Evaluation of soluble epoxide hydrolase inhibition in experimentally induced radiocarpal synovitis in horses

Methods: Twelve dogs scheduled for unilateral TPLO surgery were randomly assigned to one of two groups, systemic analgesia alone (SA) or regional analgesia (lumbar plexus and sciatic nerve block with ropivacaine) (RA). The anesthetic protocol for all dogs was hydromorphone, propofol and isoflurane. The cost to manage anesthesia and postoperative period were compared using Mann-Whitney U test. Statistical difference was considered when p < 0.05. Results: The cost for anesthesia, analgesia and care was higher in the SA group. The SA group required higher isoflurane vaporizer settings, rescue analgesia during surgery (fentanyl) and sedation and analgesia during the recovery period. In addition, 4/5 dogs in the SA group developed hypotension and 3 required intensive treatment. In the RA group, 3/7 dogs developed hypotension but none required intensive treatment. In the recovery period, 2/5 dogs in the SA group required additional bandage change or nursing care. The duration of anesthesia was similar between groups (174 minutes (SA) versus 179 minutes (RA); p1⁄4 0.7). The cost to maintain anesthesia, analgesia and care intraand postoperatively per dog was $34156 for the SA group and $26-55 for the RA group. Conclusion: The preliminary results suggest that the use of ultrasound guided lumbar plexus and sciatic nerve blocks can decrease the cost of anesthesia and postoperative care while improving pain management for TPLO surgery in dogs. http://dx.doi.org/10.1016/j.vaa.2016.12.053 Cardiovascular effects of carbon dioxide insufflation for thoracoscopy in cats P Pascoe, P Mayhew, J Mitchell & M Steffey Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA Introduction: This study compared the cardiovascular effects of 0, 3 and 5 mmHg using CO2 insufflation. Methods: Six healthy adult cats (6.15±0.41 kg)were used with random assignment of treatment order. Anesthesia was induced using isoflurane in oxygen, the cats were orotracheally intubated and maintained on isoflurane in 50% oxygen using IPPV and a nonrebreathing circuit. Cats were instrumented with peripheral venous, pulmonary and femoral arterial catheters. End-tidal CO2, isoflurane, peak inspiratory pressure (PIP) and PEEP values were measured using Veterinary Anaesthesia and Analgesia, 44, 195.e1e195.e13 a calibrated multiparameter monitor. Ventilation was adjusted to maintain PE'CO2. All variables were measured 30 minutes after initiating each treatment. Intrathoracic pressure was returned to 0 mmHg for 10 minutes before the next treatment. Variables were compared using a one-way analysis of variance for repeated measures with a post-hoc Tukey test. Results: Maintenance of normocapnia required significant increases in fR (13± 4 to 17± 4 and 20± 5 bpm), PIP (8± 1 to 16± 3 and 19± 2 cmH2O) and PEEP (3± 1 to 5 ± 1 and 6± 2 cmH2O) for 0, 3 and 5 mmHg, respectively. Cardiovascular variables were all similar except CVP, which increased (7 ± 2 to 10± 1 and 11± 1 mmHg for 0, 3 and 5 mmHg) with CO2 insufflation. There were no statistically significant differences between 3 and 5 mmHg. Conclusion: In healthy cats, CO2 insufflation for thoracoscopy had minimal effect on the cardiovascular system despite the need for increased ventilation. http://dx.doi.org/10.1016/j.vaa.2016.12.052 Evaluation of soluble epoxide hydrolase inhibition in experimentally induced radiocarpal synovitis in horses A Guedes, F Aristizabal, A Sole, A Adedeji, R Brosnan, H Knych, S-H Hwang, C Morisseau & B Hammock University of Minnesota, St Paul, MN, USA University of California Davis, Davis, CA, USA The University of Sydney, Sydney, Australia Midwestern University, Glendale, AZ, USA Introduction: Epoxy fatty acids stabilization via soluble epoxide hydrolase (sEH) inhibition might modulate nociception in horses with painful joint conditions. Goals were to determine the pharmacokinetics, antinociceptive and anti-inflammatory effects of the sEH inhibitor t-TUCB in horses with lipopolysaccharide (LPS)-induced radiocarpal synovitis. Methods: Seven healthy mares were administered t-TUCB at 0 (control), 0.03, 0.1, 0.3 and 1 mg kg IV concurrently with LPS injection in a Latin square design. At baseline, then at 2, 4, 8, 12, 24, 36 and 48 hours after t-TUCB, two individuals assigned lameness (American Association of Equine Practitioners; 0-5) and pain scores (visual analog scale; 01⁄4 no pain, 1001⁄4 extreme pain). Clinical and laboratory evaluations and determination of plasma t-TUCB concentrations were performed. Synovial fluid (SF) was collected bilaterally at baseline, 12 and 24 hours