title: In vitro effect of multiple hydrogen peroxide gas plasma sterilizations on the rate of closure of ameroid constrictors.
abstract: OBJECTIVE
  To evaluate the effect of multiple hydrogen peroxide gas plasma (HPGP) sterilizations on the rate of closure of ameroid constrictors.
  
  
  METHODS
  Thirty-six 5.0-mm ameroid constrictors.
  
  
  METHODS
  Ameroid constrictors were randomly allocated to 6 groups. Each group underwent 1, 2, 3, 4, 5, or 6 HPGP sterilizations. Ameroid constrictors were then incubated for 35 days in canine plasma and digitally imaged at predetermined times during incubation. One individual, who was unaware of the group to which each ameroid constrictor was assigned, measured the lumen area of the constrictor on each digital image. Mean lumen area was compared among groups.
  
  
  RESULTS
  No ameroid constrictors were completely closed after 35 days of incubation in canine plasma. Mean lumen area after incubation did not differ among constrictors that underwent 1, 2, and 3 sterilizations. Constrictors that underwent 4 sterilizations were closed significantly more than were those that underwent 1, 2, or 3 sterilizations. Mean lumen area after incubation did not differ significantly between constrictors that underwent 5 and 6 sterilizations, although the final lumen areas for those constrictors were significantly smaller than those for constrictors that underwent 1, 2, 3, and 4 sterilizations.
  
  
  CONCLUSIONS
  Ameroid constrictors that underwent 5 and 6 HPGP sterilizations had a 9% to 12% decrease in lumen area, compared with that of constrictors that underwent ≤ 4 plasma sterilizations, and the use of such constrictors could increase the risk of portal hypertension and secondary acquired shunting or decrease the risk of persistent shunting.
authors.affiliation: Departments of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Thompson
authors.forename: Heather A
authors.initials: HA
authors.lastname: Towle Millard
authors.forename: George E
authors.initials: GE
authors.lastname: Moore
authors.forename: Lynn
authors.initials: L
authors.lastname: Guptill
mesh_terms: D000818:Animals; D002364:Caseins / Q000737:chemistry*; D003250:Constriction; D013505:Digestive System Surgical Procedures / Q000295:instrumentation / Q000662:veterinary*; D004285:Dogs; D020100:Hydrogels / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry / Q000494:pharmacology*; D010949:Plasma / Q000737:chemistry; D013242:Sterilization / Q000379:methods*; D013995:Time
chemical_list: D002364:Caseins; D020100:Hydrogels; C009719:ameroid; D006861:Hydrogen Peroxide