title: Heartworm-positive dogs recover without complications from surgical sterilization using cardiovascular sparing anesthesia protocol.
abstract: Expedited home placement of heartworm-positive shelter dogs is desirable and may outweigh the perceived increase in anesthetic risk for pre-adoption sterilization; however, this issue has not been addressed in the literature. Our goal was to determine whether heartworm-positive dogs suffered clinically evident perioperative complications after sterilization under general anesthesia. Anticipated complications could result from anesthesia-induced changes in pulmonary vascular resistance and cardiac output leading to signs of thromboembolic disease and even death from dislodged parasites. The medical records of 15 hemodynamically stable, intact, heartworm-positive, mixed-breed shelter dogs with no or mild clinical signs were examined. Pre-operative evaluation of patients included a complete blood count, clinical chemistry profile, heartworm antigen and microfilariae screen, electrocardiogram, and thoracic radiographs. The anesthetic protocol for heartworm-positive dogs included acepromazine (0.01-0.05 mg/kg), butorphanol (0.1mg/kg IM) and meloxicam (0.2mg/kg IM), or carprofen (2mg/kg SQ) in the preanesthetic period; tiletamine/zolazepam (3-6 mg/kg IV) or ketamine/diazepam (3-6mg/kg/0.25-5mg/kg IV) to effect for induction; maintenance on isoflurane or sevoflurane and oxygen. A lidocaine testicular block was performed on 11 males. All dogs were monitored postoperatively for a minimum of 24h and then daily until discharge. There were no clinically evident perioperative complications in heartworm-positive dogs. Purposeful pre-operative evaluation of heartworm-positive dogs while utilizing cardiovascular-sparing anesthetic protocols may allow clinicians to proceed with sterilization of hemodynamically stable heartworm-positive shelter dogs prior to heartworm treatment.
authors.affiliation: Department of Agricultural Sciences, Morehead State University, Morehead, KY, United States. Electronic address: k.peterson@moreheadstate.edu.
authors.forename: K M
authors.initials: KM
authors.lastname: Peterson
authors.affiliation: Department of Agricultural Sciences, Morehead State University, Morehead, KY, United States.
authors.forename: D E
authors.initials: DE
authors.lastname: Chappell
authors.affiliation: Department of Agricultural Sciences, Morehead State University, Morehead, KY, United States.
authors.forename: B
authors.initials: B
authors.lastname: Lewis
authors.affiliation: Department of Agricultural Sciences, Morehead State University, Morehead, KY, United States.
authors.forename: A
authors.initials: A
authors.lastname: Staton
authors.affiliation: Department of Agricultural Sciences, Morehead State University, Morehead, KY, United States.
authors.forename: E
authors.initials: E
authors.lastname: Dement
authors.affiliation: Department of Agricultural Sciences, Morehead State University, Morehead, KY, United States.
authors.forename: P E
authors.initials: PE
authors.lastname: Prater
authors.affiliation: Department of Math, Computer Science and Physics, Morehead State University, Morehead, KY, United States.
authors.forename: R A
authors.initials: RA
authors.lastname: Blanton
mesh_terms: D000758:Anesthesia / Q000662:veterinary*; D000818:Animals; D000947:Antigens, Helminth / Q000097:blood; D004184:Dirofilariasis; D004285:Dogs / Q000601:surgery; D008297:Male; D013245:Sterilization, Reproductive / Q000662:veterinary*
chemical_list: D000947:Antigens, Helminth
keywords: Anesthesia; Canine; Heartworm; Shelter medicine