Ultrasonographic quantification of pleural effusion: comparison of four formulae

Abstract

PurposeThe purpose of this study was to evaluate the correlations of ultrasonographically estimated volumes of pleural fluid with the actual effusion volume in order to determine the most reliable formula.MethodsIn 32 consecutive patients with clinically diagnosed pleural effusion, an ultrasound estimation was made of the volume of effusion using four different formulae, including two in the erect position and two in the supine position. Closed-tube thoracostomy drainage using a 28-Fr chest tube was performed. The total drainage was calculated after confirmation of full lung re-expansion and complete drainage by plain chest radiographs and ultrasound. The ultrasonographically estimated volume was compared to the actual total volume drained as the gold standard.ResultsThere were 14 female and 18 male subjects. The mean age of all subjects was 41.56±18.34 years. Fifty percent of the effusions were in the left hemithorax. Metastatic disease accounted for the plurality of effusions (31.2%). The mean total volume drained for all the subjects was 2,770±1,841 mL. The ultrasonographically estimated volumes for the erect 1, erect 2, supine 1, and supine 2 formulae were 1,816±753 mL, 1,520±690 mL, 2,491±1,855 mL, and 1,393±787 mL, respectively. The Pearson correlation coefficients (r) for the estimate of each formula were 0.75, 0.81, 0.62, and 0.63, respectively.ConclusionAlthough both erect formulae showed similar correlations, the erect 2 formula (Goecke 2) was most closely correlated with the actual volume drained.

<p>Global Ultrasound Check for the Critically lll (GUCCI)—a new systematized protocol unifying point-of-care ultrasound in critically ill patients based on clinical presentation</p>

“…Pleural effusion is characterized by the presence of an anechoic space between the visceral and parietal pleura. However, quantifying the volume of pleural effusion still remains a challenge although there are multiple methods to do so 31. We generally estimate its volume (in milliliters) in the supine patient with the probe positioned transversally in the posterior axillary line at the pulmonary base.…”

Better With Ultrasound

“…[18][19][20] For pleural effusion, LUS is extraordinarily sensitive and can detect fluid volumes as low as 5 to 20 mL, whereas standard upright chest radiograph typically cannot detect volumes < 150 mL. 21 Characterization of pleural fluid, with identification of septations, complexity, and loculations, is superior to other imaging modalities. Ultrasound can be used for procedural guidance, such as thoracentesis or thoracostomy tube placement.…”

“…The ability to visualize the vertebral bodies deep to the pleural effusion, a phenomenon known as the spine sign, which takes advantage of the acoustic enhancement afforded by the pleural fluid, can be helpful in confirming the diagnosis. 34 The volume of the effusion can be estimated either qualitatively or quantitatively using one of several formulae that have been published, 21 and the complexity of the effusion (whether simple or loculated) can also be of interest. 22,35 Examination of the PLAPS point also can demonstrate the presence of consolidated lung tissue, as seen in Figures 4C and 4D.…”

Utilidad y fiabilidad de la ecografía clínica en Medicina Familiar: ecocardioscopia y ecografía pulmonar

“…Se visualizará como la presencia de líquido entre la pleura parietal y la visceral; anecogénico en los trasudados, pudiendo tener cualquier aspecto en los exudados (desde anecogénico hasta derrames pleurales complejos, tabicados y con contenido ecogénico) 46 . Se puede estimar la cantidad de derrame 47 , así como anticipar la complejidad de la toracocentesis (permite prever la necesidad de agujas de mayor calibre en derrames complejos, la dificultad de drenaje en los tabicados o determinar el mejor abordaje). El uso de la ecografía durante la toracocentesis permite guiar la aguja, mejorando la precisión y minimizando el riesgo de complicaciones, por lo que es altamente recomendable 48 .…”