Standardized training in lung ultrasound is lacking. Given time constraints and challenges in accessing training, there is a need for condensed, focused training programs. This study aims to assess the effect of a targeted, condensed two hour training session on the competency of intensive care unit (ICU) healthcare professionals in interpreting lung ultrasound clips.

This is a multicenter prospective study in ICU healthcare professionals from six centers. Subjects received a two hour lung ultrasound training: a lecture on principles and recognition of (patho)physiological patterns followed by hands-on training. Subjects competency was tested using twenty pre-recorded lung ultrasound clips before and after training. Retainment of knowledge was tested after six to twelve months in a subset of subjects. Subjects were deemed competent if they reached a test score ≥80%.

Sixty-six subjects (49% intensivist, 44% with no lung ultrasound experience) were included. 61 subjects (92%) reached the predetermined competency level after training. After the training, the highest percentage of subjects (n = 27, 97%) who reached the competency threshold were those with no prior experience in lung ultrasound. Post-test scores were significantly higher than pre-test scores (87%, 95% CI (86, 89) vs 76%, 95% CI (73, 79), p < 0.001) with a median improvement of 9, 95% CI (7, 11) percentage points. After six to twelve months all retested subjects (n = 12) maintained competency.

A short two hour training program may be sufficient for ICU healthcare professionals to achieve competency in lung ultrasound interpretation, even for subjects with no prior lung ultrasound experience. Further studies are needed to validate these findings in different settings and assess competency in bedside ultrasound acquisition.

Background/Objectives: Acute heart failure (AHF) is a common cause of emergency department (ED) referral. Different guidelines aim to optimise this condition, but the evidence is poor for most indications regarding AHF. In this paper, we aim to (i) identify the five most interesting topics in AHF management, (ii) compare guidelines, and (iii) give the reader the best advice on how to manage AHF in each topic. Methods: The working group (WG) identified ten critical topics in AHF management using a Delphi method and submitted them to ITEMS, a national group of ED physicians that ranked them. The WG selected the five highest-ranked topics and performed a critical reappraisal of guidelines. Lastly, the WG prepared the answers for ED physicians according to the guidelines and comparisons of studies. Results: The WG identified five topics for ED patients with AHF: (i) what is the optimal oxygen and ventilatory support, (ii) what is the optimal dose and administration modality of diuretics, (iii) what is the role of inotropes and vasopressors, (iv) what therapeutic strategies are suggested for diuretic refractoriness, and (v) what is the diagnostic role of lung ultrasound. For each topic, the WG identified, summarised, and compared the indications provided by each guideline, generating advice for ED management of AHF after a critical literature reappraisal. Conclusions: We highlighted the differences among guidelines dealing with AHF and developed the five best recommendations to assist ED physicians in determining the optimal approach for the ED management of AHF and to suggest future research directions.

To provide an international expert consensus on technical aspects and clinical applications of quantitative lung ultrasound in adult, paediatric and neonatal intensive care.

The European Society of Intensive Care (ESICM) and the European Society of Paediatric and Neonatal Intensive Care (ESPNIC) endorsed the project. We selected an international panel of 20 adult, paediatric and neonatal intensive care experts with clinical and research expertise in quantitative lung ultrasound, plus two non-voting methodologists. Fourteen clinical questions were proposed by the chairs to the panel, who voted for their priority (1-9 Likert-type scale) and proposed modifications/supplementing (two-round vote). All the questions achieved the predefined threshold (mean score > 5) and 14 groups of 3 mixed adult/paediatric experts were identified to develop the statements for each clinical question; predefined groups of experts in the fields of adult and paediatric/neonatal intensive care voted statements specific for these subgroups. An iterative approach was used to obtain the final consensus statements (two-round vote, 1-9 Likert-type scale); statements were classified as with agreement (range 7-9), uncertainty (4-6), disagreement (1-3) when the median score and ≥ 75% of votes laid within a specific range.

A total of 46 statements were produced (4 adults-only, 4 paediatric/neonatal-only, 38 interdisciplinary); all obtained agreement. This result was also achieved by acknowledging in the statements the current limitations of quantitative lung ultrasound.

This consensus guides the use of quantitative lung ultrasound in adult, paediatric and neonatal intensive care and helps identify the fields where further research will be needed in the future.

The use of non-invasive respiratory support (NIRS) for acute respiratory failure (ARF), particularly hypoxemic respiratory failure, has advanced in recent years, especially during the COVID-19 pandemic. NIRS modalities like high-flow nasal cannula (HFNC), continuous positive airway pressure (CPAP), and non-invasive ventilation (NIV) have shown efficacy, though evidence is inconsistent, especially for "de novo" acute hypoxemic respiratory failure (AHRF). This review outlines the physiological rationale for NIRS and offers practical guidance on tailoring treatment to individual patients. Successful AHRF management with NIRS requires a personalized approach, guided by clinical expertise. Further research is needed to refine patient selection and optimize NIRS application.

Background: Upper abdominal surgeries exceeding two hours and operated in a lateral decubitus position present an "intermediate" risk for pulmonary complications. The objectives of this study were to observe the sonographic and clinical changes during and after surgeries with one recruitment maneuver (RM) performed intraoperatively before extubation. Methods: Laparoscopic nephrectomy patients were randomized into pre-extubation single RM (Group RM) and control (Group NoRM) groups. The LUS (Lung Ultrasound Score) was evaluated after intubation (T1), at the end of surgery before the RM (T2), after the RM but before extubation (T3), and 30 min after arrival to the Post-Anesthesia Care Unit (T4) in Group RM; in Group NoRM, it was evaluated at the T1, T2, and T4 time points. The primary outcome was the effect on the pre-extubation LUS (T2 in Group NoRM versus T3 in Group RM). The secondary outcomes included the effects on the T4 LUS, PPC occurrence, and PaO2/FiO2 ratios, and the sensitivity and specificity of the LUS in predicting PPCs. Results: The data of 54 patients were analyzed. The pre-extubation LUS was significantly lower in Group RM (16 (12.5, 17) vs. 18 (17, 20), p < 0.001). The T4 LUS was only different in the upper zones in the dependent lung (2 (1, 3.5) in Group RM vs. 4 (3, 4.5) in Group NoRM, p = 0.01). The perioperative PaO2/FiO2 ratios were similar (p > 0.05). The pre-extubation LUS exhibited 91% sensitivity (p = 0.04), whereas the T4 LUS sensitivity was 82% (p = 0.01). The PPC risk was 10-fold higher in patients with a pre-extubation LUS exceeding 19. Conclusions: A pre-extubation single RM instantly increases the LUS. However, this does not persist postoperatively or diminish respiratory complications. More importantly, the LUS was found to be a sensitive tool for predicting PPCs when performed just before extubation.

