title: Experimental repair of tracheal defects using a new biodegradable membrane.
abstract: BACKGROUND
  The increasing number of newborns requiring intubation and artificial ventilation in the sophisticated premature and intensive care units of recent years has been followed by a concomitant increase in the number of children who develop tracheal stenosis as a sequela of prolonged intubation, with a consequent increasing need for tracheal surgical repair. This study was designed to evaluate the ability of a new tissue-engineered biodegradable membrane to tightly seal significant tracheal defects.
  
  
  METHODS
  A surgically induced tracheal defect of 10 x 5 mm was repaired in rabbits using the NVR-7 membrane--a cross-linked copolymer derived from a dextran sulphate gelatin construct. The unique features of this new membrane are biocompatibility, biodegradability, elasticity, and suturability, as well as a smooth sterilization process. The animals were sacrificed and the tracheas examined at 2, 3, 4, and 8 weeks postsurgery.
  
  
  RESULTS
  Seven (7) of 8 rabbits undergoing tracheal surgery survived, with a tight air seal and an almost normal airway. Macroscopic and microscopic studies of the removed specimens showed variable degrees of immunogenic reaction toward the membrane. In the long term (2-3 months), a complete regeneration of all the tracheal layers occurred, simulating the original structure and orderly arrangement of a normal trachea.
  
  
  CONCLUSIONS
  The surgical correction using the above membrane enabled the operated animals to overcome any respiratory distress, adequately correcting the induced tracheal defect. From this experimental study, we conclude that the new NVR-7 membrane appears to be a promising therapeutic adjunct in the treatment of patients with tracheal defects.
authors.affiliation: Department of Pediatric Surgery, Assaf Harofeh Medical Center, Zerifin, Israel. klin2@netvision.net.il
authors.forename: Baruch
authors.initials: B
authors.lastname: Klin
authors.forename: Mark
authors.initials: M
authors.lastname: Weinberg
authors.forename: Itzhak
authors.initials: I
authors.lastname: Vinograd
authors.forename: Judith
authors.initials: J
authors.lastname: Sandbank
authors.forename: Yariv
authors.initials: Y
authors.lastname: Siman-Tov
authors.forename: Liliana
authors.initials: L
authors.lastname: Astachov
authors.forename: Oran
authors.initials: O
authors.lastname: Ayalon
authors.forename: Shimon
authors.initials: S
authors.lastname: Rochkind
authors.forename: Abraham
authors.initials: A
authors.lastname: Shahar
authors.forename: Zvi
authors.initials: Z
authors.lastname: Nevo
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D019902:Chondrocytes / Q000473:pathology; D016264:Dextran Sulfate / Q000737:chemistry; D004195:Disease Models, Animal; D004548:Elasticity; D004848:Epithelium / Q000473:pathology; D005347:Fibroblasts / Q000473:pathology; D005780:Gelatin / Q000737:chemistry; D008567:Membranes, Artificial; D011108:Polymers / Q000737:chemistry; D011817:Rabbits; D019651:Plastic Surgery Procedures; D012038:Regeneration / Q000502:physiology; D013242:Sterilization; D013499:Surface Properties; D013537:Sutures; D014132:Trachea / Q000473:pathology / Q000601:surgery; D014133:Tracheal Diseases / Q000601:surgery*; D014945:Wound Healing / Q000502:physiology
chemical_list: D001672:Biocompatible Materials; D008567:Membranes, Artificial; D011108:Polymers; D005780:Gelatin; D016264:Dextran Sulfate