Journal Scan: Butorphanol vs. buprenorphine for postop pain control in cats
Why they did it
A variety of pain management options are available to ease pain in our feline patients. These researchers sought to compare the efficacy of butorphanol and buprenorphine in providing postoperative pain control as assessed by a validated pain scale.
What they did
As part of a randomized and blinded study, researchers evaluated 39 healthy female cats that were admitted for routine ovariohysterectomy. The cats were divided into two groups. One group received 0.02 mg/kg of buprenorphine intramuscularly, and the other received 0.4 mg/kg of butorphanol intramuscularly.
In phase 1 (n=10), the agents were given only as part of the premedication protocol before surgery. In phase 2 (n=29), the agents were included as part of the preanesthetic protocol and were also administered at the same dose at the time of wound closure. Signs of pain were monitored in both groups beginning 20 minutes after extubation and continuing for up to 360 minutes. The same veterinary anesthesiologist performed all of the pain assessments and was blinded to the treatments administered.
What they found
Phase 1 was discontinued because nine of the 10 cats required rescue analgesia at the time of the first pain assessment. Among the cats in phase 2, pain scores for the buprenorphine group were significantly lower compared with cats receiving butorphanol (P < 0.001), and the analgesic effects appeared to last for six hours after surgery. All cats in the butorphanol group required rescue analgesia at the time of the first pain assessment, whereas none of the cats in the buprenorphine group required rescue pain control at any time point.
Butorphanol should not be used alone for management of postsurgical pain in cats undergoing ovariohysterectomy. Buprenorphine given before surgery and during wound closure is preferred to provide appropriate pain control.
Warne LN, Beths T, Holm M, et al. Evaluation of the perioperative analgesic efficacy of buprenorphine, compared with butorphanol, in cats. J Am Vet Med Assoc 2014;245(2):195-202.
Link to abstract: http://avmajournals.avma.org/doi/abs/10.2460/javma.245.2.195