In the last two decades, there has been an increased interest in the application of lung ultrasound (LUS), especially intraoperatively, owing to its safety and simple approach to detecting and assessing pulmonary nodules. This review focuses on recent advancements in intraoperative lung ultrasound in detecting lung nodules. A systematic search was conducted using databases such as PubMed and Google Scholar. Keywords included "Lung ultrasound", "intraoperative lung ultrasound", and "video-assisted transthoracic surgery (VATS)". Articles published between 1963 and 2024 in peer-reviewed journals were included, focusing on the ones from the 2000s. Data on methodology, key findings, and research gaps were reviewed. Results indicated a significant advantage of intraoperative lung ultrasound (ILU) in the assessment of pulmonary nodules. ILU offers a noninvasive, real-time imaging modality that demonstrates up to 100% accuracy in detecting pulmonary nodules, with shorter time needed compared to other modalities, as well as less intraoperative periods and postoperative complications. However, some disadvantages were detected, such as operator dependency and a lack of specificity and knowledge of specific signs, as well as assisted localization via percutaneous puncture and its correct interpretation. The findings suggest that ILU has a promising future in pulmonary surgeries such as LUS-VATS but needs to be engaged more in clinical applications and modified with new techniques such as artificial intelligence (AI).

Accurate prognosis at first treatment for bovine respiratory disease (BRD) is essential for timely interventions and management decisions. This cross-sectional observational study evaluated 819 commercial beef feedyard cattle at chute-side for first BRD treatment. Logistic regression models examined potential associations between two outcomes-first treatment failure (requiring additional treatment) and unfinished treatment (due to mortality or culling)-and several explanatory variables, including sex, days on feed, bodyweight, breed, pulse oximetry, lung auscultation scores, and ultrasound lung scores (ULS) measured in the caudo-dorsal lung region. Animals that ultimately did not finish treatment were significantly more likely to present a ULS of 5 (74%) compared with those scored 1-4 (18-38%). Similarly, cattle with a ULS of 5 had a much higher probability of first treatment failure (74%) than those with scores of 1-3 (35-41%). Moreover, three or more B-lines in the ultrasound image or a "moth sign" finding were both strongly associated with increased probability of negative outcomes. These results highlight key ultrasound-based and demographic factors that serve as practical prognostic indicators for cattle at the onset of BRD treatment.

Central venous catheters (CVCs) and arterial catheters (ACs) are indispensable tools in modern healthcare, enabling life-saving therapies. However, they carry risks of complications such as bloodstream infections, thrombosis, and procedural mishaps, which impact patient safety and healthcare costs.1 Nurse-driven central line insertion (NDCLI) programs offer a proactive approach to address these challenges by empowering trained vascular access nurses to perform CVC and AC insertions.2 This 4-year follow-up builds on the initial publication, A Vascular Access Team's Journey to Central Venous Catheter and Arterial Line Placement, highlighting first-attempt success and the low-insertion complication rates of an NDCLI program at a community hospital. The program achieved a 91.25% first-attempt success rate and minimal complications, including a single pneumothorax across 812 insertions. Notably, the addition of midthigh femoral peripherally inserted central catheters (MTFPICCs) addressed critical gaps in vascular access for patients with central vessel occlusions, showcasing the program's adaptability and innovation. This follow-up underscores the value of NDCLI programs in improving efficiency, reducing delays, and enhancing patient outcomes. It also explores the potential for expanding the scope of practice to include other advanced vascular access devices. As the complexity of patient care evolves, NDCLI programs represent a transformative model for leveraging nursing expertise in vascular access, fostering collaboration, and standardizing best practices.

Quantitative lung ultrasound is increasingly being used in neonatology. The aim of this study is to identify the lung ultrasound scores (LUS) available for use in neonates, describe their characteristics and determine which LUS are most used and validated.

A systematic review of the literature was conducted following PRISMA-S (Preferred Reporting Items for Systematic Reviews and Meta-analysis Protocols extension for reporting literature searches in systematic reviews) guidelines. Articles describing LUS in newborn animals and human neonates, published up to March 2024, were searched in the PubMed and Embase databases.

Out of 757 identified studies, 121 were included. Most of the articles were published in the past 5 years, predominantly by European investigators. They described 32 different LUS. Only 10 (31.4%) of these LUS had undergone at least one validation attempt and only 15 (48.4%) used the four-step scoring scale (i.e. scored from 0 to 3) based on classical lung ultrasound patterns originally described and well established in adult critical care medicine. The most common (49 (40.5%) of all the articles) neonatal score (published by Brat et al. in 2015) was based on this classical grading system. The most commonly used score was also validated using the greatest number of techniques and applied to all major neonatal respiratory disorders. Its simplified version is used to analyse six chest areas (anterior and lateral) to guide surfactant administration, while its extended version includes 10 areas by adding four posterior ones.

The most commonly used and validated score, consistent with adult critical care practice, should be the standard for assessing lung aeration in neonates.

Lung ultrasound (LUS) has proven valuable in the initial assessment of coronavirus disease 2019 (COVID-19), but its role in detecting pulmonary fibrosis following intensive care remains unclear. This study aims to assess the presence of pulmonary sequelae and fibrosis-like changes using LUS in survivors of severe COVID-19 pneumonia one month after discharge.

We prospectively enrolled patients with severe COVID-19 who required mechanical ventilation in the intensive care unit (ICU) and conducted LUS assessments from admission to the outpatient visit after discharge. We tracked changes in key LUS findings and applied our proprietary LUS scoring system. To evaluate LUS accuracy, we correlated measured LUS values with computed tomography scores.

We evaluated B-line presence, pleural thickness, and consolidation in 14 eligible patients. The LUS scores exhibited minimal changes, with values of 19.1, 19.2, and 17.5 at admission, discharge, and the outpatient visit, respectively. Notably, the number of B-lines decreased significantly, from 1.92 at admission to 0.56 at the outpatient visit (p<0.05), while pleural thickness increased significantly, from 2.05 at admission to 2.48 at the outpatient visit (p≤0.05).

This study demonstrates that LUS can track changes in lung abnormalities in severe COVID-19 patients from ICU admission through to outpatient follow-up. While pleural thickening and B-line patterns showed significant changes, no correlation was found between LUS and high-resolution computed tomography fibrosis scores. These findings suggest that LUS may serve as a supplementary tool for assessing pulmonary recovery in severe COVID-19 cases.

