Pain management is a vital aspect of equine welfare, and plays a pivotal role in the rehabilitation and recovery process post injury or illness. Optimal recoveries can raise the level of the horse’s comfort and wellbeing, whilst simultaneously reducing the negative impact of pain on their health, behaviour and performance. Pain can be debilitating for any horse, and in certain cases is primarily responsible for the requirement of euthanasia. Unfortunately, adequate pain management may be expensive, difficult to evaluate, and traditionally requires frequent drug administration.
Pain is an essential component of the body’s defence system, it enables a motor response to minimise physical harm and initiates a physiological response to heal damaged tissue. In the absence of inflammation, pain receptors are activated and will normally reflect the intensity of a specific external stimulus. Whereas, in the presence of inflammation, pain can arise with a minimal stimulus or even without an external trigger. Inflammation represents an immune response to injury or infection; and the inflamed tissue is characterised by pain, oedema (swelling) and heat. The development of inflammation involves a series of physiological mechanisms aimed at defending the body from potential pathogens or foreign substances. It also activates the healing process. Despite the fact that pain and inflammation are part of the body’s defence mechanism, it is essential to manage them appropriately in order to mitigate significant consequences.
Prompt detection and precise determination of the source of pain is crucial for effective management.
However, accurately recognising pain in horses can be challenging for a number of reasons. Similar to humans, horses can vary in their individual responses and displayed signs of pain. For example, sensitive horses often express greater levels of pain, while more laid back horses will sometimes ‘underplay’ their level of pain. From an evolutionary standpoint it is thought that herd animals which could be subject to predation are instinctively programmed to hide their injury or vulnerability for survival. This primal instinct can make it difficult to get a true indication of the levels of pain felt by equines. Evaluation of pain in horses therefore requires careful interpretation of abnormal, pain related behaviour.
There are a number of advantages and disadvantages associated withthe most commonly used medications and methods for managing pain in horses. However, there is a general consensus that a combination of interventions form the most efficacious approach to manage and treat pain. The methods used to manage pain will depend on the duration, type and severity. A short course of pain relief is often required whilst diagnosis and treatment plans are undertaken, however, in cases of chronic pain, longer term or indefinite treatment may be needed to control comfort and quality of life. For example, a horse suffering from arthritis of the joints will require a long term pain management strategy. Unfortunately, this is where dosage and side effects can become more problematic, as many owners are unaware of the hidden side effects of common equine pain medications.
Non-steroidal anti-inflammatory drugs (NSAIDs) are the most commonly used drug for pain management in horses.One of the most common is the drug phenylbutazone (often referred to as Bute orEquipalazone), flunixin (e.g. Equinixin) and meloxicam (e.g. Metacam). These medications are used to relieve pain and help reduce inflammation and fever. However, as with any medication these drugs do have known side effects, and balancing the benefits of treatment with the risk of side effects must always be considered. Side effects of NSAIDs include gastrointestinal disease (such as stomach ulcers, colon ulcers and diarrhoea) and kidney damage. The risk of side effects are also higher for young, old, sick or dehydrated horses.The most serious side effect of Bute is a condition called Right Dorsal Colitis. The horse’s upper right side becomes inflamed as a result of the drug inhibiting chemical secretions that protect the lining of the gastrointestinal tract. Consequently, the colon can become inflamed and in some severe cases it can be deadly. Unfortunately, it is not just large doses of the drug that can lead to such side effects, as long term exposure and even within recommended doses can be dangerous.
Whilst pain medications are often necessary and effective measures for managing pain, there has become a fast-growing global trend focused on alternative methods of pain management. Microcurrent stimulation can be used as an adjunct treatment to support the recovery of injured equines. It is known to:
Microcurrent stimulation (MCS) represents one of the electrotherapy modalities, which aims to bring about a number of health benefits, including but not limited to the reduction of pain and inflammation. Experimental findings suggest that MCS application mediates a number of different localised and systemic benefits. These benefits, including pain reduction, can be attributed to the MCS derived effects that counteract the pathophysiological changes occurring within the traumatised or dysfunctional tissue. Trauma or dysfunction impairs the bioelectrical potentials of the affected cells, and many of the MCS benefits are mediated through the restoration of such bioelectrical potentials. Moreover, compared with the healthy tissue, the affected tissue is characterised by a higher electrical resistance. As a result, the electrical conductance and tissue capacitance are decreased, thereby hindering the endogenous bioelectrical current. This contributes to impairing the healing process and prolonged inflammation. The reduced membrane transport also diminishes the metabolites and nutrient influx into the cell, as well as the waste products removal. All these changes impair normal function, and are also conducive to the development of pain. MCS application to the dysfunctional or injured tissue emulates the body endogenous bioelectrical current, is thought to augment ATP synthesis and membrane active transport, which are important to re-establish normal tissue function, healing and improving pain.
Therefore, the incorporation of advanced EquiPod microcurrent treatments into a pain management care strategy could be highly beneficial for many horses, including those that are;
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