Dr. Suresh Kumar Institute of Palliative Medicine Kerala, India

Pain definition An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage (INTERNATIONAL ASSOCIATION FOR STUDY OF PAIN) Suresh Addis 2009

A ‘simple’ definition… Pain is what a person says “ it hurts”. Suresh Addis 2009

Pain in cancer Incidence of pain at various stages of cancer disease trajectory is approximately 50% This increases to approximately 80% in advanced cancer Suresh Addis 2009

Pain in cancer Most patients with advanced cancer have two or more types of cancer related pain sometimes with different etiologies Suresh Addis 2009

Pain in cancer 90% of cancer pain could be effectively controlled using the WHO guidelines Cancer pain is often under diagnosed and under treated Suresh Addis 2009

Assessment of pain Inadequate pain assessment is an important contributing factor in the under treatment of pain Suresh Addis 2009

Why assess pain Assess efficacy of therapy Better understanding of pain Encouragement, support Future reference Suresh Addis 2009

Measurement of pain Unidimensional Numeric Rating Scale Verbal Rating Scale Visual Analog Scale Verbal Descriptor scales Faces Pain Rating Scale Suresh Addis 2009

Multidimensional Instruments McGill Pain Questionnaire Brief Pain Inventory Multidimensional Pain Inventory Suresh Addis 2009

Numeric Scale

Suresh Addis 2009 Simple Descriptive Scale

Suresh Addis 2009 Visual Analogue Scale The VAS for Pain severity measurement No Pain Worst Possible Pain The VAS for Treatment Effect No Pain Complete Pain Relief

Suresh Addis 2009 VAS: Coloured Analogue Scale

Classification of Pain PAIN NOCICEPTIVE VISCERALSOMATIC NEUROPATHIC Suresh Addis 2009

Acute & Chronic Pain Acute pain: Well defined temporal pain onset Associated with subjective and objective physical signs Hyper activity of ANS Increased BMR Helps in limiting the damage Suresh Addis 2009

Acute & Chronic Pain Chronic pain: Pain persisting for > 3 months Less well defined temporal onset Adaptation of ANS, lack of objective signs Changes in personality, lifestyle, functional ability No known useful biological purpose Suresh Addis 2009

Causes of Pain in Cancer Directly due to cancer Soft tissue infiltration Bone involvement Nerve infiltration / compression Visceral pain Muscle spasm Suresh Addis 2009

Causes of Pain in Cancer… Due to treatment Surgery Direct Scar Radiotherapy Fibrosis Mucositis Chemotherapy Neuropathy Suresh Addis 2009

Causes of Pain in Cancer… Due to associated factors Pressure sores Constipation Bladder spasm Stiff joints PHN Suresh Addis 2009

Causes of Pain in Cancer… Unrelated causes LBA Trauma Arthritis Angina Emotional factors Suresh Addis 2009

Management of cancer pain: In 90% of patients, analgesia achieved with drug therapy - By mouth - By the clock - By the ladder Suresh Addis 2009

dr ug co nc en tra tio n Time (Roughly take 4 half lives to reach 95% Css ) Steady state plasma concentration (Css) When all the trough and peak concentrations do not vary

WHO Analgesic Ladder Strong opioid + Step 1 Weak opioid + Step 1 Non opioid + adjuvants Suresh Addis 2009 Step 1 Step 2 Step 3

Non Opioids NSAIDs Paracetamol Suresh Addis 2009

NSAIDS : Mode of action suppression of prostaglandin synthesis at sites of tissue injury modulation of the neutrophil intracellular signaling function (  migration of neutrophils to inflammatory sites) Suresh Addis 2009

NSAIDs: Adverse effects GI toxicity Renal toxicity Interference with platelet function Suresh Addis 2009

Use of NSAIDS it is recommended that NSAIDs be used at the lowest effective dose for the shortest duration of time necessary especially in patients over the age of 65 years, those taking oral corticosteroids, and those treated with anticoagulants. Suresh Addis 2009

Opioids The division into weak or strong only for our convenience Weak opioids: Codeine Dextropropoxyphene Pentazocine Tramadol Suresh Addis 2009

Strong opioids Morphine Pethidine Fentanyl Oxycodone Hydromorphone Suresh Addis 2009

Opioid side effects Constipation99% Nausea, vomiting33% Sleepiness, tiredness 33% Urinary hesitancy5% Itching5% Suresh Addis 2009

Signs of overdose Drowsiness Delirium Myoclonus Respiratory depression?? Suresh Addis 2009

Adjuvants To limit the side effects of analgesics Co - analgesics Suresh Addis 2009

Co - analgesics Steroids Anti depressants Anti epileptics Anti arrythmics NMDA receptor antagonists Suresh Addis 2009

Treatment of Cancer pain : Summary Assess properly before deciding on a management scheme Suresh Addis 2009

Social Emotional Spiritual ? Tumour ? Metastases ? Nerve Infiltration ? Constipation ? Gastritis Treatment of Cancer pain : Summary Identify the cause of pain before treatment: Think of multiple causes!!

Treatment of Cancer pain : Summary Decide on the ‘pharmacological strategy’ Work within the WHO Ladder Suresh Addis 2009

Treatment of Cancer pain : Summary Remember supportive measures Combine pain relief with relief from other symptoms emotional and social support Suresh Addis 2009

Pain not responding to WHO ladder Possible causes are The prescriber! The patient! The pain Suresh Addis 2009

Prescriber as a cause for ‘difficult pain’ Are the basic prescribing guidelines being followed? Is the WHO ladder being used properly? Has the dose of opioid titrated up according to clinical response? Is the dose and dosing interval correct? Have co analgesics and other interventions been used appropriately? Suresh Addis 2009

The patient as a cause for ‘difficult pain’ Is the patient taking medication as prescribed? Are there fears/ concerns being addressed? Is there co existing depression? Does the pain have a significant psycho social or spiritual component? Suresh Addis 2009

The nature of pain itself as a cause for difficult pain Is it a neuropathic pain? Is it a colic? Is it a muscle spasm? Is it a pain from an ulcer? Is it incident pain? Suresh Addis 2009

Thank You! Suresh Addis 2009