Lung ultrasound (LUS) has become a crucial part of the investigative tools available in the management of critically ill patients, both within the intensive care unit setting and in prehospital medicine. The increase in its application, in part driven by the COVID-19 pandemic, along with the easy access and use of mobile and handheld devices, allows for immediate access to information, reducing the need for other radiological investigations. LUS allows for the rapid and accurate diagnosis and grading of respiratory pathology, optimisation of ventilation, assessment of weaning, and monitoring of the efficacy of surfactant therapies. This, however, must occur within the framework of accreditation to ensure patient safety and prevent misinterpretation and misdiagnosis. This narrative review aims to outline the current uses of LUS within the context of published protocols, associated pathologies, LUS scoring systems, and their applications, whilst exploring more novel uses.

To describe lung ultrasound findings in children with respiratory failure on invasive mechanical ventilation (MV).

This is a longitudinal, observational, quantitative study conducted in the pediatric intensive care unit. Children with respiratory distress syndrome, aged between 6 months and 7 years, on invasive MV were included in the study. Lung ultrasound was performed using the BLUE protocol in the first 48 h of hospitalization and during ventilatory weaning.

Seventeen patients who presented a significant reduction in A lines were included in the study. B lines showed worsening, indicating possible pulmonary complications. The decrease in pleural sliding from 14 to 3 (p = 0.04) and in the bat sign from 10 to 5 (p = 0.002) was statistically significant. The stratospheric sign showed a favorable trend (reduction from 3 to 0), but the p value of 0.08 was not significant. There was a moderate negative correlation between MV time and A lines, while a moderate positive correlation was observed between MV time and A lines. Furthermore, a moderate negative correlation between MV time and bat sign was also significant.

It is indicated that bedside lung ultrasound is a valuable tool for monitoring and management of children on invasive MV, allowing the follow-up of critical pediatric patients during the hospitalization period.

Acute Kidney Injury (AKI) has an incidence of 20-50 % in patients admitted in Intensive Care Unit. As weaning failure is associated with increased morbidity, its prediction and understanding of its physiological basis holds extreme importance in guided management and prognostication of these patients. We conducted this prospective, observational, single - center study to evaluate the efficacy of transthoracic echocardiography (TTE) and lung ultrasonography (LUS) in predicting weaning failure in patients with AKI requiring mechanical ventilation.

We performed LUS and TTE before and 2 h after initiating spontaneous breathing trials (SBT) in 32 mechanically ventilated critically ill patients with AKI. Extubation was decided by an independent physician. LUS included global and anterior LUS scores. TTE included measurement of E/A and E/e' ratios to determine LV filling pressures.

Out of 32 patients included in this study, weaning failure was observed in 17 (n = 17, 53 %) patients (weaning success n = 15, 47%). Demographic and baseline laboratory parameters were comparable between the study groups. Fluid balance [+370 (250-530)] and SOFA score [8 (7-9)] on admission were significantly higher in weaning failure group (p < 0.001, p = 0.049). LUS scores and difference between LUS scores before and at the end of the SBT were significantly higher among the weaning failure group. The model consisting of baseline variables, SOFA score on the day of weaning and SBT induced changes in global lung score showed highest ability to predict weaning failure with AUC of 0.965, R2 = 61 %, p < 0.001.

In mechanically ventilated critically ill patients with AKI, LUS scores can predict weaning failure after SBT.

CTRI/2020/12/029565.

Lung ultrasound has been extensively used to assess the etiology of respiratory failure. Additionally, lung ultrasound-based scoring systems have been proposed to semi-quantify the loss of lung aeration in the ICU. The one most frequently used distinguishes four steps of progressive loss of aeration (scores from 0 to 3) and 3 scores mean tissue-like pattern. However, the burden of consolidation is not considered as tissue-like pattern is defined as 3 scores independently of its dimension. In this study, we present an ultrasound method for quantitative measurement of consolidation size and investigate the relationship between consolidation size and outcome in ICU patients with respiratory failure.

A total of 124 patients in ICU were prospectively enrolled and 13 patients were excluded due to failure to obtain LUS measurements. Among the remaining 111 patients, 17 patients were non-intubated, and 94 patients under sedation and analgesia were intubated. All patients underwent lung ultrasound examination for the measurement of lung consolidation size between 24 and 48 h after ICU admission. Lung consolidation size was assessed by consolidation area index (CA), which was determined by tracing the maximum cross-sectional area of the region of consolidation. The Cox-regression model was constructed for 28- and 90-day mortality.

Consolidation size was successfully evaluated in all patients. The CA was 24.2cm2[15.9-36.6] (median [25th -75th percentiles]). CA was negatively correlated with PaO2/FiO2 ratio (r=-0.26, P < 0.0001). Upon univariate and multivariate analysis, only CA [Odds ratio (OR) 1.04, 95% CI 1.01-1.08, P = 0.004] and APACHEII (OR 1.14, 95% CI 1.05-1.25, P = 0.002) were the risk factors for ICU mortality. Patients with substantial CA (> 29.4cm2) had a higher risk of death in 28-day [Hazard ratio (HR) 4.35, 95%CI 1.70-11.11; Log-rank P = 0.017] and 90-day mortality (HR 4.10, 95%CI 1.62-10.39; Log-rank P < 0.01).

The proposed CA parameter, determined by lung ultrasound, was readily accessible at the bedside. It is noteworthy that a larger CA was correlated with impaired oxygenation and increased mortality rates among ICU patients. Further investigation is required to establish the merits of incorporating CA into lung ultrasound assessments in the ICU.

ClinicalTrial.gov, Identifier NCT05647967, Date: Dec 13, 2022, retrospectively registered.

The value of routine bedside lung ultrasound (LUS) for predicting patient disposition during visits to the Emergency Department (ED) is difficult to quantify. We hypothesized that a simplified scoring of bedside-acquired LUS images for the triage of acute respiratory symptoms in the ED would be associated with patient disposition.

For this observational pragmatic study, we reviewed prospectively-collected bedside LUS images from patients presenting to the ED with acute respiratory symptoms. We agreed on a simplified LUS scoring approach (0-3). At least three reviewers blindly assessed the available LUS images for each patient and determined the worst score for each patient and the presence of individual LUS findings. The worst LUS score was used to classify patients' LUS-suggested hospital admission risk. We evaluated the agreement between reviewers and the predictive value of LUS findings for patient disposition.

