Anaesthetics & pain

Question 1

Analgesic ladder

Answer 1

Oxycodone > morphine if renal impairment

Do not give NSAIDs in asthma/renal impairment/elderly/pregnant

Neuropathic pain does not respond to opioids

Question 2

Cause of Post-op hypotension?

Answer 2

Common S/E of epidural/spinal anaesthesia

Question 3

Pain assoc w/ renal colic responds well to?

Answer 3

Responds well to PR NSAIDs (diclofenac)

Question 4

Tx for trigeminal neuralgia?

Answer 4

Carbamazepine 1st line for neuropathic pain

Question 5

Diabetic painful neuropathy Mx?

Answer 5

duloxetine

Question 6

General anaesthesia - main aims? Induction? Maintenance?

Answer 6

Main aims:

• Hypnosis - lack of awareness
• Amnesia - forget what happened
• Analgesia - pain Mx
• Areflexia - suppress normal reflexes
• Muscle relaxation (esp around pharynx for safe intubation)

Induction: transition from awake to asleep (count down from 100), agents work by enhancing GABA activity (brain inhibition)

• IV (longer operations) - propofol, thiopentone, etomidate
• Inhalation - sevoflurane, nitrous oxide

Maintenance: keep patient unconscious

• IV - propofol (also anti-emetic so good if get post-op nausea/vomiting)
• Inhalation - sevoflurane, isoflurane, halothane

Question 7

What is the purpose of cricoid pressure as a patient is put to sleep for surgery? What patients need this?

Answer 7

It prevents the passage of gastric contents into the airway in patient who has not fasted/has abdominal problems

Question 8

Treatment of neuropathic/nerve compression pain?

Answer 8

Amitryptiline

(other 1st line options - pregabalin/gabapentin/duloxetine)