How Pain Management In Small Animals Has Grown

To better treat your dog and cat, understanding pain and pain management and learning more on how to treat pain is crucial.

For Duncan X. Lascelles, a professor of small animal surgery at North Carolina State University College of Veterinary Medicine, understanding pain is the cornerstone to building a better foundation for treating it in small animals.

And Lascelles, BVSc, Ph.D., Dipl. ACVS and ECVS, is encouraged by the improvements in recognizing pain being made in veterinary medicine and at institutions like NC State.

"I think the first breakthrough I see is the increasing amount of information regarding pain assessment," Lascelles said. "We're seeing more tools for practitioners and also for clinical researchers."

Better assessment tools enable practitioners to know whether non-drug therapies are working, and they enable practitioners dealing with pain management to better monitor the efficacy of their treatments

Lascelles suggested that practitioners dealing with perioperative pain in dogs use the Glasgow Composite Measure Pain Scale Short Form. The same group that came out with the scale is soon to publish the feline version, Lascelles noted.

For chronic pain in dogs, Lascelles likes the University of Pennsylvania's Canine Brief Pain Inventory and the Helsinki Chronic Pain Index. There are also a number of new tools that can help pet owners measure chronic pain, or can assist veterinary technicians with measuring acute pain, Lascelles said.

Lascelles would like to see someone develop an assessment to provide an objective pain measurement in the home or postoperative environments.

"There's a lot of work to be done, but it's a rapidly changing area," he said.

Holy Grail Of Small Animal Pain Management

The "holy grail" of pain management, said Robin Downing, DVM, "is an objective, reliable and consistent way to find, assess and measure pain—both acute and chronic. This is true on the human side of pain management as well.

"It would be very liberating to uncover a true 'pain-ometer,'" she said.

Downing, owner of the Downing Center LLC for Animal Pain Management in Windsor, Colo., agreed that pain assessment tools have improved, they cannot be the only way to assess pain.

"It is critical to understand that we cannot assess pain in pets simply by observing and watching them," Downing said. "We must interact with them, including palpation of their tissues, in order to determine if they are painful as well as where they are painful, and how much pain they are experiencing. It is equally critical to recognize the limitations of our pain assessment tools and techniques, but not to allow those limitations to immobilize us and prevent us from doing the best we can for our patients."

The current challenge for creating and adapting these assessment tools is standardizing assessment, Downing said.

At that point practitioners can move to a paradigm in which all patients receive a pain assessment any time they are presented to the veterinary practice, she added.

"We know that pain, just like cancer and many other diseases, is best managed when it is detected early," Downing said.  "Assessing every patient every time provides the practitioner with a clear sense of what normal (no pain) looks like and feels like. That dramatically increases the probability that we will find painful patients early in the course of their pain, allowing for earlier—and often more effective—intervention."

Improvements In Pain Management For Dogs And Cats

Mary Ellen Goldberg, LVT, CVT, director at large and executive secretary of the International Veterinary Academy of Pain Management, has been a veterinary medical technician since 1976.

"In that time period, I have seen veterinary pain management go from basically non-existent to improving every single month through education of those in veterinary practice," Goldberg said.

Goldberg credited the numerous meetings, conferences, educational webinars, articles published in journals, and private educational seminars for improving knowledge of veterinary pain management.

Goldberg said the consequences of untreated pain are many.

  • Pain produces a catabolic state, which may lead to wasting;
  • Pain suppresses the immune response, predisposing a patient to infection and increasing hospitalization time and cost;
  • Pain promotes inflammation, which delays wound healing;
  • Anesthetic risk is increased because higher doses of anesthetic drugs are required to maintain a stable plane of anesthesia;
  • Pain causes patient suffering, which is also stressful for owners and caregivers.

Goldberg said there are no legitimate reasons for a veterinary patient to  suffer from unalleviated pain. She cited the American Veterinary Medical Association's policy:

"Animal pain and suffering are clinically important conditions that adversely affect an animal's quality of life. Drugs, techniques or husbandry methods should be used to prevent, minimize and relieve pain in animals experiencing or expected to experience pain. Protocols must be tailored to individual animals and should be based, in part, on the species, breed, age, procedure performed, degree of tissue trauma, individual behavioral characteristics, degree of pain and health status of the animal."

