Venous congestion in septic shock quantified with point-of-care ultrasound: a pilot prospective multicentre cohort study.

PURPOSE: Venous congestion is a pathophysiologic state that can result in organ dysfunction, particularly acute kidney injury (AKI). We sought to evaluate the feasibility of performing a definitive observational study to determine the impact of venous congestion quantified using point-of-care ultrasound (POCUS) in patients with septic shock. METHODS: We conducted a prospective observational feasibility study at two intensive care units (ICUs). We recruited adult patients with septic shock within 12 hr of ICU admission. Using the validated Venous Excess Ultrasound Score (VEXUS), we quantified venous congestion on day 1 and day 3 of ICU admission. The primary feasibility outcome was successful completion rate of the two VEXUS scores. We performed a survival analysis to quantify the hazard of renal replacement therapy (RRT). RESULTS: We enrolled 75 patients from January 2022 to January 2023. The success rate of completion for VEXUS scans was 94.5% (95% confidence interval [CI], 89.5 to 97.6). Severe venous congestion was present in 19% (14/75) of patients on ICU admission day 1 and in 16% (10/61) of patients on day 3. Venous congestion on ICU admission may be associated with a higher risk of requiring RRT (unadjusted hazard ratio, 3.35; 95% CI, 0.94 to 11.88; P = 0.06). CONCLUSIONS: It is feasible to conduct a definitive observational study exploring the association between venous congestion quantified with POCUS and clinical outcomes in patients with septic shock. We hypothesize that venous congestion may be associated with an increased hazard of receiving RRT.

RéSUMé: OBJECTIF: La congestion veineuse est un état physiopathologique qui peut entraîner un dysfonctionnement des organes, en particulier une insuffisance rénale aiguë (IRA). Nous avons cherché à évaluer la faisabilité de la réalisation d'une étude observationnelle définitive pour déterminer l'impact de la congestion veineuse quantifiée à l'aide de l'échographie ciblée (POCUS) chez des patient·es en choc septique. MéTHODE: Nous avons réalisé une étude de faisabilité observationnelle prospective dans deux unités de soins intensifs (USI). Nous avons recruté des patient·es adultes souffrant d'un choc septique dans les 12 heures suivant leur admission aux soins intensifs. À l'aide du score VEXUS (score d'échographie de l'excès veineux) validé, nous avons quantifié la congestion veineuse au jour 1 et au jour 3 de leur admission aux soins intensifs. Le principal critère de faisabilité était le taux de réussite des deux scores VEXUS. Nous avons réalisé une analyse de survie pour quantifier le risque de thérapie de substitution rénale (TSR). RéSULTATS: Nous avons recruté 75 patient·es de janvier 2022 à janvier 2023. Le taux de réussite des scores VEXUS était de 94,5 % (intervalle de confiance [IC] à 95 %, 89,5 à 97,6). Une congestion veineuse sévère était présente chez 19 % (14/75) des patient·es au jour 1 d'admission aux soins intensifs et chez 16 % (10/61) des patient·es au jour 3. La congestion veineuse lors de l'admission aux soins intensifs peut être associée à un risque plus élevé de nécessiter une TSR (rapport de risque non ajusté, 3,35; IC 95 %, 0,94 à 11,88; P = 0,06). CONCLUSION: Il est possible de mener une étude observationnelle définitive explorant l'association entre la congestion veineuse quantifiée par POCUS et les devenirs cliniques chez les patient·es en choc septique. Nous émettons l'hypothèse que la congestion veineuse peut être associée à un risque accru de recevoir une thérapie de substitution rénale.

Prospective Real-Time Validation of a Lung Ultrasound Deep Learning Model in the ICU.

