Roberto Copetti

Lung Ultrasound in the Diagnosis and Follow-up of Community-Acquired Pneumonia: A Prospective, Multicenter, Diagnostic Accuracy Study

BACKGROUND The aim of this prospective, multicenter study was to define the accuracy of lung ultrasound (LUS) in the diagnosis of community-acquired pneumonia (CAP). METHODS Three hundred sixty-two patients with suspected CAP were enrolled in 14 European centers. At baseline, history, clinical examination, laboratory testing, and LUS were performed as well as the reference test, which was a radiograph in two planes or a low-dose CT scan in case of inconclusive or negative radiographic but positive LUS findings. In patients with CAP, follow-up between days 5 and 8 and 13 and 16 was scheduled. RESULTS CAP was confirmed in 229 patients (63.3%). LUS revealed a sensitivity of 93.4% (95% CI, 89.2%-96.3%), specificity of 97.7% (95% CI, 93.4%-99.6%), and likelihood ratios (LRs) of 40.5 (95% CI, 13.2-123.9) for positive and 0.07 (95% CI, 0.04-0.11) for negative results. A combination of auscultation and LUS increased the positive LR to 42.9 (95% CI, 10.8-170.0) and decreased the negative LR to 0.04 (95% CI, 0.02-0.09). We found 97.6% (205 of 211) of patients with CAP showed breath-dependent motion of infiltrates, 86.7% (183 of 211) an air bronchogram, 76.5% (156 of 204) blurred margins, and 54.4% (105 of 193) a basal pleural effusion. During follow-up, median C-reactive protein levels decreased from 137 mg/dL to 6.3 mg/dL at days 13 to 16 as did signs of CAP; median area of lesions decreased from 15.3 cm2 to 0.2 cm2 and pleural effusion from 50 mL to 0 mL. CONCLUSIONS LUS is a noninvasive, usually available tool used for high-accuracy diagnosis of CAP. This is especially important if radiography is not available or applicable. About 8% of pneumonic lesions are not detectable by LUS; therefore, an inconspicuous LUS does not exclude pneumonia.

Sonographic Interstitial Syndrome The Sound of Lung Water

Objective. Ultrasound lung comets (ULCs) now have an acknowledged correlation with extravascular lung water, but they present in different orders and numbers in different pathologic pulmonary entities. How these artifacts are created is not yet known, and the literature gives discordant hypotheses. Understanding their formation is the first step in understanding lung disease. The purpose of this study was to show the morphologic and genetic variability of interstitial lung disease studied with echography and thus to propose a unitary mechanism for the formation of ULCs. Methods. This study included 3 parts: (1) a retrospective analysis of echographic lung images of patients with interstitial syndrome; (2) an analysis of the literature for definitions of the size of the pulmonary lobule; and (3) an experimental model of different air‐water interfaces scanned with varying ultrasonic frequencies. Results. The retrospective analysis of echographic lung images included 176 patients with diffuse ULCs: 118 patients had acute pulmonary edema; 18 had acute lung injury/acute respiratory distress syndrome; and 40 were premature neonates with respiratory distress syndrome. Experimental models permitted us to discover that ring‐down artifacts are produced only by single and double layers of bubbles in specific structural settings. Conclusions. Reverberation between bubbles with a critical radius seems to be at the origin of ring‐down artifacts. Echographic manifestations of interstitial lung disease, whose genesis lies in the partial air loss of lobes and segments, are acoustic phenomena originating from variations in the tissue‐fluid relationship of the lung. A correlation between anatomopathologic characteristics and structures of sonographic artifacts could allow more rapid and noninvasive diagnoses.

Current role of emergency ultrasound of the chest.

Objective:Chest sonography has gained clinical significance in the diagnosis of various pulmonary, pleural, cardiac, and mediastinal emergency conditions. Therefore, the current role of emergency ultrasound are assessed. Data Source:A systematic literature search of MEDLINE database was performed to identify all studies dealing with transthoracic sonography/chest ultrasound in combination with pulmonary embolism, pneumothorax, pneumonia, pleural effusion, pulmonary edema, and lung contusion. The relevant sonographic studies between 1988 and 2010 were evaluated. Conclusions:The noninvasive ultrasound-based diagnosis is relatively portable permitting the technique to be performed at any time, in any place, and on any patient, an ideal method for emergency conditions. Sonography allows immediate diagnosis of pulmonary embolism, pneumothorax, pneumonia, pleural effusion as well as rib fracture, and it provides a basis for further diagnostic- and treatment-related decisions. The key sonographic features associated with these most common emergency chest diseases are illustrated herein.