204 patients were eligible, and 126 sets of images were available and scored. The most common LUS finding were isolated B-lines (63.5 % of LUS images), pleural thickening/irregularity (48.4 %), and diffuse B-lines (43.7 %). The patients' worst LUS score were 2 (43.5 %), 3 (26.1 %), 1 (20.7 %), and 0 (9.8 %). There was good agreement among reviewers on the worst LUS score (intra-class correlation coefficient 0.830, 95 % confidence interval (0.772-0.875)) and the LUS-suggested disposition (ICC 0.882, 95 % CI (0.846, 0.911)).

A simplified scoring of bedside-acquired LUS images from patients with acute respiratory symptoms at the emergency department reliably predicts patient disposition.

Point-of-care ultrasound (POCUS) has increasingly become an integral part of clinical practice, particularly in nephrology, where its use extends beyond renal assessment to include multi-organ evaluations. Despite challenges such as limited ultrasound training and equipment access, especially in low- and middle-income countries, the adoption of POCUS is steadily rising. This narrative review explores the growing role of multi-organ POCUS in nephrology, with applications ranging from the assessment of congestion phenotypes, cardiorenal syndrome, and hemodynamic acute kidney injury (AKI) to the evaluation of arteriovenous fistulas and electrolyte disorders. In nephrology, POCUS enhances clinical decision making by enabling rapid, bedside evaluations of fluid status, cardiac function, and arteriovenous access. Studies have demonstrated its utility in diagnosing and managing complications such as heart failure, cirrhosis, and volume overload in end-stage renal disease. Additionally, POCUS has proven valuable in assessing hemodynamic alterations that contribute to AKI, particularly in patients with heart failure, cirrhosis, and systemic congestion. This review highlights how integrating ultrasound techniques, including lung ultrasound, venous Doppler, and focused cardiac ultrasound, can guide fluid management and improve patient outcomes. With advancements in ultrasound technology, particularly affordable handheld devices, and the expansion of targeted training programs, the potential for POCUS to become a global standard tool in nephrology continues to grow, enabling improved care in diverse clinical settings.

This study aims to investigate the predictive effectiveness of bedside lung ultrasound score (LUS) in conjunction with rapid shallow breathing index (RSBI) and oxygenation index (P/F ratio) for weaning pediatric patients from mechanical ventilation.

This was a retrospective study. Eighty-two critically ill pediatric patients, who were admitted to the Pediatric Intensive Care Unit (PICU) and underwent mechanical ventilation from January 2023 to April 2024, were enrolled in this study. Prior to weaning, all patients underwent bedside LUS, with concurrent measurements of their RSBI and P/F ratio. Patients were followed up for weaning outcomes and categorized into successful and failed weaning groups based on these outcomes. Differences in clinical baseline data, LUS scores, RSBI and P/F ratios between the two groups were compared. The predictive value of LUS scores, RSBI and P/F ratios for weaning outcomes was assessed using receiver operating characteristic (ROC) curves and the area under the curve (AUC).

Out of the 82 subjects, 73 (89.02%) successfully weaned, while 9 (10.98%) failed. No statistically significant differences were observed in age, gender, BMI, and respiratory failure-related comorbidities between the successful and failed weaning groups (P > 0.05). Compared to the successful weaning group, the failed weaning group exhibited longer hospital and intubation durations, higher LUS and RSBI, and lower P/F ratios, with statistically significant differences (P < 0.05). An LUS score ≥ 15.5 was identified as the optimal cutoff for predicting weaning failure, with superior predictive power compared to RSBI and P/F ratios. The combined use of LUS, RSBI and P/F ratios for predicting weaning outcomes yielded a larger area under the curve, indicating higher predictive efficacy.

The LUS demonstrates a high predictive value for the weaning outcomes of pediatric patients on mechanical ventilation.

Lung ultrasound (LUS) has emerged as a crucial tool in the diagnosis and monitoring of acute respiratory failure, particularly in critically ill patients. In this case, a man in his late 50s presented to the emergency department with respiratory distress and rapidly deteriorated, requiring invasive ventilation and intensive care unit admission for septic shock and multiorgan dysfunction. LUS revealed extensive consolidation with linear-arborescent dynamic air bronchogram, specific for community-acquired and ventilator-associated pneumonia, with a global LUS score of 22, indicating significant severity. LUS demonstrated greater sensitivity and specificity compared to chest radiography, allowing for a more reliable and timely diagnosis. The use of LUS was especially valuable given the patient's hemodynamic instability, which made computed tomography unfeasible. As a portable, radiation-free imaging modality, LUS offers significant advantages over traditional methods, particularly in emergency and critical care settings, where rapid bedside assessments are essential for guiding treatment and ensuring continuous patient monitoring.

The number of vertical artefacts (VAs) in lung ultrasound (LUS) impacts patients' clinical management. This study aimed to demonstrate the influence of ultrasound settings on the number of VAs in patients under invasive mechanical ventilation (IMV).

Patients under IMV were recruited for LUS, including three breathing cycles with a motionless curvilinear probe on the thoracic region with the most VAs. Three experts in LUS were asked about the number of VAs at random, and blinded after altering the settings for a total of 20 test recordings per patient. The correlation between expert classifications was tested after grading the classifications. The number of VAs across clinicians was compared between baseline recordings and test condition recordings to determine statistical differences.

29 patients were enrolled with a median Sequential Organ Failure Assessment score of 6 (interquartile range (IQR) 3). IMV was mainly due to stroke (n=10) and pneumonia (n=6). LUS was made between days 1 and 6 (IQR). Baseline recordings showed a median of 2±2 VAs in inspiration and a median of 1±2 in expiration from a total of 3636 expert classifications, with a strong agreement within patients. A probe frequency of 8 MHz, artefact filtering, speckle reduction and frame average reduced the median VA number by one. A power of -20 dB and dynamic range of 32 dB abolished the VAs. A gain above 90% increased the median number of VAs by one.

In this in vivo study, the LUS settings influenced the VA number in IMV patients, after controlling for physiological and operator confounders.

Proficiency in basic lung ultrasound is highly recommended for clinicians in general and internal medicine. This article will review and provide guidance for novice users on how to use lung ultrasound in clinical practice, through a pathology-oriented approach. The authors recommend a 12-zone protocol and describe how to perform and apply it in clinical practice while examining patients with clinical suspicion for the following diseases: pleural effusion, heart failure, pneumonia (bacterial and viral), interstitial lung disease, and pneumothorax.

