Management of Pain

Question 1

Ex findings when assessing pain (5)

Answer 1

Allodynia: non-painful stimuli feel painful after experiencing painful, often repetitive stimuli.

hyperalgesia: painful stimuli exaggerated

tenderness

deformity

inflammation

Question 2

investigating pain (4)

Answer 2

CT
XR
MRI
Bone scan

Question 3

Mx of mild pain (3)

Answer 3

continuous:

• paracetemol 1g QDS
• ibuprofen 400mg QDS

for breakthrough:
-weak opioid: codeine 60mg QDS

Question 4

Mx of moderate to severe pain (2)

Answer 4

continuous:
-co-codamol PO QDS

breakthrough:
-oromorph 5mg PO PRN (max 4hrly)

Question 5

Mx of acute severe pain (4)

Answer 5

IV morphine 10mg+:

• metoclopramide IV
• senna
• sodium docusate

Question 6

Different morphine preparations (4)

Answer 6

PO:

• oromorph: immediate release solution, good for breakthrough
• MST: given 12hrly, slow release.
• sevredol: immediate release tablets

SC:
-morphine sulphate, diamorphine

Question 7

Alternative strong opioids (5)

Answer 7

Fentanyl:

• patch
• takes 24hrs to reach steady state
• oromorph for breakthrough
• avoid in opioid-naiive pts due to risk of toxicity
• good if liver impairment and poor swallow.

oxycodone:

• used 2nd line if unable to tolerate morphine
• PO/IV/SC/rectal suppository

Buprenorphine patches

hydromorphone

methadone

Question 8

SEs of morphine (7)

Answer 8

nausea/vomitting
confusion
drowsiness
resp depression
constipation
toxicity
tolerance, physical dependence and addiction

Question 9

Features of morphine toxicity (5)

Answer 9

Confusion
Hallucinations
myoclonic jerks
agitation
resp depression and LOC

(caused by high dose, renal/hepatic impairment, change in routine, response to adjuvant/non-opioid therapies)

Question 10

DDx for morphine toxicity (3)

Answer 10

hypercalcaemia
brain mets
sepsis

Question 11

Features and Mx of severe opioid toxicity (2)

Answer 11

RR<8, cyanosis and LOC

Give naloxone 0.4mg every 2-3 mins until resp function returns. NB causes withdrawal.

if mild then lower dose

if moderate, omit next dose and start lower dose.