Diagnostic Value of Bedside Lung Ultrasonography in Pneumonia

Lung Ultrasound in Predicting Outcomes in Patients with COVID-19 Treated with Extracorporeal Membrane Oxygenation

Pulmonary involvement due to SARS-CoV-2 infection can lead to acute respiratory distress syndrome in patients with COVID-19. Consequently, pulmonary imaging is crucial for management of COVID-19. This study aimed to evaluate the prognostic value of lung ultrasound (LUS) with a handheld ultrasound device (HHUD) in patients with COVID-19 treated with extracorporeal membrane oxygenation (ECMO). Therefore, patients underwent LUS with a HHUD every two days until they were either discharged from the intensive care unit or died. The study was conducted at the University Hospital of Bonn's anesthesiological intensive care ward from December 2020 to August 2021. A total of 33 patients (median [IQR]: 56.0 [53-60.5] years) were included. A high LUS score was associated with a decreased P/F ratio (repeated measures correlation [rmcorr]: -0.26; 95% CI: -0.34, -0.15; p < 0.001), increased extravascular lung water, defined as fluid accumulation in the pulmonary interstitium and alveoli (rmcorr: 0.11; 95% CI: 0.01, 0.20; p = 0.030), deteriorated electrolyte status (base excess: rmcorr: 0.14; 95% CI: 0.05, 0.24; p = 0.004; pH: rmcorr: 0.12; 95% CI: 0.03, 0.21; p = 0.001), and decreased pulmonary compliance (rmcorr: -0.10; 95% CI: -0.20, -0.01; p = 0.034). The maximum LUS score was lower in survivors (median difference [md]: -0.35; 95% CI: -0.55, -0.06; p = 0.006). A cutoff value for non-survival was calculated at a LUS score of 2.63. At the time of maximum LUS score, P/F ratio (md: 1.97; 95% CI: 1.12, 2.76; p < 0.001) and pulmonary compliance (md: 18.67; 95% CI: 3.33, 37.15; p = 0.018) were higher in surviving patients. In conclusion, LUS with a HHUD enables continuous evaluation of cardiopulmonary function in COVID-19 patients receiving ECMO support therapy and provides prognostic value in determining the patients' likelihood of survival.

Ultrasound-guided puncture into newborn rat brain

Since the brain structure of neonatal rats was not fully formed during the first 4 days, it cannot be detected using ultrasound. The objective of this study was to investigate the use of ultrasound to guide puncture in the normal coronal brain structure and determine the puncture depth of the location of the cortex, hippocampus, lateral ventricle, and striatum of newborn rats of 5-15 days. The animal was placed in a prone position. The specific positions of the cortex, hippocampus, lateral ventricle, and striatum were measured under ultrasound. Then, the rats were punctured with a stereotaxic instrument, and dye was injected. Finally, the brains of rats were taken to make frozen sections to observe the puncture results. By ultrasound, the image of the cortex, hippocampus, lateral ventricle, and striatum of the rat can be obtained and the puncture depth of the cortex (8 days: 1.02 ± 0.12, 10 days: 1.02 ± 0.08, 13 days: 1.43 ± 0.05), hippocampus (8 days: 2.63 ± 0.07, 10 days: 2.77 ± 0.14, 13 days: 2.82 ± 0.09), lateral ventricle (8 days: 2.08 ± 0.04, 10 days: 2.26 ± 0.03, 13 days: 2.40 ± 0.06), and corpus striatum (8 days: 4.57 ± 0.09, 10 days: 4.94 ± 0.31, 13 days: 5.13 ± 0.10) can be accurately measured. The rat brain structure and puncture depth changed with the age of the rats. Ultrasound technology can not only clarify the brain structure characteristics of 5-15-day-old rats but also guide the puncture and injection of the rat brain structure. The results of this study laid the foundation for the future use of ultrasound in experimental animal models of neurological diseases.

POCUS in dyspnea, nontraumatic hypotension, and shock; a systematic review of existing evidence

BACKGROUND

Point-of-care ultrasound (POCUS) has been adopted as a powerful tool in acute medicine. This systematic review aims to critically appraise the existing literature on point-of-care ultrasound in respiratory or circulatory deterioration.

METHODS

Original studies on POCUS and dyspnea, nontraumatic hypotension, and shock from March 2002 until March 2022 were assessed in the PubMed and Embase Databases. Two reviewers independently screened articles for inclusion, extracted data, and assessed the quality of included studies using an established checklist.

