Giovanni Volpicelli

Sonographic diagnosis of pneumothorax

PurposeOver the last decade, the use of ultrasound as a technique to look for pneumothorax has rapidly evolved. This review aims to analyze and synthesize current knowledge on lung ultrasound targeted at the diagnosis of pneumothorax. The technique and its usefulness in different scenarios are explained, and its merits over conventional radiology are highlighted.MethodsA systematic literature search (1995–2010) was performed, involving PubMed, to describe the more recent scientific evidence on the topic. Moreover, this review is also a synopsis of experts’ opinion and personal clinical experience.Results and conclusionsUltrasound diagnosis of pneumothorax relies on the recognition of four sonographic artifact signs: the lung sliding, the B lines, the lung point, and the lung pulse. Combining these few signs, it is possible to accurately rule in or rule out pneumothorax at the bedside in several different clinical scenarios. Sensitivity of a lung ultrasound in the detection of pneumothorax is higher than that of conventional anterior–posterior chest radiography, and similar to that of computerized tomography. A major benefit of a lung ultrasound is that it can be used quickly to diagnose pneumothorax at the bedside in any critical situation, like cardiac arrest and hemodynamically unstable patients. Moreover, it can be used to detect radio-occult pneumothorax and to quantify the extension of the air layer. Advantages in terms of reduced complexity, feasibility at the bedside, and absence of exposure to ionizing radiation make lung ultrasound the method of choice in several common clinical situations.

Bedside ultrasound of the lung for the monitoring of acute decompensated heart failure.

PURPOSES Multiple artifacts B lines (B+) at transthoracic lung ultrasound have been proposed as a sonographic sign of pulmonary congestion. Our aim is to assess B+ clearance after medical treatment in acute decompensated heart failure (ADHF) and to compare the usefulness of sonography with other traditional tools in monitoring resolution of pulmonary congestion. METHODS Eighty-one patients with a diagnosis of ADHF were submitted to lung ultrasound and chest radiography at admission, and 70 of them underwent the same procedures as control group after 4.2 +/- 1.7 days of medical treatment. The ultrasound examination was performed with 11 scans on as many anterolateral thoracic areas (6 on the right side and 5 on the left side). Then, we calculated a sonographic score counting the B+ scans and compared it with radiologic score for extravascular lung water, clinical, and plasma brain natriuretic peptide improvement. MAIN RESULTS All patients showed B+ pattern at admission and significant clearing after treatment, with median number of 8 positive scans (range, 3-9 scans) vs 0 (range, 0-7 scans) (P < .05). Our sonographic score showed positive linear correlation with radiologic score (r = 0.62; P < .05), clinical score (r = 0.87; P < .01), and brain natriuretic peptide levels (r = 0.44; P < .05). Delta Sonographic score correlated with Delta clinical (r = 0.55; P < .05) and radiologic (r = 0.28; P < .05) scores. CONCLUSIONS B line pattern mostly clears after adequate medical treatment of ADHF and represents an easy-to-use alternative bedside diagnostic tool for clinically monitoring pulmonary congestion in patients with ADHF.

Accuracy of Point-of-Care Multiorgan Ultrasonography for the Diagnosis of Pulmonary Embolism

BACKGROUND Presenting signs and symptoms of pulmonary embolism (PE) are nonspecific, favoring a large use of second-line diagnostic tests such as multidetector CT pulmonary angiography (MCTPA), thus exposing patients to high-dose radiation and to potential serious complications. We investigated the diagnostic performance of multiorgan ultrasonography (lung, heart, and leg vein ultrasonography) and whether multiorgan ultrasonography combined to Wells score and D-dimer could safely reduce MCTPA tests. METHODS Consecutive adult patients suspected of PE and with a Wells score > 4 or a positive D-dimer result were prospectively enrolled in three EDs. Final diagnosis was obtained with MCTPA. Multiorgan ultrasonography was performed before MCTPA and considered diagnostic for PE if one or more subpleural infarcts, right ventricular dilatation, or DVT was detected. If multiorgan ultrasonography was negative for PE, an alternative ultrasonography diagnosis was sought. Accuracies of each single-organ and multiorgan ultrasonography were calculated. RESULTS PE was diagnosed in 110 of 357 enrolled patients (30.8%). Multiorgan ultrasonography yielded a sensitivity of 90% and a specificity of 86.2%, lung ultrasonography 60.9% and 95.9%, heart ultrasonography 32.7% and 90.9%, and vein ultrasonography 52.7% and 97.6%, respectively. Among the 132 patients (37%) with multiorgan ultrasonography negative for PE plus an alternative ultrasonographic diagnosis or plus a negative D-dimer result, no patients received PE as a final diagnosis. CONCLUSIONS Multiorgan ultrasonography is more sensitive than single-organ ultrasonography, increases the accuracy of clinical pretest probability estimation in patients with suspected PE, and may safely reduce the MCTPA burden. TRIAL REGISTRY ClinicalTrials.gov; No.: NCT01635257; URL: www.clinicaltrials.gov.