OBJECTIVES: To evaluate the accuracy of a bedside, real-time deployment of a deep learning (DL) model capable of distinguishing between normal (A line pattern) and abnormal (B line pattern) lung parenchyma on lung ultrasound (LUS) in critically ill patients. DESIGN: Prospective, observational study evaluating the performance of a previously trained LUS DL model. Enrolled patients received a LUS examination with simultaneous DL model predictions using a portable device. Clip-level model predictions were analyzed and compared with blinded expert review for A versus B line pattern. Four prediction thresholding approaches were applied to maximize model sensitivity and specificity at bedside. SETTING: Academic ICU. PATIENTS: One-hundred critically ill patients admitted to ICU, receiving oxygen therapy, and eligible for respiratory imaging were included. Patients who were unstable or could not undergo an LUS examination were excluded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 100 unique ICU patients (400 clips) were enrolled from two tertiary-care sites. Fifty-six patients were mechanically ventilated. When compared with gold standard expert annotation, the real-time inference yielded an accuracy of 95%, sensitivity of 93%, and specificity of 96% for identification of the B line pattern. Varying prediction thresholds showed that real-time modification of sensitivity and specificity according to clinical priorities is possible. CONCLUSIONS: A previously validated DL classification model performs equally well in real-time at the bedside when platformed on a portable device. As the first study to test the feasibility and performance of a DL classification model for LUS in a dedicated ICU environment, our results justify further inquiry into the impact of employing real-time automation of medical imaging into the care of the critically ill.

Indications, Clinical Impact, and Complications of Critical Care Transesophageal Echocardiography: A Scoping Review.

BACKGROUND: Critical care transesophageal echocardiography (ccTEE) is an increasingly popular tool used by intensivists to characterize and manage hemodynamics at the bedside. Its usage appears to be driven by expanded diagnostic scope as well as the limitations of transthoracic echocardiography (TTE) - lack of acoustic windows, patient positioning, and competing clinical interests (eg, the need to perform chest compressions). The objectives of this scoping review were to determine the indications, clinical impact, and complications of ccTEE. METHODS: MEDLINE, EMBASE, Cochrane, and six major conferences were searched without a time or language restriction on March 31st, 2021. Studies were included if they assessed TEE performed for adult critically ill patients by intensivists, emergency physicians, or anesthesiologists. Intraoperative or post-cardiac surgical TEE studies were excluded. Study demographics, indication for TEE, main results, and complications were extracted in duplicate. RESULTS: Of the 4403 abstracts screened, 289 studies underwent full-text review, with 108 studies (6739 patients) included. Most studies were retrospective (66%), performed in academic centers (84%), in the intensive care unit (73%), and were observational (55%). The most common indications for ccTEE were hemodynamic instability, trauma, cardiac arrest, respiratory failure, and procedural guidance. Across multiple indications, ccTEE was reported to change the diagnosis in 52% to 78% of patients and change management in 32% to79% patients. During cardiac arrest, ccTEE identified the cause of arrest in 25% to 35% of cases. Complications of ccTEE included two cases of significant gastrointestinal bleeding requiring intervention, but no other major complications (death or esophageal perforation) reported. CONCLUSIONS: The use of ccTEE has been described for the diagnosis and management of a broad range of clinical problems. Overall, ccTEE was commonly reported to offer additional diagnostic yield beyond TTE with a low observed complication rate. Additional high quality ccTEE studies will permit stronger conclusions and a more precise understanding of the trends observed in this scoping review.

Ten Influential Point-of-Care Ultrasound Papers: 2022 in Review.

Keeping up with the latest developments in the point-of-care ultrasound (POCUS) literature is challenging, as with any area of medicine. Our group of POCUS experts has selected 10 influential papers from the past 12 months and provided a short summary of each. We hope to provide emergency physicians, intensivists, and other acute care providers with a succinct update concerning some key areas of ultrasound interest.

Acquisition and retention of lung ultrasound skills by respiratory therapists: A curriculum for respiratory therapists.

