A Freehand 3D Ultrasound Carotid Scanning System for Point-of-Care Ultrasonography

Stroke is a leading cause of morbidity and mortality throughout the world. Three-dimensional ultrasound (3DUS) imaging was shown to be more sensitive to treatment effect and more accurate in stratifying stroke risk than two-dimensional ultrasound (2DUS) imaging. Point-of-care ultrasound screening (POCUS) is important for patients with limited mobility and at times when the patients have limited access to the ultrasound scanning room, such as in the COVID-19 era. We used an optical tracking system to track the 3D position and orientation of the 2DUS frames acquired by a commercial wireless ultrasound system and subsequently reconstructed a 3DUS image from these frames. The tracking requires spatial and temporal calibrations. Spatial calibration is required to determine the spatial relationship between the 2DUS machine and the tracking system. Spatial calibration was achieved by localizing the landmarks with known coordinates in a custom-designed Z-fiducial phantom in an 2DUS image. Temporal calibration is needed to synchronize the clock of the wireless ultrasound system and the optical tracking system so that position and orientation detected by the optical tracking system can be registered to the corresponding 2DUS frame. Temporal calibration was achieved by initiating the scanning by an abrupt motion that can be readily detected in both systems. This abrupt motion establishes a common reference time point, thereby synchronizing the clock in both systems. We demonstrated that the system can be used to visualize the three-dimensional structure of a carotid phantom. The error rate of the measurements is 2.3%. Upon in-vivo validation, this system will allow POCUS carotid scanning in clinical research and practices. © 2023 SPIE.

Determinants of point-of-care ultrasound lung sliding amplitude in mechanically ventilated patients.

BACKGROUND: Although lung sliding seen by point-of-care ultrasound (POCUS) is known to be affected to varying degrees by different physiologic and pathologic processes, it is typically only reported qualitatively in the critical care setting. Lung sliding amplitude quantitatively expresses the amount of pleural movement seen by POCUS but its determinants in mechanically ventilated patients are largely unknown. METHODS: This was a single-center, prospective, observational pilot study examining 40 hemithoraces in 20 adult patients receiving mechanical ventilation. Each subject had lung sliding amplitude measured in both B-mode and by pulsed wave Doppler at their bilateral lung apices and bases. Differences in lung sliding amplitude were correlated with anatomical location (apex vs base) as well as physiologic parameters including positive end expiratory pressure (PEEP), driving pressure, tidal volume and the ratio of arterial partial pressure of oxygen (PaO2) to fraction of inspired oxygen (FiO2). RESULTS: POCUS lung sliding amplitude was significantly lower at the lung apex compared to the lung base in both B-mode (3.6 ± 2.0 mm vs 8.6 ± 4.3 mm; p < 0.001) and the pulsed wave Doppler mode (10.3 ± 4.6 cm/s vs 13.9 ± 5.5 cm/s; p < 0.001) corresponding to expected distribution of ventilation to the lung bases. Inter-rater reliability of B-mode measurements was excellent (ICC = 0.91) and distance traversed in B-mode had a significant positive correlation with pleural line velocity (r2 = 0.32; p < 0.001). There was a non-statistically significant trend towards lower lung sliding amplitude for PEEP ≥ 10 cmH2O, as well as for driving pressure ≥ 15 cmH2O in both ultrasound modes. CONCLUSION: POCUS lung sliding amplitude was significantly lower at the lung apex than the lung base in mechanically ventilated patients. This was true when using both B-mode and pulsed wave Doppler. Lung sliding amplitude did not correlate with PEEP, driving pressure, tidal volume or PaO2:FiO2 ratio. Our findings suggest that lung sliding amplitude can be quantified in mechanically ventilated patients in a physiologically predictable way and with high inter-rater reliability. A better understanding of POCUS derived lung sliding amplitude and its determinants may aid in the more accurate diagnosis of lung pathologies, including pneumothorax, and could serve as a means of further reducing radiation exposure and improving outcomes in critically ill patients.

Lessons Learned from POCUS Instruction in Undergraduate Medicine During the COVID-19 Pandemic.

