title: Post anaesthetic colic in horses: a preventable complication?
abstract: BACKGROUND
  There is little information on the prevalence of, and risk factors associated with, post anaesthetic colic (PAC) in horses undergoing nonabdominal operations.
  
  
  OBJECTIVE
  To undertake the first prospective study of prevalence of PAC and identify risk factors in its development in nonabdominal procedures.
  
  
  METHODS
  A multicentre prospective case-control study was conducted, on every horse undergoing anaesthesia for a nonabdominal procedure between April 2004 and June 2005. Colic cases were defined as any horse with recognised signs of abdominal pain within 72 h of general anaesthesia that could not be attributed to any concurrent disease. Five control horses per case were selected randomly from the study population at all hospitals. Multivariable logistic regression analysis was used to examine the relationship between predictor variables and the risk of developing PAC.
  
  
  RESULTS
  The estimated mean prevalence of PAC in the study population was 5.2% (95% CI, 2.8, 8.0). However, the prevalence of colic varied between each centre. The most commonly diagnosed cause of colic was impaction. Multivariable analyses showed that the centre involved and the type of surgery performed were associated with an increased risk of PAC. Preoperative food deprivation and the use of opioid drugs were confounding factors.
  
  
  CONCLUSIONS
  Prevalence of PAC varied significantly between the 4 hospitals studied; there may be hospital-related covariates that account for this. The type of surgery performed influenced the risk of PAC.
  
  
  CONCLUSIONS
  Identifying the risk factors for PAC is a prerequisite for its prevention. This study indicates horses at increased risk of PAC that might benefit from a more critical evaluation of post anaesthetic gastrointestinal function and/or the provision of preventative measures. Further investigation is required to explain the variation in prevalence of PAC between centres.
authors.affiliation: Institutes of Evolution, Immunology and Infection Research, University of Edinburgh, UK.
authors.forename: J M
authors.initials: JM
authors.lastname: Senior
authors.forename: G L
authors.initials: GL
authors.lastname: Pinchbeck
authors.forename: R
authors.initials: R
authors.lastname: Allister
authors.forename: A H A
authors.initials: AH
authors.lastname: Dugdale
authors.forename: L
authors.initials: L
authors.lastname: Clark
authors.forename: R E
authors.initials: RE
authors.lastname: Clutton
authors.forename: K
authors.initials: K
authors.lastname: Coumbe
authors.forename: S
authors.initials: S
authors.lastname: Dyson
authors.forename: P D
authors.initials: PD
authors.lastname: Clegg
mesh_terms: D000758:Anesthesia / Q000009:adverse effects / Q000662:veterinary*; D000818:Animals; D016022:Case-Control Studies; D003085:Colic / Q000139:chemically induced / Q000453:epidemiology / Q000517:prevention & control / Q000662:veterinary*; D016001:Confidence Intervals; D005215:Fasting; D005244:Fecal Impaction / Q000150:complications / Q000453:epidemiology / Q000662:veterinary; D006734:Horse Diseases / Q000139:chemically induced / Q000453:epidemiology* / Q000517:prevention & control; D006736:Horses; D016015:Logistic Models; D015999:Multivariate Analysis; D016017:Odds Ratio; D011183:Postoperative Complications / Q000139:chemically induced / Q000453:epidemiology / Q000517:prevention & control / Q000662:veterinary*; D011237:Predictive Value of Tests; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors