Sensitivity of chest x-ray for visualisation of one brand of indwelling pleural catheter

Introduction: Correct placement of indwelling pleural catheters (IPCs) is often confirmed on chest x-ray (CXR). Recent anecdotal reports suggest a brand of IPCs (Rocket) may be difficult to visualise due to a thinner barium stripe. This study aims to evaluate the sensitivity of CXR for detecting these IPCs. Methods: Medical records of patients who underwent IPC insertion at a regional Australian tertiary centre in the 15 months to January 2023 were retrospectively reviewed. Records were reviewed for patient demographics, mention of an IPC or drain in the CXR request and/or by the radiologist in their final report. Subsequent identification on thoracic ultrasound, computed-tomography (CT) scan or uncomplicated drainage by nurses was considered evidence that the IPC was correctly sited. Results: 13 (Rocket) IPCs were inserted into 11 patients. 35 CXRs were performed with a median of 2 (IQR 1-4) CXRs per patient. IPCs were identified on 16/35 occasions, giving a sensitivity of 46% (95% CI 26-62%). This rose to 69% (11/16) when the IPC was mentioned in the request. On one occasion the IPC was incorrectly reported as extra-thoracic. No adverse events occurred due to the IPC not being seen on CXR. All the relevant IPCs came from specific lots which had a thinner barium stripe. Conclusions: This study suggests that at least a subgroup of (Rocket) IPCs are poorly seen on CXR. This may have implications for the detection of complications, compromise clinical decision making, or require additional imaging. (Rocket) has withdrawn the relevant devices from the market, but these catheters remain in-situ for many patients worldwide and radiology and pleural services should be aware of this issue.