Point of care Ultrasound (POCUS) has been adopted into clinical practice across many fields of medicine. Undergraduate medical education programs have recognized the need to incorporate POCUS training into their curricula, traditionally done in small groups with in-person sessions. This method is resource intensive and requires sufficient equipment and expertise. These requirements are often cited as barriers for implementation. During the Coronavirus Disease 2019 (COVID-19) pandemic, POCUS education was required to adapt to physical distancing regulations, giving rise to novel teaching methods for POCUS. This article outlines the implementation of a POCUS teaching session before and during the pandemic. It describes how these innovations can scale POCUS teaching and overcome barriers moving forward. A flipped classroom model was implemented for all learners. Learners were given an introductory POCUS module before the scheduled in-person or virtual teaching session. Sixty-nine learners participated in conventional in-person teaching, while twenty-two learners participated in virtual teaching following the pandemic-related restrictions. Learners completed a written test before and following the teaching. In-person learners were assessed using an objective structured assessment of ultrasound skills (OSAUS) pre- and post-learning sessions. A follow-up survey was conducted three years after the teaching sessions were completed. Both in-person and virtual groups demonstrated statistically significant improvement in knowledge scores (p <0.0001). Both groups had similar post-test learning scores (74.2 ± 13.6% vs. 71.8 ± 14.5 %, respectively). On follow-up questionnaires, respondents indicate that they found our online and in-person modes of teaching helpful during their residency. POCUS education continues to face a variety of barriers, including limitations in infrastructure and expertise. This study describes an adapted POCUS teaching model that is scalable, uses minimal infrastructure and retains the interactivity of conventional small-group POCUS teaching. This program can serve as a blueprint for other institutions offering POCUS teaching, especially when conventional teaching methods are limited.

Multi-organ ultrasound for SARS-COV-2 disease

Aim: There is growing evidence regarding the imaging ultrasound findings of coronavirus disease 2019 COVID-19. Multi-organ ultrasound has played a significant role in the diagnosis and follow-up of these patients. The aim of this study was to describe the ultrasound findings at pulmonary, cardiac and deep venous system of the lower extremities in patients with SARS-COV-2 infection. Material and method: Prospective, cross-sectional, observational study was conducted in patients with confirmed COVID-19 who underwent a multi-organ point-of-care ultrasound (POCUS) examination during hospitalization. Results: A total of 107 patients were enrolled. Lung involvement was present in 100% of the patients, 93.4% bilaterally involvement. The most affected lung area was the posteroinferior (94.39%) followed by the lateral (89.72%). Subpleural consolidations were present in 71% of patients and consolidations larger than 1 cm in 25%. More echographic lung involvement is relational with the degree of respiratory insufficiency. Only two patients had proximal deep vein thrombosis in the lower extremities, 27 angiography tomography scan were performed and pulmonary thromboembolism was confirmed in 14 patients. The most frequent echocardiographic findings were impaired left ventricular relaxation and left ventricular hypertrophy. All patients with thromboembolic disease had severe or critical echocardiographic pulmonary involvement. Conclusions: Multi-organ POCUS ultrasound may be useful for the manifestations of COVID-19. The degree of lung ultrasound involvement was related to the degree of respiratory failure and to the presence of VTED. The relationship between DVT and PTE was lower than expected. Cardiac involvement has little relevance in our series.

A new non-invasive index for the prediction of endotracheal intubation in patients with SARS COVID-19 infection, in the emergency department, pilot study.

