Pain management in small animals: A review article

In critical care, and/or in the perioperative setting, pain is often a major component of the clinical picture. It is often of inflammatory origin, because all the chemical mediators of inflammation stimulate or sensitize the nociceptors. It can also be of mechanical origin, for example when it is associated with dilatation of a hollow organ or with compression, laceration or destruction of tissue. In such cases, intensive pain appears soon after the injury and is amplified later when inflammation sets in. Finally, pain can arise from the brain stem, through direct excitation of the pain-transmitting spinal neurons. When pain is poorly managed it is a source of complications that make the prognosis more uncertain. Multimodal analgesia is based on a concept that is also used in general anesthesia and in cancer therapy. The principle is simple: when tackling a complex and multifactorial process, the benefit/risk ratio is improved by using a combination of different approaches. Their beneficial effects are additive, and each one is used more sparingly to limit their individual adverse effects. For a long time, non-steroidal anti-inflammatory drugs and opioids were used alone singly, and it was proposed to use one or other type depending on the intensity of the pain. The problem is no longer put in these terms. A combination of several molecules is used in all cases and the analgesic protocol changes depending on the type of pain.