Background: The usefulness of semirigid thoracoscopy in undiagnosed exudative pleural effusions (EPEs) has been variably reported in different studies. Herein, we perform a systematic review and meta-analysis to estimate the overall diagnostic yield and safety of semirigid thoracoscopy in EPE.
Methods: We searched the PubMed and EMBASE databases for studies reporting the outcomes of semirigid thoracoscopy in EPE. The quality of studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The yield of semirigid thoracoscopy was analyzed by calculating the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic OR (DOR) for each study and pooling the study results using a random effects model. Heterogeneity and publication bias were assessed for individual outcomes. Sensitivity analysis was performed to explore the potential causes of heterogeneity.
Results: Our search yielded 17 studies (755 patients with undiagnosed EPE). The sensitivity, specificity, PLR, NLR, and DOR of semirigid thoracoscopy was 91%, 100%, 4.92, 0.08, and 102.28, respectively. The area under the curve for the summary receiver operating characteristic curve was 0.93. There were negligible complications and no mortality. There was evidence of heterogeneity, which significantly decreased on sensitivity analysis after exclusion of smaller (< 25 participants) studies. There was no evidence of publication bias.
Conclusions: Semirigid thoracoscopy is an efficacious and safe procedure in diagnosis of EPE. Because of the small sample size, larger well-designed trials are required to confirm the results of this study. There is also a need for head-to-head comparison of semirigid and rigid thoracoscopy.