Intrathoracic vacuum therapy for the therapy of pleural empyema-a systematic review and analysis of the literature

Pleural empyema is a serious and potentially deadly disease leading to a significant burden on health care systems. Conservative and surgical treatment results remain poor, with high morbidity and mortality rates. Patients with pleural empyema are often multimorbid and poor candidates for surgery. Therefore, it appears sensible to explore alternative, less invasive treatment options. Recently, the well-established vacuum sponge therapy has been adopted in the treatment of pleural infections. The goal of this systematic review was to identify the existing literature and reported results of vacuum therapy for pleural empyema. A systematic search of MEDLINE and the Cochrane Database was performed independently by two reviewers using predefined criteria according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. In addition, abstracts from selected conference proceedings were screened and reference scanning of the search results was performed. Single case reports were excluded. Fourteen studies met the selection criteria and were reviewed. A total of 165 patients were treated with vacuum therapy in the studies reviewed. 61.2% of the patients had pleural empyema secondary to thoracic surgery. In 71.5% of the patients, vacuum therapy was applied following open window thoracostomy (OWT). Mortality rates of 0-33% were reported for vacuum therapy after OWT and 0-9.3% for vacuum therapy without OWT. Length of hospital stay (LOHS) ranged from 44-217 days for patients after OWT and could not be analysed for vacuum therapy without OWT due to lacking data. Median treatment time was 7-14 days. Treatment related complications were rare overall. Success rates defined as infection resolution were high irrespective of previous treatment and cause of empyema. The current literature shows that pleural vacuum therapy is a promising, safe, and feasible treatment alternative to existing treatment modalities for pleural empyema. However, the evidence for vacuum therapy without OWT is poor, and further data, optimally prospective or randomised control trials comparing the conventional surgical approach of video-assisted thoracoscopic surgery (VATS) decortication and minimally invasive vacuum therapy, are needed.