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Pain Assessment

Due to their evolution as a solitary, self-dependent species that needs to protect territory and resources, cats are masters at hiding illness and geniuses at concealing pain. Signs of pain in cats are often extremely subtle, especially in comparison to dogs. As a result, clients are often incorrect in their expectations of what they will observe if their cat is in pain. While we can safely predict that many medical procedures and all surgeries performed on cats cause pain, we are much less effective at predicting the pain that cats might be experiencing from arthritis, dental disease, urogenital disease, skin disease, and a host of other sources of pain. The clinician caring for cats must be able to identify historical changes suggestive of pain through careful questioning, as well as identify pain during outpatient visits through careful observation. It is important to note that many cats being labelled as ‘fractious’ or ‘bad-actors’ are often acting in a defensive mode towards clinic staff because they are in fact in pain. Looking at these patients from the perspective of pain management, we can be highly successful in reducing uncooperative behaviour in our feline patients.

Identifying Pain: Outpatient Assessment

Pain assessment should be part of every consultation and physical examination, regardless of the reason for the visit. Cats in all age groups should be assessed for evidence of pain.

Obtaining a clinical history with an aim to identify pain in our feline patients can be challenging. The clinical signs of chronic pain may be even harder to discern, as the patient has learned to cope with the pain, often developing alternative strategies for pursuit of daily activities. Most clients expect specific and obvious signs of pain. They may expect painful cats to vocalize, limp, or otherwise show pronounced signs of their pain. They may attribute changes in behaviour related to pain as merely being due to aging. Some of the subtle behaviour changes associated with pain reflect the ten subtle signs of sickness in cats (see The Healthcare Needs of Cats).

When discussing pain with clients, even the suggestion that their cat might be in pain can be upsetting because it might make the client feel that they have been missing the signs in their cat. It is helpful to start with a series of questions that are included as part of the history regardless of the reason for the visit.

Questions That Assess Mobility Can Be a Useful Tool

  • Is your cat less willing to jump up or down than previously?
  • Is your cat unable to jump as high as previously?
  • Does your cat need to use a chair or other object to reach the same height as previously?
  • Does your cat show hesitation when trying to jump up or down from objects?
  • Does your cat play with other animals or toys less than previously?
  • Does your cat have difficulty getting into or out of the litter box?
  • Have there been changes in your cat’s litter box use (e.g., elimination near the litter box)?
  • Does your cat show signs of being stiff when he/she walks or runs?
  • Does your cat have stiffness after waking up that improves with movement?
  • Does your cat have difficulty going up and/or down the stairs?
  • Is your cat lame when walking or running?

Common comments used in rationalizing changes related to pain:

  • ‘He is getting old’
  • ‘Not jumping up as he used to’, ‘misses jumps’
  • ‘Sleeps a lot, but that is normal for his age’
  • ‘Not using the litter box because he is mad at us/me’
  • ‘Just doesn’t like to sit on that perch anymore’

Out-patient Observation and Handling

Observation of the patient during the initial consultation can be very beneficial to the clinician in identifying signs of pain. While taking the history, allowing the patient to roam freely about the consultation room will give the clinician time to observe gait, posture, body condition, and overall mental status of the patient. Changes in any of these may indicate pain. Careful handling of patients during their visit is critical. An assumption that every patient is in pain will reduce the risk of hurting a patient or generating a defensive, potentially aggressive response.

Carriers that open from the top allow gentle lifting of the cat out in cases where the cat will not voluntarily exit the carrier. Cats should not be dumped or pulled from their carriers. Attention to cat-friendly handling techniques is essential. If a client has specifically noted a part of their cat’s body that is painful, particular care should be taken when assessing that body part. During the physical examination, the patient should be watched for indicators of pain. The patient may be reluctant to be handled, have painful dental disease, dehydration, cachexia, or obvious wounds indicating pain. More subtle signs of pain during palpation may include wincing, grimacing, pinning ears backward, shifting of body weight, flicking of the tail, and attempts to escape. If a patient has a confirmed history of pain, obvious physical change indicating pain, or if the clinician has an index of suspicion that the patient may be in pain, pain medication should be administered prior to proceeding with the physical examination.

The Feline Grimace Scale is a validated tool that helps identify pain by grading whisker, ear, eye, muzzle, and head position. Please see Resources. 

Identifying Pain: In-patient Assessment

Hospitalized patients should be monitored, assessed, and treated for pain regularly throughout their hospital stay. Initial pain assessments should be based on the observations made of the patient prior to hospitalization. Use of the Feline Grimace Scale as well as acute and chronic pain tools is recommended. Assignment of specific individuals to conduct these assessments should be based on appropriate training, experience, and skill level.

Validated pain scoring systems for cats have been more difficult to develop than for the dog. One acute pain scale and one chronic pain assessment tool are undergoing development and validation and are recommended for the general practitioner.