BACKGROUND: In the current context of the SARS COVID-19 pandemic, where the main cause of death is respiratory failure, and since early recognition would allow timely measures to be implemented and probably improve outcomes, it is important to have tools that allow the emergency room to predict quickly and without the use of large resources which will need invasive mechanical ventilation. This study proposes using a new predictive index of noninvasive characteristics, based on the relationship between oxygenation and work of breathing measured by ultrasound-assessed diaphragmatic function, for the need for invasive mechanical ventilation in patients with SARS-COV2 infection who are admitted to the emergency department. METHODS: A prospective predictive cohort study was performed, collecting all patients admitted to the emergency room with respiratory failure (not severe or in imminent respiratory arrest) and a confirmed diagnosis of SARS-CoV-2 pneumonia. Diaphragmatic excursion measurements were taken within the first 24 h after admission to the department. The relationship between diaphragmatic excursion and SAFI was calculated, establishing the ultrasound diaphragmatic excursion So2/FiO2 index (U.D.E.S.I). The index's performance was determined by analysis of sensitivity, specificity, and area under the curve (AUC). RESULTS: This pilot study analyzed the first 100 patients enrolled and found in-hospital mortality of 19%, all patients who died required mechanical ventilation, the right index showed a specificity of 82.4% with a sensitivity of 76.9%, likewise for the left index an overall specificity of 90.5% with a sensitivity of 65.3% was found. The ideal cut-off point for the right index is 1.485, and for the left index, the threshold point was 1.856. AUC of the right index is 0.798 (0.676-0.920) and of the left index 0.793 (0.674-0.911), when comparing them no significant differences were found between these values p = 0.871. CONCLUSION: The relationship of So2/FiO2 and diaphragm excursion measured by both right and left ultrasound could predict the need for mechanical ventilation of the patient with COVID-19 pneumonia in the emergency room and could constitute a valuable tool since it uses noninvasive parameters and is easily applicable at the patient's bedside. However, a more extensive study is needed to validate these preliminary results.

Point-of-Care Ultrasound Can Suggest COVID-19.

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the World Health Organization (WHO) declared it a pandemic on 11 March 2020. Point-of-care ultrasound (POCUS) is a real-time bedside tool used by physicians to guide rapid, focused and accurate evaluation in order to identify or rule out various pathologies. We describe the case of an elderly man who had fallen at home 3 days previously and was hypoxic at presentation to the emergency department (ED). POCUS in the ED helped to identify a combination of lung and vascular involvement that indicated COVID-19 infection, which was confirmed by a laboratory test. LEARNING POINTS: COVID-19 is a contagious disease caused by SARS-CoV-2 that attacks endothelial cells and most organs, resulting in different manifestations and clinical scenarios.Point-of-care ultrasound in the emergency room including lung ultrasound (LUS) and focused echocardiography (FECHO) can be useful in identifying pulmonary and vascular manifestations of COVID-19 disease during the current pandemic.Characteristic LUS signs suggesting bilateral interstitial pneumonia in addition to signs of acute right ventricular strain suggesting pulmonary embolism on FECHO raised the suspicion of COVID-19 infection in our patient.

Role of Point of Care Ultrasonography in Patients with COVID-19 Associated Acute Kidney Injury.

The severe acute respiratory virus covariate-2 (SARS CoV-2) that causes Corona Virus Disease 2019 (COVID-19) has affected more than 194 million people worldwide and has attributed to or caused more than 4 million deaths. Acute kidney injury (AKI) is a common complication of COVID-19. Point of care ultrasonography (POCUS) can be a useful tool for the nephrologist. POCUS can be used to elucidate the cause of kidney disease and then also help to manage volume status. Here, we review pearls and pitfalls of using POCUS to manage COVID-19 associated AKI with special attention to kidney, lung, and cardiac ultrasound.

Can the Use of Bedside Lung Ultrasound Reduce Transmission Rates in The Case of The COVID-19 Patient? - A Narrative Review.

Novel Corona Virus Disease-19 (nCov-19, COVID-19) was recognised as a pandemic by the World Health Organization on March 11, 2020. As of June 14, 2020, this contagious viral disease has afflicted 188 out of 195 countries in the world with 7,893,700 confirmed cases and 432,922 global deaths.Canada has 98,787 people infected and 8,146 deaths. COVID-19 is thought to transmit through contact, droplets and aerosolization. A rapid review showed limited information on the benefits of conducting lung ultrasound (LUS) versus chest radiograph (CXR) or studies correlating lung ultrasound to chest computed Tomography (CT) in patients positive for Covid-19. The literature review confirmed that CT and LUS cannot diagnose this disease, but that both can help in the management and staging of this disease. There is no literature to prove that LUS at the bedside may be beneficial from the view of decreased transmission to other health care workers and bystanders due to reduced transit but comparing the transit pathway and contact leads one to propose that this would be so. Pregnant patients with COVID-19, young children and patients in the reproductive stage would also benefit from LUS since there is no radiation dose and the critical patient in distress will benefit from testing at the bedside.