Purpose: Lung point-of-care ultrasound (POCUS) is a versatile bedside tool. The utility of POCUS has grown during the coronavirus disease 2019 pandemic, as it allows clinicians to obtain real-time images without requiring transport of the patient outside the intensive care unit. As respiratory therapists (RTs) are involved in caring for those with respiratory failure, there is a good rationale for their adoption of lung ultrasound. However, no training standards have been defined. Our objective was to develop and implement a training programme for RTs to achieve and sustain competence in lung ultrasound. Methods: This was a single-centre, prospective, single-cohort observational study. A total of 10 RTs completed our curriculum and were tasked with independently completing and interpreting 10 initial lung ultrasound exams and 3 subsequent exams after a 6-week interim period. All exams were blindly overread by a local expert in lung ultrasound. Results: After completing the curriculum, RTs were able to acquire and accurately interpret their images over 85% of the time. They were more successful in the upper lung zone image acquisition and interpretation compared with the lower lung zones. After 6 weeks, the RTs' lung POCUS skills remained stable, and their lower lung zone image interpretation improved. The RTs reported that their confidence improved throughout the study. Conclusion: The RTs in our study have demonstrated competence in acquisition and interpretation of upper lung zone images. They have also reported confidence in acquiring and interpreting upper lung zone images. More experience appears to be required to gain competence and confidence in lower lung zone ultrasound. Next steps would be to repeat the present study with a higher number of RTs completing at least 20 lung POCUS studies.

Ten Influential Point-of-Care Ultrasound Papers: 2021 in Review.

The ongoing rapid expansion of point-of-care ultrasound (POCUS) and its corresponding supporting literature leaves the frontline clinician in a difficult position when trying to keep abreast of the latest developments. Our group of POCUS experts has selected ten influential POCUS-related papers from the past twelve months and provided a short summary of each. Our aim is to give to emergency physicians, intensivists, and other acute care providers key information, helping them to keep up to date on rapidly evolving POCUS literature.

Assessing Competence in Critical Care Echocardiography: Development and Initial Results of an Examination and Certification Processes.

OBJECTIVES: To describe the development and initial results of an examination and certification process assessing competence in critical care echocardiography. DESIGN: A test writing committee of content experts from eight professional societies invested in critical care echocardiography was convened, with the Executive Director representing the National Board of Echocardiography. Using an examination content outline, the writing committee was assigned topics relevant to their areas of expertise. The examination items underwent extensive review, editing, and discussion in several face-to-face meetings supervised by National Board of Medical Examiners editors and psychometricians. A separate certification committee was tasked with establishing criteria required to achieve National Board of Echocardiography certification in critical care echocardiography through detailed review of required supporting material submitted by candidates seeking to fulfill these criteria. SETTING: The writing committee met twice a year in person at the National Board of Medical Examiner office in Philadelphia, PA. SUBJECTS: Physicians enrolled in the examination of Special Competence in Critical Care Electrocardiography (CCEeXAM). MEASUREMENTS AND MAIN RESULTS: A total of 524 physicians sat for the examination, and 426 (81.3%) achieved a passing score. Of the examinees, 41% were anesthesiology trained, 33.2% had pulmonary/critical care background, and the majority had graduated training within the 10 years (91.6%). Most candidates work full-time at an academic hospital (46.9%). CONCLUSIONS: The CCEeXAM is designed to assess a knowledge base that is shared with echocardiologists in addition to that which is unique to critical care. The National Board of Echocardiography certification establishes that the physician has achieved the ability to independently perform and interpret critical care echocardiography at a standard recognized by critical care professional societies encompassing a wide spectrum of backgrounds. The interest shown and the success achieved on the CCEeXAM by practitioners of critical care echocardiography support the standards set by the National Board of Echocardiography for testamur status and certification in this imaging specialty area.

Training strategies for point of care ultrasound in the ICU.

