POCUS (Point of Care Ultrasound) refers to ultrasound performed by clinicians as part of their initial patient evaluation, often with the aim of answering a specific question as opposed to being a comprehensive assessment. Such ultrasound is noninvasive, involves no radiation and can be rapidly performed at the bedside. It is also widely practiced in emergency and intensive care medicine leading to earlier and more accurate diagnoses for a wide range of presentations such as shock, renal failure and dyspnoea. POCUS has evolved from cardiological or radiological studies, reduced in complexity and scoped for clinician use. Lung ultrasound (LUS) has been largely developed by acute care clinicians and is a more recent addition to POCUS. Procedural LUS is widely recommended to improve the safety profile of pleural catheter placement (referring to BTS guidelines) but in the UK diagnostic LUS is not widely practiced despite good evidence and guideline support for its use. In this article we briefly review and describe the role of diagnostic LUS as applied to acute medicine. Potential advantages of LUS include a decreased time to diagnosis, improved diagnostic accuracy, a reduction in radiation exposure and unnecessary expensive tests. Studies have shown that at least one diagnosis was missed in around a fifth of patients with acute respiratory symptoms, resulting in increased length of stay and mortality in a third of patients.

[download-attachments container="div" style="list" display_icon="1" display_count="1" display__size="0"]

References

1. Mayo PH, Beaulieu Y, Doelken P et al. American College of Chest Physicians/La Societe de Reanimation de Langue Francaise statement on competence in critical care ultrasonography. Chest. 2009; 135(4):1050–60.
2. Cortellaro F, Ferrari L, Molteni F et al. Accuracy of point of care ultrasound to identify the source of infection in septic patients: a prospective study. Intern Emerg Med. 2017 Apr; 12(3):371-378.
3. Joaquín Valle Alonso,, John Turpie, Islam Farhad et al. Protocols for Point of Care (POCUS) in a patient with sepsis; An Algorithmic Approach. Bull Emerg Trauma. 2019 Jan; 7(1): 67–71.
4. Piotr Ponikowski Adriaan A Voors Stefan D Anker et al. 2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC) Developed with the special contribution of the Heart Failure Association (HFA) of the ESC. European Heart Journal, Volume 37, Issue 27, 14 July 2016, Pages 2129–2200.
5. Ray P, Birolleau S, Lefort Y, et al. Acute respiratory failure in the elderly: etiology, emergency diagnosis and prognosis. Crit Care 2006; 10: R82.
6. Laursen CB, Sloth E, Lambrechtsen J, et al. Focused sonography of the heart, lungs, and deep veins identifies missed life-threatening conditions in admitted patients with acute respiratory symptoms. Chest 2013;144:1868–75.
7. Laursen CB, Sloth E, Lassen AT, et al. Point-of-care ultrasonography in patients admitted with respiratory symptoms: a single-blind, randomised controlled trial. Lancet Respir Med 2014;2:638–46.
8. Volpicelli, Giovanni; Silva et al. Real-time lung ultrasound for the diagnosis of alveolar consolidation and interstitial syndrome in the emergency department. Euro J Emerg Med 2010;17:63-72.
9. Lichtenstein D and Gilbert A. Relevance of Lung Ultrasound in the Diagnosis of Acute Respiratory Failure. The Blue Protocol. Chest 2008;134:117-125.
10. Bekgoz B, Kilicaslan I, Bildik F. BLUE protocol ultrasonograghy in Emergency Department patients presenting with acute dyspnea. The American Journal of Emergency Medicine. Available online Feb 2019. doi: 10.1016/j.ajem.2019.02.028.
11. Miller A. Practical approach to lung ultrasound. BJA Education, Vol 16 (2); Feb 2016: 39-45.
12. Rudas M, Orde S, Nalos M. Bedside lung ultrasound in the critically ill. Crit Care Resusc 2017; 19: 327-336.
13. Lee F, Jenssen C, Dietrich C. A common misunderstanding in lung ultrasound: The comet tail artefact. Medical Ultrasonography. 2018. 20. 10.11152/mu-1573.
14. Copetti R, Soldati G, Copetti P. Chest sonography: a useful tool to differentiate acute cardiogenic pulmonary oedema from acute respiratory distress syndrome. Cardiovascular ultrasound 2008;6:16 doi:10.1186/1474-7120-6-16.
15. Lichtenstein D, Mezière G. A lung ultrasound sign allowing bedside distinction between pulmonary edema and COPD: the comet-tail artifact. Intensive Care Med 1998; 24: 1331-4.
