HOW-TO SESSION: FIELD ANESTHESIA AND PAIN MANAGEMENT How to Provide Pain Relief for Laminitis in the Field Alonso Guedes, DVM, MS, PhD Author’s address: University of California, Davis, One Shields Avenue, Davis, CA 95616; e-mail: [email protected]. © 2013 AAEP. 1. Introduction characterized by hyperalgesia (ie, exaggerated re- sponse to a painful stimulus) and allodynia (ie, pain Laminitis is an extremely painful condition with 6,13–15 still incompletely understood pathophysiology.1–3 response to a normally nonpainful stimulus). All too often, the uncontainable severe pain associ- The goal of this report is to present techniques tar- ated with the disease is the single most common geting such pathologic pain states that can be used reason for euthanasia of laminitic horses. Treat- to manage pain and suffering in horses with ment is frequently unfinished because owners and laminitis. health providers feel forced to end the extreme pain and suffering by ending the life of the afflicted ani- 2. Recommended Agents and Routes of mal. More positive treatment results could be ob- Administration tained if pain and suffering could be successfully Tramadol tablets can be crushed into powder, mixed modulated.4 Non-steroidal anti-inflammatory with syrup or molasses, and administered orally at a drugs (NSAIDs) such as flunixin meglumine and dose of 5 mg/kg q 12 hours.6 phenylbutazone have long been and still remain the Ketamine can be administered intravenously as a primary pharmacologic agents used to treat pain constant rate infusion at a dose of 0.6 mg/kg per and inflammation in horses with laminitis.5 hour for 6 hours/day for 3 to 5 days (or longer as 6 Tramadol is emerging as an additional option to- needed) through a syringe pump, or it can be di- ward providing multimodal analgesia in equine luted in 0.9% saline and dripped by gravity. Alter- laminitis,6 and its efficacy has been well established natively, it can be administered intramuscularly at 14 in neuropathic and inflammatory pain states.7–10 0.5 mg/kg q 6 hours. Because it is now known that pain associated with Gabapentin can be administered orally at doses laminitis has both inflammatory and neuropathic ranging from 2.5 to 20 mg/kg q 8 hours, q 12 hours, 13–15 components,11,12 targeted multimodal analgesic or q 24 hours, as needed. therapies probably will be necessary for effective pain modulation. Drugs such as ketamine and ga- 3. Evidence of Efficacy bapentin may be very beneficial in modulating neu- When administered alone, tramadol was shown to ropathic pain as well as pathologic pain states produce significant initial improvement (3 of 7 days) NOTES AAEP PROCEEDINGS ր Vol. 59 ր 2013 467 HOW-TO SESSION: FIELD ANESTHESIA AND PAIN MANAGEMENT in off-loading frequency in analgesic-naive horses mechanistic-based approach in providing multi- with pain caused by chronic laminitis.6 In this modal pain management in horses with laminitis. same study, ketamine administered intravenously for the first 3 days of treatment significantly im- References proved off-loading frequency and forelimb load dur- 1. Hood DM. The pathophysiology of developmental and acute ing (7 of 7 days) and after (3 days) tramadol therapy. laminitis. Vet Clin North Am Equine Pract 1999;15:321– 343. Tramadol and ketamine had a modulatory role in 2. Hood DM, Grosenbaugh DA, Mostafa MB, et al. 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