Recognition and Treatment of Pain:  Recognizing pain in animals is difficult.  Some of he signs of pain are consistent between humans and animals, but many are not.  The following chart was developed to provide assistance with determining when an animal requires intervention exceeding the current plan. 

Scores >7 will require intervention, which may include additional doses of fentanyl or use of an anxiolytic such as diazepam.  The use of buprenorphine for ‘breakthrough’ pain is controversial.^1,2,3   Naloxone should be on hand to counteract adverse side effects of opiate overdose related to bradycardia and respiratory depression. 

References:

1. Kirk’s Current Veterinary Therapy, Acute Pain Management; Hendrix, Paul, Hansen, Bernie, “Additionally it [buprenorphine] binds avidly to mu receptors and may be difficult to displace with the use of an antagonist or another mu-agonist.

2. Buprenorphine: a reappraisal of its antinociceptive effects and therapeutic use in alleviating post-operative pain in animals, Laboratory Animals 36:322-343, 2002; Roughan, J., Flecknell, P. “It would be expected from the pharmacology of these agents [buprenorphine and butorphanol] that they may antagonize the effects of a subsequently administered pure mu agonist such as morphine.”

3. Buprenorphine blocks epsilon- and micro-opiod receptor mediated antinociception in the mouse.  Mizoguchi et al.  J of Pharmacol Exp Ther. 306(1):394-400 2003.