Lung Ultrasound Accuracy in Respiratory Distress Syndrome and Transient Tachypnea of the Newborn

Background: Lung ultrasound (LUS) is a promising technique for the diagnosis of neonatal respiratory diseases. Preliminary data has shown a good sensitivity and specificity of LUS in the diagnosis of respiratory distress syndrome (RDS) and transient tachypnea of the newborn (TTN). Objective: The aim of this study was to calculate the sensitivity, specificity, and negative (NPV) and positive predictive value (PPV) of LUS for RDS and TTN, using an external reader blinded to the clinical condition. Design and Methods: Neonates with respiratory distress had a LUS within 1 h of admission. Images were uploaded and sent to the external reader, who made the ultrasound diagnosis according to the appearance of the images. The final clinical diagnosis was made according to all the available data, except LUS data. Sensitivity, specificity, PPV, and NPV were calculated considering the final clinical diagnosis as the gold standard. Results: Fifty-nine neonates were studied (mean gestational age: 33 ± 4 weeks, mean birth weight: 2,145 ± 757 g). Twenty-three infants had a final diagnosis of RDS and 30 of TTN. LUS showed a sensitivity of 95.6% and specificity of 94.4%, with a PPV of 91.6% and a NPV of 97.1% for RDS, and a sensitivity of 93.3% and specificity of 96.5% with a PPV of 96.5% and a NPV of 93.4% for TTN. Conclusions: LUS showed high sensitivity and specificity in diagnosing RDS and TTN.

The role of chest ultrasonography in the management of respiratory diseases: document II

Chest ultrasonography can be a useful diagnostic tool for respiratory physicians. It can be used to complete and widen the general objective examination also in emergency situations, at the patient’s bedside. The aim of this document is to promote better knowledge and more widespread use of thoracic ultrasound among respiratory physicians in Italy.This document II is focused on advanced approaches to chest ultrasonography especially in diagnosing sonographic interstitial syndrome with physical hypotheses about the genesis of vertical artifacts, differential diagnosis of cardiogenic pulmonary edema and non-cardiogenic pulmonary edema, raising diagnostic suspicion of pulmonary embolism, ultrasound characterization of lung consolidations and the use of ultrasonography to guide procedural interventions in pulmonology.Finally, document II focuses on chest ultrasonography as useful diagnostic tool in neonatal and pediatric care.

Early recognition of the 2009 pandemic influenza A (H1N1) pneumonia by chest ultrasound

IntroductionThe clinical picture of the pandemic influenza A (H1N1)v ranges from a self-limiting afebrile infection to a rapidly progressive pneumonia. Prompt diagnosis and well-timed treatment are recommended. Chest radiography (CRx) often fails to detect the early interstitial stage. The aim of this study was to evaluate the role of bedside chest ultrasonography (US) in the early management of the 2009 influenza A (H1N1)v infection.Methods98 patients who arrived in the Emergency Department complaining of influenza-like symptoms were enrolled in the study. Patients not displaying symptoms of acute respiratory distress were discharged without further investigations. Among patients with clinical suggestion of a community-acquired pneumonia, cases encountering other diagnoses or comorbidities were excluded from the study. Clinical history, laboratory tests, CRx, and computed tomography (CT) scan, if indicated, contributed to define the diagnosis of pneumonia in the remaining patients. Chest US was performed by an emergency physician, looking for presence of interstitial syndrome, alveolar consolidation, pleural line abnormalities, and pleural effusion, in 34 patients with a final diagnosis of pneumonia, in 16 having normal initial CRx, and in 33 without pneumonia, as controls.ResultsChest US was carried out without discomfort in all subjects, requiring a relatively short time (9 minutes; range, 7 to 13 minutes). An abnormal US pattern was detected in 32 of 34 patients with pneumonia (94.1%). A prevalent US pattern of interstitial syndrome was depicted in 15 of 16 patients with normal initial CRx, of whom 10 (62.5%) had a final diagnosis of viral (H1N1) pneumonia. Patients with pneumonia and abnormal initial CRx, of whom only four had a final diagnosis of viral (H1N1) pneumonia (22.2%; P < 0.05), mainly displayed an US pattern of alveolar consolidation. Finally, a positive US pattern of interstitial syndrome was found in five of 33 controls (15.1%). False negatives were found in two (5.9%) of 34 cases, and false positives, in five (15.1%) of 33 cases, with sensitivity of 94.1%, specificity of 84.8%, positive predictive value of 86.5%, and negative predictive value of 93.3%.ConclusionsBedside chest US represents an effective tool for diagnosing pneumonia in the Emergency Department. It can accurately provide early-stage detection of patients with (H1N1)v pneumonia having an initial normal CRx. Its routine integration into their clinical management is proposed.