16. Lichtenstein D, Menu Y. A bedside ultrasound sign ruling out pneumothorax in the critically ill: lung sliding. Chest 1995, 108: 1345–1348. 10.1378/chest.108.5.1345
17. Lichtenstein D. Lung ultrasound in the critically ill. Annals of Intensive Care 2014; 4:1. doi:10.1186/2110-5820-4-1.
18. Lichtenstein D, Mezière G, Biderman P et al. The lung point: an ultrasound sign specific to pneumothorax. Intensive Care Med 2000, 26: 1434–1440. 10.1007/s001340000627.
19. Henning D, Kearney K, Hall K et al. Identification and Riskstratification of Hypotensive Patients With Cardiogenic Etiologies. Acad Emerg Med 2017; 24:S63.
20. Pagano A, Numis F, Visone G et al. Lung ultrasound for diagnosis of pneumonia in emergency department. Int Emerg Med 2015;10:851-854.
21. Reissig A, Copetti R, Mathis G, et al. Lung ultrasound in the diagnosis and follow-up of community-acquired pneumonia. A prospective, multicenter, diagnostic accuracy study. Chest 2012; 142:965–972.
22. Ticinesi A, Laurenti F, Nouvenne A et al. Lung Ultrasound and chest x-ray for detecting pneumonia in an acute geriatric ward. Medicine; July 2016: 95 (27): e4153.
23. Llamas-Álvarez AM, Tenza-Lozano EM, Latour-Pérez J, Accuracy of lung ultrasound in the diagnosis of pneumonia in adults: systematic review and meta-analysis, Chest 2017; 151 (2): 374-382. doi: 10.1016/j.chest.2016.10.039.
24. McGivery K, Atkinson P, Lewis D et al. Emergency department ultrasound for the detection of B-lines in the early diagnosis of acute decompensated heart failure: a systematic review and metaanalysis. CJEM 2018; 20(3): 343-352.
25. Maw A,å Hassanin A, Ho M et al. Diagnostic accuracy of pointof-care lung ultrasonography and chest radiography in adults with symptoms suggestive of acute decompensated heart failure. A systematic review and meta-analysis. JAMA Netw Open. 2019; 2(3): e190703. doi:10.1001/jamanetworkopen.2019.0703.
26. Pivetta E, Goffi A, Nazerian P et al. Lung ultrasound integrated with clinical assessment for the diagnosis of acute decompensated heart failure in the emergency department: a randomised controlled trial. Eur Jour Heart Failure. Jan 2019. doi:10.1002/ejhf.1379.
27. Russell F & Ehrman R. A modified lung and cardiac ultrasound protocol saves time and rules in the diagnosis of acute heart failure. June 2017 52(6): 839-845.
28. Chiem A, Chan C, Ander D et al. Comparison of expert and novice sonographers’ performance in focused lung ultrasonography in dyspnea (FLUID) to diagnose patients with acute heart failure syndrome. Acad Emerg Med 2015; 22: 564-73.
29. Lichtenstein D, Goldstein I, Mourgeon E et al. Comparative diagnostic performances of auscultation, chest radiography, and lung ultrasonography in acute respiratory distress syndrome. Anesthesiology Jan 2004; 100(1): 9-15.
30. Blackmore C, Black W, Dallas et al. Pleural fluid volume estimation: a chest radiograph prediction rule. Acad Radiol Feb 1996; 3(2): 103-9.
31. Eibenberger KL, Dock WI, Ammann ME, et al. Quantification of Pleural Effusions: Sonography versus Radiography. Radiology 1994; 191: 681-4.
32. Barnes TW, Morgenthaler TI, Olson EJ, et al. Sonographically guided thoracentesis and rate of pneumothorax. J Clin Ultrasound 2005; 33: 442-6.
33. Mayo PH, Goltz HR, Tafreshi M, Doelken P. Safety of ultrasound guided thoracentesis in patients receiving mechanical ventilation. Chest 2004; 125: 1059-62.
34. Jones PW, Moyers JP, Rogers JT, et al. Ultrasound-guided thoracentesis: is it a safer method? Chest 2003; 123: 418-23.
35. Kusminsky RE. Complications of central venous catheterization. J Am Coll Surg. 2007;204:681–96.
36. Sznajder JI, Zveibil FR, Bitterman H et al. Central vein catheterization. Failure and complication rates by three percutaneous approaches. Arch Intern Med. 1986;146:259–61.
37. Bhutta ST, Culp WC. Evaluation and management of central venous access complications. Tech Vasc Interv Radiol. 2011;14:217– 24.
38. Nakitende D, Gottilieb M, Ruskis J et al. Ultrasound for confirmation of thoracostomy tube placement by emergency medicine residents. Trauma 2017; 19(1): 35-38.
39. Baldt M, Bankier A, Germann P, et al. Complications after emergency tube thoracostomy: assessment with CT. Radiology 1995; 195: 539–543.
40. Chan L, Reilly K, Henderson C, et al. Complication rates of tube thoracostomy. Am J Emerg Med 1997; 15: 368–370.
41. Lim K, Tai S, Chan C, et al. Diagnosis of malpositioned chest tubes after emergency tube thoracostomy. Clin Imaging 2005; 29: 401–405.