RESULTS

We included 89 articles in this review. Point-of-care ultrasound in the initial workup increases the diagnostic accuracy in patients with dyspnea, nontraumatic hypotension and shock in the ED, ICU and medical ward setting. No improvement is found in patients with severe sepsis in the ICU setting. POCUS is capable of narrowing the differential diagnoses and is faster, and more feasible in the acute setting than other diagnostics available. Results on outcome measures are heterogenous. The quality of the included studies is considered low most of the times, mainly because of performance and selection bias and absence of a gold standard as the reference test.

CONCLUSION

We conclude that POCUS contributes to a higher diagnostic accuracy in dyspnea, nontraumatic hypotension, and shock. It aides in narrowing the differential diagnoses and shortening the time to correct diagnosis and effective treatment.

TRIAL REGISTRY

INPLASY; Registration number: INPLASY202220020; URL: https://inplasy.com/.

Diagnostic Accuracy of Lung Ultrasound in Patients with Community-Acquired Pneumonia: A Single Center Observational Study

BACKGROUND: Pneumonia is a prevailing and severe infectious disease that can lead to increased fatality. AIM: We conducted this study to assess the role of lung ultrasound (LUS) in the diagnosis of community-acquired pneumonia (CAP) in comparison to CXR and CT Chest. METHODS: An observational study on 120 patients with suspected CAP was done in the ICU of the Critical care department at Cairo University Hospital. Clinical and laboratory data were recorded on admission including different scoring systems (SOFA, APACHE II, confusion, uremia, respiratory rate and blood pressure 65, and pulmonary severity index). All patients, within 6 h of admission, were investigated by a LUS, CXR, and CT Chest. All imaging techniques were repeated after 48 h if the initial CT chest was negative. RESULTS: The study population had a mean age of 70.6 ± 6.9-years-old, most of them were male (75.8%). Using CT chest as a reference imaging tool to confirm the diagnosis of pneumonia, LUS showed 94.1% sensitivity, 97.1% specificity, positive predictive value (PPV) 98.8%, negative predictive value (NPV) 87.2%, accuracy 95.0%, and area under a curve (AUC) 0.92. LUS was found to be a highly significant imaging tool in predicting diagnosis of pneumonia (p < 0.001). Chest X-ray had 69.4% sensitivity, 94.3% specificity, PPV 96.7%, NPV 55.9%, 76.6% accuracy, and AUC 0.6 in the detection of pneumonia. CXR was found to be an insignificant Imaging tool in predicting diagnosis of pneumonia (P = 0.19). CONCLUSION: LUS is a very promising, sensitive, and feasible imaging tool in the diagnosis of CAP in comparison with CT chest.

Diagnostic value of pulmonary ultrasound in acute exacerbation of chronic obstructive pulmonary disease: A pilot study

BACKGROUND

To evaluate the value of the pulmonary ultrasound for the diagnosis of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in emergency departments (EDs).

MATERIALS AND METHODS

Between January 2018 and December 2019, patients admitted to the ED of Shanxi Provincial People's Hospital for suspected AECOPD were prospectively included in this study. Pulmonary ultrasound was performed using a linear transducer. The pulmonary ultrasound findings were evaluated for further discrimination for patients with AECOPD. Then, the diagnostic performance of pulmonary ultrasound was estimated and calculated. The clinical characteristics between groups with and without pneumonia were compared.

RESULTS

A total of 53 patients with AECOPD were included in the final analysis. For diagnosis of AECOPD due to pneumonia, ultrasound findings, such as consolidation, slightly rough pleural line, or irregular and interrupted pleural line had a sensitivity of 92.3% and a specificity of 86.7%. For diagnosis of AECOPD complicating pulmonary fibrosis, fringed pleural line had a sensitivity of 100% and a specificity of 97.5%. In addition, patients with pleural effusion (n=19) or pneumothorax (n=1) were correctly identified and wavy or bulging pleural lines were common in patients with AECOPD (58.5%, 31/53).

CONCLUSION

Ultrasound findings could offer further discrimination for AECOPD complications and other pathological conditions, such as pneumonia, pulmonary fibrosis, pleural effusion, and pneumothorax in EDs.