Screening for asymptomatic deep vein thrombosis in COVID-19 patients admitted to the medical ward: a cross-sectional study.

PURPOSE: Patients with COVID-19 have an increased risk for venous thrombo-embolism (VTE), especially pulmonary embolism. The exact prevalence of asymptomatic DVT is not known, as is the usefulness of screening for DVT in patients admitted to ward with COVID-19. We have studied the prevalence of asymptomatic DVT. METHODS: We performed a cross-sectional observational multi-center study at four university medical centers in The Netherlands. All adult patients admitted with COVID-19 to a medical ward were eligible for inclusion, including patients who were transferred back from the ICU to the ward. The study protocol consisted of weekly cross-sectional rounds of compression ultrasound. RESULTS: In total, 125 patients were included in the study. A significant proportion of patients (N = 34 (27%)) had developed a VTE during their admission for COVID-19 before the study ultrasound was performed. In most VTE cases (N = 27 (79%)) this concerned pulmonary embolism. A new asymptomatic DVT was found in 5 of 125 patients (4.0%; 95% CI 1.3-9.1%) (Table 2). Nine patients (7.2%; 95% CI 3.3-13.2%) developed a VTE (all PE) diagnosed within 28 days after the screening US was performed. CONCLUSION: We have shown a low prevalence (4%) of newly discovered asymptomatic DVT outside the ICU-setting in COVID-19 patients. Despite this low prevalence, nine patients developed PE (7%) within 28 days after ultrasound. This favors the hypothesis of local thrombus formation in the lungs. Based on our findings and literature, we do not recommend US-screening of asymptomatic patients with COVID-19 admitted to the ward.

Point-of-care ultrasound in the detection of central retinal artery occlusion in a patient with recent COVID-19.

Ocular emergencies are a frequent occurrence in the emergency setting. Fortunately, point-of-care ultrasound (POCUS) lends itself exceptionally well to ocular evaluation. Here, we present a unique case of central retinal artery occlusion rapidly diagnosed with POCUS in a patient with a recent COVID-19 diagnosis.

Three Zone Scanning Protocol For Lung Ultrasound: An Anatomical Basis.

Lung ultrasound is rapidly gaining popularity based on point of care ease of use, diagnostic fidelity and lack of ionizing radiation. This was particularly notable at the beginning of the COVID-19 pandemic, where concerns of contamination of the x-ray department led to a reluctance to order frequent chest x-rays. Early COVID-19 lung involvement is of a bronchopneumonia, and patches of consolidation adjacent to the chest wall were easily detectable by ultrasound. A large number of proposed scanning protocols were advocated and are often complex and largely based on traditional stethoscope examination or access points on the chest wall rather than the underlying lung anatomy. A surgical understanding of lung anatomy and related surface anatomy has led us to develop a simplified three zone scanning protocol in 2013. The anterior zone corresponds to the upper lobe, and the posterior zone is divided between upper lobe and lower lobe. The relationship between lung lobes and the surface of the chest wall provides the anatomical basis for a simple three scanning zone lung ultrasound protocol.

Lung ultrasonography performed by nephrologist: COVID-19 as an opportunity to reveal ultrasound's full potential and usefulness in the dialysis room.