Accuracy of lung ultrasound for the diagnosis of consolidations when compared to chest computed tomography

OBJECTIVES Despite emerging evidences on the clinical usefulness of lung ultrasound (LUS), international guidelines still do not recommend the use of sonography for the diagnosis of pneumonia. Our study assesses the accuracy of LUS for the diagnosis of lung consolidations when compared to chest computed tomography (CT). METHODS This was a prospective study on an emergency department population complaining of respiratory symptoms of unexplained origin. All patients who had a chest CT scan performed for clinical reasons were consecutively recruited. LUS was targeted to evaluate lung consolidations with the morphologic characteristics of pneumonia, and then compared to CT. RESULTS We analyzed 285 patients. CT was positive for at least one consolidation in 87 patients. LUS was feasible in all patients and in 81 showed at least one consolidation, with a good inter-observer agreement (k = 0.83), sensitivity 82.8% (95% CI 73.2%-90%) and specificity 95.5% (95% CI 91.5%-97.9%). Sensitivity raised to 91.7% (95% CI 61.5%-98.6%) and specificity to 97.4% (95% CI 86.5%-99.6%) in patients complaining of pleuritic chest pain. In a subgroup of 190 patients who underwent also chest radiography (CXR), the sensitivity of LUS (81.4%, 95% CI 70.7%-89.7%) was significantly superior to CXR (64.3%, 95% CI 51.9%-75.4%) (P<.05), whereas specificity remained similar (94.2%, 95% CI 88.4%-97.6% vs. 90%, 95% CI 83.2%-94.7%). CONCLUSIONS LUS represents a reliable diagnostic tool, alternative to CXR, for the bedside diagnosis of lung consolidations in patients with respiratory complains.

Lung Ultrasound Predicts Well Extravascular Lung Water but Is of Limited Usefulness in the Prediction of Wedge Pressure

Background:Pulmonary congestion is indicated at lung ultrasound by detection of B-lines, but correlation of these ultrasound signs with pulmonary artery occlusion pressure (PAOP) and extravascular lung water (EVLW) still remains to be further explored. The aim of the study was to assess whether B-lines, and eventually a combination with left ventricular ejection fraction (LVEF) assessment, are useful to differentiate low/high PAOP and EVLW in critically ill patients. Methods:The authors enrolled 73 patients requiring invasive monitoring from the intensive care unit of four university-affiliated hospitals. Forty-one patients underwent PAOP measurement by pulmonary artery catheterization and 32 patients had EVLW measured by transpulmonary thermodilution method. Lung and cardiac ultrasound examinations focused to the evaluation of B-lines and gross estimation of LVEF were performed. The absence of diffuse B-lines (A-pattern) versus the pattern showing prevalent B-lines (B-pattern) and the combination with normal or impaired LVEF were correlated with cutoff levels of PAOP and EVLW. Results:PAOP of 18 mmHg or less was predicted by the A-pattern with 85.7% sensitivity (95% CI, 70.5 to 94.1%) and 40.0% specificity (CI, 25.4 to 56.4%), whereas EVLW 10 ml/kg or less with 81.0% sensitivity (CI, 62.6 to 91.9%) and 90.9% specificity (CI, 74.2 to 97.7%). The combination of A-pattern with normal LVEF increased sensitivity to 100% (CI, 84.5 to 100%) and specificity to 72.7% (CI, 52.0 to 87.2%) for the prediction of PAOP 18 mmHg or less. Conclusions:B-lines allow good prediction of pulmonary congestion indicated by EVLW, whereas are of limited usefulness for the prediction of hemodynamic congestion indicated by PAOP. Combining B-lines with estimation of LVEF at transthoracic ultrasound may improve the prediction of PAOP.

