Biological Mechanisms and Therapeutic Potential of PRP-Fibrin Glue in Managing Refractory Pleural Effusion: Insights from a Pilot Study

Background: Refractory pleural effusion (RPE) is a serious post-cardiac surgery complication, often unresponsive to conventional chest tube drainage. This pilot clinical trial investigates platelet-rich plasma fibrin glue (PRP-FG), a non-invasive treatment previously effective for postoperative chylothorax and pneumothorax, to assess its efficacy in managing RPE resistant to standard thoracostomy. Methods: The study enrolled 19 patients with unilateral or bilateral RPE unresponsive to conventional treatment. The primary outcome was successful treatment, defined as pleural effusion volume <50 mL/day for two consecutive days within one-week post-treatment, accompanied by symptomatic improvement. Results: Participants had a mean age of 43.58 ± 19.58 years, with 52.6% having undergone coronary artery bypass grafting (CABG) and 36.8% congenital cardiac surgery. All patients showed reduced effusion volumes post-PRP-FG treatment. However, five patients (26.3%) required a second PRP-FG application, and three (15.8%) needed a third to achieve optimal outcomes. Pleural effusion volume significantly decreased from 624.21 ± 275.02 mL to 25.00 ± 20.07 mL (mean difference: 599.21 mL, p < 0.001, effect size d = 2.29). No recurrence of effusion was observed during follow-up. No severe adverse effects were reported; minor side effects, such as pleuritic pain and transient dyspnea, were managed with symptomatic treatment. One patient with poorly controlled diabetes died due to an unrelated sternal wound infection. Conclusion: PRP-FG offers a safe, cost-effective, and minimally invasive treatment for RPE resistant to conventional methods. Larger, multicenter studies with extended follow-up are warranted to confirm its efficacy in managing persistent pleural effusion.