What a pain!

Pain management ( of Non-malignant cause )is still a very much more of an art than a science and those who like black and white solution to clinical problem will be disappointed.

Acute Pain
Acute pain, associated with trauma or surgery, is generally easier to manage than chronic pain. This is because the type of pain is usually related to form of tissue damage resulting in excitation of nociceptor nerve endings. Few would deny that the use of potent opioid drugs in these circumstances is worthwhile.

Chronic Pain
Chronic pain is defined as pain lasting more than three months which is the upper limit of normal time for wound healing. Patients experiencing pain do not present with objective signs or symptoms as they would with high blood pressure or a raised blood glucose level.

There are three types of pain behaviour:

• Nociceptive pain due to excitation of mechanical, thermal or chemical nociceptors
• Neuropathic pain, defined as pain related to disease or injury of the peripheral or central nervous system
• Pain disorders that exist when it is not possible to explain the patient's symptoms on a physical basis. Pain disorder can be subconscious ( conversion disorder ) or conscious ( malingering ).

Management:
Non-pharmacological treatment plays an essential role in the management of chronic or persistent pain.
Firstly, it is important to reassure the patient that there is no serious underlying pathology, giving a simple but understandable explanation of the causes of pain.

It is recognised that because of a patient pressure a request for an X-ray or CT scan will usually be made. A careful explanation of these findings are needed because patients may interpret relatively benign reports in an alarmist way, further reinforcing abnormal beliefs about the cause of their pain.

Secondly, patient expectation need to be addressed to ensure that they are realistic. For many patients, whether they have nonspecific pain issues or specific but not otherwise treatable conditions, resolution of all pain symptoms is often impossible and patient's expectations need to reflect this. However, it is important to emphasie that despite pain, an improvement in function and quality of life is still possible.

Thirdly, Unlike acute pain management, physiotherapy is important to rehabilitate the patient and bed rest must be discouraged. The major aim of the whole management program is to improve activity and functional status of patients with the hoping returning back to usual employment.

Excessive reliance on passive coping strategies such as medication should be discouraged. Often patients with chronic pain are deconditioned and has high BMI due to psychological problem, unhealthy life style and lack of movement due to pain.

Fourthly, It is important to address the patient's psychosocial problems.

Due to persistent pain, many of these patients are unemployed, on disability pension adding to financial burden. They are therefore prone to suffer anxiety, depression and low self esteem.
Moreover, they are more likely to be socially isolated and has unhealthy life style such as smoking and drinking leading to cardiopulmonary diseases.

Psychologist referral should be made for cognitive behaviour therapy for the patient to be able to cope with the pain and related psychological problem. If low mood is detected, then use of antidepressant such as SSRI should be considered.

Despite the best efforts, some patients seem to rely soley on mediations and fail to engage in an appropriate rehabilitation program. These patients are sometimes referred to as ''chemical copers''. Management of these patients should involve clearly set boundaries, especially with regard to request for extra medication. Care should be taken to avoid unnecessary investigations, referrals and treatements. Significant support is required from the treating doctors, as well as allied health professionals, family and community services.

Pharmacological treatment:
Recent meta-analysis demonstrate a modest reduction in pain with dosages of upto 100 mg per day of morphine equivalent but this is not always accompanied by improved function. There is some agreement that in patients already receiving regular opioid medication for persistent pain, a ceiling for the total daily dose should be considered. Some authorities have suggested a ceiling of 100 mg per day morphine equivalents.

Surgery is no panacea and it may provide some temporary relief from pain such as facet joint injection in chronic back pain.

For neuropathic pain, first line medication is tricyclic antidepressant and if they are unable to tolerate it then pregabalin or gabapentin are recommended. Second line agents include anticonvulsant such as valporate or carbamazepine and serotonin noradrenaline reuptake inhibitor.