Usefulness of emergency ultrasound in nontraumatic cardiac arrest

Treatment of nontraumatic cardiac arrest in the hospital setting depends on the recognition of heart rhythm and differential diagnosis of the underlying condition while maintaining a constant oxygenated blood flow by ventilation and chest compression. Diagnostic process relies only on patients history, physical findings, and active electrocardiography. Ultrasound is not currently scheduled in the resuscitation guidelines. Nevertheless, the use of real-time ultrasonography during resuscitation has the potential to improve diagnostic accuracy and allows the physician a greater confidence in deciding aggressive life-saving therapeutic procedures. This article reviews the current opinions and literature about the use of emergency ultrasound during resuscitation of nontraumatic cardiac arrest. Cardiac and lung ultrasound have a great potential in identifying the reversible mechanical causes of pulseless electrical activity or asystole. Brief examination of the heart can even detect a real cardiac standstill regardless of electrical activity displayed on the monitor, which is a crucial prognostic indicator. Moreover, ultrasound can be useful to verify and monitor the tracheal tube placement. Limitation to the use of ultrasound is the need to minimize the no-flow intervals during mechanical cardiopulmonary resuscitation. However, real-time ultrasound can be successfully applied during brief pausing of chest compression and first pulse-check. Finally, lung sonographic examination targeted to the detection of signs of pulmonary congestion has the potential to allow hemodynamic noninvasive monitoring before and after mechanical cardiopulmonary maneuvers.

Lung ultrasound in diagnosing and monitoring pulmonary interstitial fluid

Chronic heart failure is a complex clinical syndrome often characterised by recurrent episodes of acute decompensation. This is acknowledged as a major public health problem, leading to a steadily increasing number of hospitalisations in developed countries. In decompensated heart failure, the redistribution of fluids into the pulmonary vascular bed leads to respiratory failure, a common cause of presentation to the emergency department. The ability to diagnose, quantify and monitor pulmonary congestion is particularly important in managing the disease. Lung ultrasound (US) is a relatively new method that has gained a growing acceptance as a bedside diagnostic tool to assess pulmonary interstitial fluid and alveolar oedema. The latest developments in lung US are not because of technological advance but are based on new applications and discovering the meanings of specific sonographic artefacts designated as B-lines. Real-time sonography of the lung targeted to detection of B-lines allows bedside diagnosis of respiratory failure due to impairment of cardiac function, as well as quantification and monitoring of pulmonary interstitial fluid. Lung US saves time and cost, provides immediate information to the clinician and relies on very easy-toacquire and highly reproducible data.RiassuntoL’insufficienza cardiaca cronica è una complessa sindrome clinica caratterizzata spesso da episodi ricorrenti di scompenso acuto. Tale condizione rappresenta uno dei maggiori problemi di salute pubblica, che porta ad un numero sempre crescente di ospedalizzazione nei paesi più sviluppati. Nella insufficienza cardiaca scompensata, la redistribuzione dei fluidi nel letto vascolare polmonare comporta l’insufficienza respiratoria, una causa comune di presentazione nel Dipartimento di Emergenza. La capacità di diagnosticare, quantificare e monitorare la congestione polmonare è di particolare importanza nel trattamento di questa malattia. L’ecografia polmonare è un metodo relativamente nuovo, oramai sempre più diffusamente riconosciuto come mezzo diagnostico utile per la valutazione dell’edema interstiziale ed alveolare al letto del paziente. Il recente sviluppo dell’ecografia polmonare non è legato allo sviluppo tecnologico, ma è basato sulle nuove applicazioni e sulla scoperta del significato di specifici artefatti ecografici chiamati linee B. L’ecografia polmonare mirata alla identificazione delle linee B permette la diagnosi al letto del paziente in tempo reale dell’insufficienza respiratoria dovuta a scompenso cardiaco, cosÌ come la quantificazione ed il monitoraggio della congestione polmonare. La tecnica ecografica polmonare riduce i tempi ed i costi diagnostici, e si basa su segni semplici da identificare ed altamente riproducibili che forniscono immediate informazioni nella gestione del paziente.

A comparison of different diagnostic tests in the bedside evaluation of pleuritic pain in the ED.

