Pain medicine Flashcards

1
Q

UFH (s/c prophylaxis) - NAB timings

A
  • Wait following dose: 4 hours or normal APTT
  • Wait following block: 1 hour
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Indications for RF therapy

A
  • Trigeminal neuralgia
  • Cervical cordolay
  • Cervicogenic headache
  • Spinal pain
  • Groin pain
  • Orchidalgia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define complex regional pain syndrome

A

A chronic pain disorder characterised by:

  • vasomotor
  • sudomotor
  • trophic
  • inflammatory.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is CRPS Type 1?

A

Symptoms preceded by tissue injury.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the previous name for CRPS Type 1?

A

Reflex sympathetic dystrophy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is CRPS Type 2?

A

Symptoms proceded by major nerve injury

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the previous name for CRPS Type 2?

A

Causalgia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the pathophysiology of CRPS?

A

Unknown. Involves peripheral and central sensitisation and altered sympathetic function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the sensory symptoms of CRPS?

A
  • Burning
  • allodynia
  • hyperalgesia
  • sensory defects in CRPS 2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the autonomic symptoms of CRPS?

A
  • Vasodilatation:
    • Warm
    • erythematous
    • sweaty
  • Vasoconstriction
    • cold
    • dry
    • white
  • Oedema also occurs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the trophic symptoms of CRPS?

A
  • Atrophy of hair, skin and nails
  • Joint stiffness
  • Osteoporosis.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the treatment options for CRPS?

A
  • Physiotherapy
  • Pharmacological
  • Interventional
  • Surgical
  • Psychological
  • Alternative
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the pharmacological treatments options for CRPS?

A
  • Antineuropathic agents
  • Opioids in refractory cases only
  • Corticosteroids
  • Calcitonin
  • Bisphosphonates
  • Free radical scavengers - NAC IV
  • lidocaine infusions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the interventional treatment options for CRPS?

A
  • LA sympathetic block i.e. stellate ganglion block
  • Sympathectomies (RF ablation or surgically)
  • Spinal cord stimulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the surgical treatment options for CRPS?

A
  • Surgical sympathectomy
  • Amputation (reserved for most severe cases)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the physiotherapy treatment options for CRPS?

A

Graduated exercise programmes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the psychological treatment options for CRPS?

A
  • CBT
  • Pain management programmes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the alternative treatment options for CRPS?

A

Acupuncture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the budapest criteria?

A

A diagnostic criteria for CRPS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 4 budapest criteria categories?

A
  1. Sensory
  2. Vasomotor
  3. Sudomotor/Oedema
  4. Motor/Trophic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What constitutes a diagnosis of CRPS on the Budapest Criteria?

A
  1. Symptoms in excess of the original insult
  2. At least 1 sign in 2 different Budapest categories
  3. At least 1 symptom in 3 difference Budapest categories
  4. No other better explanation for the symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the sensory Budapest criteria?

A
  • Allodynia
  • Hyperalgesia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the vasomotor Budapest criteria?

A
  • Temperature
  • Asymmetry
  • Skin colour changes
  • Skin colour asymmetry
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the Sudomotor Budapest criteria?

A
  • Oedema
  • Sweating changes
  • Sweating asymmetry
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the Motor/Trophic Budapest criteria?

A
  • Reduced range of motion
  • Motor dysfunction (weakness, tremor, dystonia)
  • Trophic changes (hair loss, nail changes)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

UFH (IV treatment) - NAB timings

A
  • Wait following dose: 4 hours or normal APTT
  • Wait following block: 4 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

LMWH (s/c prophylaxis) - NAB timings

A
  • Wait following dose: 12 hours
  • Wait following block: 4 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

LMWH (s/c treatment) - NAB timings

A
  • Wait following dose: 24 hours
  • Wait following block: 4 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Danaparoid prophylaxis - NAB timings

