Understanding Pain Management for Physicians

INFORMATION FOR PHYSICIANS:

Non-Cancer Chronic Pain Treatment
Pain should be identified as to whether it is nociceptive, neuropathic or mixed. Relief of pain by appropriate pharmacotherapy should be the aim. Various available classes of drugs are:

  1. NSAIDs
  2. Opiates
  3. Anticonvulsants
  4. Antidepressants
  5. Antiarrythmics
  6. Alpha-2 agonists
  7. Local anesthetics
  8. Adjuvants
  9. Steroids
  10. Miscellaneous

Algorithm for Pain Management:
WHO released the analgesic ladder for relief of cancer pain. This advice is applicable, not only for cancer patients with pain, but also for all patients with either acute or chronic pain who require analgesics[i]. The cornerstone of the WHO document rests on 5 simple recommendations for the correct use of analgesics to make the prescribed treatments effective.
The 5 points for the correct use of analgesics are as follows:

  1. Oral administration of analgesics whenever possible.
  2. Analgesics should be given at regular intervals.
  3. Analgesics should be prescribed according to pain intensity as evaluated by a scale of intensity of pain.
  4. Dosing of pain medication should be adapted to the individual. There is no standardized dosage in the treatment of pain. Every patient will respond differently. The correct dosage is one that will allow adequate relief of pain.
  5. Analgesics should be prescribed with a constant concern for detail

WHO Ladder:
This analgesic ladder can be used in a bidirectional fashion: the slower upward pathway for chronic pain and cancer pain, and the faster downward direction for intense acute pain, uncontrolled chronic pain, and breakthrough pain
who-ladder
Adjuvant analgesics are drugs which were not originally for pain but rather for other conditions but have been found to be effective in difficult to manage pain, particularly neuropathic pain. They are a diverse group of drugs that includes

  1. Steroids
  2. Anxiolytics Eg: Benzodiazepines
  3. Antidepressants Eg: TCAs
  4. Hypnotics
  5. anticonvulsants, antiepileptic-like gabapentinoids Eg: gabapentin, pregabalin
  6. membrane stabilizers, sodium channel blockers Eg: lignocaine
  7. N-methyl-d-aspartate receptor antagonists Eg: Ketmine

Adjuvant medications can be added at every step of the ladder.
At every step of the analgesic ladder non-opioid analgesics form the basis of the pain management. Paracetamol and NSAID (if not contraindicated) should always therefore be prescribed with opioid analgesia (weak or strong). This is known as multi-modal analgesia and is the concept that pain is best managed, not by a single drug or therapy, but by combinations, which maximise efficacy whilst keeping side-effects low. Evidence has demonstrated that when this happens pain relief is better, smaller amounts of pain killers are needed and fewer side effects occur.

To Summarise with examples:
Analgesic Ladder for Acute and Chronic Pain
STEP 1

  1. Paracetamol 1g qds.
  2. NSAIDs such as ibuprofen, piroxicam etc.
  3. Consider Non-drug Treatments eg psychotherapy, acupuncture, physiotherapy

STEP 2

  1. Medication in STEP 1, plus
  2. Consider adding weak opioids, such as tramadol or codeine phosphate.

If after these steps the pain has not settled, consider:

  1. Whether the pain is neuropathic
  2. Referral to a multi-disciplinary Pain Clinic or another specialist.

Why Multidisciplinary Treatment:
Interdisciplinary treatment care addresses more than the physical pathology.
Chronic pain comprises a range of interdependent variables including biologic, cognitive, affective, behavioral, and social factors. Recent clinical studies have demonstrated the efficacy and cost benefits of interdisciplinary pain management programs.
Eg: Chronic low back pain is a complex phenomenon which includes biological, social and psychological aspects, all of which should be addressed in a treatment program.
This should include pain relief by conservative or interventional methods. After adequate pain relief, attention is paid to:

  1. increasing the physical abilities of the patients (ie flexibility, strength and endurance)
  2. increasing patients’ knowledge and the use of body mechanics and back protection techniques
  3. Decreasing medication-intake
  4. Decreasing dependency on the medical community
  5. Improving patients’ own positive coping skills and levels of emotional control
  6. Increasing the patient’s activity level at home
  7. Facilitate a return to work.