Treating Pain In Small Animals

Lascelles sees more practitioners embracing the spectrum of treatment options, sometimes using several in unison, such as using local anesthetics, opioids and non-steroidal anti-inflammatories to manage pain.

A multimodal approach can also include nondrug therapies, like cold therapy, bandaging and nursing care, Lascelles added.

Even a combination of pain drugs and non-drug techniques can be employed on the same patient with great success, like using an NSAID, monitoring the diet with anti-inflammatory considerations, and prescribed exercise, he said.

"The key is to not rely on any one modality or drug but to combine different types of drugs and modalities," Lascelles said.

Such an approach can reduce side effects and increase efficacies at the same time, he added.

Pain-treating drugs Goldberg sees being used more include OroCAM (meloxicam), the newer Transmucosal Oral Spray made by Abbott Animal Health indicated for the control of pain and inflammation associated with osteoarthritis in dogs.

"It is administered via a gentle mist onto the dog's gums or inner cheek, where it is rapidly absorbed into the blood stream," Goldberg said.

Elanco Companion Animal Health released a transdermal fentanyl solution called Recuvyra that provides post-operative pain control with a new transdermal delivery, she added.

"A single dose (1.2 mg/lb) applied to the dorsal scapular area of dogs prior to surgery is designed to control pain for four days," Goldberg said. "Elanco says its new-patented drug delivery technology will reduce the need for home administration of analgesics, misuse and abuse of potent drugs and concerns with client compliance."

Better Understanding Of The Nervous System Equals Better Pain Management

The biggest breakthrough in pain management and treatment Downing has seen in her years in the field is a better understanding of how the nervous system works.

Pain runs a spectrum—from adaptive (good) pain to maladaptive (bad) pain, Downing said.

"The implication of not providing appropriate protection from the pain experience in an acute setting can allow adaptive pain to morph into maladaptive pain—leading to central and peripheral sensitization, or windup," she said. "Likewise, once maladaptive pain is in place, we need to utilize a multimodal approach to pain management in both the acute and chronic pain setting."

The key to success is to provide targeted therapy, identify specific targets in the body that influence pain, and then use specific tools to hit those targets.

"For instance, inflammation is a target, and NSAIDs hit that target," Downing said. "Chronic maladaptive pain, we now know, is modulated by the dorsal horn of the spinal cord, providing us yet another target for managing pain – specifically, neuromodulatory agents like gabapentin."

Downing is conducting a retrospective study on the use of gabapentin for the maladaptive pain seen with chronic osteoarthritis in dogs.

"We are reviewing well over 100 cases," she said.

Laser Therapy

Another pain treatment that veterinarians are turning to is laser therapy, noted Laurie McCauley, DVM, medical director of TOPS Veterinary Rehabilitation in Grayslake, Ill.

"Laser therapy has also become more mainstream as part of the multimodal pain plan," she said.

Dr. McCauley, who is certified in veterinary acupuncture, chiropractic and rehabilitation, said veterinarians are using laser therapy post-surgery, for injuries, dental issues, skin issues and to help manage pain in arthritic patients.

She thinks laser therapy usage will continue to grow.

"Laser definitely will play a larger role in pain management in the future," McCauley said. "I have had multiple clients who are in the medical profession see what it did for their pets who then purchased a unit for their practice. They all report excellent results, and with the added benefit that there are none of the side effects seen with drugs, this modality will continue to grow in popularity."

McCauley noted the increase in research being conducted in veterinary schools with pets, as well as with different lasers—various wavelengths, frequencies and intensities.

As the outcomes of that research become known, practitioners who use laser therapy will be better able to hone in on the best protocols for each situation," McCauley said. "In the past, most research had been done with humans, chickens, rats, mice and petri dishes."

Education On Pain Management

Educating clients is also important, Goldberg said, adding that the veterinarian and the entire staff must be on board.

Clients should be made aware of behaviors that can occur if the animal is on too high a dosage or too low a dosage of specific drugs.

Goldberg suggests creating client educational materials like handouts and checklists to teach pet owners about chronic pain in pets and how to recognize it, and owners should go home with written and verbal instructions on how to give medications and transition to any new diet.

Suggestions that can be given to clients can include modifying a pet's environment to make it more comfortable, like providing warm, soft bedding.

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