A
  • Wait following dose: Avoid (consider anti-Xa levels)
  • Wait following block: 6 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Danaparoid treatment - NAB timings

A
  • Wait following dose: Avoid (consider anti-Xa levels)
  • Wait following block: 6 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Bivalirudin - NAB timings

A
  • Wait following dose: 10 h or normal APTTR
  • Wait following block: 6 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Argatroban - NAB timings

A
  • Wait following dose: 4 h or normal APTTR
  • Wait following block: 6 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Fondaparinux prophylaxis - NAB timings

A
  • Wait following dose: 26 - 42 hours (consider anti-Xa levels)
  • Wait following block: 6 - 12 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Fondaparinux treatment - NAB timings

A
  • Wait following dose: Avoid (consider anti-Xa levels)
  • Wait following block: 12 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

NSAIDs - NAB timings

A
  • Wait following dose: no additional precautions
  • Wait following block: no additional precautions
36
Q

Aspirin - NAB timings

A
  • Wait following dose: no additional precautions
  • Wait following block: no additional precautions
37
Q

Clopidogrel - NAB timings

A
  • Wait following dose: 7 days
  • Wait following block: 6 hours
38
Q

Prasugrel - NAB timings

A
  • Wait following dose: 7 days
  • Wait following block: 6 hours
39
Q

Ticagrelor - NAB timings

A
  • Wait following dose: 5 days
  • Wait following block: 6 hours
40
Q

Tirofiban - NAB timings

A
  • Wait following dose: 8 hours
  • Wait following block: 6 hours
41
Q

Eptifibatide - NAB timings

A
  • Wait following dose: 8 hours
  • Wait following block: 6 hours
42
Q

Abciximab - NAB timings

A
  • Wait following dose: 48 hours
  • Wait following block: 6 hours
43
Q

Dipyridamole - NAB timings

A
  • Wait following dose: no additional precautions
  • Wait following block: 6 hours
44
Q

Warfarin - NAB timings

A
  • Wait following dose: INR less than 1.5
  • Wait following block: following catheter removal
45
Q

List the drugs that require no additional precautions with respect to neuraxial blockade

A
  • Aspirin
  • NSAIDs
  • Dipyridamole (wait 6 hours post NAB before dosing)
46
Q

What are the safety features of a PCA?

A
  • Anti-syphon valves
  • Anti-reflux valves
  • Kept below level of heart
  • Naloxone prescription
  • Handover to nurses on prescription and who to call for help
  • Regular observations
47
Q

Advantages of PCA

A
  • Flexible to individual requirements
  • Not reliant on nursing time
  • Faster alleviation of pain
  • Patient in control
  • Reduced anxiety
  • Better satisfaction
48
Q

Disadvantages of PCA

A
  • Equipment error
  • Human error
  • Not suitable for some patients (OA)
  • Cost/Maintenance of pumps
  • Regular training of nurses
49
Q

What are some of the NPSA safety recommendations for epidural use?

A
  • Label bags
  • Ready-to-use bags
  • Separate storage for LA agents
  • Yellow colour coding (catheter, bags, pumps)
  • Rationalise dose range
  • Dedicated infusion pump
  • Regular training
  • Audut
  • Guidelines
50
Q

What are the indications for TENS?

A
  • Nociceptive pain
    • Post op
    • Labour
  • Neuropathic pain
    • DM neuropathy
  • Musculoskeletal pain
    • Osteoarthritis
51
Q

What are the contraindications to TENS?

A
  • Pacemaker
  • Epilepsy
  • Communication difficults (doesn’t understand how to use)
52
Q

How does TENS work?

A
  • Not clear
  • Some evidence of gate theory
  • Increased endogenous opiod
  • Decreased descending inhibition
  • Effect abolished by naloxone
53
Q

Trigeminal neuralgia

A

Paroxysmal, unilateral severe pain within the trigeminal sensory distribution. Often described as lancinating, sudden, severe and short lived (2 seconds - 2 minutes)

54
Q

What is the incidence of trigeminal neuralgia?

