IC6 Supportive and Palliative Care (Pain mgmt)

Question 1

Briefly describe the 3 steps in the pain ladder

Answer 1

• Step 1 (pain persisting or increasing) → non-opioid +/- adjuvant
• Step 2 (pain persisting or increasing → opioid for mild to moderate pain +/- non-opioid +/- adjuvant
• Step 3 (freedom from cancer pain) → opioid for moderate to severe pain +/- non-opioid +/- adjuvant

Question 2

What is a good guiding percentage of round-the-clock scheduled doses to give, using PRN opioid doses as a baseline?

Answer 2

Generally, add 50% to 100% of PRN usage to around the clock scheduled doses

i.e. if patient usually requires 100mg of X as PRN management, consider changing to 150-200mg LA of X, while maintaining 100mg X PRN

Question 3

What percentage of rescue PRN dosing should account for daily opioid requirement?

Answer 3

10-20%

Question 4

Why are opioid conversion tables not always the most reliable?

Answer 4

Most of these equivalent doses are based on single dosing because it is hard to recruit chronic pain patients to study their pain

Also the conversion is not bidirectional

Question 5

What makes morphine a convenient opioid?

Answer 5

Morphine syrup is not considered a CD in Singapore

Question 6

What condition should be flagged out when considering morphine usage and why?

Answer 6

Kidney failure
The active morphine-6-glucuronide is renally eliminated

Question 7

Comment on the half life of fentanyl

Answer 7

it is very short

Question 8

What are the two possible fentanyl patchdosing conversions?

Answer 8

Durogesic PI says:
3.6mg PO morphine equivalent to 1mcg/hr fentanyl patch

NCCN guideline says:
2mg PO morphine equivalent to 1mcg/hr fentanyl patch

Question 9

What are some patient counselling points for fentanyl patches?

Answer 9

1. do not apply on broken skin
2. avoid taking noontime walks (hot)
3. try to be around people who can look out for you
4. if you experience episodes of nodding off or slow breathing, take off the batch

Question 10

Comment on the onset and time to steady state for fentanyl? How does this influence dosing?

Answer 10

onset is slow (abt 6-8h before any effect)
time to steady state is long (2-3 days for full effect)

therefore usually dosed q72h

Question 11

Which patient group is methadone usually reserved for

Answer 11

overdose patients or drug addicts

Question 12

What effect does methadone have (MOA) that makes it unique?

Answer 12

μ-agonist
also has effects on NMDA

Question 13

Comment on the half life of methadone and the risks associated with it

Answer 13

Very long, therefore risk of accumulation

Question 14

Where is ketamine usually used in hospitals? Where else is it used in pain management?

Answer 14

in the operating room as an anesthetic
may be useful for opioid hyperalgesia (paradoxical reaction where patients become more sensitive to pain)

Question 15

What should be taken note of with regards to other drugs when using ketamine?

Answer 15

Ketamine can potentially lower opioid tolerance

Because it can interact with other opioids and make them supercharged, baseline opioid doses must be drastically decreased (by 50% or more)

Question 16

What are the prominent side effects of ketamine?

Answer 16

nightmares, insomnia

Question 17

Briefly describe opioid tolerance

Answer 17

experience of reduced response to medication
requiring more opioids to experience the same effect

Question 18

Briefly describe opioid dependence

Answer 18

body adjusts normal functioning around regular opioid use
unpleasant physical symptoms occur when the medication is stopped

Question 19

Briefly describe opioid addiction or opioid use disorder (OUD)

Answer 19

attempts to cut down or control use are unsuccessful or when use results in social problems and a failure to fulfil obligations at work, school or home

Question 20

What are the three main areas where the CDC Clinical Practice Guidelines for Prescribing Opioids for Pain are not applicable to?

Answer 20

1. pain related to sickle cell disease
2. cancer-related pain
3. palliative care of end-of-life care

Question 21

What are guidelines 1 and 2 (on non-opioids)

Answer 21

1. Non-opioid therapies are at least as effective as opioids for many common types of acute pain
2. Non-opioid therapies are preferred for subacute and chronic pain

Question 22

What are guidelines 3 to 6 (initiating, dosage, changing, quantity)

Answer 22

3. When initiating, prescribe immediate-release opioids
4. Prescribe at the lowest effective dosage and avoid increasing dosage above levels likely to yield diminishing returns in benefits relative to risks
5. Exercise care when changing opioid dosage
   
   • Optimise non-opioid therapy while continuing opioid therapy
   • If benefits do not outweigh risks, gradually taper
6. Prescribe no greater than the quantity needed

Question 23

What are guidelines 7 to 12 (evaluation, evaluation, monitoring, testing, DDI, OUD)

Answer 23

7. Evaluate benefits and risks early and regularly
8. Evaluate and discuss opioid-related harms and mitigation steps if needed
9. Drug-monitoring program (PDMP)
10. Consider the risks and benefits of toxicology testing
11. Exercise caution when combining opioids with benzodiazepines and other CNS depressants
12. Use evidence based medicine to treat OUD

Question 24

What are some possible adjuvants to pain management? (5)

Answer 24

GABA-acting anticonvulsants (pregabalin, gabapentin)
SNRIs, tramadol, lidocaine patches

Question 25

What effect does tramadol have?

Answer 25

μ-agonist and a serotonin reuptake inhibitor

some combined effect for neuropathic pain

Question 26

What are the three main end-of-life syndromes

Answer 26

dysnpea
secretions
agitation and delirium

Question 27

What is the main treatment considered for dyspnea? In what cases should it not be used and why?

Answer 27

Non-pharm: oxygen therapy
CI with previous bleomycin chemotherapy (increases risk of pulmonary toxicity)

Question 28

What are the two main treatment considered for secretions (drooling)?

Answer 28

Glycopyrrolate (exempt)
Anticholinergics (if already indicated)

Question 29

When are antipsychotics considered for agitation and delirium?

Answer 29

last resort, for underlying condition
atypical antipsychotics like quetiapine are better

Question 30

What causes should be taken note of when handling agitation and delirium?

Answer 30

medication related causes
find alternatives or consider deprescribing

Question 31

How can bowel obstructions be dealt with?

Answer 31

Pancreatic enzymes (crushed) to unclog tubes

Question 32

What are 5 other less common end-of-life syndromes?

Answer 32

anorexia/cachexia
persistent nausea
chronic diarrhea/constipation
insomnia/over-sedation
wound care or pressure ulcers