Background: Interest in point-of-care ultrasound (POCUS) and lung ultrasound (LUS) is growing in the nephrology and dialysis field, and the number of nephrologists skilled in what is proving to be the "5th pillar of bedside physical examination" is increasing. Patients on hemodialysis (HD) are at high risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) and developing coronavirus disease 2019 (COVID-19) serious complications. Despite this, to our knowledge there are no studies to date that show the role of LUS in this setting, while there are many in the emergency room, where LUS proved to be an important tool, providing risk stratification and guiding management strategies and resource allocation. Therefore, it is not clear whether the usefulness and cut-offs of LUS highlighted in studies in the general population are reliable in dialysis, or whether variations, precautions and adjustments to this specific situation are necessary. Methods: This was a 1-year monocentric prospective observational cohort study of 56 HD patients with COVID-19. Patients underwent a monitoring protocol that included at first evaluation bedside LUS, using a 12-scan scoring system, by the same nephrologist. All data were prospectively and systematically collected. Outcomes. hospitalization rate, combined outcome [non-invasive ventilation (NIV + death)], mortality. Descriptive variables are presented as medians (interquartile range), or percentage. Univariate and multivariate analysis, as well as Kaplan-Meier (K-M) survival curves, were carried out. P was fixed at .05. Results: Median age was 78 years, 90% had at least one comorbidity (46% diabetics), 55% were hospitalized and 23% deaths. Median duration of disease was 23 days (14-34). A LUS score ≥11 represented a 13-fold risk of hospitalization, a 16.5-fold risk of combined outcome (NIV + death) vs risk factors such as age [odds ratio (OR) 1.6], diabetes (OR 1.2), male sex (OR 1.3) and obesity (OR 1.25), and a 7.7-fold risk of mortality. In the logistic regression, LUS score ≥11 is associated with the combined outcome with a hazard ratio (HR) of 6.1 vs inflammations indices such as CRP ≥9 mg/dL (HR 5.5) and interleukin-6 (IL-6) ≥62 pg/mL (HR 5.4). In K-M curves, survival drops significantly with LUS score above 11. Conclusions: In our experience of COVID-19 HD patients, LUS appeared to be an effective and easy tool, predicting the need for NIV and mortality better than "classic" known COVID-19 risk factors such as age, diabetes, male sex and obesity, and even better than inflammations indices such as CRP and IL-6. These results are consistent with those of the studies in the emergency room setting, but with a lower LUS score cut-off (11 vs 16-18). This is probably due to the higher global frailty and peculiarity of HD population, and emphasizes how nephrologists should themselves use LUS and POCUS as a part of their everyday clinical practice, adapting it to the peculiarity of the HD ward.

Three Cases of Right Heart Thrombus: Using POCUS for the Diagnosis of Thromboembolism in COVID-19.

COVID-19 generates a series of challenges, one of them being thrombotic manifestations of the disease. The growing use of POCUS and its wide versatility have expanded its use outside of radiology rooms. The development of focused protocols has facilitated its use in emergency units, clinical wards, intensive care units, and operating rooms. We report three cases of patients with SARS-CoV-2 infection in whom the use of POCUS allowed the identification of the presence of intracavitary thrombus with acute right ventricular dysfunction. These cases illustrate the importance of ultrasound focused on critically ill patients in guiding the diagnosis and treatment amid the pandemic situation.

Mission POCUS in Haiti.

Introduction: Point-of-care ultrasound (POCUS) has enhanced patient care and safety around the world. Clinicians can now use a small diagnostic ultrasound imaging device to answer some binary clinical questions and manage patients more effectively. Since the COVID-19 pandemic, there has been a significant adoption of POCUS by clinicians worldwide. Materials and Methods: A basic cardiac POCUS training was conducted in Haiti with focus on physics, instrumentation, and basic echocardiography. Results: The Mission POCUS team trained 15 Haitian physicians interested in better serving their patients with the implementation of POCUS cardiac in their patient assessment. Conclusion: POCUS skills will empower clinicians from around the world to make rapid and accurate diagnosis and help save lives by diagnosing life threatening conditions and manage patient appropriately. Our experience in Haiti showed that a short POCUS training course can help improve the knowledge of physicians.

Advanced diagnostic and therapeutic techniques for anaesthetists in thoracic trauma: an evidence-based review.

Anaesthetists play an important role in the evaluation and treatment of patients with signs of thoracic trauma. Anaesthesia involvement can provide valuable input using both advanced diagnostic and therapeutic interventions. Commonly performed interventions may be complicated in this setting including airway management, damage control resuscitation, and acute pain management. Anaesthetists must consider additional factors including airway injuries, vascular injuries, and coagulopathy when treating this population. This evidence-based review discusses traumatic thoracic injuries with a focus on new interventions and modern anaesthesia techniques. This review further serves to support the early involvement of anaesthetists in the emergency department and other areas where they can provide value to the trauma care pathway.

