathologies, assist with rhythm interpretation, and provide prognostic information. However, an important limitation of TTE is the difficulty obtaining interpretable images due to external and patient-related limiting factors. Over the last decade, focused transesophageal echocardiography (TEE) has been proposed as a tool that is ideally suited to image patients in extremis-those in cardiac arrest and periarrest states. In addition to the same diagnostic and prognostic role provided by TTE images, TEE provides unique advantages including the potential to optimize the quality of chest compressions, shorten cardiopulmonary resuscitation interruptions, guide resuscitative procedures, and provides a continuous image of myocardial activity. This review discusses the rationale, supporting evidence, opportunities, and challenges, and proposes a research agenda for the use of focused TEE in cardiac arrest with the goal to improve resuscitation outcomes.

Critical Care Transesophageal Echocardiography in Patients during the COVID-19 Pandemic.

BACKGROUND: The COVID-19 pandemic has placed an extraordinary strain on healthcare systems across North America. Defining the optimal approach for managing a critically ill COVID-19 patient is rapidly changing. Goal-directed transesophageal echocardiography (TEE) is frequently used by physicians caring for intubated critically ill patients as a reliable imaging modality that is well suited to answer questions at bedside. METHODS: A multidisciplinary (intensive care, critical care cardiology, and emergency medicine) group of experts in point-of-care echocardiography and TEE from the United States and Canada convened to review the available evidence, share experiences, and produce a consensus statement aiming to provide clinicians with a framework to maximize the safety of patients and healthcare providers when considering focused point-of-care TEE in critically ill patients during the COVID-19 pandemic. RESULTS: Although transthoracic echocardiography can provide the information needed in most patients, there are specific scenarios in which TEE represents the modality of choice. TEE provides acute care clinicians with a goal-directed framework to guide clinical care and represents an ideal modality to evaluate hemodynamic instability during prone ventilation, perform serial evaluations of the lungs, support cardiac arrest resuscitation, and guide veno-venous ECMO cannulation. To aid other clinicians in performing TEE during the COVID-19 pandemic, we describe a set of principles and practical aspects for performing examinations with a focus on the logistics, personnel, and equipment required before, during, and after an examination. CONCLUSIONS: In the right clinical scenario, TEE is a tool that can provide the information needed to deliver the best and safest possible care for the critically ill patients.

Transesophageal Echocardiography at the Golden Hour: Identification of Blunt Traumatic Aortic Injuries in the Emergency Department.

BACKGROUND: Although surface sonography has become an essential diagnostic tool in the evaluation of trauma patients, important limitations of this modality include the evaluation of retroperitoneal hemorrhage and mediastinal pathology, such as blunt traumatic aortic injuries (BTAI). As in other emergency applications where surface sonography can't provide the information needed, focused transesophageal echocardiography (TEE) may represent a valuable diagnostic tool in the evaluation of hemodynamically unstable trauma patients with suspected thoracic pathology such as BTAI. CASE SERIES: We present a series of five cases that illustrate the diagnostic value of emergency physician-performed resuscitative TEE in the diagnosis of BTAI in patients presenting with blunt thoracic trauma. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: As the use of point-of-care TEE during resuscitation continues to expand in emergency medicine, the evaluation of patients with BTAI represents a novel application where this emerging modality can allow early diagnosis of these injuries in hemodynamically unstable patients.