Pain relief as an independant speciality

Dr Lakshmi Vas

Medicine is all about relieving pain and suffering. Ironically, in modern medicine, its disease and its treatment that assume foreground, while the physical pain and mental suffering of the patient is pushed to the background. This underscores the need of special pain clinics in the city.

Though, pain is usually a useful warning symptom of some disease or damage, however, there are many conditions where pain has no purpose, or function and can cause untold misery to the sufferer. There are many such varieties of this ‘useless pain’ which could be an aggressive disease of the nervous system that can cripple the patient.

Chronic pain is one such variety. It is an affliction with untold suffering that erodes the tolerance and self respect of the sufferer. It has serious financial consequences to the patient and the society.

Most of these patients would have already consulted various specialists but without avail as there may be nothing amenable to traditional treatment.

The pain clinic which concentrates on pain relief irrespective of its cause forms the final stop for these patients. Realisation of this problem has led to the establishment of dedicated pain clinics in the western world. Unfortunately, India has lagged behind in this respect.

There is hardly any dedicated, organised multimodality facility for pain relief anywhere in the country. The number of patients suffering from various levels and types of pain, from a mild to severe and excruciating pain is phenomenal even in our society.

They are presently told that ‘they have to learn to live with it’ when pain is from a cause like cancer, and when the cause is not easily comprehensible they are dismissed as ‘it is all in your head’ and doomed to a lifetime of suffering and depression.

All that is required for effective treatment of these pain is an acceptance of the need for a new specialty and its development by way of dedicated dynamic personnel and providing them with an atmosphere conducive to progress.

There is no dearth of patients in pain. All that is needed is an education of doctors and public alike of the conditions that merit treatment in a pain clinic.

Conditions treated in pain clinic

Cancer pain- (20-25 per cent), Back pain and radiculopathy, lumbar and cervical pains (30-40 per cent), Myofascial pain syndromes.(0-15 per cent), Complex regional pain syndromes ( 5-10 per cent) and others (5 per cent) besides headaches, migraine facial pain, neuralgias, central pain syndromes (Deafferentation pain after stroke, or trauma to spinal cord brainstem, brain, post amputation stump and phantom limb pain), painful medical disease (chronic pancreatitis, HIV, Sickle cell disease etc), chronic pelvic pain acute herpes zoster and post herpetic, painful peripheral neuropathy.

Approach to pain management

The patient is evaluated to find a pain generator, either nociceptive (organic) or neuropathic and the psychological impact of the two on the patient. The actual treatment will involve:

1. Initial trial of medications (analgesics antidepressants, anticonvulsants, muscle relaxants etc) TENS and reference to the clinical psychologist where necessary.

2. Interventional procedures like nerve blocks with local anaesthetic, steroid, clonidine, or advanced procedures. The extensive mandatory use of fluoroscopy for pinpoint accuracy of the nerve blocks so that the patient does not suffer from indiscriminate destruction of nerves as may happen with blind techniques.

To ensure accuracy, nonionic radioopaque dye is injected under fluoroscopy to ensure that the injection is going where it is supposed to go.

3. Identifying the exact location of the nerve inflammation and then inject the ultimate anti-inflammatory agents like steroids to the exact site of pain is the mainstay of present day injection therapy. The steroid is triamcinolone or depomedrol has a slow release formulation which sustains the anti-inflammatory effect for 2 to 3 months to ensure that the nerve heals over that time.

Intramuscular stimulation (IMS)

Intramuscular stimulation (IMS) is a diagnostic and therapeutic technique for most varieties of myofascial pain. Most of these pains are a manifestation of incipient radiculopathy (prespondylosis) secondary to degenerative changes in spine and paravertebral muscle (prespondylosis).

These changes are so subtle that they cannot be detected by laboratory and imaging tests. However these changes are discernible as muscle shortening especially Para vertebral muscles, to an exploring needle. These are secondary to the radiculopthy.

IMS has introduced an examination technique of detecting muscle spasm or shortening in deep muscles that are normally inaccessible to the palpating finger by a probing needle. The same needle is used to cause a relaxation of the spasm. It borrows its needle technique from traditional acupuncture but its application for myofascial pains is based solidly on anatomy and neurophysiology and the treatment is directed towards anatomically determined muscle motor points with expected predictable end points.

