Supportive and Palliative Care (Pain) Flashcards
What are the pain managements according to WHO Pain ladder?
Step 1: non-opioid +/- adjuvant
Step 2: opioid for mild to mod pain +/- non-opioid +/- adjuvant
Step 3: opioid for mod to sev pain +/- non-opioid +/- adjuvant
Is morphine a controlled drug in SG?
No, hence it is conveniently used
What is the active metabolite of morphine?
Morphine-6-glucuronide
Is morphine renally or hepatically cleared
Renal -> must be careful in cancer pts who often have end organ failure i.e kidney failure
SE of opioids
Somnolence
Respiratory depression
Constipation
How to determine the prn dose to give from the chronic dose
Add 50% to 100% of prn usage to around the clock scheduled doses
Rescue prn doses = 10% - 20% daily opioid requirements
Is fentanyl stronger than heroin and morphine?
Yes, up to 50x stronger than heroin and 100x stronger than morphine
Fentanyl PK (half life, onset, ss)
IV: Very short half life, fast onset, often used in ICU
For patch:
Slow onset: 8-12hr
Steady state slower: Q72hrs for full effect
When is fentanyl patches recommended over other opioids?
When pt is opioid tolerant
Pt cannot swallow
What does opioid tolerant mean?
Can tolerate 60mg morphine PO per day or equivalent
What are some counselling points for fentanyl patch?
Do not put on broken skin/rashes
Do not rub on the patch or expose it to the sun
Do not use it when pt has a fever
When is methadone given?
For opioid withdrawals and to reverse some opioid tolerance
Methadone or fentanyl take longer for full effect?
Methadone (5-7days)
Is ketamine an opioid?
No, it is an anesthetic with some interesting properties in patients with opioid hyperalgesia
What is opioid hyperalgesia?
end of life pts on 80-100mcg/hr fentanyl patch and pain still not controlled.
How does ketamine work?
Ketamine itself has analgesic effect but not potent. It works with opioid to make the opioid “supercharged” so reduces baseline opioid dose.
How much to reduce baseline opioid when initiating ketamine?
> =50%
2 Side effects of ketamine
Nightmares and hallucinations
Difference btw opioid tolerance vs dependence vs addiction
Tolerance: reduced response to medication to require more opioids or higher doses to exp same effect
Dependence: body adjusts normal functioning ard regular opioid use. Unpleasant physical smx occur when medication is stopped
Addiction: Opioid use disorder (OUD) when reducing dose or control use are unsuccessful or when it results in social problems and failre to fulfill obligations at work/sch/home. Often comes after tolerance and dependence.
CDC clinical practice guidelines are not applicable for __?
- management of pain related to sickle cell disease,
- management of cancer-related pain, or
- Palliative care or end-of-life care
…but still has useful principles we can learn from for all situations
What are some considerations when prescribing opioids for pain according to CDC guidelines
- When initiating, prescribe immediate-release opioids
- Prescribe the lowest effective dosage, avoid increasing dosage above levels likely to yield diminishing returns in benefits relative to risks
- Exercise care when changing opioid dosage:
Optimize nonopioid therapies while continuing opioid therapy
If benefits do not outweigh risk, gradually taper - Prescribe no greater quantity than needed
- Evaluate benefits and risks early and regularly
- Evaluate and discuss if needed opioid-related harms and mitigation steps
- Drug monitoring program (PDMP)?
- Consider the benefits and risks of toxicology testing
- Use caution when combining opioids with benzodiazepines and other CNS depressants
- Use evidence based medicine to treat opioid use disorder (OUD)
What are some adjuvants that can be given for pain
- Gaba acting anticonvulsants (more common)
Gabapentin
Pregabalin - SNRIs
- Tramadol
- Lidocaine patches (not common)
End of life syndromes: How to treat dyspnea?
- Non-pharmacologic approaches should be considered
- Oxygen therapy may be helpful in some cases, remember to consider if had previous bleomycin chemotherapy
- Morphine prn is routinely seen prescribed at NUH, titrated to respiratory rate eg. when RR>15-20 PRN
End of life syndromes: How to treat secretions?
Glycopyrrolate (but exempt in SG)
Anticholinergics (but weight toxicities and pt preference)
