Table 1

Secondary objectives and associated end points in the pre-EDIT study

Secondary objectivesSecondary end points
To determine the feasibility of PEL computation using the novel DPMThe time taken to perform the EDIT large volume aspiration, including measurement of ΔIPP using the DPM, recording of ΔV and computation of PEL
The failure rate of the procedure, defined as the proportion of patients in whom PEL cannot be computed
To determine the safety and tolerability of PEL computation using the novel DPMThe occurrence of chest pain, cough or breathlessness during the procedure
AEs) and SAEs associated with use of the DPM
To assess the pleural fluid aspiration volume required to detect abnormal PEL (where present)The pleural fluid aspiration volume at which the rolling average pleural elastance over the preceding 250 mL (PEL250) first exceeds the upper limit of normal (14.5 cm H2O/L)
To determine the proportion of patients allocated to EDIT management who require pneumothorax induction to facilitate safe ICD/IPC insertion following DPMThe proportion of patients in whom pneumothorax induction is required to facilitate safe ICD/IPC insertion in the EDIT arm
To test the assumption that pleural cavity ΔV is equivalent to the volume of pleural fluid removed during aspirationPleural fluid aspiration volume (ΔVOUT)
Pleural cavity volume change, as measured directly using volumetric MRI (ΔVMRI; defined as pre-aspiration minus post-aspiration pleural cavity volume)
To test the accuracy of a predictive model of pleural effusion volume (VTUS) based on TUS measurements, which is a proposed inclusion criterion for the EDIT studyTUS estimated total pleural effusion volume (VTUS)
Pre-pleural fluid aspiration pleural cavity volume (VMRI)
  • AE, adverse events; DPM, digital pleural manometer; EDIT, elastance-direct intrapleural catheter or talc pleurodesis; ICD, intercostal drain; IPC, indwelling pleural catheter; IPP, intrapleural pressure; PEL, pleural elastance; SAE, serious adverse event; TUS, thoracic ultrasound; V, pleural fluid volume.