Using Ultrasound to Predict the Results of Draining Pleural Effusions

Pleural effusion is an extremely common problem with multiple causes; its subsequent investigation with thoracocentesis and treatment with drainage represent two of the most frequently performed diagnostic and therapeutic medical procedures. The role of thoracic ultrasonography in the management of pleural effusion is a modern and rapidly expanding one, having become effectively mandatory and part of the "gold standard" over the past decade due to its diagnostic and patient safety benefits. By contrast, the measurement of intra-pleural pressure using sequential manometry has failed to convincingly demonstrate its clinical value beyond physiological studies despite its availability for over a century. Previous work has shown a potential role for pleural manometry in predicting the presence of un-expandable lung and success of talc pleurodesis but these studies have not been replicated or clinically validated. We intend to combine the old and new in an observational study comparing findings on thoracic ultrasonography and pleural manometry during thoracocentesis with patient-reported symptoms and the key clinical outcomes of presence of un-expandable lung and success of talc pleurodesis. The investigators hypothesise that the previously described variations in pleural elastance can be correlated with appearances and anatomical changes visualised on thoracic ultrasonography; and in combination can be reliably utilised to predict clinical outcome. The study may allow the proposal of a treatment algorithm that allows patients with pleural effusion to be managed in a more expeditious and efficient manner.