Investigating alternatives to opioids for dogs in pain

Opioids are among the most effective pain relievers in dogs and cats, but amid the U.S. opioid crisis it has become much more difficult for animal hospitals to access these drugs. This, coupled with the potential for abuse of opioids by pet owners or others, makes it increasingly imperative that veterinarians pursue alternatives.

In one promising approach, the Henry and Lois Foster Hospital for Small Animals is now enrolling for a clinical study to compare options for dogs needing back surgery. The research team hopes to demonstrate that postsurgical opioid-sparing techniques are just as effective as the opioid-dependent one predominantly used in veterinary practice.

"We decided to focus on dogs undergoing spinal surgery because veterinarians are already using different pain protocols in these patients," said Ane Uriarte, a neurosurgeon and neurologist at the Foster Hospital, "but there have been no studies on which ones work better than others."

Uriarte and neurology resident Miranda Gallo, V15, VG15, devised a plan to compare three pain-management approaches with the help of former anesthesia resident Rebecca Reader, V13, and anesthesiologist Emily McCobb, V00, VG02. Each dog in the study will be randomly assigned to one of the three plans, all of which are effective at controlling pain after back surgery. (The dogs also will be frequently assessed for pain so they can receive additional medication if necessary.)

The first protocol is the traditional opioid protocol, the second uses an opioid intermittently, and the last avoids opioids altogether. "Our primary objective is to compare the effectiveness of the three protocols," Uriarte said. "We have seen the two opioid-sparing approaches work at least as well as the industry standard, but we want to provide the data that proves that."

The researchers' second, more-ambitious objective is to uncover whether using fewer or no opioids after surgery results in shorter hospital stays for pets. There has been a growing focus in human medicine on "enhanced recovery after surgery," Uriarte said, to assess how factors like eating, walking, and hydration affect a hospital patient's stay and subsequent recovery. "In human medicine, we have seen evidence that postsurgical opioids can prolong hospital stays," Uriarte said. "So it makes sense to look at alternatives."

McCobb agreed. "Most patients will get at least one dose of an opioid during an operation as these medications are still the gold standard for surgical pain," said the Foster Hospital anesthesiologist. "But given that opioids are broad-spectrum agents with a myriad of effects on all body systems, it is best for patient care to minimize the dose and duration of treatment."

The clinical study will build on efforts at Cummings School and throughout veterinary medicine to respond to the opioid crisis. In 2017, the Massachusetts Veterinary Medical Association, the teen substance-abuse prevention group Decisions at Every Turn, and Cummings School launched a public-education campaign targeted toward pet owners and veterinarians.