PAIN

Pain itself is a complex process and relief from pain is a basic human right. Everybody is individual and pain is a subjective and personal experience, as is healing time after an initial injury, depending on the severity of the injury and the structure of the tissue involved.

Pain can be categorised as an unpleasant and distressing experience. Many patients have reduced mobility post trauma/surgery and it is important to have effective pain control to enable them to mobilise as immobility can lead to muscle wasting, pressure damage, deep vein thrombosis (DVT) and constipation. Pain can cause sleep and mood to be become greatly impaired which in turn can effect one's perception of pain and their outlook on rehabilitation or the current situation. With chest injuries the inability to cough, deep breathe and clear secretions could result in a chest infection and poorly managed acute pain leaves patients at high risk of developing chronic pain.

Types of pain

As previously mentioned pain is an individual experience and each patient will have their analgesic regimen tailored to their needs and the type of pain they have.

Pain can be categorised as nociceptive and neuropathic pain. It is possible to experience both nociceptive and neuropathic elements at the same time due to a combination of the primary injury and secondary effects.

Nociceptive can be visceral (felt in the internal organs of the body) or somatic (felt in the skin, and muscles). 

Visceral pain arises from inflammation or compression in or around internal organs, it is not always localised and often people find it hard to define or describe it, this can be felt like a pressure, aching or sqeezing.

Somatic pain can be either deep or superficial and arises when pain receptors in the tissues are stimulated. It is often localised pain and can be constant or stimulated by movement. There are two categories; superficial and deep.  It can be referred to as skin, tissue or muscle pain if it is superficial. However deep somatic pain can be described as a dull ache originating from joints, muscles, bones and tendons.  

Nociceptive pain can usually be helped with opioids and NSAIDs (Non-steroidal anti-inflammatory analgesics).

Neuropathic or nerve pain is caused by damage or injury to various nerve fibres in the nervous system which leads to impaired pain processing. Nerve fibres become hypersensitive leading to lowering of the pain threshold, increasing pain sensitivity and even pain in the absence of stimuli.  As a result neuropathic pain can be described as burning, electrical shocks, pin & needles, stabbing or shooting pains.

Neuropathic pain is usually helped using anti-neuropathic analgesics such as Gabapentin, Pregabalin, Amitriptyline amongst others.

Medication side-effects

All medications can be constipating so patients are usually advised to exercise as pain and rehabilitation allows, drink plenty of water, take laxatives as prescribed, and eat a varied diet including fruit.

Although it is important to take prescribed medications, individuals need to address how well the analgesics are working for them over time as well as the long term effects and side effects. Opioids can become less effective over time and patients can build tolerance or become dependent.

You should know what you are taking and why, stick to prescribed doses and take analgesics at the prescribed times. All medications are started at low doses and slowly scaled up to required effective doses. Over time, analgesics are slowly reduced back down when pain allows to when they are no longer needed.

It's important to be aware that high doses of opioids or anti neuropathic agents should not be suddenly stopped as this can result in withdrawal symptoms such as nausea, vomiting, sweating, insomnia and anxiety.

There is new legislation from The UK Department of Transport providing guidance for those attempting to drive or being in charge of a vehicle with a specified controlled drug in the body. Further information can be found here

Multi-modal approach to pain management

You may be on a number of different analgesics, also known as a multi-modal approach. The aim of a multi- modal approach is to facilitate superior pain relief as well as minimising opioid use and hopefully aid quicker recovery.

Patients may be offered a regional technique as part of their pain treatment for certain injuries. One off nerve blocks and local anaesthetic infusions can offer a highly effective mode of treatment for moderate to severe pain. This can either involve a one off nerve block injection and or the insertion of an indwelling catheter into the surrounding area of a targeted nerve which causes pain to a specific body region and provides analgesia by the infiltration of local anaesthetic which temporarily disrupts the transmission of nociceptive impulses from the injury site. It can be used as part as a multimodal approach to analgesia to reduce opioid requirements and side effects

Perception of pain

There are many factors which influence pain perception such as anxiety, lack of sleep, previous experiences, age, social circumstances, emotional influences and mood, response to others, self-efficacy (motivation), cultural beliefs, and personality. Patients are reviewed holistically and all factors will be taken into account when accessing ones pain.

Pain which lasts past the healing time (3 months according to The British Pain Society) could be deemed as chronic or persistent pain. Persistent pain is complex and can be difficult to treat.

Many treatments are aimed at reducing pain so patients can carry out their daily living activities. If you suffer persistent pain, however, it may be that you are never completely pain free. Persistent or poorly controlled pain can cause distress, upset, tiredness and wind up of the underlying pain. As a result, daily activity can be reduced, as well as a reduction in stamina and self-esteem which can lead to frustration and increased boredom which in turn can affect a patient’s personal life as well as relationships with others.  More information about persistent pain and strategies for minimising its impact can be found here.

This information has been provided by Leann Chaganis from the Inpatient Pain Service, St George's University Hospitals NHS Foundation Trust