This biocompatible material with very low risk of toxicity can be very easily applied through a small hole in the thorax. "Although there are different polyurethane foams for medical use, the innovative aspect of this method is that the foam is generated at the very moment it is placed in the cavity, mixtured with two liquid components", as explained by Professor of Inorganic Chemistry José Miguel Martín Martínez and chemist Alfonso de Lucas, both from the Adhesion and Adhesive Lab.
"When injected into the patient, the material foams touching the damp walls of surrounding tissues by creating a very compact surface area that acts as a mold that fully fills the entire volume of the pleural cavity. Therefore, the polyurethane foam adapts to the entire gap and prevents further complications in lung patients such as infections, inflammation, bleeding, pain or fistulas, according to the University of Alicante researchers.
Other than being a lightweight material, it does not adhere to the tissue walls and thus, prevents breakage problems if extraction is necessary. "As far as we know, there is no history of using polyurethane foams for filling the pleural cavity," José Miguel Martín stated.
Effective and non-aggressive
There are several pathological processes where the pleural cavity presents air or other biological fluids such as pus or blood that are solved by simple drainage. However, especially after lung cancer surgery or severe lung infections, fluids can be accumulated with germs difficult to eradicate even using antibiotics or drainage. At this point, patients suffer progressive deterioration, pain, fever, choking and even death if not treated in time. "The filling and sealing of the pleural cavity with polyurethane foam would avoid liquid retention and would not leave gaps for the development of bacteria which means a definitive control of infection," as explained by Albacete University Hospital Complex thoracic surgeon Carlos Rombolá.
The treatments applied for the final sealing of chronic pleural cavities are large and aggressive interventions such as thoracic windows or pleural drainage. In fact, since the beginning of the 20th century, we have been trying to fill chronic pleural cavities with various substances such as air, oils, paraffin and silicones unsuccessfully. Today, thanks to these innovative polyurethane foams with self-expanding and self-molding features, "we would avoid large surgeries with a single orifice and the mixing of two liquid substances," as José Miguel Martín and Carlos Rombolá reported.
Images of polyurethane foams and chemicals from the UA Adhesion and Adhesives Lab, Alfonso de Lucas Freile and José Miguel Martín Martínez Author: Roberto Ruiz
Photo of the Albacete University Hospital Complex of Albacete medical team: Mercedes Cambronero Aroca; Marta Genoves Crespo; Carlos A. Rombola; Monica Gómez-Juarez Sango. Author: Albacete University Hospital Complex
SEM micrographs at 40x magnification of polyurethane foam Images courtesy of the UA Adhesion and Adhesives Lab
Voice clip of UA Adhesion and Adhesives Lab Professor of Inorganic Chemistry Jose Miguel Martin Martinez
Universidad de Alicante Carretera de San Vicente del Raspeig s/n 03690 San Vicente del Raspeig Alicante (Spain)