A
  • 5-10/100,000
  • F > M
55
Q

List the trigeminal divisions, and their exit foramina

A
  1. V1 Ophthalmic - Superior orbial fissure
  2. V2 Maxillary - Foramen rotundum
  3. V3 Mandibular - Foramen ovale

Think SORO

56
Q

What are the main nuclei of the trigeminal nerve?

A
  • Sensory
    • Mesencephalic nucleus (proprioception)
    • Main sensory nucleus (touch)
    • Spinal nucleus (pain/temp)
  • Motor nucleus
57
Q

Where is the trigeminal ganlion located

A

Petrous temporal bone - Meckel’s cave

58
Q

What is the aetiology of trigeminal neuralgia?

A
  • Nerve root compression by blood vessels at/near entry of nerve roots into pons
    • MRI shows blood vessel contact in 90%
    • Patient wake pain free following decompressive surgery
    • Nerve condution is immediately improved following decompression
  • 5% associated with MS
  • 2% posterior fossa tumours
59
Q

Treatment options for trigeminal neuralgia

A
  • Pharmacological
    • Carbamazapine
    • Phenytoin
    • Baclofen
    • Lamotrigine
  • Interventional
    • EtOH/glycerol/balloon microcompression
      • Very high complication rate
      • Sedation
      • Loss of corneal reflex
      • Masseter weakness
      • Dysaesthesia
      • Anaesthesia dolorosa
  • Surgery
    • Microvascular decompression
    • Gamma knife (less successful)
60
Q

What treatment options are availible for neuropathic pain?

A
  • Gabapentin/Amitriptyline/Duloxetine/Pregabalin
    • Think “GADuP” in neuropathic pain
    • Start with gabapentin, then move sequentially though the others.
  • PRN Tramadol “rescue therapy”
  • Capsaicin if localised
  • TENS
  • 5% lidocaine patches
  • Spinal cord stimulation
    • Pain > 6 months, >50/100 VAS
61
Q

What is the cure rate for Trigeminal Neuralgia following MVD?

A

70% at 5 years

62
Q

Pain management of bony metastases

A
  • MDT/palliative care/patient and family centered
  • WHO analgesic ladder - include ketamine and methadone
  • Radiotherapy
  • Bisphosphonates
  • Percutaneous vertebral augmentation
  • Epidural steroids
63
Q

Establishing palliative analgesia for the opiate naive

A
  • Use oromorph for 24 hours
  • Half the dose and give as MST BD
  • Prescribe 1/6th total dose as breakthrough
64
Q

What pain interventions are availible for palliative care?

A
  • Brachial plexus catheters
  • Epidurals/intrathecal catheters
    • Fully external
    • External with subQ port
    • Fully implanted
  • Intrathecal neurolysis
    • Phenol
    • Alcohol
  • Cordotomy (C1/2 spinothalamic - mesothelioma)
65
Q

List some pain assessment tools

A
  • Unidimentional
    • Numerical Rating Scale (NRS)
    • Verbal Rating Scale (VRS)
    • Visual Analogue Scale (VAS)
  • Multidimentional
    • The Brief Pain Inventory
    • The McGill Pain Questionnaire
    • Hospital Anxiety and Depression Score
  • Children
    • COMFORT scale
    • Wong Baker Scale
    • FLACC
  • Patients with communication difficulty
    • MOBID-2
    • Doloplus
    • PainAID
    • Abbey Scale
66
Q

Describe the Brief Pain Inventory

A
  • uses NRS (1-10) in a number of different domains
  • Self administered
  • Chronic pain is qualified by how it has been over the past 24 hours
    • Right now
    • At its best
    • At its worst
    • On average
  • Localisation of pain on a body chart
  • How much pain interfears with 7 aspects ADLs
67
Q

What is this?

