title: Comparison of Morphine, Morphine-Lidocaine, and Morphine-Lidocaine-Ketamine Infusions in Dogs Using an Incision-Induced Pain Model.
abstract: We aimed to compare antinociceptive effects of IV infusions of morphine (M), morphine-lidocaine (ML), or morphine-lidocaine-ketamine (MLK) combined, in a mild-to-moderate pain model in dogs. Eighteen adult hounds were heavily sedated with IV morphine (0.2 mg/kg) and dexmedetomidine to undergo thoracic skin incisions. After reversal, dogs were randomly assigned to receive loading doses of lidocaine and ketamine (MLK), lidocaine and saline (ML), or equivalent volume of saline (M), followed by 18 hr constant infusions of morphine (0.12 mg/kg/hr), lidocaine (3 mg/kg/hr) and ketamine (0.6 mg/kg/hr); morphine (0.12 mg/kg/hr) and lidocaine (3 mg/kg/hr); or morphine (0.12 mg/kg/hr), respectively. Pain was assessed with Short Form Glasgow Composite Measure Pain Scale and mechanical nociception with von Frey filaments (VFFS). Data were analyzed with linear mixed model on ranks. Independently of treatment, Short Form Glasgow Composite Measure Pain Scale was significantly higher than baseline for 24 hr (p < .0001), while VFFS was significantly lower than baseline for 48 hr post-recovery (p < .0001), with no difference between MLK and M groups. The ML group recorded significantly lower VFFS (p = .02) than the M group for the entire study. In conclusion, there was no significant analgesic difference between MLK and M alone.
authors.forename: Ludovica
authors.initials: L
authors.lastname: Chiavaccini
authors.affiliation: From the Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, California (L.C.); and College of Veterinary Medicine, Department of Clinical Sciences, Mississippi State, Starkville, Mississippi (A.K.C., R.E.M.).
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Claude
authors.affiliation: From the Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, California (L.C.); and College of Veterinary Medicine, Department of Clinical Sciences, Mississippi State, Starkville, Mississippi (A.K.C., R.E.M.).
authors.forename: Robert E
authors.initials: RE
authors.lastname: Meyer
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000209:etiology / Q000517:prevention & control*; D004285:Dogs; D005260:Female; D007649:Ketamine / Q000008:administration & dosage / Q000494:pharmacology*; D008012:Lidocaine / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D010146:Pain / Q000517:prevention & control / Q000662:veterinary*; D000072836:Surgical Wound / Q000662:veterinary
chemical_list: D007649:Ketamine; D009020:Morphine; D008012:Lidocaine