title: The efficacy of a novel chitosan gel on hemostasis after endoscopic sinus surgery in a sheep model of chronic rhinosinusitis.
abstract: BACKGROUND
  Postoperative bleeding remains a major problem after endoscopic sinus surgery (ESS). Patients who continue to bleed after ESS are at risk of airway compromise from inhalation of blood clots or from aspiration of blood-stained vomitus. The aim of this study was to determine the in vivo efficacy of a novel gel on hemostasis after ESS in a sheep model of chronic rhinosinusitis.
  
  
  METHODS
  Twenty-one sheep infested with Oestrus ovus underwent ESS with standardized mucosal injuries created at the anterior ethmoid region using a microdebrider. Immediately after injury a baseline bleeding time was taken using the Boezaart Surgical Field Grading Scale. Computer randomization was performed to either receive chitosan/dextran (CD) gel or no treatment (control). Boezaart bleeding scores were calculated for each side every 2 minutes. Each postoperative day videoendoscopy was performed to document crusting/CD gel dissolution.
  
  
  RESULTS
  The CD gel side was significantly more hemostatic at 2, 4, and 6 minutes after injury. Average time to hemostasis was significantly better for the intervention side versus control side, 4.09 (+/-1.61) versus 6.57 (+/-2.20), respectively (p = 0.049). Complete hemostasis occurred by 6 minutes for all CD gel sides; however, control side bleeding was noted on three sides at 8 minutes and on one side at 10 minutes. There was no significant difference in crusts scores at days 1, 3, 7, and 14.
  
  
  CONCLUSIONS
  In the sheep model of ESS, CD gel significantly improved hemostasis compared with the control at 2, 4, and 6 minutes after mucosal injury.
authors.affiliation: Department of Surgery-Otorhinolaryngology, Head and Neck Surgery University of Adelaide, Adelaide, Australia.
authors.forename: Rowan
authors.initials: R
authors.lastname: Valentine
authors.forename: Theo
authors.initials: T
authors.lastname: Athanasiadis
authors.forename: Stephen
authors.initials: S
authors.lastname: Moratti
authors.forename: Simon
authors.initials: S
authors.lastname: Robinson
authors.forename: Peter-John
authors.initials: PJ
authors.lastname: Wormald
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D048271:Chitosan / Q000008:administration & dosage*; D004195:Disease Models, Animal; D004724:Endoscopy / Q000379:methods*; D015521:Ethmoid Sinusitis / Q000601:surgery*; D005782:Gels; D016558:Hemostasis, Endoscopic / Q000379:methods*; D006490:Hemostatics / Q000008:administration & dosage; D013517:Otorhinolaryngologic Surgical Procedures / Q000379:methods*; D019106:Postoperative Hemorrhage / Q000628:therapy*; D012220:Rhinitis / Q000601:surgery*; D012756:Sheep; D014741:Video Recording
chemical_list: D005782:Gels; D006490:Hemostatics; D048271:Chitosan