Pain Prevention, Treatment, and Management

The most effective analgesic protocols are multimodal in nature. Combining drugs and therapies that influence different parts of the pain pathway results in improved efficacy and reduced risk of adverse effects.

Various analgesic drugs and protocols are available for cats. For management of acute and perioperative pain, opioids form the cornerstone of treatment. Combining opioids with other treatments, such as non-steroidal anti-inflammatory drugs (NSAIDs), constant rate infusions and regional anesthesia, improves analgesic efficacy.

The WSAVA Global Pain Council Guidelines includes suggested pain management protocols for different situations.

Other pain management modalities may be incorporated, including:

  • Potential disease modifying agents (e.g., glucosamine/chondroitin, polysulfated glycosaminoglycans)
  • Environmental modification
  • Therapeutic diets
  • Rehabilitative therapy

While some objective signs of pain can be determined by questioning clients and by repeatedly observing hospitalized cats, the most reliable assessment of the presence of pain is a return to normal behaviour in response to analgesic therapy.

Frequent assessment for pain is critical, not so much to determine if analgesia should be used, but rather whether additional modalities should be incorporated, if dose adjustments are needed, and to determine an appropriate duration of treatment.

Identifying and Treating Pain: Musculoskeletal Disease

A common reason for chronic pain in cats is musculoskeletal disease, degenerative joint disease (DJD) or arthritis. Based on radiographic evaluation in a number of studies, there is strong evidence to indicate that even young adult cats can have DJD. Therefore, DJD must be considered as a potential source of pain, even in young patients. Appropriate feline friendly handling techniques and application of analgesics to reduce pain-related stress should always be foremost in the clinician’s mind. For chronic degenerative musculoskeletal disease, multimodal analgesia and other modalities should be considered.

Analgesics which might be employed alone or in combination include:

  • Gabapentin
  • Guidelines for the long-term use of NSAIDs in cats have been published (see Resources)
  • Short-term narcotics for severe pain

Adjunctive modalities which may be used for DJD therapy include:

  • Chondroitin/glucosamine
  • Polysulfated glycosaminoglycans
  • Green-lipped mussel extract
  • Omega fatty acid supplements
  • Therapeutic diets for joint disease
  • Environmental management: Ensuring the patient’s environment is comfortable and that resources are easy to access will benefit both patient and client

In many cases, a response to therapy may be the most successful means of convincing clients that the cat is suffering from DJD pain. Ongoing evaluation via communication with the client, regular recheck examinations, and assessment of response to therapy will improve quality of life and reduce morbidity in patients suffering from DJD.

For hospitalized cats, signs of fear and anxiety may be similar to signs of pain. For example, body temperature and blood pressure are difficult to use as assessments of pain. Some observations that can assist in the recognition of pain include:

  • Tachycardia that persists after initial examination may suggest pain rather than fear or anxiety.
  • Tachypnea is frequently an indicator of pain; this is most easily evaluated by looking at the cranial abdomen, just caudal to the last rib.
  • Sitting in the back of the hospital cage rather than being interactive and interested may be a sign of pain or of fear.
  • Localized and repeatable discomfort on palpation of a body part may be more associated with pain than fear.
  • Changes in the patient’s behaviour; a normally compliant patient becomes defensive or vice versa.

Questions to Ask Owners about Potential Signs of Pain

  • Have you noticed changes in your cat’s sitting or sleeping position (e.g., lying flat out, difficulty settling down, resting in a hunched position)?
  • Has there been a change in your cat’s sleeping or resting places (or hiding in unusual places)?
  • Has there been a change in your cat’s energy level (i.e., more lethargic or more restless)?
  • Has there been a change in your cat’s personality or attitude (e.g., changes in interactions, irritability, wanting more attention or less attention)?
  • Have there been changes in your cat’s hair coat (e.g., matted hair, poor grooming)?
  • Have you noticed a change in your cat’s facial expression (e.g., staring, fixed gaze, dilated pupils, “squinting” eyes)?
  • Have there been any changes in your cat’s appetite or water consumption?
  • Does your cat lick or bite at a body part?
  • Is your cat more or less vocal than in the past? Are there changes in the type of vocalization?
  • Have there been changes in your cat’s litter box use (including inappropriate elimination)?

FELINE SPECIALIST AUTHORS

  • Susan Little, DVM, DABVP (Feline Practice) Bytown Cat Hospital, Ottawa, Ontario
  • Diane McKelvey, DVM, DABVP (Feline Practice) Aberdeen Veterinary Hospital, Kamloops, British Columbia
  • Elizabeth O’Brien, DVM, DABVP (Feline Practice) The Cat Clinic, Hamilton, Ontario
  • Elizabeth Ruelle, DVM, DABVP (Feline Practice) Wild Rose Cat Clinic of Calgary, Calgary, Alberta
  • Kelly St. Denis, MSC, DVM, DABVP (Feline Practice)
  • Margie Scherk, DVM, DABVP (Feline Practice) catsINK, Vancouver, British Columbia


    Please Note: Not all resources are available in both English and French.