title: Contemporary use of acepromazine in the anaesthetic management of male horses and ponies: a retrospective study and opinion poll.
abstract: BACKGROUND
  Current use of acepromazine in the anaesthetic management of male horses and ponies and associated risks are largely unknown.
  
  
  OBJECTIVE
  To explore anaesthetic acepromazine use and related adverse effects in the male horse.
  
  
  METHODS
  Of 8533 anaesthetised horses and ponies medical records of male animals treated perianaesthetically with acepromazine were reviewed. Demographic data, time and dose of acepromazine administration, co-administered drugs, quality of induction and recovery from anaesthesia, arterial blood pressures, and occurrence of penile dysfunction were recorded. Practising ACVA and ECVAA diplomates were polled on the use of acepromazine and its effects on blood pressure and penile dysfunction in the equine.
  
  
  RESULTS
  Of all animals, 12% females and 11% males (n=575 including 42% stallions) received perianaesthetic acepromazine, predominantly for premedication. Anaesthetic induction was smooth in 566 animals. Lowest mean arterial pressures averaged 65±9 mmHg. Recovery was good or very good in 70% of all animals and 74% stood after 1-2 attempts. In 14 horses (2.4%; 7 stallions, 7 geldings), penile prolapse occurred for 0.5-4 h and in one stallion (0.2%) for >12 but <18 h post recovery. Most surveyed anaesthesiologists use acepromazine in stallions (occasionally 63%; frequently 17%) but more frequently in geldings (occasionally 34%; frequently 59%) and mares (occasionally 38%; frequently 59%), primarily for premedication with other sedatives and analgesics. Persistent intraoperative hypotension was not frequently reported. Only 5% of surveyed anaesthesiologists recall penile prolapse post acepromazine administration lasting for >12 h and only one recalls 3 cases of irreversible penile prolapse in 20 years of anaesthesia practice.
  
  
  CONCLUSIONS
  The extremely low risk of permanent penile dysfunction (≤1 in 10,000 cases) does not justify more restricted use of acepromazine in the intact male vs. geldings and mares.
authors.affiliation: Department of Clinical Studies, New Bolton Center, University of Pennsylvania, School of Veterinary Medicine, PA, USA. driessen@vet.upenn.edu
authors.forename: B
authors.initials: B
authors.lastname: Driessen
authors.forename: L
authors.initials: L
authors.lastname: Zarucco
authors.forename: B
authors.initials: B
authors.lastname: Kalir
authors.forename: L
authors.initials: L
authors.lastname: Bertolotti
mesh_terms: D000075:Acepromazine / Q000009:adverse effects*; D000758:Anesthesia / Q000662:veterinary*; D000818:Animals; D003625:Data Collection; D005260:Female; D006734:Horse Diseases / Q000139:chemically induced*; D006736:Horses; D006993:Hypnotics and Sedatives / Q000009:adverse effects*; D007022:Hypotension; D008297:Male; D010409:Penile Diseases / Q000139:chemically induced / Q000662:veterinary*; D012189:Retrospective Studies; D012727:Sex Characteristics; D011795:Surveys and Questionnaires
chemical_list: D006993:Hypnotics and Sedatives; D000075:Acepromazine