title: A randomized multicenter trial of Crotalidae polyvalent immune F(ab) antivenom for the treatment of rattlesnake envenomation in dogs.
abstract: OBJECTIVE
  To determine clinical efficacy of the Crotalidae polyvalent immune F(ab) (ovine) antivenom (OPCA) against progressive crotalid envenomation in the dog as reflected in stabilization or improvement of snakebite severity scores (SSS). Additionally, due to the potential decreased half-life of the F(ab) antibodies in dogs we compared SSS between dogs receiving 2 different dosing regimes.
  
  
  METHODS
  Prospective, clinical trial.
  
  
  METHODS
  Five veterinary emergency and critical care facilities.
  
  
  METHODS
  One hundred and fifteen client-owned Crotalid (rattlesnake) snake bitten dogs in whom worsening of the envenomation syndrome was observed before OPCA treatment.
  
  
  METHODS
  In a multicenter randomized clinical trial a single dose (1 vial) of OPCA alone was compared with 2 doses (1/2 vial each) administered 6 hours apart. Standard supportive care was provided in all cases.
  
  
  RESULTS
  Data were available for 115 patients, 9 of which were fatalities. All patients' clinical condition was documented with a standardized SSS system accounting for each major body system. Each fatality received maximum severity scores of 20. The mean severity score of the 115 patients decreased from 4.19 to 3.29 points and there was no difference between the 2 treatment groups. The mean severity score of the 107 patients without fatalities decreased from 4.16 to 2.15. Antivenin-related acute reactions occurred in 6 dogs (6%), and no serum sickness occurred within the 95 cases contacted at the 2-week posttreatment follow-up.
  
  
  CONCLUSIONS
  In the first randomized trial in dogs of antivenin in the United States, OPCA effectively stabilized or terminated venom effects. There were no statistical differences detected between treatment groups within the study time frame.
authors.affiliation: Reid Veterinary Hospital, Albany, OR 97321, USA. petersonkate@netscape.net
authors.forename: Michael E
authors.initials: ME
authors.lastname: Peterson
authors.forename: Michael
authors.initials: M
authors.lastname: Matz
authors.forename: Karen
authors.initials: K
authors.lastname: Seibold
authors.forename: Signe
authors.initials: S
authors.lastname: Plunkett
authors.forename: Scott
authors.initials: S
authors.lastname: Johnson
authors.forename: Kevin
authors.initials: K
authors.lastname: Fitzgerald
mesh_terms: D000818:Animals; D000997:Antivenins / Q000627:therapeutic use*; D003435:Crotalid Venoms / Q000037:antagonists & inhibitors / Q000276:immunology*; D017839:Crotalus; D004283:Dog Diseases / Q000628:therapy*; D004285:Dogs; D005260:Female; D007140:Immunoglobulin Fab Fragments; D007128:Immunoglobulin Fragments / Q000627:therapeutic use*; D008297:Male; D012909:Snake Bites / Q000628:therapy / Q000662:veterinary*; D016896:Treatment Outcome
chemical_list: D000997:Antivenins; D003435:Crotalid Venoms; C431183:Crotalidae Polyvalent immune Fab; D007140:Immunoglobulin Fab Fragments; D007128:Immunoglobulin Fragments