Guideline sources The following summarized guidelines for the evaluation and management of pleural effusion are prepared by our editorial team based on guidelines from the American Thoracic Society (ATS 2018) and the British Thoracic Society (BTS 2017; 2010). 1 2 3 4 5 5 5 6 6 Definition Pleural effusion is a disease characterized by pathologic accumulation of fluid in the pleural space. 5 Epidemiology Common causes of pleural effusions include congestive HF, pneumonia, malignancy, and PE. 5 Pathophysiology The incidence of pleural effusion in the United States is estimated at 400 cases per 100,000 person-years. 6 Disease course Accumulation of fluid in the pleural space with resultant pleural irritation and compression atelectasis results in clinical manifestations of dyspnea, pleuritic pain, and dry cough. 5 i d i k f https://web.pathway.md/diseases/recYiMDZdt1hT5LLP 1/6 6/29/23, 11:15 PM Pleural effusion Pathway Prognosis and risk of recurrence In hospitalized patients, pleural effusion is associated with 30-day and 1-year mortality of 15% and 32%, respectively. 6 Pathway Pleural effusion Investigation Guidelines 1. Diagnostic investigations Clinical history: elicit an accurate drug history as part of the initial clinical assessment of patients with pleural effusion. E Blood cultures: obtain blood cultures for aerobic and anaerobic bacteria in all patients with suspected pleural infection. B Chest radiographs: obtain posteroanterior CXRs as part of the assessment of suspected pleural effusion. E Bedside ultrasound: ultrasound detects pleural fluid septations with greater sensitivity than CT. B Chest CT: Obtain a CT scan of the chest in all patients with undiagnosed exudative pleural effusions. CT can assist in distinguishing malignant from benign pleural thickening. B Perform CT scan of the chest with the administration of intravenous contrast, and before complete drainage of pleural fluid. B 2. Diagnostic procedures Diagnostic thoracentesis: perform a diagnostic thoracentesis to obtain a diagnostic pleural fluid sample, using a fine-bore (21G) needle and a 50 mL syringe. E Show 3 more Pleural fluid analysis: use Light's criteria to distinguish between a pleural fluid exudate and transudate. B Show 3 more Pleural fluid cytology: Malignant effusions can be diagnosed by pleural fluid cytology in about 60% of cases. B The yield from sending more than two specimens (taken on different occasions) is very low and should be avoided. B https://web.pathway.md/diseases/recYiMDZdt1hT5LLP 2/6 6/29/23, 11:15 PM Pleural effusion Pathway Pleural fluid immunohistochemistry: obtain immunocytochemistry to differentiate between malignant cell types and assist in guiding oncological therapy. B Pleural fluid and serum tumour markers: evidence suggests that pleural fluid and serum tumour markers do not currently have a role in the routine investigation of pleural effusions. B Percutaneous pleural biopsy: perform an image-guided cutting needle percutaneous pleural biopsy in patiens with an undiagnosed effusion where malignancy is suspected, and areas of pleural nodularity are demonstrated on contrast-enhanced CT. A Thoracoscopic biopsy: perform thoracoscopy in patients with an exudative pleural effusion in whom malignancy is suspected, when diagnostic pleural aspiration results are inconclusive. B Diagnostic bronchoscopy: Avoid routine diagnostic bronchoscopy in the evaluation of undiagnosed pleural effusion. D Consider bronchoscopy if there is hemoptysis or clinical or radiographic features suggestive of bronchial obstruction. C 3. Medical management Antibiotic therapy: administer antibiotics in all patients with suspected pleural infection; antibiotics should be targeted to treat the bacterial profile of pleural infection, and based on local antibiotic policies and resistance patterns. B Oxygen saturation targets: target an oxygen saturation of 94-98% in patients with pleural effusions, or 88-92% if the patient is at risk of hypercapnic respiratory failure. B 4. Therapeutic procedures Chest tube drainage: perform chest tube drainage promptly in patients with pleural effusions in whom frankly purulent or cloudy pleural fluid is obtained upon thoracentesis. B Show 4 more 5. Specific circumstances Patients with malignant pleural effusion: consider obtaining an ultrasound to guide pleural interventions in patients with known or suspected malignant pleural effusion. C Show 6 more Patients with chylothorax: obtain pleural fluid triglyceride and cholesterol levels in patients with suspected chylothorax or pseudochylothorax, and test pleural fluid for cholesterol crystals and chylomicrons. B Patients with suspected pleural tuberculosis: thoracoscopic pleural biopsies are the test most likely to yield positive mycobacterial culture (and therefore drug sensitivity) results. B