Читать книгу Pet-Specific Care for the Veterinary Team - Группа авторов - Страница 187

Neoplastic pain, especially osteosarcoma (OSA) and any tumor metastasizing to bone, is generally considered to include a neuropathic component facilitated in part by osteoclastic activity. In palliative care circumstances (e.g., limb‐sparing OSA), multiple modalities should be deployed since undercontrolled pain will predicate the decision for humane euthanasia. As cyclooxygenase (COX) enzymes are greatly upregulated in OSA, NSAIDs are appropriate medications to deploy, along with one (or more) adjunctive pain‐modifying oral medications (among the higher effectiveness:safety ratios in human cancer‐related pain are anticonvulsants like gabapentin). Oral acetaminophen and opioids are frequently deployed in humans with chronic cancer pain, and can be utilized judiciously in dogs (not cats), but the bioavailability and clinic impact of these drugs have been questioned. Long‐acting (days, not weeks) parenteral opioid medications are available for off‐label use in dogs and cats. Uniquely in cancer pain, bisphosphonate (pamidronate, zolendronate) infusions freeze osteoclast activity and can elicit durable (approximately one month) improvement in a majority of dogs [6].

Nonneoplastic maladaptive and/or neuropathic pain syndromes described in dogs and cats often have an identifiable cause, but not always; it may be associated with identifiable inflammation, but not always. If an underlying condition is identifiable, it should be managed accordingly. To treat pain directly, if there is a grossly inflammatory component to the condition then antiinflammatory agents (NSAIDs or, when indicated, corticosteroids) can and should be utilized. But if there is no gross inflammation then antiinflammatory agents are unlikely to be beneficial, and one would gravitate to those medications and modalities which address hypersensitization leading to maladaptive and neuropathic pain. Chief among these would be gabapentinoids and possibly amitriptyline, amantadine, serotonin and norepinephrine reuptake inhibitors (e.g., venlafaxine) among others (clinical data limited).