Chemical pleurodesis – a review of mechanisms involved in pleural space obliteration

Abstract

Chemical pleurodesis is a therapeutic procedure applied to create the symphysis between the parietal and visceral pleura by intrapleural administration of various chemical agents (e.g. talk, tetracycline, iodopovidone, etc.). The two major clinical conditions treated with chemical pleurodesis are recurrent pleural effusion (PE) and recurrent spontaneous pneumothorax. Although the history of chemical pleurodesis began over a century ago, detailed data on the mechanisms of action of sclerosing agents are highly incomplete. The following article aims to present the state of knowledge on this subject.It is believed that mesothelial cells are the main structural axis of pleurodesis. In response to sclerosing agents they secrete a variety of mediators including chemokines such as interleukin 8 (IL-8) and monocyte chemoattractant protein (MCP-1), as well as growth factors - vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF) and transforming growth factor- β (TGF-β). Numerous data suggest that intact mesothelial cells and the above cytokines play a crucial role in the initiation and maintenance of different pathways of pleural inflammation and pleural space obliteration.It seems that the process of pleurodesis is largely nonspecific to the sclerosant and involves the same ultimate pathways including activation of pleural cells, coagulation cascade, fibrin chain formation, fibroblast proliferation and production of collagen and extracellular matrix components. Of these processes, the coagulation cascade with decreased fibrinolytic activity and increased fibrinogenesis probably plays a pivotal role, at least during the early response to sclerosant administration.A better understanding of various pathways involved in pleurodesis may be a prerequisite for more effective and safe use of various sclerosants and for the development of new, perhaps more personalized therapeutic approaches.

Spontaneous subcutaneous emphysema and pneumomediastinum in non-intubated patients with COVID-19

“…While the possibility that small apical radiographically occult pneumothoraces may have been present, an alternative explanation may lie in the current or prior pulmonary inflammatory process, which can form pleural adhesions between parietal and visceral layers of the pleura. Such adhesions can protect against development of pneumothoraces, as illustrated by the concept of pleurodesis in which the pleural space is artificially obliterated and subsequently adhesed to treat recurrent spontaneous pneumothorax [ 34 ].…”

Primary human mesothelial cell culture in the evaluation of the inflammatory response to different sclerosing agents used for pleurodesis

“…IL-1, IL-6, IL-8, interleukin 1, 6 and 8; PVP-I, iodopovidone; TGF-β, transforming growth factor β fluid correlated negatively with pleural fluid tPA levels (Cl et al, 2005). That may suggest that IL-1β is an important player in inflammation, fibrosis, and coagulation pathways activated in the process of pleurodesis (Mierzejewski et al, 2019). Pro-inflammatory mesothelial response manifested by tendency in increasing IL-1β protein production found in our study seems to be in line with the above considerations and suggests the role of IL-1β in the formation and maintenance of the inflammatory response in the course of pleurodesis.…”

“…Subsequently, other cell populations including neutrophils, fibroblasts, and macrophages are involved. IL-8 and neutrophils seem to be critically important in the initiation and maintenance of pleural inflammation (Psathakis et al, 2006) Numerous other mediators have also been shown to play a role in this process, including TGF-β, basic fibroblast growth factor (bFGF), and pro-inflammatory cytokines IL-6, IL-1 (Mierzejewski et al, 2019).…”

Effects of Different Applications on Postoperative Seroma Formation and Wound Healing Following Mastectomy and Axillary Dissection in Rats

“…As sclerosant agents, tetracycline, talc, iodopovidone are used to achieve chemical pleurodesis by triggering an inflammatory response [17,18]. According to Rice et al and Mc-Carthy et al, local tetracycline application had no effect on seroma formation after mastectomy and was associated with severe pain [19,20].…”