Diagnostic Performance of Ultrasonography in Patients With Pneumonia: An Updated Comparative Systematic Review and Meta-analysis

Objectives:

A chest radiograph (CXR) is still the preferred diagnostic method when pneumonia is suspected, although the sensitivity is relatively low. The aim of this study was to compare the diagnostic sensitivity, specificity, and accuracy of ultrasonography (US) for the diagnosis of community-acquired pneumonia (CAP), compared with CXR.

Materials and Methods:

A principled search was conducted to identify original English articles using PubMed, EMBASE, Web of Science, Scopus, and the Cochrane library, with the end date of October 2020. A combination of keywords, such as “ultrasound” or “ultrasonography,” “pneumonia,” “sensitivity,” and “specificity,” was used. Methodologic quality was assessed using Quality Assessment of Diagnostic Accuracy Studies 2 criteria. Statistical analysis was completed on the resulting study data.

Results:

The search produced 16 eligible articles that reported on 2040 patients. The overall pooled sensitivity for US and CXR, to diagnose pneumonia, was 0.96 and 0.65, respectively. The overall pooled specificity for US and CXR was 0.85 and 0.81, respectively. The overall pooled positive likelihood ratio for US and CXR was 9.74 and 3.67, respectively. The negative likelihood ratio for US and CXR was 0.05 and 0.42, respectively. In addition, summary receiver operative characteristics areas under the curve were 0.98 for US and 0.77 for CXR.

Conclusion:

This review demonstrated that lung US is a useful technique for the diagnosis of pneumonia. This diagnostic method can be used by emergency physicians with high accuracy, sensitivity, and specificity. Among an elderly population, this diagnostic method may be a better choice than CXR. The rapid performance of lung US may facilitate a quick, cost-effective, and safe diagnosis of this potentially fatal disease.

Advanced Meta-Heuristics, Convolutional Neural Networks, and Feature Selectors for Efficient COVID-19 X-Ray Chest Image Classification

The chest X-ray is considered a significant clinical utility for basic examination and diagnosis. The human lung area can be affected by various infections, such as bacteria and viruses, leading to pneumonia. Efficient and reliable classification method facilities the diagnosis of such infections. Deep transfer learning has been introduced for pneumonia detection from chest X-rays in different models. However, there is still a need for further improvements in the feature extraction and advanced classification stages. This paper proposes a classification method with two stages to classify different cases from the chest X-ray images based on a proposed Advanced Squirrel Search Optimization Algorithm (ASSOA). The first stage is the feature learning and extraction processes based on a Convolutional Neural Network (CNN) model named ResNet-50 with image augmentation and dropout processes. The ASSOA algorithm is then applied to the extracted features for the feature selection process. Finally, the Multi-layer Perceptron (MLP) Neural Network's connection weights are optimized by the proposed ASSOA algorithm (using the selected features) to classify input cases. A Kaggle chest X-ray images (Pneumonia) dataset consists of 5,863 X-rays is employed in the experiments. The proposed ASSOA algorithm is compared with the basic Squirrel Search (SS) optimization algorithm, Grey Wolf Optimizer (GWO), and Genetic Algorithm (GA) for feature selection to validate its efficiency. The proposed (ASSOA + MLP) is also compared with other classifiers, based on (SS + MLP), (GWO + MLP), and (GA + MLP), in performance metrics. The proposed (ASSOA + MLP) algorithm achieved a classification mean accuracy of (99.26%). The ASSOA + MLP algorithm also achieved a classification mean accuracy of (99.7%) for a chest X-ray COVID-19 dataset tested from GitHub. The results and statistical tests demonstrate the high effectiveness of the proposed method in determining the infected cases.

Point-of-care lung ultrasound for the assessment of pneumonia: a narrative review in the COVID-19 era

In the coronavirus disease-2019 (COVID-19) era, point-of-care lung ultrasound (LUS) has attracted increased attention. Prospective studies on LUS for the assessment of pneumonia in adult patients were extensively carried out for more than 10 years before this era. None of these prospective studies attempted to differentiate bacterial and viral pneumonia in adult patients using LUS. The majority of studies considered the LUS examination to be positive if sonographic consolidations or multiple B-lines were observed. Significant differences existed in the accuracy of these studies. Some studies revealed that LUS showed superior sensitivity to chest X-ray. These results indicate that point-of-care LUS has the potential to be an initial imaging modality for the diagnosis of pneumonia. The LUS diagnosis of ventilator-associated pneumonia in intensive care units is more challenging in comparison with the diagnosis of community-acquired pneumonia in emergency departments due to the limited access to the mechanically ventilated patients and the high prevalence of atelectasis. However, several studies have demonstrated that the combination of LUS findings with other clinical markers improved the diagnostic accuracy. In the COVID-19 era, many case reports and small observational studies on COVID-19 pneumonia have been published in a short period. Multiple B-lines were the most common and consistent finding in COVID-19 pneumonia. Serial LUS showed the deterioration of the disease. The knowledge and ideas on the application of LUS in the management of pneumonia that are expected to accumulate in the COVID-19 era may provide us with clues regarding more appropriate management.

