1. Correct Answer: B. Give IV furosemide and order echocardiogram

Rationale: Sonographic evidence of anechoic simple bilateral pleural effusions with diffuse bilateral B lines is suggestive of hydrostatic pulmonary edema (e.g., from congestive heart failure or volume overload). Homogeneously anechoic simple pleural effusions are suggestive of a transudative pleural effusion. If there is a strong suspicion of heart failure as a cause of the effusion and no competing reason for emergent thoracentesis (such as clinically suspected infection), then a trial of medical therapy for heart failure can be prescribed prior to consideration of thoracentesis. Pulmonary embolism and pneumonia are not suggested by the ultrasound imaging.

1. Light R. Clinical practice pleural effusion. N Engl J Med. 2002 Jun;346(25):1971-1977.

2. Correct Answer: B. Hemothorax

Rationale: Pleural effusions that are diffusely echogenic are usually due to debris, which may be RBCs, WBCs, or even protein clumps. Most commonly, these are exudative effusions, such as hemothorax or empyema. It is difficult to differentiate hemothorax from empyema based on sonographic images alone, but the clinical history of recent trauma and rib fractures suggests hemothorax is most likely. It is important to note that even a small volume of blood within a transudative effusion can cause this appearance, as well as setting the 2D gain too high while obtaining images. Evaluation of the pleura would help identify pneumothorax, which is not apparent here. Fat embolism is an important cause of respiratory failure after orthopedic trauma or surgery, but the hemothorax is the most likely cause in this case.

1. Ferreira AC, Filho FM, Braga T, Fanstone GD, Charbel I, Chodraui B. Radiologia Brasileira. Radiol Bras. 2006;39(2):1-9. doi:10.1590/S0100-39842006000200014.

2. Soni NJ, Franco R, Velez MI, et al. Ultrasound in the diagnosis and management of pleural effusions. J Hosp Med. 2015 Dec;10(12):811-816. doi:10.1002/jhm.2434.

3. Correct Answer: A. Chest tube insertion, with consideration for VATS (video-assisted thoracoscopic surgery)

Rationale: Figure 55.3 shows a multiloculated effusion with septations. Fibrin strands and septae are commonly seen in all exudates, including empyema, hemothorax, uremic and malignant pleural effusions. However, the clinical picture of sepsis is strongly suggestive of empyema, which requires drainage. A diagnostic thoracentesis is unnecessary because of the high suspicion for empyema, and it will only delay treatment. A multiloculated effusion with septation is a late stage of parapneumonic effusion, and it requires chest tube insertion with consideration for VATS. Intrapleural tissue plasminogen activator (tPA) and DNAse may facilitate drainage if it is inadequate. Common indications for VATS drainage include multiloculated empyema, empyema refractory to tube thoracostomy, and the presence of a pleural “rind.” Increasing antibiotic coverage may be indicated if a resistant organism is suspected, but evacuation of the infected fluid is the preferred next step in management. CT may help classify additional lesions or evaluate response to drainage, but the ultrasound image is adequate to initiate treatment immediately with thoracostomy.

1. Koppurapu V, Meena N. A review of the management of complex parapneumonic effusion in adults. J Thorac Dis. 2017;9(7):2135-2141. doi:10.21037/jtd.2017.06.21.

2. Yang PC, Luh KT, Chang DB, Wu HD, Yu CJ, Kuo SH. Value of sonography in determining the nature of pleural effusion: analysis of 320 cases. Am J Roentgenol. 1992;159(1):29-33. doi:10.2214/ajr.159.1.1609716.

