title: Evaluation of the isoflurane-sparing effects of lidocaine infusion during umbilical surgery in calves.
abstract: OBJECTIVE
  To evaluate the isoflurane-sparing effects of lidocaine administered by constant rate infusion (CRI) during umbilical surgery in calves.
  
  
  METHODS
  Randomized 'blinded' prospective clinical study.
  
  
  METHODS
  Thirty calves (mean 4.7 ± SD 2.5 weeks old) undergoing umbilical surgery.
  
  
  METHODS
  After premedication with xylazine (0.1 mg kg(-1) , IM), anaesthesia was induced with ketamine (4 mg kg(-1) , IV) and maintained with isoflurane in O(2) administered through a circle breathing system. The calves were assigned randomly to receive a bolus of 2 mg kg(-1) lidocaine IV after induction of anaesthesia, followed by CRI of 50 μg kg(-1) minute(-1) (group L, n=15) or a bolus and CRI of 0.9% sodium chloride (NaCl, group S, n=15). End-tidal isoflurane was adjusted to achieve adequate depth of anaesthesia. Heart rate, direct arterial blood pressure and body temperature were measured intraoperatively. Groups were compared by t- tests, anova or Mann-Whitney rank sum test as appropriate.
  
  
  RESULTS
  The end-tidal concentration of isoflurane (median, IQR) was significantly lower in group L [1.0% (0.94-1.1)] compared to group S [1.2% (1.1-1.5)], indicating a 16.7% reduction in anaesthetic requirement during lidocaine CRI. Cardiopulmonary parameters and recovery times did not differ significantly between groups.
  
  
  CONCLUSIONS
  Lidocaine CRI may be used as a supplement to inhalation anaesthesia during umbilical surgery in calves in countries where such a protocol would be within the legal requirements for veterinary use in food animals. This study did not show any measurable benefit to the calves other than a reduction in isoflurane requirement.
authors.affiliation: Department of Veterinary Clinical Studies, School of Veterinary Medicine, Shiraz University, Shiraz, Iran.
authors.forename: Nasser
authors.initials: N
authors.lastname: Vesal
authors.forename: Claudia
authors.initials: C
authors.lastname: Spadavecchia
authors.forename: Adrian
authors.initials: A
authors.lastname: Steiner
authors.forename: Franziska
authors.initials: F
authors.lastname: Kirscher
authors.forename: Olivier L
authors.initials: OL
authors.lastname: Levionnois
mesh_terms: D000768:Anesthesia, General / Q000662:veterinary*; D000771:Anesthesia, Intravenous / Q000662:veterinary*; D000818:Animals; D001784:Blood Gas Analysis / Q000662:veterinary; D001794:Blood Pressure / Q000187:drug effects; D002417:Cattle / Q000601:surgery; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D007275:Injections, Intravenous / Q000662:veterinary; D007441:Intubation, Gastrointestinal / Q000662:veterinary; D007530:Isoflurane / Q000008:administration & dosage*; D008012:Lidocaine / Q000008:administration & dosage; D008297:Male; D019060:Minimally Invasive Surgical Procedures / Q000662:veterinary*; D010092:Oximetry / Q000662:veterinary; D012121:Respiration, Artificial / Q000662:veterinary; D014472:Umbilicus / Q000601:surgery
chemical_list: D008012:Lidocaine; D007530:Isoflurane