Pleural Effusion

Hiren Muzumdar

doi:10.1542/pir.33-1-45

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Hiren Muzumdar, MD

Children's Hospital at Montefiore Bronx, NY

Suggested Reading

1. Light RW
Clinical Practice: Pleural Effusion. Light RW. N Engl J Med. 2002;346(25):1971–1977
OpenUrl CrossRef PubMed
1. Soto-Martinez M,
2. Massie J
Chylothorax: Diagnosis and Management in Children. Soto-Martinez M, Massie J. Paediatr Respir Rev. 2009;10(4):199–207
OpenUrl CrossRef PubMed
1. Light RW
Parapneumonic Effusions and Empyema. Light RW. Proc Am Thorac Soc. 2006;3(1):75–80
OpenUrl CrossRef PubMed
1. Shah SS,
2. Hall M,
3. Newland JG,
4. et al
Comparative Effectiveness of Pleural Drainage Procedures for the Treatment of Complicated Pneumonia in Childhood. Shah SS, Hall M, Newland JG, et al. J Hosp Med. 2011;6(5):256–263
OpenUrl CrossRef PubMed
1. Ayres J,
2. Gleeson F
Imaging of the Pleura. Ayres J, Gleeson F. Semin Respir Crit Care Med. 2010;31(6):674–688
OpenUrl CrossRef PubMed

Author Disclosure
Dr Muzumdar has disclosed no financial relationships relevant to this article. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.

Pleural effusions are abnormal collections of fluid in the pleural space, which is a potential space between the parietal (chest cavity) pleura and the visceral (lung) pleura. Normally, the pleural space contains a small amount of fluid having a low protein concentration of 1 g/dL that is formed in the apical region of the parietal pleura and is drained through the lymphatic system. Very little fluid moves across the visceral pleura, except in the presence of pulmonary venous hypertension. Pleural effusions may be transudates caused by an imbalance of hydrostatic and oncotic pressures across intact vasculature or exudates resulting from fluid moving across leaky blood vessels into the pleural space.

Transudative pleural effusions most commonly result from heart failure, hepatic cirrhosis, nephrotic syndrome, or peritoneal dialysis. Left heart failure increases pulmonary venous pressure, which in turn forces fluid across the visceral pleura into the pleural space. Restriction to mitral flow, as with mitral stenosis, does the same, but only rarely does right heart failure or pulmonary arterial hypertension cause excessive fluid to accumulate in the pleural space.

With hepatic cirrhosis, pleural effusions develop from leakage of transudative ascitic fluid into the pleural space across minor defects in the diaphragm, usually on the right side. Similarly, a pleural effusion can accumulate during peritoneal dialysis when dialysate leaks from the abdomen.

Nephrotic syndrome is marked by a reduction in oncotic pressure from hypoalbuminemia and by increased hydrostatic pressure from compensatory hypervolumia, both of which contribute to fluid moving into the pleural space. Rarely, hypercoagulability from nephrosis may result in pulmonary embolism that can cause an exudative pleural effusion.

In contrast to transudates, pleural exudates …