Is He in Pain?

By Dr. Gail

This is a question our clients ask us every day. Since pets can’t speak for themselves, it is our deepest obligation to answer for them correctly. By identifying and managing pain appropriately, we can increase a pet’s quality of life and avoid premature euthanasia. First, what is pain? Pain can be defined as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage” 1 . It can be caused by tissue disruption, as in acute pain due to surgery or trauma. More commonly in end-of-life care, we will be facing pain caused by chronic conditions such as arthritis and cancer. While pain due to osteoarthritis is from joint wear and tear resulting in cartilage degeneration and a vicious cycle of inflammation, cancer pain is variable depending on the type of cancer and its location. There are tumors that invade bone, skin, muscle, nervous tissue, organs, body cavities, and so on. Pain in these conditions can be caused by compression and inflammation of tissue surrounding the tumor. To make things worse, some cancer cells also secrete chemicals that can cause an abnormal response to pain or even non-painful stimulation. This results in exaggerated signs of pain for some patients. 2 So, what might we observe? We could see changes in attitude, such as hiding, lethargy, depression, anxiety and possibly submissive or aggressive behavior. Sleep patterns may be affected as well, and commonly nights are more restless than days. Body movement may deviate from normal, including decreased activity, limping or just a subtle change in weight-bearing. Sometimes elimination posture changes, or our pet may be trembling/shaking or flinching from touch. Facial expressions of pain include furrowed brows, ears flattened against the head and eyes can appear unfocused or glazed. Dogs will commonly lick or even bite at an affected area. Vocalization may be seen with chronic pain, but often is not. If whimpering, groaning or crying occurs, the cause of the vocalization could be pain or attempts to communicate other needs such as elimination or hunger and thirst. If pain is severe, we could see decreased or absent appetite. Many of these signs are not specific for pain only (for example, kidney disease or liver disease may cause depression, lethargy and anorexia) but when these signs are seen in combination and when other diseases have been ruled out, pain is likely. 3 Once we’ve determined that pain is present, we can quantify the degree of pain using a pain scale. One useful scale is the Colorado State University Chronic Pain Scale (http://www.vasg.org/pdfs/CSU_Acute_Pain_Scale_Canine.pdf) This is a visually oriented scale that looks at behavior, posture and response to touch in order to determine the degree of pain. (If there is any possibility that your dog might be so painful that he would nip or bite, please do not touch the affected area). Another scale is the Canine Brief Pain Inventory (https://www.vet.upenn.edu/docs/default-source/VCIC/canine-bpi.pdf?sfvrsn=6fd20eba_0). This questionnaire allows evaluation of the degree of pain and how the pain interferes with function in everyday life. The utility of these scales rests in the ability to quantify the degree of pain, observe how it changes over time, and make decisions based on the results. If you think your canine companion suffers from pain or discomfort, please seek the help of your veterinarian to determine the cause. We are here to help if and when you and your vet think hospice care is the best option.

References:

1. Position Statement: The Treatment of Pain in Animals. American College of Veterinary

Anesthesia and Analgesia.org

2. Rincilio N., Poulson J, Ko J. Strategies for Managing Cancer Pain in Dogs and Cats, Part 1:

Pathophysiology and Assessment of Cancer Pain. Todays Veterinary Practice May/June 2015.

3. Balakrishnan A, Benasutti E, Pain Assessment in Dogs and Cats. Todays Veterinary Practice,

March/April 2012.