PURPOSES Bedside lung ultrasound (LUS) is useful in detecting radio-occult pleural-pulmonary lesions. The aim of our study is to compare the value of LUS with other conventional routine diagnostic tools in the emergency department (ED) evaluation of patients with pleuritic pain and silent chest radiography (CXR). METHODS Ninety patients consecutively admitted to the ED with pleuritic pain and normal CXR were retrospectively (n = 49) and prospectively (n = 41) studied. All patients were blindly examined by LUS and submitted to clinical examination and blood samples. The ability of blood tests and symptoms to predict any radio-occult pleural-pulmonary condition confirmed by conclusive image techniques and follow-up was evaluated and compared with LUS. RESULTS In 57 cases, the final diagnosis was chest wall pain. The other 33 patients were diagnosed with a pleural-pulmonary condition (22 pneumonia, 2 pleuritis, 7 pulmonary embolism, 1 lung cancer, 1 pneumothorax). Lung ultrasound showed a sensitivity of 96.97% (95% confidence interval [CI], 84.68%-99.46%) and a specificity of 96.49% (95% CI, 88.08%-99.03%) in predicting radio-occult pleural-pulmonary lesions and significantly higher area under the curve (AUC) of receiver operating characteristic analysis (AUC, 0.967; 95% CI, 0.929-1.00) than d-dimer (AUC, 0.815; 95% CI, 0.720-0.911) and white blood cell count (AUC, 0.778; 95% CI, 0.678-0.858). None of the other routine tests considered or a combination between them better predicted the final diagnosis. CONCLUSIONS Chest radiography and blood tests may be inadequate in the diagnostic process of pleuritic pain. In case of silent CXR, LUS is critical for identifying patients with pleural-pulmonary radio-occult conditions at bedside and cannot be safely replaced by other conventional methods.

Clinical application of lung ultrasound in patients with acute dyspnoea: differential diagnosis between cardiogenic and pulmonary causes

This review discusses the usefulness of bedside lung ultrasound in the diagnostic distinction between the various causes of acute dyspnoea in the emergency department, with special attention to the differential diagnosis of pulmonary oedema and exacerbation of chronic obstructive pulmonary disease (COPD). This is made possible by using mid- to low-end scanners and simple acquisition techniques accessible to both radiologists and clinicians. Major advantages include ready availability at the bedside, the absence of ionising radiation, high reproducibility and cost efficiency. The technique is based on the recognition and analysis of sonographic artefacts rather than direct visualisation of the pulmonary structures. These artefacts are caused by the interaction of water-rich structures and air, called comet tails or B-lines. When such artefacts are widely detected on anterolateral transthoracic lung scans, diffuse alveolar-interstitial syndrome can be diagnosed, which is often a sign of acute pulmonary oedema. This condition rules out exacerbation of COPD as the main cause of acute dyspnoea.RiassuntoIn questo lavoro viene discussa l’utilità dell’ecografia polmonare nella diagnosi delle diverse cause di dispnea acuta in emergenza, in particolare focalizzando l’attenzione sulla diagnosi differenziale tra l’edema polmonare e la riacutizzazione della broncopneumopatia cronica ostruttiva (BPCO). Questo è possibile utilizzando anche ecografi di fascia medio-bassa ed avvalendosi di tecniche di facile acquisizione da parte sia dei radiologi che dei clinici. I maggiori vantaggi dell’ecografia includono la sua pronta disponibilità al letto del malato, l’assenza di radiazioni ionizzanti, la riproducibilità ed i costi ridotti. La tecnica è basata sul riconoscimento e l’analisi di alcuni artefatti invece che sulla visualizzazione diretta delle strutture polmonari. Questi artefatti sono causati dalla presenza di strutture ricche di acqua ed aria, e sono chiamati “code di cometa” o linee B. Quando tali artefatti sono diffusamente visualizzati nelle scansioni trans-toraciche antero-laterali, è possibile diagnosticare la sindrome alveolo-interstiziale diffusa, che è spesso un segno di edema polmonare acuto. Questa condizione esclude la riacutizzazione di BPCO quale causa di dispnea acuta.

Effectiveness of chest radiography, lung ultrasound and thoracic computed tomography in the diagnosis of congestive heart failure

Hydrostatic pulmonary edema is as an abnormal increase in extravascular water secondary to elevated pressure in the pulmonary circulation, due to congestive heart failure or intravascular volume overload. Diagnosis of hydrostatic pulmonary edema is usually based on clinical signs associated to conventional radiography findings. Interpretation of radiologic signs of cardiogenic pulmonary edema are often questionable and subject. For a bedside prompt evaluation, lung ultrasound (LUS) may assess pulmonary congestion through the evaluation of vertical reverberation artifacts, known as B-lines. These artifacts are related to multiple minimal acoustic interfaces between small water-rich structures and alveolar air, as it happens in case of thickened interlobular septa due to increase of extravascular lung water. The number, diffusion and intensity of B lines correlates with both the radiologic and invasive estimate of extravascular lung water. The integration of conventional chest radiograph with LUS can be very helpful to obtain the correct diagnosis. Computed tomography (CT) is of limited use in the work up of cardiogenic pulmonary edema, due to its high cost, little use in the emergencies and radiation exposure. However, a deep knowledge of CT signs of pulmonary edema is crucial when other similar pulmonary conditions may occasionally be in the differential diagnosis.