Lung Ultrasound in Community-Acquired Pneumonia and in Interstitial Lung Diseases

Lung ultrasound (LUS) is an accurate tool for the diagnosis and follow-up of pneumonia in adults as well as in children. LUS is at least as accurate as chest radiography in diagnosing pneumonia. The most important parenchymal criterion is the positive air bronchogram within an echopoor area. Among pleural criteria, basal effusion was most often detected. The presence of multiple diffuse bilateral B-lines on lung examination indicates the interstitial syndrome (IS). For further differential diagnosis, an integrated consideration of history, clinical examination, LUS and echocardiography should be performed. LUS is an excellent tool for IS screening. Repeated LUS control examinations may reflect the dynamics of IS under therapy and so LUS may serve as a therapy guide.

Ultrasound performs better than radiographs

We applaud the British Thoracic Society (BTS) for its efforts to improve patient care through scientific evidence. We thus recognise the recent guidelines on pleural procedures and thoracic ultrasound (TUS) as an important attempt to develop a rational approach to chest sonography.1 However, we are concerned that the BTS has reached conclusions based on a less complete review of TUS. The guidelines state that ‘the utility of thoracic ultrasound for diagnosing a pneumothorax is limited in hospital practice due to the ready availability of chest x-rays (CXR) and conflicting data from published reports’.1 This conclusion appears to be based on a small (but landmark) study of 11 patients from 1986 to 1989, two small studies with only four pneumothoraces in …

Optic nerve ultrasound: artifacts and real images.

Sir: I read with great interest the papers of Geeraerts et al. [1, 2] on ultrasound evaluation of the optic nerve and its correlations with intracranial pressure. In my opinion, however, what the authors indicate as the optic nerve on ultrasound examination is an artifact (acoustic shadow), probably cast by the lamina cribrosa. The measurements that the authors report do not reflect the optic nerve sheath diameter, but the measurement of an artifactual image. Images of the optic nerve that are obtained with CT or MRI are very different from those obtained with ultrasound. The optic nerve is serpiginous and runs medially, while in these papers the optic nerve seems to run straight and centrally. To confirm our hypothesis we have identified optic nerve with the color Doppler. Since the central retinal artery and vein pass centrally through the optic nerve, color Doppler helps in the correct identification of the optic nerve. Figure 1 shows the artifact and the central retinal artery. It is evident that the direction of central retinal artery identifies the course of optic nerve. Figure 2 shows that in a normal subject the diameter of artifact is 59 mm, compatible with raised intracranial pressure, while the real diameter of the optic nerve, identified with color Doppler is normal (35 mm). The measurement must be done orthogonally to the nerve. Eye position affects the evidence of the artifact. The Fig. 3 shows in the same patient the optic nerve when the eye is in a central and lateral position. In a central position the artifact increases the diameter of the optic nerve. This is probably due to the incidence of ultrasound beam on the lamina cribrosa. Since other authors also performed the measurement of the artifact and not of the optic nerve [3–6], it seems to be obvious that the increased optic nerve diameter determines an increase of the acoustic shadow. However, in some patients without

Radiation exposure early in life can be reduced by lung ultrasound.

Affi liations: From the Division of Pulmonary and Critical Care Medicine (Dr Metersky), University of Connecticut School of Medicine; and the Music Department (Mr Bean), Central Connecticut State University. Financial/nonfi nancial disclosures: The authors have reported to CHEST that no potential confl icts of interest exist with any companies/organizations whose products or services may be discussed in this article. Correspondence to: Mark L. Metersky, MD, FCCP, Division of Pulmonary and Critical Care Medicine, University of Connecticut Health Center, 263 Farmington Ave, Farmington, CT 06030-1321; e-mail: Metersky@nso.uchc.edu