Stop Air Leak by Talc or Autologous Blood Patch Therapy

Background: A pilot study to assess the feasibility of a randomisation trial protocol comparing intrapleural talc pleurodesis versus autologous blood patch therapy (ABPT) in patients with secondary spontaneous pneumothorax (SSP) complicated by persistent air leak (PAL). The investigators hypothesise that the proposed protocol will be feasible. Methods: A multicentre, two-arm, open-label, randomised controlled feasibility study which includes non-surgical subjects with SSP and PAL persisting for 3 days. Recruited subjects will be randomised in a 1:1 ratio to receive one dose of talc pleurodesis or ABPT, with follow-ups up to 3 months after hospital discharge. Discussion: The main outcome is to assess the feasibility of the trial protocol, based on the percentage of eligible patients enrolled and randomised, retained to discharge, and completing 3 months of follow-up. Other important outcomes include complete cessation of air leak and successful chest drain removal within 72 hours after the study intervention, absolute and percentage changes in digitally measured air leak rates, duration of chest drainage, recurrence of ipsilateral pneumothorax, need for additional pleural interventions, safety outcomes such as drain blockage and pleural infection. Feasibility outcomes will be reported as descriptive data. Comparison of outcomes between the two treatment groups will be analysed on an intention-to-treat basis. Safety outcomes will be reported descriptively for each group. The reported estimates of recruitment rates, adherence, follow-up completeness, and variability and event rates for key clinical outcomes will be used to inform sample size calculations for future studies incorporating the current study design.

Inclusion Criteria: * Age 18 years or older * Radiographically proven pneumothorax and underlying lung disease (either pre-existing or shown in diagnostic imaging at presentation) * Spontaneous onset of pneumothorax, not related to trauma or iatrogenic procedure * SSP with air leak persists for at least 2 days after the first radiographic evidence of pneumothorax * Not suitable, as decided by the attending medical or surgical team, or the patient is unwilling to receive surgical management for the pneumothorax Exclusion Criteria: * Inability to give informed consent * A chest drain size smaller than Fr 12 * Bilateral pneumothorax. * Impaired blood clotting, including baseline INR \> 1.5, platelet \< 150 x 109/L, or use of therapeutic dose anticoagulant or dual-antiplatelet agents. * Active or recent (within 6 weeks) ipsilateral pleural infection. * Septicemia or active extra-pleural infection (e.g. pneumonia). * Use of long-term systemic corticosteroids or immunosuppressant. * Previously received talc or ABPT to the ipsilateral pleural space for the current episode of pneumothorax. * Known sensitivity to talc. * Has had a previous pneumonectomy (either on the same or contralateral side). * Patients who are pregnant or lactating (females of childbearing potential must have a negative pregnancy test before randomisation). * Expected survival of less than three months from a different pathology to the current episode of pneumothorax (e.g. metastatic malignancy). * Cognitively impaired patients who are at risk of self-removing the chest drain