title: Effect of Plasma Sterilization on the Hemostatic Efficacy of a Chitosan Hemostatic Agent in a Rat Model.
abstract: BACKGROUND
  The United States military has had success with chitosan (CS)-based hemostatic agents to control trauma-induced hemorrhages. Despite the positive reviews, additional physical forms of CS may enhance its hemostatic efficacy. Additionally, standard sterilization techniques may negatively affect the hemostatic efficacy of CS. We studied the effects of a CS-based hemostatic pad, the Clo-Sur P.A.D.™ (Scion Cardio-Vascular, Inc.), on severe femoral vessel bleeding in a rat model. The effects of different sterilization techniques on the bioadhesivity, surface atomic concentrations, and hemostatic efficacy of the P.A.D. were also evaluated.
  
  
  METHODS
  Hemostatic efficacy, bioadhesivity, and surface atomic concentrations of the P.A.D. were evaluated in its unsterilized form, after sterilization with standard e-beam treatment, and after sterilization with one of three types of non-thermal nitrogen plasma: nitrogen gas, air, or nitrous oxide plasma. After standardized puncture of the femoral artery or transection of the femoral vessels, rats were treated with either a CS P.A.D. or gauze pad.
  
  
  RESULTS
  The Clo-Sur P.A.D., regardless of sterilization technique, stopped arterial and mixed arterial/venous bleeding in all cases in <90 s with the time to hemostasis (TTH) significantly less for all P.A.D. treatment groups (P < 0.001; n = 4-5/group) compared to gauze-treated controls (n = 3). E-beam sterilized P.A.D.s consistently showed non-significant trends toward increased TTH and worse hemostasis scores compared to unsterilized and plasma sterilized P.A.D.s. Treating e-beam sterilized P.A.D.s with N2 plasma reverted the hemostatic efficacy to levels equivalent to native, unsterilized PADs.
  
  
  CONCLUSIONS
  A CS-based hemostatic pad successfully controlled severe bleeding in a rat model with combined e-beam and plasma sterilized P.A.D.s showing the most promising results. Further studies are warranted.
authors.affiliation: Department of Anatomy, School of Medicine, Loma Linda University, Loma Linda, CA, USA.|Neurosurgery Center for Research, Training, and Education, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Crofton
authors.affiliation: Animal Care Facility, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
authors.forename: John
authors.initials: J
authors.lastname: Chrisler
authors.affiliation: College of Textiles, North Carolina State University, Raleigh, NC, USA.
authors.forename: Samuel
authors.initials: S
authors.lastname: Hudson
authors.affiliation: Department of Orthopedic Surgery, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
authors.forename: Serkan
authors.initials: S
authors.lastname: Inceoglu
authors.affiliation: Neurosurgery Center for Research, Training, and Education, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
authors.forename: Floyd
authors.initials: F
authors.lastname: Petersen
authors.affiliation: Neurosurgery Center for Research, Training, and Education, School of Medicine, Loma Linda University, Loma Linda, CA, USA. wkirsch@llu.edu.|Division of Biochemistry, School of Medicine, Loma Linda University, Loma Linda, CA, USA. wkirsch@llu.edu.
authors.forename: Wolff
authors.initials: W
authors.lastname: Kirsch
mesh_terms: D000818:Animals; D001458:Bandages; D048271:Chitosan / Q000008:administration & dosage*; D004195:Disease Models, Animal; D005263:Femoral Artery; D006470:Hemorrhage / Q000628:therapy*; D006490:Hemostatics / Q000008:administration & dosage*; D051381:Rats; D013242:Sterilization / Q000379:methods*; D014481:United States; D014947:Wounds and Injuries / Q000628:therapy*
chemical_list: D006490:Hemostatics; D048271:Chitosan
keywords: Chitosan; Hemostasis; Hemostatic agents; Non-thermal nitrogen plasma; Plasma sterilization; Rat model