Accuracy of Bedside Lung Ultrasound as a Rapid Triage Tool for Suspected Covid-19 Cases

OBJECTIVES

The novel coronavirus disease 2019 (Covid-19) outbreak began in China. The characteristic of the disease is development of pneumonia. We aimed to investigate the accuracy of bedside lung ultrasound (BLUS) for diagnosing Covid-19 pneumonia, and its effectiveness for the correct triage of patients with suspected Covid-19 in the emergency department (ED).

METHODS

This study was a prospective, cross-sectional cohort study. During their shifts, 3 accredited and certificated emergency physicians performed BLUS using BLUE protocol at the triage area of the ED on patients with suspected Covid-19. All of the patients underwent chest computed tomography. The BLUS findings were statistically compared with formal radiology reports of computed tomographies as the criterion standard for the diagnosis of Covid-19 pneumonia. Kolmogorov-Smirnov analysis, Shapiro-Wilk test, and Q-Q plots were performed with 95% confidence intervals (CIs) for statistical analysis.

RESULTS

A total of 72 patients were included in the study. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of BLUS were 96.9% (95% CI, 84.2%-99.9%), 92.3% (95% CI, 79.1%-98.3%), 84.3% (95% CI, 64.5%-94.1%), 98.6% (95% CI, 91.1%-99.8%), and 93.7% (95% CI, 85.3%-98.0%), respectively. The positive and negative predictive values were 84.3% (95% CI, 64.5%-94.1%) and 98.6% (95% CI, 91.1%-99.8%), respectively. The area under curve was found to be 0.946 (95% CI, 0.866-0.986; P < 0.0001).

CONCLUSIONS

Bedside lung ultrasound can be used to detect the presence of pulmonary involvement in suspected cases of Covid-19 for the effective triage of patients in the ED.

COVID-19 Assessment with Bedside Lung Ultrasound in a Population of Intensive Care Patients Treated with Mechanical Ventilation and ECMO

The COVID-19 pandemic has increased the need for an accessible, point-of-care and accurate imaging modality for pulmonary assessment. COVID-19 pneumonia is mainly monitored with chest X-ray, however, lung ultrasound (LUS) is an emerging tool for pulmonary evaluation. In this study, patients with verified COVID-19 disease hospitalized at the intensive care unit and treated with ventilator and extracorporal membrane oxygenation (ECMO) were evaluated with LUS for pulmonary changes. LUS findings were compared to C-reactive protein (CRP) and ventilator settings. Ten patients were included and scanned the day after initiation of ECMO and thereafter every second day until, if possible, weaned from ECMO. In total 38 scans adding up to 228 cineloops were recorded and analyzed off-line with the use of a constructed LUS score. The study indicated that patients with a trend of lower LUS scores over time were capable of being weaned from ECMO. LUS score was associated to CRP (R = 0.34; p < 0.03) and compliance (R = 0.60; p < 0.0001), with the strongest correlation to compliance. LUS may be used as a primary imaging modality for pulmonary assessment reducing the use of chest X-ray in COVID-19 patients treated with ventilator and ECMO.

Lung Ultrasound in a COVID Pandemic - Choosing wisely

This is an opinion piece on the role of POCUS in COVID‐19, with a focus on lung ultrasound. It is not an instructional essay. Crisis management in medicine has often been likened to crisis management in the aviation industry. The important difference between pilots and clinicians is that the clinician's life was not in imminent danger, should one fail. The clinician did not have the same emotional urgency as the pilot. The COVID‐19 pandemic has changed this, and clinicians are now faced with the need to make urgent decisions whilst exposed to some personal risk. Whether to embrace POCUS and lung ultrasound during this pandemic is an important decision. Whilst there are clear advantages, poorly considered overzealous uptake is not without hazard, opportunity cost and potential risk to patient and clinician.