title: Retrospective clinical evaluation of ultrasound guided transverse abdominis plane block in dogs undergoing mastectomy.
abstract: METHODS
  Eleven female dogs of different breeds undergoing unilateral radical (n = 7) or regional abdominal mastectomy (n = 4) received an ultrasound guided transverse abdominis plane block (TAP-block).
  
  
  METHODS
  Subjects showed single or multiple mammary tumours. Serum biochemistry, CBC and electrocardiogram were unremarkable. Eight animals were classified as ASA physical status II and 3 as ASA III.
  
  
  RESULTS
  Dogs were premedicated with methadone [0.1 or 0.2 mg kg(-1) intravenously (IV) or intramuscularly respectively] or fentanyl (2.5 μg kg(-1) IV). Anaesthesia was induced with propofol and maintained with isoflurane or sevoflurane. Unilateral ultrasound guided TAP blocks were performed in the caudal and cranial abdomen with bupivacaine 0.25% (0.3 to 0.35 mL kg(-1) ). Intercostal nerve blocks (T4 to T11 ) with bupivacaine 0.25% (0.013 to 0.04 mL kg(-1) ) completed the blocked area in dogs undergoing radical mastectomy.
  
  
  RESULTS
  The median (range) of end-expired isoflurane and sevoflurane necessary to maintain anaesthesia was 1.15 (1.07-1.22) and 2.07 (2.05-2.2) vol% respectively. A single administration of fentanyl (2.5 μg kg(-1) , IV) was administered to control nociception (defined as an increased heart rate or mean arterial blood pressure above 20% of the pre-incisional value) in four of 11 dogs. All dogs received carprofen (2 mg kg(-1) subcutaneously) at the end of surgery. Post-operative pain, assessed for 120 minutes using the short form of Glasgow Composite Pain Scale (0-24), was always lower than 3. No rescue analgesia (allowed by the protocol) was required in this time.
  
  
  CONCLUSIONS
  Transverse abdominis plane block combined with intercostal nerve blocks may be useful to produce intraoperative anti-nociception and short term post-operative analgesia in dogs undergoing unilateral mastectomy.
authors.affiliation: Department of Veterinary Sciences, Veterinary Teaching Hospital "Mario Modenato", University of Pisa, San Piero a Grado, Italy.
authors.forename: Diego A
authors.initials: DA
authors.lastname: Portela
authors.forename: Marta
authors.initials: M
authors.lastname: Romano
authors.forename: Angela
authors.initials: A
authors.lastname: Briganti
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D002045:Bupivacaine / Q000008:administration & dosage / Q000494:pharmacology*; D004283:Dog Diseases / Q000601:surgery*; D004285:Dogs; D005260:Female; D015674:Mammary Neoplasms, Animal / Q000601:surgery*; D008408:Mastectomy / Q000662:veterinary*; D009407:Nerve Block / Q000379:methods / Q000662:veterinary*; D010149:Postoperative Pain / Q000517:prevention & control / Q000662:veterinary; D012189:Retrospective Studies; D018084:Ultrasonography, Interventional / Q000662:veterinary*
chemical_list: D000779:Anesthetics, Local; D002045:Bupivacaine
keywords: TAP block; cancer pain; dog; mastectomy; regional anaesthesia; ultrasound