4. Correct Answer: D. Malignant pleural effusion

Rationale: Sonographic evidence of a pleural nodule is a specific finding in patients with malignant effusion. In a paper by Gorg, et al., 210 patients with exudative pleural effusions were studied by ultrasound for sonographic signs of pleural carcinomatosis. Images were evaluated for echoes within the fluid, septations, sheet-like or nodular pleural masses, and associated lesions of the lung. The study concluded that sonographic findings of echogenic or septated fluid were not specific for malignancy. Only the evidence of pleural masses was characteristic of malignant effusion. CHF is an important cause of pleural effusion, but the visualized nodule is more suggestive of malignancy. Similarly, TB may cause pleural effusion, but is not the most likely cause in this case. Empyema is less likely given the indolent presentation and anechoic appearance of the fluid, but remains a possibility as well.

1. Görg C, Restrepo I, Schwerk WB. Sonography of malignant pleural effusion. Eur Radiol. 1997;7(8):1195-1198. doi:10.1007/s003300050273.

2. Yang PC, Luh KT, Chang DB, Wu HD, Yu CJ, Kuo SH. Value of sonography in determining the nature of pleural effusion: Analysis of 320 cases. Am J Roentgenol. 1992;159(1):29-33. doi:10.2214/ajr.159.1.1609716.

5. Correct Answer: B. There is a right pleural effusion.

Rationale/Critique: Figure 55.5 is a subcostal four-chamber view of the heart, with the liver at the top of the image, adjacent to the RV (see also Figure 55.15). Deep to the heart on the right side of the image is the left pleura. The right pleural space is present on the left side of the image, with a large anechoic region, representing a pleural effusion. There is no evidence for pericardial effusion, which would typically be apparent between the liver and the RV, at the top of the image.

6. Correct Answer: B. Perform diagnostic thoracentesis, send adenosine deaminase (ADA)

Rationale: This is a case of TB and HIV-associated immune reconstitution inflammatory syndrome (IRIS). IRIS develops after antiretroviral therapy initiation. Clinically, it can present in a wide variety of ways, consistent with systemic inflammation. Even without concomitant HIV, TB can paradoxically worsen once anti-TB treatment is initiated because of immune system reconstitution, known as a “paradoxical response.” This effect is more common and prominent with concomitant initiation of HIV treatment.

Figure 55.6 shows a tuberculous pleural effusion, which is usually small to moderate in size. Diagnostic thoracentesis should be performed and ADA and lactate dehydrogenase (LDH) levels should be sent. Demonstration of an elevated pleural fluid ADA level is useful in the diagnosis of TB pleural effusion. Patients with severe symptoms of IRIS should be started on glucocorticoids to suppress the inflammatory immune response. His hyperdynamic heart suggests that heart failure is not the cause of his pleural effusion, and with hypotension, he is unlikely to benefit from diuresis. While pulmonary embolism is an important cause of respiratory failure and hypotension, it is not suggested by the ultrasound findings, which should demonstrate abnormal RV function and a dilated IVC if it is causing this degree of hemodynamic insult.

1. Naidoo K, Yende-Zuma N, Padayatchi N, et al. The immune reconstitution inflammatory syndrome after antiretroviral therapy initiation in patients with tuberculosis: findings from the SAPiT trial. Ann Internal Med. 2012;157(5):313-324. doi:10.7326/0003-4819-157-5-201209040-00004.

7. Correct Answer: D. Hepatic hydrothorax

Rationale: Hepatic hydrothorax is defined as the presence of pleural effusion in a patient with cirrhosis who does not have other reasons to have pleural effusion. Hepatic hydrothorax is a right-sided effusion in approximately 85% of cases. It is thought to be caused by the movement of ascites into the chest via diaphragmatic defects, driven by a pressure gradient from the peritoneal to the pleural space. The lack of infectious symptoms and hyperdynamic ventricles makes empyema, parapneumonic effusion, and CHF less likely.

1. Garbuzenko DV, Arefyev NO. Hepatic hydrothorax: an update and review of the literature. World J Hepatol. 2017;9(31):1197-1204. doi:10.4254/wjh.v9.i31.1197.

8. Correct Answer: B. Order CT chest angiogram and initiate a heparin infusion

Rationale/Critique: Figure 55.8 shows a trace or small right-sided pleural effusion, evidenced by the spine sign (Figure 55.16).