Making Waves: Lung Ultrasound and Physiotherapy Practice

Physiotherapists who work in respiratory care spend a great deal of time developing expertise in the use of a range of assessment tools including: observation, palpation, auscultation and percussion. Further specialist skills are needed for the interpretation of arterial blood gas (ABG); chest radiographs (CXR) and computed tomography (CT), in order to ensure the most accurate diagnosis can be made and best treatment delivered. However, many physiotherapists still rely on other professionals for some specialist aspects of the patient assessment (e.g. CXR or CT) which necessitates convincing others to perform such tests and may result in delayed treatment. The boundaries between professional roles are blurring, for example a competent physiotherapist can take ABG and the results used to inform clinical reasoning right at the point of care. The earliest evidence I can find of a respiratory physiotherapist using an ultrasound scan to inform practice was a paper published in 1997 by Blaney and Sawyer [1]. In this paper the physiotherapist aimed to compare the effects of three different breathing techniques on diaphragmatic excursion, after upper abdominal surgery. While, back in 1997, the scan of the diaphragm was done by a sonographer, the question is now posed, have we reached the time when lung diagnostic imaging has come into the crosshairs of physiotherapists and should physiotherapists learn how to image? Professor Daniel Lichtenstein is one of the pioneers of point-of-care ultrasound (POCUS) in critical care and he strongly advocates the use of diagnostic lung ultrasound to inform clinical reasoning. In his book, “Lung Ultrasound in the Critically Ill: The BLUE Protocol” [2], when discussing physiotherapy contribution to patient care in ICU he argues that physiotherapists should acquire ultrasound imaging skills and that ‘ultrasound should change many aspects of the [physiotherapy] protocols, since the result can be seen on site.” (p293). Lung ultrasound (LUS), also known as thoracic ultrasound, uses diagnostic ultrasound to image the pleura, lung parenchyma and diaphragm. Two narrative reviews around the use of LUS by physiotherapists have previously been published. Leech et al. [3] focused on the diagnostic performance of LUS when compared to auscultation and CXR and found that LUS increased diagnostic accuracy when identifying acute pulmonary pathology, but these authors reported a lack of training standards for physiotherapists. Le Neindre et al. [4] focused on the basic aspects of LUS, its semiology and how to apply LUS in practice. They report that LUS performs better than CXR and auscultation and should be considered as an outcome measure and used to inform clinical decision making. A number of recent systematic reviews have advocated the use of LUS to assess pathologies such as pneumonia [5], pleural effusion [6] and diaphragmatic dysfunction [7]. The potential benefits of LUS make it a powerful tool to assist clinicians to differentially diagnose many lung pathologies and conditions. Historically physiotherapists have relied on radiographers to provide imaging with or without an accompanied report. However, the findings from a CXR or CT image become less reliable as time passes which may result in physiotherapists being vulnerable to over treating conditions that have