PURPOSE OF REVIEW: Ultrasound in critical care medicine (CCUS) is a relatively young tool that has been evolving rapidly as skillsets, applications and technology continue to progress. Although ultrasound is identified as a core competency in intensive care unit (ICU) training, there remains significant variability and inconsistencies in the delivery of ultrasound training. The goal of this narrative review is to explore areas of consensus and highlight areas where consensus is lacking to bring attention to future directions of ultrasound training in critical care medicine. RECENT FINDINGS: There exists considerable variation in competencies identified as basic for CCUS. Recent efforts by the European Society of Intensive Care Medicine serve as the most up to date iteration however implementation is still limited by regional expertise and practice patterns. Major barriers to ultrasound training in the ICU include a lack of available experts for bedside teaching and a lack of familiarity with new technology. SUMMARY: Though international uptake of CCUS has made many gains in the past 20 years, further adoption of technology will be required to overcome the traditional barriers of CCUS training. Although the availability and time constraints of experts will remain a limitation even with wireless capabilities, the ability to expand beyond the physical constraints of an ultrasound machine will vastly benefit efforts to standardize training and improve access to knowledge.

Recommendations for core critical care ultrasound competencies as a part of specialist training in multidisciplinary intensive care: a framework proposed by the European Society of Intensive Care Medicine (ESICM).

Critical care ultrasound (CCUS) is an essential component of intensive care practice. Although existing international guidelines have focused on training principles and determining competency in CCUS, few countries have managed to operationalize this guidance into an accessible, well-structured programme for clinicians training in multidisciplinary intensive care. We seek to update and reaffirm appropriate CCUS scope so that it may be integrated into the international Competency-based Training in Intensive Care Medicine. The resulting recommendations offer the most contemporary and evolved set of core CCUS competencies for an intensive care clinician yet described. Importantly, we discuss the rationale for inclusion but also exclusion of competencies listed. BACKGROUND/AIM: Critical care ultrasound (CCUS) is an essential component of intensive care practice. The purpose of this consensus document is to determine those CCUS competencies that should be a mandatory part of training in multidisciplinary intensive care. METHODS: A three-round Delphi method followed by face-to-face meeting among 32 CCUS experts nominated by the European Society of Intensive Care Medicine. Agreement of at least 90% of experts was needed in order to enlist a competency as mandatory. RESULTS: The final list of competencies includes 15 echocardiographic, 5 thoracic, 4 abdominal, deep vein thrombosis diagnosis and central venous access aid. CONCLUSION: The resulting recommendations offer the most contemporary and evolved set of core CCUS competencies for an intensive care clinician yet described.

Impact of Critical Care Transesophageal Echocardiography in Medical-Surgical ICU Patients: Characteristics and Results From 274 Consecutive Examinations.

OBJECTIVE: Critical care echocardiography has become an integral tool in the assessment and management of critically ill patients. Critical care transesophageal echocardiography (TEE) offers diagnostic reliability, superior image quality, and an expanded diagnostic scope to transthoracic echocardiography. Despite its favorable attributes, TEE use in North American intensive care units (ICUs) remains relatively undescribed. In this article, we seek to characterize the feasibility, indications, and clinical impact of a critical care TEE program. DESIGN: Retrospective, observational study. SETTING: Tertiary care, academic critical care program consisting of 2 hospitals in Ontario, Canada. PARTICIPANTS: Consecutive critical care TEE examinations on ICU patients performed between December 2012 and December 2016. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Consecutive critical care TEE studies on ICU patients from December 1, 2012, to December 31, 2016, were reviewed. The TEEs performed on cardiac surgery patients and those without reports were excluded. Examination details, including indications, complications, examination complexity (number of views, Doppler techniques), and clinical recommendations were aggregated and analyzed. Two hundred seventy-four TEE studies were performed by 38 operators. Common indications for TEE studies were hemodynamic instability (45.2%), assessment for infective endocarditis (22.2%), and cardiac arrest (20.1%). A change in patient management was proposed following 79.5% of TEE studies. Thirty-eight percent of TEE studies were performed during evening hours or on weekends. There were no mechanical complications. CONCLUSIONS: Our observational data support intensivist-performed TEE as being safe and therapeutically influential across a broad range of indications. Our program's demonstrated feasibility and impact may act as a model for TEE adoption in other North American ICUs.

