It combines factors that contribute to pain, contradicting the pattern theory which suggests that nerves are shared with the touch senses and that the pattern of activity in the nervous system is responsible for transmitting pain; Melzack and Wall state that there are separate nerves and different receptor fibres to perform different functions.
The gate control theory suggests that a neurological ‘gate’ is present in the spinal cord that can block or allow pain signals to travel to the brain. This ‘gate’ is able to differentiate between the types of fibres which carry pain signals through the body, although there has never actually been any physical evidence to support this.
This theory states that within the spinal cord is a gate mechanism that controls the messages of pain. It is the messages coming from the pain fibres at the injury site which control the gate. For example if you hurt your ankle pain fibres will activate the small fibres and the projection neurons which will then block the inhibitory interneuron allowing the messages to pass through and opening the gate therefore meaning pain is felt.
Physical conditions such as stimulation through rubbing the affected area, emotional conditions like rest and relaxing and mental conditions such as distraction are all factors that can lead to the gate system closing after an injury has occurred. Knowledge, beliefs and past experiences can affect people’s perception of pain. For example soldiers that are injured whilst on duty will block out the pain as they are relieved to still be alive.
There is also the cognitive model of pain which mainly focuses on psychological and cognitive factors as being critical determinants in the perception of pain (Davey, G. 2004). This model suggests that depression and anxiety will cause higher levels of pain within sufferers. It could raise the question of which came first, the pain or depression?
Key methods of pain assessment
Assessment of a patient’s experience of pain is a crucial component in providing effective pain management (Wood, S. 2008). Melzack and Katz 1994 regard the self-report assessment method as being gold standard as it provides relevant information for professionals and enables selection of pain relief and evaluations to take place over the effectiveness of methods being used.
According to the palliative care guidelines, 2009 there are five key questions regarding pain assessment these are; is the pain severe and overwhelming? What is the pain like? What is causing the pain? Is it a specific type of pain? And are other factors adding to the distress? Although these questions provide valuable information self-report is based on opinion, this could lead to individuals providing false information, and for example some individuals may exaggerate the pain being felt whereas others may feel that they are wasting the time of professionals. As a result of this incorrect diagnosis may occur ultimately prolonging the pain and recovery process.
There are individuals who are unable to provide the self-reporting assessment method, for example individuals who are unconscious or young children, in this case observational techniques could be used. This is done by observing physiological responses such as facial expressions and movements etc.
Behavioural assessments are sometimes necessary in older people and people that are unable to talk. There are a couple of tools that can be used to assess pain in these individuals which are; the Abbey tool and the Doloplus 2.
The Abbey tool was positively reviewed by Herr et el, 2004 for being quick to use and easy to follow although it was criticised as more testing is needed in order to find how reliable it is.
As the Doloplus 2 has not been tested in English speaking countries it was criticised although Herr et el, 2004 has described it as being ‘a comprehensive tool based on sound assumptions of the multidimensionality of pain’.
Beecher (1956) observed soldiers’ and civilians’ request for pain relief in hospital during the Second World War and reported that although soldiers and civilians showed the same degree of injury, the soldiers requested less medication (Naidoo, J and Wills, J. 2001). This suggests that cognitive processes play a major part in the reflection of pain on individuals, for example the soldiers saw the pain as positive as they were out of the war whereas the civilians were losing money being off work therefore the pain had a negative impact on them.
Psychological factors can affect the amount of pain that an individual feels an example of this is if the individual is experiencing pain over a long period of time and stops working, exercising and generally becoming less active due to the fear of increasing the pain. This will cause muscles to weaken and their physical condition to decline as the individual may start to develop negative thoughts regarding themselves and beliefs about the pain being eradicated. These factors are likely to cause the individual to become depressed fuelling and maintaining the pain cycle.
There are social and emotional experiences which can influence an individuals reaction to pain and pain management, one example of this are people who receive regular blood tests/injections do not worry or feel anxious about having them done as they are aware that the pain is slight and the feeling does not last very long, whereas people who have never had any blood tests/injections will not know this making them feel anxious or nervous.
Communication around people experiencing pain plays an important role in the way that the person react, for example falling over although pain is felt people tend to feel worse if a fuss is made this is most visible in young children, when parents/carers shrug the fall off the child tends to get up and carry on as normal whereas when the parent/carer fusses the child reacts by crying and needing cuddles etc.
Other examples of social and emotional experiences include bravado generally in men, when they injure themselves they do not complain in front of their friends as they feel that it is not ‘cool’ to do so. The problem with this is that the healing process and pain management cannot begin until the individual acknowledges the pain. Shock is another condition which can cause an individual to stop feeling pain meaning that management of this pain is unable to start.
Approaches to pain management
Pain management encompasses pharmacological, non-pharmacological and other approaches to prevent, reduce or stop pain sensations (Gale Encyclopaedia. 2008). In cases of chronic pain, most specifically, the aim of pain management and control is to help the individual to gain control over pain and also to improve their quality of life, it is not always about relieving the pain.
There are three approaches to pain management which are; the medical approach, behavioural approach and the cognitive approach. Within these approaches are many different techniques which enable people to manage or eradicate pain.
The medical model is defined by Fritscher, L. 2009 as being a school of psychological thought in which mental disorders are believed to be the product of physiological factors and that it treats mental disorders as physical diseases. Methods within this approach focus on targeting the pain which would support this definition.
Within the medical model methods include medication such as morphine which is an intravenous pain relief belonging to a group of drugs called narcotic pain relievers. It is used for moderate to severe pain and is administered by doctors/nurses. The way in which it works is by dulling the pain perception centre within the brain therefore bringing in the gate control theory. Although morphine is a fast acting form of pain relief there are many side effects that can be caused by the medication. Also it is extremely addictive.
Another method within the medical model is the TENS machine which is not medicated meaning that there is no chance of becoming dependant on it. The TENS machine eases pain by delivering small electric pulses to the body through electrodes which are placed on the skin. The machines are easy to use and can be used when moving around as they are small and light in weight.
Alternative methods can be used within this model such as acupuncture which is an ancient system of healing achieved by balancing chi in the body by the insertion of needles into strategic body points (Jackson, J. 2006). This procedure involves needles being placed into specific areas of the body it is argued that acupuncture is ‘useless’ as there is no way of testing the procedure with scientific instruments. Some people find that it does ease their pain. As this is an invasive treatment there are a few precautions and also has to be performed by specialists that are trained to perform the procedure.
With the behavioural approach to pain management the emphasis is placed on behavioural methods for example if a person was experiencing pain due to weight issues it may be suggested that they diet. This would help them to lose weight and also to relieve pain. Some people may struggle with dieting and it may not necessarily relieve any pain although there would be other benefits to their health.
The cognitive approach puts emphasis on the thought processes that are linked to pain experiences. There are a few cognitive methods which can help with pain management one of these being refocusing attention away from the pain for example if a person falls and bangs their knee, thinking about the pain is likely to make the pain feel worse whereas concentrating on an activity may help to reduce the level of pain being felt, of course this depends on the severity of injury that has occurred.
Having described the different approaches to pain management I feel that by combining methods the sufferer would benefit more and recover faster. For example once the initial pain assessment has been done if the professional was to prescribe medication such as aspirin for a sprained ankle, then suggests for the pain sufferer to rest their ankle for a few days as well as refocusing their attention away from the injury they are more likely to manage pain more effectively therefore reducing healing time.