Show 2 more Patients with suspected RA-related effusions: most chronic pleural effusions secondary to rheumatoid arthritis have a very low glucose level of < 1.6 mmol/L (29 mg/dL). B https://web.pathway.md/diseases/recYiMDZdt1hT5LLP 3/6 6/29/23, 11:15 PM Pleural effusion Pathway Patients with suspected SLE-related effusions: avoid the routine measurement of pleural fluid antinuclear antibodies, as it reflects the serum level and is therefore usually unhelpful. D Clinical findings Symptoms Past medical history Dry cough HF Exercise intolerance Injury Feeling of chest heaviness or tightness Kidney failure PE Feeling sick Imaging findings Infection Pain Atelectasis Shortness of breath Blunting of the costophrenic angle Shortness of breath when lying down Hypoechoic thoracic collection Sinusoid sign Respiratory exam Spine sign Absence of breath sounds Asymmetric lung expansion Asymmetric tactile fremitus Auscultatory dullness to percussion Dullness to percussion Likelihood Ratios Pertinent positives The following findings increase the probability of pleural effusion in adults. 6 8 Finding LR+ Value Presence of auscultatory dullness to percussion 95 Presence of blunting of the costophrenic angle 37 Presence of hypoechoic thoracic collection 15.6 Absence of breath sounds 8.8 Show 3 more Pertinent positives The following findings increase the probability of an exudative effusion in adults with a pleural effusion. 7 Finding LR+ Value Increased pleural fluid LDH (> 200 u/L) 18 (6.8-46) Increased pleural cholesterol to serum cholesterol ratio (> 0.3) 14 (5.5-38) https://web.pathway.md/diseases/recYiMDZdt1hT5LLP 4/6 6/29/23, 11:15 PM Pleural effusion Pathway Increased pleural LDH to serum LDH ratio (> 0.6) Increased pleural fluid cholesterol (> 55 mg/dL) 9.2 (5.9-14) 7.1-250 Show 5 more Pertinent negatives The following findings decrease the probability of pleural effusion in adults. 6 8 Finding LR- Value Absence of auscultatory dullness to percussion 0.05 Presence of breath sounds 0.1 Absence of hypoechoic thoracic collection 0.1 Absence of dullness to percussion 0.2 Show 3 more Pertinent negatives The following findings decrease the probability of an exudative effusion in adults with a pleural effusion. 7 Finding LR- Value Negative light's criteria (< 1) 0.04 (0.02-0.11) serum-pleural albumin gradient not decreased ( 1.2 mg/dL) 0.06-0.32 pleural fluid cholesterol not increased ( 55 mg/dL) 0.07-0.16 pleural cholesterol to serum cholesterol ratio not increased ( 0.3) 0.08 (0.05-0.12) Show 5 more References 1. Davies HE, Davies RJ, Davies CW et al. Management of pleural infection in adults: British Thoracic Society Pleural Disease Guideline 2010. Thorax. 2010 Aug;65 Suppl 2:ii41 53. Open 2. Hooper C, Lee YC, Maskell N et al. Investigation of a unilateral pleural effusion in adults: British Thoracic Society Pleural Disease Guideline 2010. Thorax. 2010 Aug;65 Suppl 2:ii4 17. Open 3. Feller-Kopman DJ, Reddy CB, DeCamp MM et al. Management of Malignant Pleural Effusions. An Official ATS/STS/STR Clinical Practice Guideline. Am J Respir Crit Care Med. 2018 Oct 1;198 7 839 849. Open 4. O'Driscoll BR, Howard LS, Earis J et al. BTS guideline for oxygen use in adults in healthcare and emergency settings. Thorax. 2017 Jun;72 Suppl 1):ii1-ii90. Open 5. Jany B, Welte T. Pleural Effusion in Adults-Etiology, Diagnosis, and Treatment. Dtsch Arztebl Int. 2019 May 24;116 21 377 386. Open 6. Kookoolis AS, Puchalski JT, Murphy TE et al. Mortality of Hospitalized Patients with Pleural Effusions. J Pulm Respir Med. 2014 Jun;4 3 184. Open https://web.pathway.md/diseases/recYiMDZdt1hT5LLP 5/6 6/29/23, 11:15 PM Pleural effusion Pathway 7. Enrique Diaz-Guzman and Marie M. Budev. Accuracy of the physical examination in evaluating pleural effusion. Cleveland Clinic Journal of Medicine April 2008, 75 4 297 303;. Open 8. Wilcox ME, Chong CA, Stanbrook MB et al. Does this patient have an exudative pleural effusion? The Rational Clinical Examination systematic review. JAMA. 2014 Jun 18;311 23 2422 31. Open 9. Kataoka H, Takada S. The role of thoracic ultrasonography for evaluation of patients with decompensated chronic heart failure. J Am Coll Cardiol. 2000 May;35 6 1638 46. Open 10. Maskell N, British Thoracic Society Pleural Disease Guideline Group. British Thoracic Society Pleural Disease Guidelines 2010 update. Thorax. 2010 Aug;65 8 667 9. Open 11. Bibby AC, Dorn P, Psallidas I et al. ERS/EACTS statement on the management of malignant pleural effusions. Eur Respir J. 2018 Jul 27;52 1 . pii: 1800349. Open 12. Deirdre B Fitzgerald, Grant W Waterer, Charley Budgeon et al. Steroid Therapy and Outcome of Parapneumonic Pleural Effusions STOPPE A Pilot Randomized Clinical Trial. Am J Respir Crit Care Med. 2022 May 1;205 9 1093 1101. Open https://web.pathway.md/diseases/recYiMDZdt1hT5LLP 6/6