Creation and Testing of a Deep Learning Algorithm to Automatically Identify and Label Vessels, Nerves, Tendons, and Bones on Cross-sectional Point-of-Care Ultrasound Scans for Peripheral Intravenous Catheter Placement by Novices.

OBJECTIVES: We sought to create a deep learning (DL) algorithm to identify vessels, bones, nerves, and tendons on transverse upper extremity (UE) ultrasound (US) images to enable providers new to US-guided peripheral vascular access to identify anatomy. METHODS: We used publicly available DL architecture (YOLOv3) and deidentified transverse US videos of the UE for algorithm development. Vessels, bones, tendons, and nerves were labeled with bounding boxes. A total of 203,966 images were generated from videos, with corresponding label box coordinates in a YOLOv3 format. Training accuracy, losses, and learning curves were tracked. As a final real-world test, 50 randomly selected images from unrelated UE US videos were used to test the DL algorithm. Four different versions of the YOLOv3 algorithm were tested with varied amounts of training and sensitivity settings. The same 50 images were labeled by 2 blinded point-of-care ultrasound (POCUS) experts. The area under the curve (AUC) was calculated for the DL algorithm and POCUS expert performance. RESULTS: The algorithm outperformed POCUS experts in detection of all structures in the UE, with an AUC of 0.78 versus 0.69 and 0.71, respectively. When considering vessels, only one of the POCUS experts attained an AUC of 0.85, just ahead of the DL algorithm, with an AUC of 0.83. CONCLUSIONS: Our DL algorithm proved accurate at identifying 4 common structures on cross-sectional US imaging of the UE, which would allow novice POCUS providers to more confidently and accurately target vessels for cannulation, avoiding other structures. Overall, the algorithm outperformed 2 blinded POCUS experts.

Transesophageal Echocardiography: Guidelines for Point-of-Care Applications in Cardiac Arrest Resuscitation.

Cardiac arrest is one of the most challenging patient presentations managed by emergency care providers, and echocardiography can be instrumental in the diagnosis, prognosis, and treatment guidance in these critically ill patients. Transesophageal echocardiography has many advantages over transthoracic echocardiography in a cardiac arrest resuscitation. As transesophageal echocardiography is implemented more widely at the point of care during cardiac arrest resuscitations, guidelines are needed to assist emergency providers in acquiring the equipment and skills necessary to successfully incorporate it into the management of cardiac arrest victims.

Focused assessment with sonography in trauma: a review of concepts and considerations for anesthesiology.

The use of point-of-care ultrasound in trauma provides diagnostic clarity and routinely influences management. A scanning protocol known as the Focused Assessment with Sonography in Trauma (FAST) has been widely adopted by trauma providers of all specialties. The FAST exam addresses a broad array of pathologic conditions capable of causing instability, including hemoperitoneum, hemopericardium, hemothorax, and pneumothorax. The exam is an integral component to the primary assessment of injured patients and an iconic application of point-of-care ultrasound.This review article aims to summarize the application of the FAST exam with special consideration, where relevant, to anesthesiologists. The scope of the FAST exam, technical considerations, and clinical decision-making in trauma are explored.

Expert Agreement in the Interpretation of Lung Ultrasound Studies Performed on Mechanically Ventilated Patients.

