Pain Management In Cancer Flashcards
General principals for symptom management in oncology?
see Pain and prescribing analgesia LEC on BB
Epidemiology of pain in cancer patients
- 30-40% patients with early disease
- 75-90% with advanced cancer
- 65% dying from non-malignant disease
- 1/3 with >2 different pains
- Pain can be controlled in 80% using stepwise approach
What do you need to include in your pain assessment?
BB LEC:
* the impact of the pain on all areas of the patient’s life
* Their understanding of the pain what does it mean to them?
* Any concerns they may have about treatment of the pain
From ox handbook
* detailed history and examination to understand cause i.e. nervre pain doesnt respond to opiods as well
* severity
* nature
* functional deficit
* psychological state
Pain in advanced disease: nature, cause, how it effects the patient
Example of a pain asessment : what are some possible causes of his pain? (think cancer, iatrogenic, other)
Possible causes for his pain would include:
CANCER related:
* chest wall invasion, bone metastases, MSCC
TREATMENT related:
* oesophagitis, local reaction to RT
OTHER:
* CAP, PE pneumothorax, MI, anxiety, musculoskeletal
AR neuro anatomy of pain pathway
What are some different types of pain?
just names for now
- Nociceptive
* somatic
* visceral - Neuropathic
- Mixed (40%)
- Incident
Define nociceptive pain
Nociceptive pain= normal nervous system, identifiable lesion causing tissue damage.
2 types:
Somatic and Visceral
Somatic pain :
Where does it originate from?
how might it be described?
Origin:
* from skin/muscles/bone
Described as:
* sharp, throbbing, well localised
Visceral pain :
Where does it originate from?
how might it be described?
Origin:
* hollows viscus or solids organ
Described as:
* diffuse ache, hard to localise
Define neuropathic pain
How might it be described?
define:
* malfunctioning nervous system; nerve structure is damaged
Described as:
* stabbing, shooting, burning, stinging, allodynia, numbness, hypersensitivity
What is mixed pain
(about 40% pts get)
mixture of Nociceptive and neuropathic pain
What is incident pain?
Pain due to a certain event such as movement, coughing, dressing change
Using analgesics effecitvely. What 3 classes of pain relief do we have?
What are adjuvant / co-analgesics?
what? who should you use for? benefits? cautions?
- Drugs whose primary indications is not for pain
- Consider for pain that is only partially responsive to opioid analgesia
- Can have a significant opioid sparing effect
- be careful as can have some adverse effects e.g. CNS symptoms
What are some examples of adjuvant / co-analgesics?
- Antidepressants:
amitriptyline, duloxetine - Anti-convulsants;
gabapentin, pregabalin - Benzodiazepines:
diazepam, clonazepam - Steroids:
dexamethasone - Bisphosphonates:
for bony pain
What are some drugs indicated for neuropathic pain?
give examples, doses and some SE (BB LEC)
- Amitriptyline:
dose: start 10-25 mg
SE: confusion, hypotensions, caution in CVS disease - Gabapentin
dose: 300 mg TDS over 3/7 - Pregabablin:
dose: 75 mg BD
SE: sedation, tremor, confusions, dizziness, caution in renal impairment)
How long can it take for analgesics for neuropathic pain to work ?
Full beneift can take at least 5/7
may need to be titrated
WHO analgesic 5 principals for effective pain management :
p532 ox hanbook + BB Lec
- By the mouth—give orally whenever possible.
- By the clock—give at fixed intervals to offer continuous relief.
- By the ladder—following the WHO stepwise approach
- For the individual—there are no standard doses for opioids, needs vary. (inidividual dose titration and use adjuvants at any step)
- Attention to detail—communicate, set times carefully, warn of side-effects
WHO pain ladder
Stage 1 (Non-opioids)
- Paracetamol
- Ibuprofen
- Paracetamol + Ibuprogren
Step 2
- Non-Opioids +
- Weak opioid (dihydrocodeine, codeine phosphate, tramadol, co-codamol)
Stage 3
- Non- opioid +
- Opioid (Oxycodone, morphine, fentanyl, diamorphine)
What are some key points to remember when using the WHO pain ladder to manage a pts pain?
(CLUE: reasons to go up and down, drugs that can be opiate sparing, other drugs to help with SE, adjuvants)
pg 532 in oxford handbook of clinical medicine
- Persisting/increasing pain and side-effects inform the decision to step up and step down. Take one step at a time to achieve pain relief without toxicity (except in new, severe pain when step 2 may be omitted).
- Paracetamol (PO/PR/IV) at step 1 may have an opiate-sparing effect, and should ben continued at steps 2 and 3. Stop step 2 opioids if moving to step 3.
- Use laxatives and anti-emetics with strong opioids.
- Adjuvants which can be added at all steps include: NSAIDS, amitriptyline, pregabalin, corticosteroids, nerve block, transcutaneous electrical nerve stimulation (TENs) radiotherapy
What are examples of non-opiod pain relief?
- Paracetemol
- NSAIDS
- COX-2s
Table from BB LEC:
For each type of pain think of:
1. key features
2. response to opiods
Managing pain:
Bone mets often respond to….?
- NSAIDS
- RT (radiotherapy)
- Surgery
Pain management: Liver pain may improve with…?
drug names from BB LEC
Steroids
NSAIDs
What type of pain is often poorly responsive to opiods ?