This IMS radiculopathy model explains many apparently different and unrelated pain syndromes from headache (some of the so called migraines) to low back pain, from tennis elbow to trigeminal neuralgia and places them all into one classification. The needling produces a local inflammation with release of mediators that promote healing with disappearance of local pain.

In addition it sets up afferent impulses to the spinal cord to cause a prolonged reflex stimulation for days till the miniature wounds from the needle heal. This induces a prolonged relaxation of the deep muscles. There is also a stimulation of the autonomic fibres, which control the musculature of blood and lymph vessels.

Physiotherapy:

Most of the pain from locomotor system stems from or is worsened by inactivity. Mobilisation forms the most important part of treatment of non malignant pains. So most of the pain treatment have to be followed by physical therapy.

Yoga is probably one of the greatest gifts of India to mankind. It is extremely scientific in its design to systematically exercise the muscle groups in sequence in a gentle guarded and graded manner. Many asanas target and exercise muscles which have not even been thought of in modern physical therapy.

Another great advantage of Yoga is that it raises self awareness( conscious proprioception) and helps the patient in an objective assessment of his pain. This gives an indirect help in depression by motivation. Many of the pranayamic practices can be used for biofeed back techniques as well as auto suggestion to reduce the pain by recruiting cerebral facilitation and inhibition pathways in the management of pain.

Acupuncture

It is an accepted modality of pain treatment by WHO. It forms an extremely useful tool in a pain clinic for all the types of pain but is particularly effective for conditions like migraine neuralgias neuropathies etc particularly in difficult pain conditions like RSD, backache where a pain generator cannot be located etc. It is also useful in some unusual situations like addiction smoking etc. It also functions as a bridge between modern pain treatment of nerve blocks and functional physiotherapy.

Long term solutions for some serious types of pain:

Use of implants like spinal cord stimulators for treating the pain of chronic backache, refractory angina, failed back surgery etc has revolutionised the lives of sufferers, enabling them to have a normal productive life.

In patients with pains refractory to repeated blocks:

Sophisticated therapies like Spinal cord stimulators and intrathecal drug delivery with an implantable computerised or gas driven pumps (medtronics, Codman O) are now available in India. Implantation of sophisticated titanium pumps for continuous intrathecal infusion of morphine clonidine and baclofen have revolutionised the outlook for sufferers of chronic intractable pain of cancer, demyelinating disorders, arachnoiditis , failed backs etc.

They are particularly useful in patients of long standing back pain where surgery is not possible or has failed and medication difficult with risks of renal problems with NSAIDs and addiction with opioids.

Intrathecal pumps and spinal cord stimulators are a boon to this unfortunate group with a long life expectancy but a life full of pain. They provide a level of pain relief is compatible with an independent and productive life with supportive medications.

Use of intrathecal pumps for other types of chronic pain and cancer pain makes life livable to these unfortunate patients and adds a quality to whatever time they have left with their family. Once implanted, these pumps have a life of seven years. They have a peristaltic pump driven by electronic circuit in a microchip inside the pump. There are other pumps which are driven by a regulated expansion of Freon and such agents. They are capable of injecting accurately doses of morphine as minute as 0.02-0.04 mg/hr and have facilities of delivering a bolus dose at a specified time of the day, and vary the doses between day and night.

The volume of morphine in pump gets exhausted in about two and four months depending on the patients requirements and the morphine needs to be refilled once in every two to three months in an outpatient visit. The quality of pain relief afforded by these pumps has to be seen to be believed.

Cancer patients who had nothing but excruciating pain to occupy their days and sleepless nights find themselves choosing a life which has suddenly become worth living. The procedure involves the passing of a Teflon catheter into the subarachnoid place at the topographic level in the cord supplying the painful area of the body. The catheter is then passed in a subcutaneous tunnel to the anterior abdominal wall where the pump is implanted.

The writer is consultant anaesthesiologist at Breach Candy Hospital, Mumbai
Email:lakshmi1@hotmail.com.