Minirigid Versus Conventional Rigid Thoracoscopy in Undiagnosed Pleural Effusions (MICRO)

A Randomized Trial Comparing the Diagnostic Sensitivity and Safety of Mini-thoracoscopy Versus Conventional Rigid Thoracoscopy in Undiagnosed Pleural Effusions

Consecutive patients who are planned to undergo a medical thoracoscopy for obtaining pleural biopsies will be enrolled in the study. One hundred subjects will be randomized in 1:1 ratio to undergo thoracoscopy to the following groups: Group A (mini-thoracoscopy) Group B (Conventional rigid thoracoscopy) Primary outcome: (a) diagnostic sensitivity of mini-thoracoscopy and conventional rigid thoracoscopy in the diagnosis of exudative pleural effusions

A significant proportion of patients with pleural effusions remain undiagnosed after performance of diagnostic procedures including cytological and microbiologic analysis of the pleural fluid and closed pleural biopsies. In this study, the investigators plan to compare the yield and safety of mini-thoracoscopy and conventional rigid thoracoscopy with the larger diameter scope. This is a prospective study that will be conducted at the Thoracic Endoscopy Suite of the Department of Pulmonary Medicine, PGIMER, Chandigarh. Consecutive patients who are planned to undergo a medical thoracoscopy for obtaining pleural biopsies will be enrolled in the study One hundred subjects will be randomized in 1:1 ratio to undergo thoracoscopy. The randomization sequence will be generated using a computer (in blocks of 10), and the allocation will be placed in opaque sealed envelopes. The patients will be randomized to the following groups: Group A (mini-thoracoscopy): The mini-thoracoscope manufactured by Richard Wolf GmbH, Knettligen, Germany will be used. It has an outer diameter of 5.5 mm and a working channel diameter of 3.5 mm. Group B (Conventional rigid thoracoscopy): The rigid thoracoscope manufactured by Richard Wolf GmbH, Knettligen, Germany will be used that has an outer diameter of 10 mm and channel internal diameter of 5 mm. Primary outcome: (a) diagnostic sensitivity of mini-thoracoscopy and conventional rigid thoracoscopy in the diagnosis of exudative pleural effusions.

The mini-thoracoscope manufactured by Richard Wolf GmbH, Knettligen, Germany will be used for performing thoracoscopic pleural biopsies. It has an outer diameter of 5.5 mm and a working channel diameter of 3.5 mm.

The rigid thoracoscope manufactured by Richard Wolf GmbH, Knettligen, Germany will be used for performing thoracoscopic pleural biopsies. It has an outer diameter of 10 mm and channel internal diameter of 5 mm.

Difference between the diagnostic sensitivity of mini-thoracoscopy and conventional rigid thoracoscopy in the diagnosis of exudative pleural effusions by calculating the number of true positives diagnosed by thoracoscopic biopsy in the two groups out of the total diseased

Diagnostic sensitivity of mini-thoracoscopy and conventional rigid thoracoscopy in the diagnosis of exudative pleural effusions by calculating the number of true positives diagnosed by thoracocopic biopsy. In this analysis, the subjects crossed over to the rigid group (due to failure of minirigid to yield biopsy tissue) will be considered in the rigid group

Difference between intraoperative pain score associated with the use of the two devices (assessed after the procedure using the visual analog scale from 0-no pain to 100-maximum possible pain) in the two groups

Difference between the diagnostic specificity of mini-thoracoscopy and conventional rigid thoracoscopy in the diagnosis of exudative pleural effusions by calculating the number of true negatives diagnosed by thoracoscopic biopsy in the two groups out of those not diseased

Differences between number of participants with treatment-related adverse events as assessed by CTCAE v4.0 in the two groups

Differences between maneuverability of the two thoracoscopes on a visual analog scale (0-100 mm) assessed by the operator

Differences between ease of obtaining pleural biopsy with the two thoracoscopes on a visual analog scale (0-100 mm) assessed by the operator

Difference between intraoperative pain score associated with the use of the two devices (assessed after the procedure using the Wong Baker FACES pain rating scale) in the two groups

Inclusion Criteria: Medical thoracoscopy being performed for obtaining a pleural biopsy Exclusion Criteria: PaO2/FIO2< 300; Hemodynamic instability Myocardial infarction or unstable angina in the last 6 wk Lack of pleural space due to adhesions Uncorrected coagulopathy Failure to provide informed consent