Pain management

Question 1

Explain different types of pain

Answer 1

Nociceptive = pain felt by normal/intact nervous system (often by pressure stimulus)

Nociceptive pain can be visceral or somatic

Visceral = from hollow/solid organ (diffuse ache, hard to localise)
Somatic = sharp, localised pain from skin, muscles, bone

Neuropathic = Pain felt by malfunctioning/damaged nervous system (shooting, burning, tingling)

Question 2

Analgesics types and examples of each

Answer 2

Non-opioids = paracetamol, NSAIDs (ibuprofen, naproxen), Cox-2 inhibitors (celecoxib)

Weak opioids = tramadol, codeine phosphate, co-codamol, dihydrocodeine

Strong opioids = fentanyl, morphine, buprenorphine, oxycodone, diamorphine

Adjuvants = antidepressants (amitriptyline, duloxetine), anticonvulsants (gabapentin, pregabalin), benzos- (diazepam, clonazepam), steroids (Dexamethasone), bisphosphonates (pamidronate)

Question 3

When would you use cox-2 inhibitors over NSAIDs and what would you always prescribe when giving either?

Answer 3

When the patient is known to have existing upper GI issues

Always give PPI with NSAIDs or cox-2 inhibitors

Question 4

What is an adjuvant and why are they used?

How long do drugs for neuropathic pain take to work?

Answer 4

Adjuvant analgesic = drug in which primary indication not for pain

Given for pain that is partially/not responsive to opioids e.g. amitriptyline/gabapentin given for neuropathic pain (usually takes around 5 days to kick in)

Question 5

Side effect profile of tramadol vs codeine

Answer 5

Tramadol causes more N&V + anorexia
Codeine causes more constipation

Question 6

What is the WHO ladder?

Answer 6

Step-wise approach to managing pain

Step 1 = non-opioids

Step 2 = weak opioids (have a ceiling dose - so if not working, always step up, don’t switch or increase dose further)

Step 3 = strong opioids

(All 3 steps can be with/without adjuvant)

Question 7

Common and rare side-effects of opioid use

Answer 7

Common Initial:
- Nausea and vomiting
- Drowsiness
- Light-headedness
- Cognitive impairment

Common Continuous:
- Constipation
- Dry mouth

Rare:
- Psychological dependence (rare as opioids serve their use in cancer patients)
- Respiratory depression

Question 8

Potential patient concerns when starting opioids?

Answer 8

Severe side-effects
Addiction
Think they’re near death
They think it is the last resort

Question 9

What types of pain (body areas) respond to what analgesics the best?

Answer 9

Bony mets - NSAIDs, bisphosphonates

Liver pain - steroids, NSAIDs

Question 10

What is break-through pain and how is this managed?