Lung ultrasound can be useful for the early diagnosis and treatment of respiratory complications. The combination of air and soft tissue confirms imaging artefacts that can contribute to differentiation between healthy and deteriorated lung tissue. Although non-human primates are often chosen as research models due to their anatomical and physiological similarity to humans, there is a lack of data on the use of lung ultrasound in these individuals. The aim of this study was to evaluate the contribution of ultrasound examinations of the thoracic region of Callithrix sp. for diagnosing pneumopathy. Parameters were obtained from 166 new world non-human primates of both sexes, aged between 1 and 15 years and weighing between 128 g and 680 g kept under human care at the Mucky Project in Itu, São Paulo. Thoracic ultrasound examinations were carried out using a LOGIQe-R7 device (GE, United States), with a 10-22 MHz linear transducer, at four points on the left and right antimeres. Among these 166 individuals, 72 had some kind of pulmonary alteration. Forty-one of the animals with pulmonary alterations diagnosed on ultrasound died and underwent necropsy. Histopathological examination showed that in half of the samples the lung tissue was compatible with some form of pneumopathy. Considering these cases, the pulmonary alterations diagnosed through thoracic ultrasound examination in Callithrix sp. can be correlated with the occurrence of pneumopathy, which is often asymptomatic. Lung ultrasound is an important tool for use in clinics to detect and monitor respiratory diseases and can save lives by enabling early treatment.

Point of Care Ultrasound (POCUS) is widely used to evaluate pleural apposition in acute disease; however, the prevalence of abnormal findings among emphysematous patients is unknown. The aim of the study was to characterize POCUS findings in advanced emphysema and correlate parenchymal and spirometric changes with abnormal POCUS results.

We retrospectively evaluated POCUS images obtained in hyperinflated COPD patients. Images were obtained in the 2nd intercostal space (upper lobes) and above diaphragm insertion (lower lobes). Pleural sliding was graded as "present" or "absent," and M-mode images graded as "seashore," "barcode," or "hybrid" patterns; patients were then assigned to four groups based on the combination of findings. Differences between pulmonary function testing and high-resolution CT were made by Chi Square or ANOVA testing, and association by Spearman's correlation. Agreement among three scorers (two pulmonologists and one radiologist) was assessed using Kappa statistics.

Our study included 48 patients with 159 lobes imaged. We found a substantial percentage of lobes had either barcode M-mode appearance (13.8 %) or indeterminate/absent lung sliding (20.3 %). We identified 87 lobes (54.7 %) that did not fit any typical definition for M-mode ultrasound findings. There was no strong association of abnormal ultrasound patterns with airflow obstruction or emphysema percentage. There was wide interrater variability among B-mode (0.20-0.611) and M-mode (0.24-0.049) among the three graders.

Hyperinflated patients often show abnormal pleural sliding appearance on POCUS, with a high false positive rate of barcode pattern. This should be considered when interpretation of POCUS drives therapeutic decisions.

Primary ciliary dyskinesia (PCD) and cystic fibrosis (CF) are respiratory conditions requiring regular chest radiography (CXR) surveillance to monitor pulmonary disease. However, CXR is insensitive for lung disease in CF and PCD. Lung ultrasound (LU) is a radiation-free alternative showing good correlation with severity of lung disease in CF but has not been studied in PCD.

Standardized, six-zone LU studies and CXR were performed on a convenience sample of children with PCD or CF during a single visit when well. LU studies were graded using the LU scoring system, while CXR studies received a modified Chrispin-Norman score. Scores were correlated with clinical outcomes.

Data from 30 patients with PCD and 30 with CF (median age PCD 11.5 years, CF 9.1 years) with overall mild pulmonary disease (PCD median FEV1 90% predicted, CF FEV1 100%) were analyzed. LU abnormalities appear in 11/30 (36%) patients with PCD and 9/30 (30%) with CF. Sensitivity, specificity, positive predictive, and negative predictive values for abnormal LU compared to the gold standard of CXR are 42%, 61%, 42%, and 61% in PCD, and 44%, 81%, 50%, and 77% in CF, respectively. Correlation between LU and CXR scores are poor for both diseases (PCD r = -0.1288, p = 0.4977; CF r = 0.0343, p = 0.8571), and LU score does not correlate with clinical outcomes in PCD.

The correlation of LU findings with CXR surveillance studies is poor in patients with mild disease burdens from PCD or CF, and LU scores do not correlate with clinical outcomes in PCD.

Background/Objective: A-lines and B-lines are key ultrasound markers that differentiate normal from abnormal lung conditions. A-lines are horizontal lines usually seen in normal aerated lungs, while B-lines are linear vertical artifacts associated with lung abnormalities such as pulmonary edema, infection, and COVID-19, where a higher number of B-lines indicates more severe pathology. This paper aimed to evaluate the effectiveness of a newly released lung ultrasound AI tool (ExoLungAI) in the detection of A-lines and quantification/detection of B-lines to help clinicians in assessing pulmonary conditions. Methods: The algorithm is evaluated on 692 lung ultrasound scans collected from 48 patients (65% males, aged: 55 ± 12.9) following their admission to an Intensive Care Unit (ICU) for COVID-19 symptoms, including respiratory failure, pneumonia, and other complications. Results: ExoLungAI achieved a sensitivity of 91% and specificity of 81% for A-line detection. For B-line detection, it attained a sensitivity of 84% and specificity of 86%. In quantifying B-lines, the algorithm achieved a weighted kappa score of 0.77 (95% CI 0.74 to 0.80) and an ICC of 0.87 (95% CI 0.85 to 0.89), showing substantial agreement between the ground truth and predicted B-line counts. Conclusions: ExoLungAI demonstrates a reliable performance in A-line detection and B-line detection/quantification. This automated tool has greater objectivity, consistency, and efficiency compared to manual methods. Many healthcare professionals including intensivists, radiologists, sonographers, medical trainers, and nurse practitioners can benefit from such a tool, as it assists the diagnostic capabilities of lung ultrasound and delivers rapid responses.

Diagnosis of pneumonia can be challenging, particularly the differential diagnosis of lower respiratory tract infection and pneumonia, acute respiratory failure, the diagnosis of nosocomial pneumonia and in case of treatment failure. As compared to conventional chest radiography and CT of the scan, sonography of the chest offers advantages. It could be demonstrated that it was even superior to chest radiography in the identification of pneumonic consolidations. Since most pneumonias affect the lower lobes and include the pleura, pneumonic substrates could be identified in up to 90% of cases despite the limited penetration depth of lung ultrasound. Sonography of the chest has become an established method in the diagnosis of both adult as well as in pediatric community-acquired pneumonia. In addition, it is particularly powerful when used within a point of care (POCUS) approach which also includes the evaluation of the heart. Finally, it appears to have significant potential also in the diagnosis of nosomomial pneumonia and in the evaluation of treatment response, both in the ward as in the ICU.

