Thoracic ultrasonography: A new method for the work-up of patients with dyspnea

Abstract

Objective: Differential diagnosis of dyspnea is vital for the management of respiratory failure, where routine parameters can now be integrated with thoracic ultrasound data. The objective of this study was to evaluate the validity and accuracy of this approach in a department of internal medicine. Materials and methods: We enrolled 152 patients consecutively hospitalized with a diagnosis of dyspnea. After clinical evaluation, chest radiography, biochemical assays (NT-proBNP), and emergency treatment, patients underwent ultrasound examination of the lungs. Results were considered positive if the total number of lines B was higher than 8. The ultrasound examination and NT-proBNP assay were repeated after 48 h. The gold standard was the clinical diagnosis of heart failure made by medical experts in accordance with AHA guidelines. Results: The group of patients with positive ultrasound findings had a higher frequency of heart failure diagnoses (X 2 92.5, p < 0.005) and significantly higher values of NT-proBNP (10,384 ng/l vs 3889 ng/l, p < 0.05). Moreover, the decrease in the number of B lines at 48 h was significantly greater (p < 0.005) among patients treated for heart failure. There were no significant changes in the values of NT-proBNP (p Z 0.37). Discussion: In conclusion we have shown that even in a department of internal medicine, lung ultrasonography is a useful tool for diagnosing respiratory insufficiency and monitoring its response to therapy.Sommario La diagnosi differenziale di dispnea è fondamentale per la gestione dell'insufficienza respiratoria in cui, ai parametri routinari, può essere ora affiancata l'ecografia toracica. L'obiettivo di questo studio è stato valutare la validità e l'accuratezza di questa metodica anche in un reparto di medicina interna. dell'NT-proBNP sono stati ripetuti dopo 48 ore. Il gold standard di riferimento è stato la diagnosi clinica di scompenso cardiaco fatta da medici esperti secondo le linee guida dell'AHA. Risultati: Il gruppo di pazienti che mostrava un esame ecografico positivo riceveva in percentuale maggiore la diagnosi finale di insufficienza cardiaca (X 2 92.5; p < 0.005) e valori significativamente più elevati di NT-proBNP (10,384 ng/l vs 3889 ng/l; p < 0.05).Inoltre la diminuzione delle linee B a 48 ore era significativamente maggiore (p < 0.005) nel gruppo di pazienti trattati per scompenso cardiaco mentre non vi erano cambiamenti significativi nei valori di NT-proBNP (p Z 0.37). Discussione: In conclusione abbiamo dimostrato che anche in un reparto di medicina interna l'ecografia polmonare è uno strumento diagnostico utile per le gestione dell'insufficienza respiratoria e il suo monitoraggio durante la terapia. ª

Sensitivity and specificity of ultrasound for the diagnosis of acute pulmonary edema: a systematic review and meta-analysis

“…After removing the duplicate studies and the studies that did not fulfill the inclusion criteria, 8 studies were included in the meta-analysis (1301 patients; Table I) [10][11][12][13][14][15][16][17]. Two studies were performed in the ICU, three studies in the ED, two studies in the ward and one study in a pre-hospital setting and ED.…”

“…Two studies diagnosed the PE by detecting B-line in anterior and lateral chest and three or more B-lines in at least two zones on each hemithorax [12,13]. Another two studies followed comet-score scanning protocol for diagnosis of PE [11,17]. The QUADAS-2 quality assessment revealed that quality of the included studies was from moderate to high (Table II).…”

“…The protocol of Lichtenstein et al involved scanning of comet-tail artifact produced from pleural line [12]. Comet score scanning protocol as described by Picano et al [19] was applied by Vitturi et al [17] and Gargani et al [11] in determination of extravascular lung water; the test was considered as abnormal when the number of B-lines was greater than five [11] or eight [17]. Subgroup analysis was not carried out in these studies and this contributed to the heterogeneity of our data.…”

“…The sensitivity of chest radiography, BNP, and NT proBNP tests in the diagnosis of acute dyspnea ranged from 56%-93%, 86%-99% and 92%-97%, respectively, while the specificity ranged from 51%-98%, 74%-99% and 44%-93%, respectively [11,[15][16][17][20][21][22][23][24][25]. Although high sensitivity and specificity of the mentioned diagnostic methods were reported, real-time valuation of the outcome is almost impossible and the assessments are not available in the pre-hospital setting.…”

Serial lung and IVC ultrasound in the assessment of congestive heart failure

“…Both lung [18, 19] and vascular ultrasound [20–22] have been shown to be helpful in the assessment of undifferentiated dyspnea and in the diagnosis of heart failure. It is not clear how POCUS findings change with treatment.…”