title: Prevalence, outcome and risk factors for postoperative pyothorax in 232 dogs undergoing thoracic surgery.
abstract: OBJECTIVE
  To determine the prevalence, outcome and risk factors for postoperative pyothorax in dogs undergoing thoracic surgery.
  
  
  METHODS
  Case records were reviewed retrospectively to identify dogs with post thoracic surgery pyothorax, defined as septic neutrophilic inflammation within the pleural space based on cytology and/or a positive bacterial culture of pleural fluid. Those identified were reviewed for potential risk factors for postoperative pyothorax based on biological plausibility and previously published data. These potential risk factors were explored by multivariable logistic regression.
  
  
  RESULTS
  Of 232 dogs undergoing thoracic surgery, 15 (6.5%) dogs developed pyothorax. Bacteria cultured included methicillin-resistant Staphylococcus aureus and multi-resistant Escherichia coli. Of these dogs, six died, four were euthanased and five were treated successfully. A diagnosis of idiopathic chylothorax [Odds Ratio (OR)=12.5, 95% Confidence Interval (CI)=2.7-58.5, P=0.001], preoperative intrathoracic biopsy (OR=14.3, 95% CI=1.7-118.7, P=0.014) and preoperative thoracocentesis (OR=11.2, 95% CI=1.6-78.2, P=0.015) were identified as independent risk factors for development of postoperative pyothorax.
  
  
  CONCLUSIONS
  Idiopathic chylothorax, intrathoracic biopsy and prior thoracocentesis are independent risk factors for postoperative pyothorax, which was associated with a 67% mortality rate.
authors.affiliation: School of Veterinary Sciences, University of Bristol, Langford, Bristol BS40 5DU.
authors.forename: L B
authors.initials: LB
authors.lastname: Meakin
authors.forename: L K
authors.initials: LK
authors.lastname: Salonen
authors.forename: S J
authors.initials: SJ
authors.lastname: Baines
authors.forename: D J
authors.initials: DJ
authors.lastname: Brockman
authors.forename: S P
authors.initials: SP
authors.lastname: Gregory
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Halfacree
authors.forename: V J
authors.initials: VJ
authors.lastname: Lipscomb
authors.forename: K C
authors.initials: KC
authors.lastname: Lee
mesh_terms: D000818:Animals; D001706:Biopsy / Q000009:adverse effects / Q000662:veterinary; D002916:Chylothorax / Q000150:complications / Q000601:surgery / Q000662:veterinary; D004283:Dog Diseases / Q000453:epidemiology / Q000209:etiology*; D004285:Dogs; D016724:Empyema, Pleural / Q000453:epidemiology / Q000209:etiology / Q000662:veterinary*; D005260:Female; D008297:Male; D011183:Postoperative Complications / Q000453:epidemiology / Q000662:veterinary; D015995:Prevalence; D012307:Risk Factors; D016019:Survival Analysis; D019616:Thoracic Surgical Procedures / Q000009:adverse effects / Q000662:veterinary*; D016896:Treatment Outcome