Yes, it is Safe to Drain More than 1500ml of Pleural Effusion!

​Most Swiss Guidelines recommend never to drain more than 1500ml of pleural fluid when performing a thoracocentesis. The reason is that excessive drainage might cause re-expansion pleural effusion (e.g. www.medstandards.ch). There is not much literature on the safe amount of fluid one can drain, but a clinical practice article on pleural effusions in the New England Journal of Medicine also states that "...in which case therapeutic thoracentesis to remove up to 1500 ml of fluid is indicated." (N Engl J Med 2002; 346:1971-1977).
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Interestingly there is no evidence supporting this recommendation. Some data suggests that the risk of re-expansion pulmonary oedema might correlate with the baseline size of the effusion, rather than the volume of fluid removed.​

However, the first results from research start giving us some answers and indicate that removing more than 1500ml of fluids is safe and feasible.


Ault M et al. (Thorax. 2015;70(2):127-132.) looked at 9320 patients during 11 years who underwent thoracocentesis and recorded the incidence of adverse events. They were able to show that:

• The occurrence of re-expansion pulmonary oedema is rare, also when large amounts of fluids are drained

 

• No patient died due to this intervention

Lentz RJ et al. (Lancet Respir Med. 2019;7(5):447-455.) showed that

• The use of manometry during thoracocentesis does not influence patient outcome.

All the details and lots of background information are very nicely summarized in this fabulous post on emcrit.org:

PulmCrit - Large volume thora: Can we drain 'em dry?