Referral Guidelines: When to refer to Pain Clinic:

  1. Uncontrolled cancer pain
  2. Severe neuropathic pain syndromes, such as trigeminal neuralgia, central post-stroke pain and phantom limb pain
  3. Cases where delay in getting appropriate treatment may be detrimental Eg: complex regional pain syndromes.
  4. Acute sciatica
  5. Where significant disability, distress or loss of work is due to pain
  6. Degenerative disease when surgery is not appropriate eg: OA.
  7. Where simple interventions have not been successful.

Nerve Blocks for Pain Relief:

A nerve block is the interruption of signals traveling along a nerve, usually for the purpose of pain relief.
Role of Nerve Blocks: Different kinds of nerve blocks are used for different purposes.

  • Specific nerve blocks are used to treat painful conditions. Such nerve blocks contain local anesthetic that can be used to control acute pain. Eg Acute pain services like epidural analgesia after surgery
  • Diagnostic nerve blocks are used to determine sources of pain. These blocks contain a anesthetic with a known duration of relief. Eg Diagnostic block for radicular pain ( root block), sympathetic pain (Stellate Ganglion, lumbar sympathetic blocks), Medial Branch blocks for facet join pain, trigeminal nerve blocks etc
  • Therapeutic nerve blocks eg: Epidural steroid injections for radicular pain, RF ablation of Medial branch, Stellate ganglion, Post Herpetic Neuralgia, etc
  • Nerve blocks can be used, in some cases, to give long term relief in post- surgery pain states eg: post hernia surgey pain, FBSS
  • Sympathetic nerve block: is performed to determine whether pain is mediated by the sympathetic system & to treat symptoms due to it
  • A neurolytic block (deliberate temporary damage to nerve fibers) produces blocks that may persist for weeks, months or indefinitely Eg Coeliac plexus block for upper GI cancer pain, Superior Hypogastric plexus block for pelvic pain, etc

Non-Parmacological Treatments:

  1. Physiotherapy has great potential benefit, particularly for patients who suffer from musculoskeletal pain. However, the assessment must be carried out by a physiotherapist with a good understanding of pacing and the importance of a very gradual programme. Patients with chronic musculoskeletal pain frequently run into difficulties if rehabilitation programmes are too ambitious for their needs. Exercise also improves mood, promotes socialisation, inherently provides pain relief and acts as a distracter from pain or other negative emotional experiences.
  2. Occupational Therapy: evaluation process includes a detailed history, range of motion, and strength assessment. Deficits in grip and pinch strength as well as coordination limit a person’s ability to perform activities of daily living such as opening jars, turning a key, and wearing clothes. Pain can make some tasks undoable or take much longer to perform, limiting the patient’s ability to complete independent self-care. The occupational therapist actively involves patients by helping them understand and learn how to manage their disease.
  3. Accupuncture: New evidence shows that acupuncture is useful for Back pain[iii]. This is the most commonly reported use, followed by joint pain, neck pain, headache, postoperative dental pain, carpal tunnel syndrome, fibromyalgia, low-back pain, menstrual cramps, myofascial pain, osteoarthritis, and tennis elbow[iv]. Recently, it has also been shown to be helpful in cancer lymphedema[v]
  4. Psychotherapy: patients require an approach that allows them to talk about their pain and feel supported while simultaneously being motivated to develop a productive life.
  5. Yoga: is helpful by increasing Self-awareness & increasing relaxation. This approach uses respiration, increased self-understanding and self-acceptance and hence there is a changed context of pain, increased control, life style improvements and reduced pain.
  6. Group Therapy
  7. Biofeedback– especially for CRPS, Phantom limb pain syndromes

REFERENCES:

[i]Organisation W. Analgesic Ladder. World Health Organization; 1986.

[ii]Schmerz. 1996 Aug 26;10(4):190-203. [Multidisciplinary treatment program for chronic low back pain, part1. Overview] [Article in German] Hildebrandt J, Pfingsten M, Franz C, Saur P, Seeger D.

[iii]Furlan A, Tulder M, Cherkin D et al. Acupuncture and dry needling for LBP: an updated systemic review within the framework of the cochrane collaboration. Spine 2005;30(8):944-963

[iv] Gunn CC, Milbrandt WE., Tennis elbow and the cervical spine- On Mod Assoc 1978;!   14:803-825.

[v] Cassileth BR, Van Zee KJ, Chan Y, et al. A safety and effi cacy pilot study of acupuncture for the treatment of chronic lymphoedema. Acupunct Med 2011;29:170–2