Lung ultrasonic B-lines have high accuracy in diagnosing extravascular lung water (ELW) but have not been systematically subcategorized to differentiate the varied etiologies of ELW. This brief communication describes subcategories of B-lines into "inflammatory" and "transudative" patterns, based on their location, pleural morphology and associated subpleural pathologies. This subcategorization was derived using information from trainees undergoing lung ultrasound training in the Learning Ultrasound in Critical Care program, pathophysiological principles and their corresponding ultrasound correlates. This subcategorization helped trainees differentiate inflammatory pathologies of ELW (e.g. pneumonia, acute respiratory distress syndrome) from transudative (congestive) pathologies (e.g. fluid overload, cardiac failure).

Purpose  A 4-step lung ultrasound (LUS) score has been previously used to quantify lung density. We compared 2 versions of this scoring system for distinguishing severe from moderate loss of aeration in ARDS: coalescence-based score (cLUS) vs. quantitative-based score (qLUS - >50% pleura occupied by artefacts). Materials and Methods   We compared qLUS and cLUS to lung density measured by quantitative CT scan in 12 standard thoracic regions. A simplified approach (1 scan per region) was compared to an extensive one (regional score computed as the mean of all relevant intercostal space scores). Results   We examined 13 conditions in 7 ARDS patients (7 at PEEP 5, 6 at PEEP 15 cmH2O-156 regions, 398 clips). Switching from cLUS to qLUS resulted in a change in interpretation in 117 clips (29.4%, 1-point reduction) and in 41.7% of the regions (64 decreases (range 0.2-1), 1 increase (0.2 points)). Regional qLUS showed very strong correlation with lung density (rs=0.85), higher than cLUS (rs=0.79; p=0.010). The agreement with CT classification in well aerated, poorly aerated, and not aerated tissue was moderate for cLUS (agreement 65.4%; Cohen's K coefficient 0.475 (95%CI 0.391-0.547); p<0.0001) and substantial for qLUS (agreement 81.4%; Cohen's K coefficient 0.701 (95%CI 0.653-0.765), p<0.0001). The agreement between single spot and extensive approaches was almost perfect (cLUS: agreement 89.1%, Cohen's kappa coefficient 0.840 (95%CI 0.811-0.911), p<0.0001; qLUS: agreement 86.5%, Cohen's kappa coefficient 0.819 (95%CI 0.761-0.848), p<0.0001). Conclusion   A LUS score based on the percentage of occupied pleura performs better than a coalescence-based approach for quantifying lung density. A simplified approach performs as well as an extensive one.

The Respiratory Intensive Care Assembly of the European Respiratory Society gathered in Berlin to organise the third Respiratory Failure and Mechanical Ventilation Conference in February 2024. The conference covered key points of acute and chronic respiratory failure in adults. During the 3-day conference ventilatory strategies, patient selection, diagnostic approaches, treatment and health-related quality of life topics were addressed by a panel of international experts. In this article, lectures delivered during the event have been summarised by early career members of the Assembly and take-home messages highlighted.

Lung imaging techniques are crucial for managing ventilated patients in pediatric intensive care units (PICUs). Bedside chest x-ray has limitations such as low sensitivity and radiation exposure risks. Recently, lung ultrasound has emerged as a promising technology offering advantages such as real-time monitoring and radiation-free imaging. However, the integration of lung ultrasound into clinical practice raises questions about its impact on chest x-ray prescriptions. This study aims to assess whether implementing lung ultrasound reduces reliance on chest x-rays for ventilated pediatric patients in the PICU. This before-and-after uncontrolled quality improvement project was conducted from January 2022 to December 2023 in a referral PICU. The study included three phases: retrospective evaluation, learning phase, and prospective evaluation. Patients aged under 14 years, intubated, and ventilated for ≤ 30 days were included. Lung ultrasound was performed using a standardized protocol, and chest x-rays were conducted as per clinical indications. During the study period, 430 patients were admitted to the PICU, with 142 requiring mechanical ventilation. Implementation of routine bedside lung ultrasound led to a 39% reduction in chest x-ray requests (p < 0.001). Additionally, there was a significant decrease in irradiation exposure and a 27% reduction in costs associated with chest x-rays.Conclusion: Routine bedside lung ultrasound is a valuable tool in the modern PICU, it reduces the number of chest x-rays, with reduced radiation exposure and a potential cost savings. What is known: • Bedside chest x-ray is the main imaging study in ventilated pediatric patients • Chest x-ray is a valuable tool in pediatric critical care but it is associated with irradiation exposure What is new: • Implementation of bedside lung ultrasound in pediatric critical care unites reduces the chest x-rays requests and therefore patient-irradiation.

Lung ultrasound can evaluate for pneumothorax but the accuracy of diagnosis depends on experience among physicians. This study aimed to investigate the sensitivity and specificity of intelligent lung ultrasound in comparison with chest x-ray, employing chest computed tomography (CT) as the gold standard for diagnosis of pneumothorax in critical ill patients.

This prospective, observational study included 75 dyspnea patients admitted to the Intensive Care Unit of the Fourth Affiliated Hospital of Soochow University from January 2021 to April 2023. Lung ultrasound images were collected using BLUE-plus protocol and analyzed by artificial intelligence software to identify the pleural line, with CT results serving as the gold standard for diagnosis. Pneumothorax was diagnosed based on either the disappearance of pleural slip sign or identification of lung point. Additionally, chest x-ray images and diagnostic results were also obtained during the same period for comparison.

The sensitivity and specificity of intelligent lung ultrasound in diagnosing pneumothorax were 79.4% and 85.4%, respectively. The sensitivity and specificity of x-ray diagnosis were 82.4% and 80.5%. Additionally, the diagnostic time for lung ultrasound was significantly shorter than that for x-ray examination.

Intelligent lung ultrasound has diagnostic efficiency comparable to that of x-ray examination but offers advantages in terms of speed.

Rat thoracic ultrasound (RATTUS) is a non-invasive, easy-to-perform method for the evaluation of the pleural space and lungs in pet rats. The aim of the article is to present species-specific differences in the sonographic diagnosis of pneumothorax (PTX) in pet rats.

In total, 158 client-owned pet rats were examined during the period from July 2023 to January 2024. PTX was diagnosed in 20 of the examined rats (13.25%, the age of the animals ranged from 2 months to 32 months (19.08 ± 6.93 months; mean ± SD) and their body weight ranged from 97 g to 885 g (461.27 ± 138.97 g; mean ± SD). Radiographic confirmation of PTX was performed in all these 20 rats, in the control group radiography was used to confirm that PTX was not present.

