Introduction Summary At the end of this course, you will be able to: 1.Understand the importance of treating pain 2.Recognize, assess and treat different types of pain 3.Identify and address barriers where you work
What is Pain? CC BY-NC-SA: This work is licensed under a Creative Commons Attribution-NonCommerical-ShareAlike 3.0 License.
What is Pain? Aims To define pain To give examples of pain
What is Pain? Group discussion – Think of a patient / friend / relative who had pain. – How did the person describe the pain? – How was it treated?
What is Pain? International Association for the Study of Pain – Pain is "an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. What does this mean? Are there any other definitions?
What is Pain? Unpleasant Emotions are important The cause is not always visible Pain is what the patient says hurts.
What is Pain? Summary Pain is an unpleasant sensory and emotional experience Pain is what the patient says hurts!
Why Should We Treat Pain? CC BY-NC-SA: This work is licensed under a Creative Commons Attribution-NonCommerical-ShareAlike 3.0 License.
Why Should We Treat Pain? Aims To understand the reasons for treating pain To understand the benefits for the patient, family and society
Case 1 Mr T is a 29-year-old man with a fast growing mouth cancer that has spread to his bones. He has severe face pain. He is expected to die within 6 months and the surgeons do not want to operate. He is married with two children, aged 11 and 8 Why should we treat his pain?
Case 2 Mrs G is a 54-year-old woman who has just had a laparotomy for bowel obstruction. You see her on the surgical ward soon after the operation. She appears to be in pain. Why should we treat her pain?
Why Pain Matters For the patient – Physical Suffering, poor sleep, decreased appetite Medical complications (e.g. heart attack, pneumonia) – Psychological Depression, anxiety
Why Pain Matters For the family – Unable to function as part of the family (e.g. as a father / mother) – Lost income For society – Greater health costs (e.g. delayed hospital discharge) – Unable to contribute to the community
Advantages of Treating Pain For the patient – Fewer physical and psychological problems – Greater dignity (esp. cancer pain) For the family – Able to function as part of the family – Able to provide for family For society – Lower health costs
Why Should We Treat Pain? Summary Treating pain is the humane thing to do! Treating pain has many benefits – For the patient – For the family – For society
Classification of Pain CC BY-NC-SA: This work is licensed under a Creative Commons Attribution-NonCommerical-ShareAlike 3.0 License.
Classification of Pain Aims To classify types of pain To understand that treatment depends on the pain type
Classification of Pain Not all pain is the same! Three main questions: 1.How long has the patient had pain? 2.What is the cause? 3.What is the pain mechanism?
Classification of Pain DurationAcute Chronic Acute on chronic CauseCancer Non-cancer MechanismNociceptive (physiological) Neuropathic (pathological)
Acute versus Chronic Acute – Pain of recent onset and probable limited duration Chronic – Pain persisting beyond healing of injury – Often no identifiable cause – (Pain lasting for more than 3 months)
Cancer versus Non-Cancer Cancer pain – Progressive – May be mixture of acute and chronic Non-cancer pain – Many different causes – Acute or chronic Can you give examples?
Nociceptive Pain Obvious tissue injury or illness Physiological pain Description – Sharp ± dull – Well localised Can you give examples?
Neuropathic Pain Nervous system damage or abnormality Pathological pain Tissue injury may not be obvious Description – Burning, shooting ± numbness, pins and needles – Not well localised Can you give examples?
Acute Non-Cancer Pain Examples – Fracture, appendicitis Symptom of tissue injury or illness Useful Usually nociceptive Occasionally neuropathic (e.g. sciatica)
Chronic Non-Cancer Pain Examples – Headache, back pain Usually no obvious injury Not useful Complex, may be mixed nociceptive and neuropathic Does not respond to usual drug treatment
Cancer Pain Examples – Oral cancer, uterine cervical cancer Features of acute and chronic pain – May be acute on chronic Often mixed nociceptive and neuropathic pain Usually gets worse over time if untreated
Pain What the patient says hurts. What must be treated. Injury Beliefs/concerns about pain Psychol. factors anxiety/anger/depression Cultural issues Language, expectations Other illnesses Coping strategies Social factors e.g. family, work Nociception is not the same as pain! Modified from Analgesic Expert Group. Therapeutic Guidelines 2007
Physiology 4 steps: – Periphery – Spinal cord – Brain – Modulation We will look at each step
Periphery Tissue injury Release of chemicals Stimulation of pain receptors (nociceptors) Signal travels in Aδ or C nerve to spinal cord
Spinal Cord Dorsal horn is the first relay station Aδ or C nerve synapses (connects) with second nerve Second nerve travels up opposite side of spinal cord
Brain Thalamus is the second relay station Connections to many parts of the brain – Cortex – Limbic system – Brainstem Pain perception occurs in the cortex
Modulation Descending pathway from brain to dorsal horn Usually decreases pain signal
Why is pain physiology important? Many factors affect how we feel pain. – Psychological factors are very important. Different treatments work on different parts of the pathway. – More than one treatment may be needed.
Neuropathic Pain Pathological pain Abnormality of: – Peripheral nerves – Spinal cord or brain Needs to be treated differently
Neuropathic Pain Peripheral – Damaged nerves (e.g. trauma, diabetes) – Abnormal firing of nerves Central – Changes in wiring – Abnormal firing – Loss of modulation How do patients describe their pain?
Pain Physiology and Pathology Summary Many factors affect how we feel pain. Different treatments work on different parts of the pain pathway. Neuropathic pain is pathological pain and needs to be treated differently.
Pain Treatment Overview CC BY-NC-SA: This work is licensed under a Creative Commons Attribution-NonCommerical-ShareAlike 3.0 License.
