Elevated Pleural Elastance Common in Malignant Pleural Effusion After Thoracentesis

In patients with malignant pleural effusion, elevated pleural elastance (E-P_EL) and incomplete lung expansion are frequently observed after thoracentesis. These findings were published in CHEST.

A total of 70 consecutive patients with malignant pleural effusion were retrospectively identified and included in the analysis. Only patients who received complete therapeutic pleural drainage with concomitant pleural manometry were included. Immediately after thoracentesis, a post-thoracentesis anteroposterior view chest radiograph was performed. To determine the frequency of E-P_EL and the association of P_EL with post-thoracentesis chest radiographic findings, researchers constructed and examined pressure/volume curves.

E-P_EL was observed in more than half (51.4%) of patients, and approximately 54% of patients had incomplete lung expansion. Patients with normal P_EL had significantly different odds of having complete lung expansion compared with those with an E-P_EL (odds ratio for P_EL, 6.3; P =.0006).

In 29% of patients, there was an observable discordance between postprocedural chest radiographic findings and results from the pleural manometry, which suggests that postpleural drainage findings on chest radiograph alone are both inadequately sensitive and specific to detect E-P_EL. Approximately 28% of patients with complete lung expansion on the postdrainage chest radiograph had E-P_EL. In 34% of patients with incomplete lung expansion as detected by post-thoracentesis chest radiograph, P_EL was normal.

Limitations of the study included the retrospective nature, the inclusion of patients from a single center, and the lack of investigation into the mechanisms that contributed to the discordance between incomplete lung expansion and E-P_EL results.

According to the study investigators, the findings “suggest that pleural manometry may have a role in addition to the post-thoracentesis chest radiograph in selecting patients for pleurodesis; however, confirmation of this conjecture would require a similar study to ours plus an analysis of pleurodesis outcomes.”

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Chopra A, Judson MA, Doelken P, Maldonado F, Rahman N, Huggins JT. The relationship of pleural manometry with post-thoracentesis chest radiographic findings in malignant pleural effusion [published online August 28, 2019]. CHEST. doi:10.1016/j.chest.2019.08.1920