Effect of prone position on right ventricular dysfunction due to pulmonary embolism assessed by speckle tracking echocardiography.

Prone position has shown beneficial hemodynamic effects in patients with right ventricular dysfunction associated with acute respiratory distress syndrome decreasing the right ventricle afterload. We describe the case of a 57-year-old man with right ventricular dysfunction associated with pulmonary thromboembolism with severe hypoxemia that required mechanical ventilation in prone position. With this maneuver, we verified an improvement not only in his oxygenation, but also in his right ventricular function assessed with speckle tracking echocardiography. Our case shows the potential beneficial effect of the prone position maneuver in severely hypoxemic patients with right ventricular dysfunction associated with pulmonary thromboembolism.

Possible applications of lung ultrasound - a Covid-19 case.

Background: Lung ultrasound is an im-portant tool for distinguishing between causes and therapies of cardiorespiratory diseases in emergency departments (ED). Aim and method: Based on a case report, the importance of point-of-care ultrasound (POCUS) in the context of emergency di-agnostics and intensive care therapy will be illustrated. Case report: A 78-year-old male presented to the ED with dyspnea und weakness. A double mRNA-Covid vaccination was completed 3 months before. His medical history revealed multiple myeloma. Using POCUS, a severe Covid-19 pneumonia could be suspected, and at the same time other differential diagnoses were ruled out. PCR confirmed a SARS-CoV-2 infection. The patient was admitted to our intensive care unit with severe Covid-19 pneumonia fol-lowed by a complicated and ultimately le-thal course. Conclusion(s): In immunocompro-mised patients, there is still a high risk of a severe and complex course despite vaccina-tion. POCUS allows evaluation of probable Covid-19 pneumonia and rapid exclusion of possible differential diagnoses. Copyright © 2022 Dustri-Verlag Dr. K. Feistle.

Point-of-Care Echocardiographic Characteristics of COVID-19 Patients with Pulmonary Embolism.

INTRODUCTION: Thrombotic complications, such as pulmonary embolism, are common in COVID-19 patients. Point-of-care ultrasound is a highly recommended tool for orientation in critically ill patients with suspected or confirmed complications. METHODS: An observational study was conducted on 32 consecutive patients with confirmed pulmonary embolism and COVID-19 infection treated in the Intensive Care Unit of the University Hospital Medical Center "Bezanijska kosa", Belgrade, Serbia, between April 2021 and March 2022. Predictors of the need for oxygen support were determined, while point-of-care echocardiographic parameters and various anamnestic, laboratory, and clinically significant parameters were correlated with the Pulmonary Embolism Severity Index (PESI) score. RESULTS: More than two-thirds of patients in our study had PE symptoms present at hospital admission (68.8%). The majority of patients had segmental pulmonary embolism (48.4%), with high to very high PESI score values in 31.3% of patients. Pneumonia was present in 68.8% of the study population. The PESI score was negatively correlated with diastolic blood pressure and SaO2 at the time of PE diagnosis, LV ejection fraction, and PVAT. A positive correlation was found between the PESI score, maximum CRP, and D-dimer at the time of PTE diagnosis. A larger right ventricular diameter was associated with a greater need for oxygen support. CONCLUSION: Point-of-care echocardiography is a valuable tool for the risk assessment of COVID-19 patients with pulmonary embolism. Right ventricular size stood out as a significant marker of disease severity.

A Proposed Approach for the Management of Clot-in-Transit.

Clot-in-transit (CIT) is defined as a mobile echogenic material in the right atrium or ventricle as observed on ultrasound. A right heart free-floating thrombus is unusual when there is no structural disease of the heart or atrial fibrillation. Cardiopulmonary collapse and quick death can come from CIT, which occurs when a blood clot moves from the heart to the lungs. There are some clinical case reports of a large volume thrombus that was freely floating in the right heart in an asymptomatic patient, and the best therapeutic options are uncertain. Although several trials have been conducted on the treatment of CIT, clinical judgment is still used to determine the best treatment for right heart thrombus (RHT), especially when associated with pulmonary embolism (PE). In this review article, we discuss various diagnostic modalities and treatment options for this rare malady. We studied in detail their clinical impact on patients according to past research studies.