Pain

Question 1

Risk factors for poor outcomes in back pain

Answer 1

fear avoidance
Catastrophising
Anxiety - psychological vulnerability

Question 2

Difference between nocebo and placebo

Answer 2

Placebo leads to positive outcome.
Nocebo leads to negative outcome

Question 3

What reduces CPSP in breast surgery

Answer 3

PVB, local infiltrartion, IV lignocaine

Question 4

Can gabapentinoids prevent CPSP

Answer 4

Pregabalin reduces incidence of chronic post surgical neuropathic pain only.

Gabapentin no demonstrated effect

Question 5

Does alcohol consumption increase the risk of paracetamol toxicity

Answer 5

no, hepatotoxicity is very rare.

Question 6

Which NSAIDs have shown to increase bleeding risk

Answer 6

Aspirin in adults and children.
Ketoralac only in adults

Question 7

How does rofecoxib increase CV adverse events like myocardial infarction?

Answer 7

Selective blocking of COX-2, reducing prostaglandin production but preserves thromboxane A2, which is a vasoconstrictor and stimulus of platelet aggregation

Question 8

Is parecoxib used in cardiac surgery

Answer 8

no, increases incidence of CV and cerebrovascular effects

Question 9

Which NSAIDs increase the risk of anastomotic leak?

Answer 9

Non-selective NSAIDs
Not coxib

Question 10

What drugs have evidence as pre-emptive analgesia?

Answer 10

Paracetamol and epidural

Question 11

What drugs have evidence as preventive analgesia

Answer 11

Epidural, regional, systemic LA for CPSP
Ketamine

Question 12

Does pre-op education in analgesia lead to a reduction in analgesic requirements?

Answer 12

no, but it reduces pre-op and post-op anxiety

Question 13

What are the options to attenuate remifentanil hyperalgesia?

Answer 13

Propofol, ketamine, pregabalin, nitrous oxide use
Gradual tapering of Remi dose.

Question 14

Options to treat opioid-induced pruritus?

Answer 14

naloxone, naltrexone, droperidol, nalbuphine, ondansetron

Question 15

what is the more reliable way to detecting early opioid-induced ventilatory impairment?

Answer 15

assessment of sedation

Question 16

What is the ceiling dose of intrathecal morphine?

Answer 16

300microg
Any more = increase risk of respiratory depression

Question 17

What’s the evidence of IV lignocaine in breast surgery?

Answer 17

Does not improve pain score

Lower acute opioid consumption, less CPSP at 3 and 6 months.

Question 18

what are the rare but serious side effects of nitrous oxide?

Answer 18

Neurotoxicity: spinal cord degneration, myelopathy, demyelinating polyneuropathy

Anaemia from B12 inactivation

Question 19

Pharmacological options for neuropathic pain

Answer 19

TCA, SNRI, SSRI
Gabapentinoids
Atypical opioids

Question 20

What are the different types of CRPS?

Answer 20

Type 1, accounts for 90% of cases, no evidence of neural damage
Type 2, evidence of neural damage

Question 21

Describe the Budapest criteria for CRPS

Answer 21

1. Continued pain disproportional to injury
2. Display 1, in 3 out of 4 categories, both for self-reporting symptom, and objective examined signs.
   –> Sensory (allodynia, hyperalgesia)
   –> vasomotor (temperature asymmetry, skin colour change)
   –> Sudomotor (oedema, sweating)
   –> Motor or trophic (nail/hair growth change, decrease range of motor function, motor weakness).
3. Exclude other causes

Question 22

Pharmacological treatments of CRPS?

Answer 22

Methylpred 100mg/d, reducing by 25mg/d every week
Bisphosphonate for 8 weeks
Ketamine, lignocaine, capsaicin, A2 agonist

Question 23

Benefit of opioid PCA vs. conventional regimen

Downside?

Answer 23

Higher patient satisfaction
Better analgesia
Aside from below, no diff in other opioid related SE.

Higher opioid consumption, higher incidence of pruritus.

Question 24

Downside of adding a background opioid infusion to PCA?

Answer 24

increases OIVI
does not improve pain relief or sleep or reduce the number of PCA demands

Question 25

What's the most common problem related to PCA?

Answer 25

operator error

Question 26

Does continuous regional catheter prevent phantom limb pain?

Answer 26

No preventive effect on phantom limb pain. It provides post-op analgesia.

Question 27

Which drugs reduce phantom limb pain?

Answer 27

Morphine, gabapentin, ketamine Calcitonin when used acutely <7 days post amputation

Question 28

Non-pharmacological treatments of phantom limb pain?

Answer 28

Mirror therapy, sensory discrimination training, motor imagery - aiming at cortical reorganisation.

Question 29

what are the four operations associated with higher risk of CPSP

Answer 29

Thoracotomy, breast, hysterectomy, herniotomy

Question 30

Typical dose of dexmedetomidine?

Answer 30

0.5mic/kg bolus, over 10 mins, followed by 0.5mic/kg/hr

Question 31

When would surgical fixation be indicated in rib fractures?

Answer 31

≥3 fractured ribs surgical management decreases incidence of pneumonia, need for tracheotomy, reduce duration of ventilation, ICU and hospital stay

Question 32

what drugs reduce the incidence of sickle cell vase-occlusive crisis?

Answer 32

hydroxyurea, zinc

Question 33

Treatment of tension type headache?

Answer 33

Acupuncture Paracetamol + ibuprofen Metoclopramide, chlorpromazine Caffeine/aspirin

Question 34

How does sumatriptan work?

Answer 34

inhibition of vasoactive neuropeptides -> vasoconstriction

Question 35

Treatment of pain for Guillain-Barré syndrome?

Answer 35

Plasma exchange Carbamazepine and gabapentin Paracetamol, ibuprofen Ketamine to reduce opioid doses

Question 36

Why do patients with OSA have an increased risk of post-op respiratory complications?

Answer 36

1. Increased upper airway collapsibility and obstruction 2. Decreased central drive to hypoxaemia and hypercarbia 3. Increased sensitivity to opioid and heightened pain sensitivity

Question 37

What's the indication of naltrexone in opioid tolerance?

Answer 37

Prevention of relapse It does not prevent withdrawal, like methadone or buprenorphine

Question 38

When should you stop naltrexone before surgery?

Answer 38

24 hours at least, but ideally 72 hours.

Question 39

What's a validated opioid withdrawal scale?

Answer 39

COWS - clinical opioid withdrawal scale Total scoring range of 0-48 >36 = severe withdrawal Components include pulse rate, sweating, pupil size, restlessness, tremor, GI upset... .

Question 40

IV dexamethasone - what's the evidence of its use in children undergoing tonsillectomy

Answer 40

Reduction of pain post surgery Does not increase overall risk of bleeding post tonsillectomy but increases the risk of reoperation for bleeding