Treatment modalities in pain management play an important role when dealing with different circumstances which include the following :
1. Treatment of Disease (Cancer) in pain management :
After the diagnosis and confirmation, appropriate therapy has to be started, especially for symptom ‘pain’. Symptom like mucositis, dysphagia etc, can be controlled by using local anesthetics, local application of antifungal in mouth, which will control oral thrush and reduce pain and burning caused by it.
2. Analgesics and Adjuvants in pain management :
WHO has provided a ladder for use of analgesics and other adjuvants.
3. Custom opioids in treatment modalities in pain management :
Like remifentanil (01847084 B), which has been recently introduced, is unique and has unusual pharmacokinetic characteristics:
a) As an ester, it is subject to ester hydrolysis by nonspecific plasma and tissue esterase, resulting in extremely effective metabolism into inactive compounds.
b) As compared to fentanyl and its older congeners (alfentanil, sufentanil), remifentanil has very short half life. Thus it is very short acting.
Treatment modalities in pain management using custom opoids offers various advantages:
a) It is very useful in finding out if the patient’s chronic pain is opioid sensitive or not.
b) In the treatment of short periods of breakthrough pain (such as bed to chair transfer of multi trauma or acutely injured patient).
c) All other specific advantages of fentanyl and its congeners are there involved in pain management .
Thus ongoing research will find out if in reality remifentanil will definitely offer specific advantages over conventional opioids or not. It also needs evaluation for its proposed ‘switch on/switch off’ role as on-demand analgesic/no side effect analgesic (opioid).
4. Computerized Drug Delivery Methods in pain management :
Recent advances to ‘pumps’ (drug delivery devices for administration of opioids) are ‘calculator pumps’, where physician specifies delivery rates of mg/hr or mg/kg and so on and so forth.
PCA pumps (patient-controlled analgesia) are one such modification of these pumps. Nowadays computer controlled infusion pumps (CCIP) are available by coding a pharmacokinetic model into a computer programme and linking it to an electrode pump to accept the computerized command delivery according to drug’s pharmacokinetic parameters. Thus, rather than an infusion, a target concentration is achieved.
5. Noninvasive Drug Delivery System (NIDDs) in pain management :
Here as the name suggests the stress is on absolutely non invasive approach without breaching the surface area of application to which the drug delivery system has been applied to (skin/mucous membrane). Few of the examples of these are:
a) Transdermal drug delivery especially transdermal therapeutic system for fentanyl (TTS-Fentanyl). The pain management goal is to provide noninvasive, continuous supply of fentanyl across skin to achieve adequate blood level of fentanyl to achieve adequate level of analgesia.
b) Eutectic mixture of local anaesthetics (EMLA) :
d) Transmucosal delivery system (TMDS)
e) Intranasal drug administration, e.g., nasal butorphanol, nasal fentanyl, nasal sufentanil.
f) Pulmonary administration of analgesics
6. Implantable Neuraxial Delivery Devices (INDD) in pain management :
For chronic pain relief, these are drug delivery devices which have to be implanted by interventional technique of pain management , neuro axially, to deliver potent analgesics for long-term outpatient treatment of chronic pain. Drugs like bupivacaine, morphine, ketamine, clonidine are used.
Continuous monitoring is done. The medications are given ‘by mouth’, ‘by clock’ and ‘by ladder’.
By mouth: most opioids are effective orally. For ease of pain management this route is used. Logically, almost 3 times the normal parenteral dose is required.
By clock: “SOS / PRN / AS REQUIRED” are useless terms. The pain is not allowed to “re-emerge or break through”. So doses are to be staggered as such that the next dose is already on board, before the effects of the previous one have worn off.
7. Neuro Stimulatory/Anaesthetic/Neurolytic/neurosurgical in Pain management : The inflammatory responses can be controlled by Corticosteroids, as they decrease swelling of nerves caused by compression; corticosteroids also effectively decrease headaches and other painful conditions like neck pain, stiffness etc, produced due to intracranial space occupying lesions (ICSOL).
Neuropathic pain under treatment modalities in pain management may be treated as follows:
• Tricyclic antidepressants, like amitryptiline, reduce burning sensation.
• Anticonvulsants, like sodium vaiproate, decrease shooting or stabbing pain.
• Neuraxial interventional techniques, like intrathecal! epidural continuous catheter infusion techniques of morphine, local analgesics, clonidine help in reducing radiculopathic pains.
• Ketamine may be employed in subanesthetic doses.
• Transcutaneous electrical nerve stimulation (TENS) may be of great value here.
8. Psychotherapy & Counseling in pain management :
Integral part of the chronic cancer pain syndrome are following:
• Stress, anger, fear, depression, anxiety, emotional outbursts.
These further increase the pain which require various non- conventional or psychotherapeutic measures.
9. Physio and Occupational Therapies in pain management :
Their aim is to make patients mobile, comfortable, overcome daily chores and make patients as independent as possible and bring some meaning to whatever life is remaining.
10.Treatment of Other Aspects of Pain in pain management :
• Pain of pathological fractures to be controlled by immobilization, plaster of Paris casts etc.
• Pain of gastrointestinal or other system obstruction need to be treated as part of pain management .
• Infection like upper respiratory tract, herpes stomatitis, UTI, needs their appropriate treatment which will decrease their pain.
• Constipation. usually this is due to opioids, tricyclics, anticholinergic drugs. Also can be a result of decreased mobility, low fiber diet and decreased fluid intake.
Pain management is done here with the help of laxatives. Laxatives have to be treated as adjuvant and given if required till end. Five groups of these drugs are:
– Contact laxatives: Act on large bowel. Ex: Sennasoids (Senna)
– Emollients: Liquid paraffin or Cremaffin are gentle laxatives and produce semisolid stools.
– Bulk laxatives: Like isabgol; they act physiologically. This pain management technique is useful even in chronic debilitated patients.
– Stool softeners: Dioctyl sodium succinate—decrease hardness of stool.
– Osmotic agents: Lactulose. In more resistant constipation this is very useful.
– Last but not least, mechanical methods like enema, glycerin syringes etc., are needed in resistant cases.
The management of chronic pain of oncogenic origin is a very complex phenomenon. The well organized, planned, evaluated and reassessed approach of pain management is necessary to avoid inadvertent and sometimes inhuman increase in suffering of already depressed, tired, anxious, angry and helpless patient.
Pain management needs to be very adaptive, flexible, intuitive and many a times very challenging. A multi-disciplinary team approach is the only solution to this problem!