title: Attenuation of ischaemic injury in the equine jejunum by administration of systemic lidocaine.
abstract: BACKGROUND
  Absorption of endotoxin across ischaemic-injured mucosa is a major cause of mortality after colic surgery. Recent studies have shown that flunixin meglumine retards mucosal repair. Systemic lidocaine has been used to treat post operative ileus, but it also has novel anti-inflammatory effects that could improve mucosal recovery after ischaemic injury.
  
  
  OBJECTIVE
  Systemic lidocaine ameliorates the deleterious negative effects of flunixin meglumine on recovery of mucosal barrier function.
  
  
  METHODS
  Horses were treated i.v. immediately before anaesthesia with either 0.9% saline 1 ml/50 kg bwt, flunixin meglumine 1 mg/kg bwt every 12 h or lidocaine 1.3 mg/kg bwt loading dose followed by 0.05 mg/kg bwt/min constant rate infusion, or both flunixin meglumine and lidocaine, with 6 horses allocated randomly to each group. Two sections of jejunum were subjected to 2 h of ischaemia by temporary occlusion of the local blood supply, via a midline celiotomy. Horses were monitored with a behavioural pain score and were subjected to euthanasia 18 h after reversal of ischaemia. Ischaemic-injured and control jejunum was mounted in Ussing chambers for measurement of transepithelial electrical resistance (TER) and permeability to lipopolysaccharide (LPS).
  
  
  RESULTS
  In ischaemic-injured jejunum TER was significantly higher in horses treated with saline, lidocaine or lidocaine and flunixin meglumine combined, compared to horses treated with flunixin meglumine. In ischaemic-injured jejunum LPS permeability was significantly increased in horses treated with flunixin meglumine alone. Behavioural pain scores did not increase significantly after surgery in horses treated with flunixin meglumine.
  
  
  CONCLUSIONS
  Treatment with systemic lidocaine ameliorated the inhibitory effects of flunixin meglumine on recovery of the mucosal barrier from ischaemic injury, when the 2 treatments were combined. The mechanism of lidocaine in improving mucosal repair has not yet been elucidated.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, NC 27606, USA.
authors.forename: V L
authors.initials: VL
authors.lastname: Cook
authors.forename: J
authors.initials: J
authors.lastname: Jones Shults
authors.forename: M
authors.initials: M
authors.lastname: McDowell
authors.forename: N B
authors.initials: NB
authors.lastname: Campbell
authors.forename: J L
authors.initials: JL
authors.lastname: Davis
authors.forename: A T
authors.initials: AT
authors.lastname: Blikslager
mesh_terms: D000779:Anesthetics, Local / Q000097:blood / Q000627:therapeutic use*; D000818:Animals; D003002:Clonixin / Q000031:analogs & derivatives / Q000494:pharmacology; D017097:Electric Impedance; D005260:Female; D006734:Horse Diseases / Q000188:drug therapy* / Q000517:prevention & control; D006736:Horses; D007262:Infusions, Intravenous / Q000662:veterinary; D007413:Intestinal Mucosa / Q000098:blood supply / Q000187:drug effects*; D007511:Ischemia / Q000188:drug therapy / Q000517:prevention & control / Q000662:veterinary*; D007583:Jejunum / Q000098:blood supply* / Q000187:drug effects / Q000378:metabolism; D008012:Lidocaine / Q000097:blood / Q000627:therapeutic use*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D010147:Pain Measurement / Q000662:veterinary; D010539:Permeability / Q000187:drug effects; D015424:Reperfusion / Q000662:veterinary; D013997:Time Factors; D046509:Tissue Culture Techniques / Q000662:veterinary
chemical_list: D000779:Anesthetics, Local; D008070:Lipopolysaccharides; C014558:flunixin meglumine; D008012:Lidocaine; D003002:Clonixin