The lung point and the barcode sign was found in 7/20 animals with sensitivity of 33.3% (95% CI, 0.16-0.59) and specificity of 100% (95% CI, 0.97-1.0). The abnormal curtain sign was found in 19/20 of animals with the sensitivity of 95% (95% CI, 0.73-0.99.7) and the specificity of 89% (95% CI, 0.82-0.93). The abnormalities in the substernal access were in 17/20 of animals with the sensitivity of 85% (95% CI, 0.61-0.96) and the specificity of 71% (95% CI, 0.62-0.78).

In conclusion, RATTUS is a non-invasive method for the diagnosis of PTX in rats. Lung point and barcode sign are specific but not easily diagnosed signs. The curtain sign in RATTUS is not specific for PTX, as there are e.g. geriatric rats (rats older than 1,5 years) in which the abnormal curtain sign is visible without the presence of PTX. The presence of moderate to severe PTX can be assessed by the substernal approach based on the presence of cardiac displacement toward the collapsed lung lobe, and on evaluation of the lung inflation symmetry. This sign is not specific for PTX but in conjunction with other ultrasonic signs described makes the RATTUS a feasible tool for PTX diagnosis in rats.

Postoperative pulmonary complications (PPCs) are common in patients who undergo colorectal surgery. Studies have focused on how to accurately diagnose and reduce the incidence of PPCs. Lung ultrasound has been proven to be useful in preoperative monitoring and postoperative care after cardiopulmonary surgery. However, lung ultrasound has not been studied in abdominal surgeries and has not been used with wearable devices to evaluate the influence of postoperative ambulation on the incidence of PPCs.

To investigate the relationship between lung ultrasound scores, PPCs, and postoperative physical activity levels in patients who underwent colorectal surgery.

In this prospective observational study conducted from November 1, 2019 to August 1, 2020, patients who underwent colorectal surgery underwent daily bedside ultrasonography from the day before surgery to postoperative day (POD) 5. Lung ultrasound scores and PPCs were recorded and analyzed to investigate their relationship. Pedometer bracelets measured the daily movement distance for 5 days post-surgery, and the correlation between postoperative activity levels and lung ultrasound scores was examined.

Thirteen cases of PPCs was observed in the cohort of 101 patients. The mean (standard deviation) peak lung ultrasound score was 5.32 (2.52). Patients with a lung ultrasound score of ≥ 6 constituted the high-risk group. High-risk lung ultrasound scores were associated with an increased incidence of PPCs after colorectal surgery (logistic regression coefficient, 1.715; odds ratio, 5.556). Postoperative movement distance was negatively associated with the lung ultrasound scores [Spearman's rank correlation coefficient (r), -0.356, P < 0.05].

Lung ultrasound effectively evaluates pulmonary condition post-colorectal surgery. Early ambulation and respiratory exercises in the initial two PODs will reduce PPCs and optimize postoperative care in patients undergoing colorectal surgery.

A combination of prone positioning (PP) and venovenous extracorporeal membrane oxygenation (VV-ECMO) is safe, feasible, and associated with potentially improved survival for severe acute respiratory distress syndrome (ARDS). However, whether ARDS patients, especially non-COVID-19 patients, placed in PP before VV-ECMO should continue PP after a VV-ECMO connection is unknown. This study aimed to test the hypothesis that early use of PP during VV-ECMO could increase the proportion of patients successfully weaned from ECMO support in severe ARDS patients who received PP before ECMO.

In this prospective observational study, patients with severe ARDS who were treated with VV-ECMO were divided into two groups: the prone group and the supine group, based on whether early PP was combined with VV-ECMO. The proportion of patients successfully weaned from VV-ECMO and 60-day mortality were analyzed before and after propensity score matching.

A total of 165 patients were enrolled, 50 in the prone and 115 in the supine group. Thirty-two (64%) and 61 (53%) patients were successfully weaned from ECMO in the prone and the supine groups, respectively. The proportion of patients successfully weaned from VV-ECMO in the prone group tended to be higher, albeit not statistically significant. During PP, there was a significant increase in partial pressure of arterial oxygen (PaO2) without a change in ventilator or ECMO settings. Tidal impedance shifted significantly to the dorsal region, and lung ultrasound scores significantly decreased in the anterior and posterior regions. Forty-five propensity score-matched patients were included in each group. In this matched sample, the prone group had a higher proportion of patients successfully weaned from VV-ECMO (64.4% vs. 42.2%; P = 0.035) and lower 60-day mortality (37.8% vs. 60.0%; P = 0.035).

Patients with severe ARDS placed in PP before VV-ECMO should continue PP after VV-ECMO support. This approach could increase the probability of successful weaning from VV-ECMO.

ClinicalTrials.Gov: NCT04139733. Registered 23 October 2019.

Background: Diaphragmatic dysfunction correlates with weaning failure, highlighting the need to independently assess the diaphragm's effects on weaning. We modified the rapid shallow breathing index (RSBI), a predictor of successful weaning, by incorporating temporal variables into existing ultrasound-derived diaphragm index to create a simpler index closer to tidal volume. Methods: We conducted a prospective observational study of patients who underwent a spontaneous breathing trial in the medical intensive care unit (ICU) at Severance Hospital between October 2022 and June 2023. Diaphragmatic displacement (DD) and diaphragm inspiratory time (Ti) were measured using lung ultrasonography. The modified RSBI was defined as follows: respiratory rate (RR) divided by DD was defined as D-RSBI, and RR divided by the sum of the products of DD and Ti on both sides was defined as DTi-RSBI. Results: Among the sonographic indices, DTi-RSBI had the highest area under the receiver operating characteristic (ROC) curve of 0.774 in ROC analysis, and a correlation was found between increased DTi-RSBI and unsuccessful extubation in a multivariable logistic regression analysis (adjusted odds ratio 0.02, 95% confidence interval 0.00-0.97). Conclusions: The DTi-RSBI is beneficial in predicting successful weaning in medical ICU patients.

Lung ultrasonography (LUS) is a valuable diagnostic tool, but there is a shortage of LUS experts with extensive knowledge and significant experience in the field. Convolutional neural networks (CNNs) have the potential to mitigate this issue by facilitating computer-aided diagnosis.

We propose computer-aided system by a CNN-based method for LUS diagnosis. As the first consideration, we investigated pleural line and lung sliding. The pleural line indicates the position of pleura in an ultrasound image, and LUS is performed after first confirming the position of pleural line. Lung sliding defined as the movement of the pleural line, and the absence of this feature is associated with pneumothorax.

Our proposed method accurately detected pleural line and lung sliding, demonstrating its potential to provide valuable diagnostic information on lung lesions.

Chest radiographs in critically ill patients can be difficult to interpret due to technical and clinical factors. We sought to determine the agreement of chest radiographs and CT scans, and the inter-observer variation of chest radiograph interpretation, in intensive care units (ICUs).

Chest radiographs and corresponding thoracic computerised tomography (CT) scans (as reference standard) were collected from 45 ICU patients. All radiographs were analysed by 20 doctors (radiology consultants, radiology trainees, ICU consultants, ICU trainees) from 4 different centres, blinded to CT results. Specificity/sensitivity were determined for pleural effusion, lobar collapse and consolidation/atelectasis. Separately, Fleiss' kappa for multiple raters was used to determine inter-observer variation for chest radiographs.

The median sensitivity and specificity of chest radiographs for detecting abnormalities seen on CTs scans were 43.2% and 85.9% respectively. Diagnostic sensitivity for pleural effusion was significantly higher among radiology consultants but no specialty/experience distinctions were observed for specificity. Median inter-observer kappa coefficient among assessors was 0.295 ("fair").

Chest radiographs commonly miss important radiological features in critically ill patients. Inter-observer agreement in chest radiograph interpretation is only "fair". Consultant radiologists are least likely to miss thoracic radiological abnormalities. The consequences of misdiagnosis by chest radiographs remain to be determined.

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.

Lung ultrasound (LUS) in an emerging technique used in the intensive care unit (ICU). The derivative LUS aeration score has been shown to have associations with mortality in invasively ventilated patients. This study assessed the predictive value of baseline and early changes in LUS aeration scores in critically ill invasively ventilated patients with and without ARDS (Acute Respiratory Distress Syndrome) on 30- and 90-day mortality.

This is a post hoc analysis of a multicenter prospective observational cohort study, which included patients admitted to the ICU with an expected duration of ventilation for at least 24 h. We restricted participation to patients who underwent a 12-region LUS exam at baseline and had the primary endpoint (30-day mortality) available. Logistic regression was used to analyze the primary and secondary endpoints. The analysis was performed for the complete patient cohort and for predefined subgroups (ARDS and no ARDS).

A total of 442 patients were included, of whom 245 had a second LUS exam. The baseline LUS aeration score was not associated with mortality (1.02 (95% CI: 0.99 - 1.06), p = 0.143). This finding was not different in patients with and in patients without ARDS. Early deterioration of the LUS score was associated with mortality (2.09 (95% CI: 1.01 - 4.3), p = 0.046) in patients without ARDS, but not in patients with ARDS or in the complete patient cohort.

In this cohort of critically ill invasively ventilated patients, the baseline LUS aeration score was not associated with 30- and 90-day mortality. An early change in the LUS aeration score was associated with mortality, but only in patients without ARDS.

ClinicalTrials.gov, ID NCT04482621.

Lung ultrasound (LUS) is widely used as a diagnostic and monitoring tool in critically ill patients. Lung ultrasound score (LUSS) based on the examination of twelve thoracic regions has been extensively validated for pulmonary assessment. However, it has revealed significant limitations: when applied to heterogeneous lung diseases with intermediate LUSS pattern (LUSS 1 and 2), for instance, intra-observer consistency is relatively low. In addition, LUSS is time-consuming and a more rapid overview of the extent of lung pathology and residual lung aeration is often required, especially in emergency setting. We propose a Visual Lung Ultrasound Protocol (VLUP) as a rapid monitoring tool for patients with acute respiratory failure. It consists of a probe sliding along the mid-clavicular, mid-axillary and scapular lines in transversal scan. VLUP allows a visualization of a large portion of the antero-lateral and/or posterior pleural surface. Serial assessments of two clinical cases are recorded and visually compared, enabling rapid understanding of lung damage and its evolution over time. VLUP allows a semi-quantitative and qualitative point-of-care assessment of lung injury. Through this standardized approach it is possible to accurately compare subsequent scans and to monitor the evolution of regional parenchymal damage. VLUP enables a quick estimation of the quantitative-LUSS (qLUSS) as the percentage of pleura occupied by artifacts, more suitable than LUSS in inhomogeneous diseases. VLUP is designed as a standardized, point-of-care lung aeration assessment and monitoring tool. The purpose of the paper is to illustrate this new technique and to describe its applications.

Acute respiratory distress syndrome (ARDS) is a frequent cause of hypoxemic respiratory failure with a mortality rate of approximately 30%. Identifying ARDS subphenotypes based on "focal" or "non-focal" lung morphology has the potential to better target mechanical ventilation strategies of individual patients. However, classifying morphology through chest radiography or computed tomography is either inaccurate or impractical. Lung ultrasound (LUS) is a non-invasive bedside tool that can accurately distinguish "focal" from "non-focal" lung morphology. We hypothesize that LUS-guided personalized mechanical ventilation in ARDS patients leads to a reduction in 90-day mortality compared to conventional mechanical ventilation.

The Personalized Mechanical Ventilation Guided by UltraSound in Patients with Acute Respiratory Distress Syndrome (PEGASUS) study is an investigator-initiated, international, randomized clinical trial (RCT) that plans to enroll 538 invasively ventilated adult intensive care unit (ICU) patients with moderate to severe ARDS. Eligible patients will receive a LUS exam to classify lung morphology as "focal" or "non-focal". Thereafter, patients will be randomized within 12 h after ARDS diagnosis to receive standard care or personalized ventilation where the ventilation strategy is adjusted to the morphology subphenotype, i.e., higher positive end-expiratory pressure (PEEP) and recruitment maneuvers for "non-focal" ARDS and lower PEEP and prone positioning for "focal" ARDS. The primary endpoint is all-cause mortality at day 90. Secondary outcomes are mortality at day 28, ventilator-free days at day 28, ICU length of stay, ICU mortality, hospital length of stay, hospital mortality, and number of complications (ventilator-associated pneumonia, pneumothorax, and need for rescue therapy). After a pilot phase of 80 patients, the correct interpretation of LUS images and correct application of the intervention within the safe limits of mechanical ventilation will be evaluated.

PEGASUS is the first RCT that compares LUS-guided personalized mechanical ventilation with conventional ventilation in invasively ventilated patients with moderate and severe ARDS. If this study demonstrates that personalized ventilation guided by LUS can improve the outcomes of ARDS patients, it has the potential to shift the existing one-size-fits-all ventilation strategy towards a more individualized approach.

The PEGASUS trial was registered before the inclusion of the first patient, https://clinicaltrials.gov/ (ID: NCT05492344).