OBJECTIVES: Although lung ultrasound (US) has been shown to have high diagnostic accuracy in patients presenting with acute dyspnea, its precision in critically ill patients is unknown. We investigated common areas of agreement and disagreement by studying 6 experts as they interpreted lung US studies in a cohort of intensive care unit (ICU) patients. METHODS: A previous study by our group asked experts to rate the quality of 150 lung US studies performed by 10 novices in a population of mechanically ventilated patients. For this study, experts were asked to interpret them without the clinical context, reporting the presence of pneumothorax, interstitial syndrome, consolidation, atelectasis, or pleural effusion. RESULTS: The rate of expert agreement depended on how it was defined, ranging from 51% (with a strict definition of agreement) to 57% (with a more liberal definition). Removing cases involving lung consolidation (the most common source of disagreement) improved the rates of agreement to 69% and 86%, respectively. CONCLUSIONS: The frequency of agreement was lower than might have been expected in this study. Several potential reasons are identified, chief among them the fact that ICU patients often develop multiple pulmonary insults, making agreement on a specific primary diagnosis challenging. This finding suggests that the utility of lung US in identifying the main contributing lung condition in ICU patients may be lower than in dyspneic patients encountered in the emergency department. It also raises the possibility that the clinical context is more important for lung US than other imaging modalities.

The Rapid Assessment of Competency in Echocardiography Scale: Validation of a Tool for Point-of-Care Ultrasound.

OBJECTIVES: Increased use of point-of-care ultrasound (US) requires the development of assessment tools that measure the competency of learners. In this study, we developed and tested a tool to assess the quality of point-of-care cardiac US studies performed by novices. METHODS: In phase 1, the Rapid Assessment of Competency in Echocardiography (RACE) scale was developed on the basis of structured interviews with subject matter experts; the tool was then piloted on a small series of US studies in phase 2. In phase 3, the tool was applied to a sample of 154 point-of-care US studies performed by 12 learners; each study was independently rated by 2 experts, with quantitative analysis subsequently performed. RESULTS: Evidence of the content validity of the RACE scale was supported by a consensus exercise, wherein experts agreed on the assessment dimensions and specific items that made up the RACE scale. The tool showed good inter-rater reliability. An analysis of inter-item correlations provided support for the internal structure of the scale, and the tool was able to discriminate between learners early in their point-of-care US learning and those who were more advanced in their training. CONCLUSIONS: The RACE scale provides a straightforward means to assess learner performance with minimal requirements for evaluator training. Our results support the conclusion that the tool is an effective means of making valid judgments regarding competency in point-of-care cardiac US.

Focused Transesophageal Echocardiography by Emergency Physicians is Feasible and Clinically Influential: Observational Results from a Novel Ultrasound Program.

BACKGROUND: Emergency physicians frequently employ transthoracic echocardiography (TTE) to assist in diagnosis and therapy for patients with circulatory failure or arrest. In critically ill patients, transesophageal echocardiography (TEE) offers several advantages over TTE, including reliable, continuous image acquisition and superior image quality. Despite these advantages, TEE is not widely used by emergency physicians. OBJECTIVE: Report the feasibility, findings, and clinical influence observed from the first described TEE program implemented in an emergency department (ED) point-of-care ultrasound program. METHODS: This was a retrospective review of all ED TEE examinations carried out between February 1, 2013 and January 30, 2015. TEE images and report details (including operator, indication, findings, and clinical recommendation[s]) were exported from the institutional ultrasound archive and analyzed. The electronic chart of each patient was subsequently reviewed for the presence of any complications related to the examination and their clinical course in the hospital. RESULTS: A total of 54 TEE examinations were performed by 12 different emergency physicians. All patients were intubated, and 98% of the examinations were determinate. The most common indications for TEE were intracardiac arrest care in 23 (43%), postarrest management in 14 (26%), and undifferentiated hypotension in 16 (40%). Probe insertion was successful in all cases. TEE imparted a diagnostic influence in 78% of cases and impacted therapeutic decisions in 67% of cases. CONCLUSION: From our analysis of a single-center experience, ED-based TEE showed a high degree of feasibility and clinical utility, with a diagnostic and therapeutic influence seen in the majority of cases. Focused TEE demonstrated strongest uptake among intubated patients with either undifferentiated shock or cardiac arrest.