Neuropathic pain
Successful pain relief involves…?
- Regular and PRN doses
- Titration of dose against effect with no rigid upper limit for strong opioids
- Appropriate time interval between doses
- Sufficient dose to prevent return of pain before next dose is due
- Willingness to give strong opioids early when other analgesics fail
- Early consideration of adjuvants
- Regular review and assessment
- Follow analgesic ladder
- Appropriate explanation/information for patient
Opioids (from weak to strong)
- Codeine
- Co-codamol
- Tramadol
- Morphine
- Diamorphine
- Fentanyl
- Oxycodone
Why are NSAIDs and COX-2 used in cancer?
- Due to inflammatory component common in cancer pain
- COX-2 now preferred unless patient at risk of sudden CV event
NSAIDS vs COX-2 inhibitors for cancer pain
- COX-2 inhibitors are a type of NSAID.
- Unlike traditional NSAIDs, COX-2 inhibitors work in a different way to control inflammation and pain ( just as effective)
- COX-2 inhibitors cause fewer stomach and intestinal problems, such as bleeding and ulcers
NSAID or COX-2: If a patient has no CV or GI risk?
NSAID: ibuprofen or naproxen
NSAID or COX-2: If patient has GI risk but no CV risk ?
COX-2 e.g. celecoxib
NSAID or COX-2: If patient has CV risk but less GI risk?
NSAID e.g. naproxen or ibuprofen
principles of using NSAIDs of COX-2
what need to also prescribe? when need to be cautious?
Prescribe PPI for all
Care in HF exacerbated by ALL
Drug terms in pain relief :
What does the following mean?
IR
SR
TDD
IR = Immediate release
SR = Slow release
TDD = Total daily dose
dose for paracetemol for pain?
- Must be over 50kg for full dose
- 1g- QDS regularly
Side effects of neurophathic painkillers?
- Sedation
- Tremor
- Confusion
- Dizziness
- Be careful if renal impairment (renally excreted- test function before)
** Beware of AKI e.g. due to sepsis
**
Weak opioids (step 2) in cancer care
- Can argue no pharmacological need for weak opioids in cancer pain
- Low dose morphine often provides quicker and better pain relief than weak opioids
- Weak opioids no longer recommended in children (step 2 skipped)
- Examples include:
- Codeine
- Dihydrocodeine
- Tramadol
- Ceiling effect for analgesia – side effect > benefits
What are some key side effects of weak opiods?
- Tramadol is less constipating than codeine/dihydrocodeine
- BUT causes more N&V and anorexia
Strong opiods (step 3) in cancer care
role, SE, examples, prescribing considerations
- Essential drugs in cancer care
- Undesirable SE related to central and peripheral Mu receptors activation (CNS and GI tract)
- Examples
- Morphine
- Oxycodone
- Diamorhinw
- Fentanyl
- Buprenorphine
- Because of wide number of different formulation and brands available, prescribing by brand is encouraged to reduce risk of error/ confusion
Side effects of strong opiods
What are some potential anxities when commencing morphine?
- Addiction
- Tolerance/loss of effectiveness
- The end of the road / Last resort
- Severe side effects
What are some causes of opiod toxicity?
- Dose escalated too quickly
- Renal impairment
- Poor opioid responsive pain but escalated
- Has had intervention to reduce pain (nerve block)
How does opiod toxicity present?
- Pinpoint pupils
- Hallucinations, drowsiness
- Vomiting
- Confusion
- Myoclonic jerks
- Respiratory depression
What drug to you give to manage opiod toxicity?
Naloxone
Lecture: stepping up from maximum dose codeine to morphine
how much equates to?
TDD?
What generally prescribe?
Options for oral morphine?
opiod dose:
how work out TDD
The SR dose?
The Breakthrough dose?
Titration example
Patient taking oramorph 5mg PRN
need 8 PRNS to achieve pain relief
no side effect
titration : patient taking zomorph 30mg BS but still in pain
Need 3 PRN dose a day of oramorph 10 mg
work out TDD, New BD, and new PRN
Titration : patient taking zomorph 120mg BD, still in pain, needing 3 PRN doses of oramorph 40mg with good effect
what is TDD, new BD dose and new PRN
fentanyl: how use?
how long for steady state?
dose?
syringe driver: pt taking morphine 40 mg / 24 hours
they are ALSO needing 5mg SC PRN x 4/24hours
what is new dose for syringe driver to step up?
A cancer patient with severe renal failiure <eGFR 15ml/min is becoming more unwell. Which drug is most appropriate in renal failure ?
- diclofenac
- morphine
- alfentanil
- naproxen
- diamorphine
capsule
Alfentanil
* hepatic metabolism
* short half life - effects susbide more quickly wehn stopped
* suitable for SC syringe driver in renal failure as less likely to accumulate
Patient with extensive bone mets is getting some pain relief from opiods but pain is not adequately controlled. what are further interventions for his bone pain?
capsule
- Radiotherapy
* A single 8 Gray (dose) in one fraction (treatment) has been shown to reduce pain caused by bone metastases. - Zoledronic acid
* reducing skeletal related events. Bisphosphonates work by inhibiting osteoclast-driven bone reabsorption.
- Zoledronic acid
