Development of an insoluble hyaluronic acid membrane as an effective material for the prevention of post-thoracotomy pleural adhesions in dogs

Abstract

A novel membrane was previously found to be effective in preventing post-thoracotomy pleural adhesions in
dogs. The aim of the present study was to verify the animals’ clinical condition, the biological fate of the residual
membrane, the presence or absence of pleural adhesions, and any inflammatory reactions over a 10-week observation
period following membrane implantation. The animals used were two male beagles. The experimental membrane, an
insoluble hyaluronic acid membrane containing glycerin, was implanted under general anesthesia above the visceral
pleura in the left pleural cavity of each dog after exposure to air for 30 min. A drainage tube was installed, and the
incision was closed. The drainage tube was removed after confirming the absence of pleural effusion. Ten weeks after
implantation of the experimental membrane, the dogs were sacrificed, and their chests were re-opened with a median
sternotomy to examine adhesions. Macroscopic examination at the end of the observation period showed a total absence
of pleural adhesions in both dogs, without complications of wound healing at the suture sites on the chest wall, and no
findings suggested any inflammatory response. Based on these results, this experimental membrane can prevent
postoperative pleural adhesions in dogs.