Pain Treatment Overview Aims To discuss non-drug and drug treatments where you work To classify pain treatments
Pain Treatment Group discussion – What non-drug treatments are available where you work? – What drug treatments are available where you work?
Pain Treatment Overview Summary Both non-drug and drug treatments are important. Different treatments work on different parts of the pain pathway. Analgesics can be classified into simple analgesics, opioids and other drugs.
Pain Drugs CC BY-NC-SA: This work is licensed under a Creative Commons Attribution-NonCommerical-ShareAlike 3.0 License.
Pain Drugs Aims To summarise the major advantages and disadvantages of important drugs To discuss drug addiction
Paracetamol (Acetaminophen) Advantages – Cheap, safe – Can be given orally or rectally – Good for: Mild pain (by itself) Mod-severe pain (with other drugs) Disadvantages – Liver damage in overdose
Anti-Inflammatory Medicines Aspirin, ibuprofen Advantages – Cheap, generally safe – Good for nociceptive pain Best given regularly with paracetamol Disadvantages – Gastrointestinal and renal side effects
Codeine Advantages – Cheap, safe – Good for mild-moderate acute nociceptive pain Best given regularly with paracetamol Disadvantages – Constipation – Not good for chronic pain – Myths about addiction
Opioids and Addiction Group discussion – Do opioids cause addiction? – Would this stop you giving opioids to a patient who has pain?
Opioids and Addiction Pain is sometimes poorly treated because of concerns about addiction. Addiction is very rare in: – Acute pain – Cancer pain Addiction is more likely in chronic non-cancer pain.
Morphine 1 Advantages – Cheap, generally safe – Can be given orally, IV, IM, SC – Effective if given regularly – Good for: Mod-severe acute nociceptive pain (e.g. post-op pain) Chronic cancer pain
Morphine 2 Disadvantages – Constipation – Respiratory depression in high dose – Myths about addiction – Regulations about use
Pethidine Advantages – Cheap – Can be given orally, IV, IM – Can be good for severe acute nociceptive pain Disadvantages – Must be given more often than morphine – Breakdown product (norpethidine) can cause convulsions – Not good for chronic pain
Amitriptyline Increases descending inhibitory signals Advantages – Cheap, safe in low dose – Good for neuropathic pain – Also treats depression, poor sleep Disadvantages – Anti-cholinergic side effects (glaucoma, urinary retention)
Anti-Epileptic Drugs Carbamazepine (Tegretol) Sodium valproate (Epilim) Membrane stabilisers – Reduce abnormal firing of nerves Good for neuropathic pain
Entonox (N 2 O/O 2 ) Advantages – Fast onset / fast offset – Good for: Labour pains Short painful procedures (e.g. dressing changes) Disadvantages – Need cylinder and mask
Drug Treatments Acute noci mild Acute noci severe Acute neuro Chronic non- cancer Chronic cancer Paracetamol ++++++++ NSAIMs ++ +±± Codeine +++± Morphine +++++-+++ Amitriptyline --++ Carbamazepine --++++
Pain Drugs Summary Pain can be treated with relatively cheap and safe drugs. Opioid addiction is rare in acute or cancer pain.
Barriers to Pain Treatment CC BY-NC-SA: This work is licensed under a Creative Commons Attribution-NonCommerical-ShareAlike 3.0 License.
Barriers to Pain Treatment Aims To understand some of the reasons why pain may not be treated adequately To think about some solutions
Barriers to Pain Treatment Group Discussion – Pain is often not treated as well as it could be. What are some of the reasons for this? Patients Drugs Health workers System issues – What are the main barriers where you work? – What can be done about these barriers?
Barriers to Pain Treatment Summary There are many reasons why pain is not treated as well as it could be. Important barriers are attitudes, lack of staff and lack of drugs. How can YOU overcome these barriers where you work?
Basic Approach to Pain Management CC BY-NC-SA: This work is licensed under a Creative Commons Attribution-NonCommerical-ShareAlike 3.0 License.
Basic Approach Aims To give a simple framework for managing patients with pain To illustrate the use of this framework for different types of pain
Approach to Pain Assess Make a pain diagnosis! – Acute or chronic? – Cancer or non-cancer? – Nociceptive or neuropathic? Look for neuropathic features: – Burning or shooting pain – Phantom limb pain – Other features (pins and needles, numbness)
Approach to Pain Assess Are there other factors? – Physical factors (other illnesses) – Psychological and social factors Anger, anxiety, depression Lack of social supports
Approach to Pain Treat Non-Drug Treatments – RICE Rest, ice, compression, elevation of injuries – Nursing care – Surgery, acupuncture, massage etc – Psychological Explanation and reassurance Input from social worker / pastor
Approach to Pain Treat Drug Treatments – Nociceptive Pain – Mild Paracetamol (± NSAIM) – Moderate Paracetamol (± NSAIM) + codeine – Severe Paracetamol (± NSAIM) + morphine
Approach to Pain Treat Drug Treatments – Neuropathic Pain – Traditional drugs may not be as useful – Use other drugs early Amitriptyline Carbamazepine Dont forget non-drug treatments
Approach to Pain Example 1 Mr D is a 32-year-old man who caught his right hand in a piece of machinery at work and now has a large open wound with several broken bones. How would you manage his pain?
Approach to Pain Example 2 Jon is an 8-year-old boy with probable appendicitis. He is in the Emergency Department and will have to wait several hours for an operation. How would you manage his pain?
Approach to Pain Example 3 Miss B is a 24-year-old woman who has a two year history of severe headache. She was seen at the regional hospital 6 months ago and was told that there was nothing wrong inside her head and she was going to have to live with the pain. How would you manage her pain?
Approach to Pain Example 4 Maria is a 12-year-old girl with burns to her chest and abdomen. She needs dressing changes every 2-3 days. How would you manage her pain?