A

The Brief Pain Inventory

68
Q

Describe the McGill Pain Questionnaire

A
  • Establishes sensory and affective aspects of pain
  • Strengths
    • Multidimentional
    • Validated
    • Useful for monitoring trends
  • Weaknesses
    • Takes time
    • Relies on patient understanding
69
Q

Describe HADS

A
  • Single questionnaire with
    • 7 questions for anxiety
    • 7 questions for depression
  • Each ranked 0-3
  • Total max score 21
70
Q

List some tools for screening for neuropathic pain

A
  • Self completing
    • LANSS
    • S-LANSS
  • Doctor completing
    • Pain-DETECT
    • DN4
71
Q

What are the red flags for back pain?

A
  • Signs/Symptoms of cauda equina/cord compression
  • Immunosupression
  • Trauma
  • Hx of cancer
  • Nocturnal pain
  • Systemic effects (weight loss, fevers, night sweats)
  • Thoracic pain
  • Abnormal gait
  • Age of onset < 20 years or > 55 years
72
Q

What are the yellow flags for back pain?

A
  • A - Attitudes
  • B - Beliefs
  • C - Compensation
  • D - Diagnosis
  • E - Emotions
  • F - Family
  • W - Work
73
Q

What are the primary chemical stimulants for pain activation?

A
  • H+
  • K+
  • ATP
  • Adenosine
  • NO
  • Histamine
  • Peptides
  • Serotonin
74
Q

How is pain transmitted?

A
  • C fibres (unmyelinated, slow, burning, poorly localised)
  • Ad fibres (myelinated, fast, sharp, well localised)
75
Q

Where do Ad/C fibres synapse?

A

Rexed lamina 1, 2 (and 5) or the dorsal horn

76
Q

What is the gate control theory of pain?

A

Activation of Ab fibres in the dorsal horn leads to activation of inhibitory interneurones inhibiting C fibres

77
Q

What are the risk factors for phantom limb pain?

A
  • Lower limb
  • Previous pain in limb
  • B/L amputation
  • Catastrophising
  • Severe post op pain
78
Q

Treatment options for phantom limb pain

A
  • IV Calcitonin (acute rescue therapy)
  • Ketamine
  • Morphine
  • Gabapentin
  • Amitriptyline
  • Sensory discrimination
  • Mental imagery
  • CBT
  • Surgical revision - if a clear cause
79
Q

Pathophysiology of phantom limb pain

A
  • Peripheral
    • Ectopic discharges from damaged nerves
    • Upregulation of Na channels
    • Sensory-sympathetic coupling (similar to CRPS)
  • Spinal
    • Ab fibre sprouting in DH
    • Sensitisation of the DH, mediated by increased NMDA receptors
  • Central
    • Cortical remapping
80
Q

What are the complications of a coeliac plexus block?

A
  • Severe hypotension
  • Bleeding 2° to aortic/caval injury
  • Intravascular injection
  • Abdominal organ puncture
  • Paraplegia (phenol injection into the arteries that supply the spinal cord)
  • Sexual dysfunction (injected solution spreads to the sympathetic chain bilaterally).
  • Lumbar nerve root irritation (injected solution tracks backwards towards the lumbar plexus).
81
Q

What are the appropraite solutions for injection during a coeliac plexus block?

A
  • Non-malignant pain: 10 ml 0.5% bupivacaine each side
  • Malignant pain: 5 ml 6% aqueous phenol + 5 ml 0.5% bupivacaine each side
  • Always inject region with radio-opaque die first to confirm correct placement
82
Q

What are the indications for a stellate ganglion block?

A
  • Pain syndromes
    • Complex regional pain syndrome type I and II
    • Refractory angina
    • Phantom limb pain
    • Herpes zoster
    • Shoulder/hand syndrome
    • Angina
  • Vascular insufficiency
    • Raynaud’s syndrome
    • Scleroderma
    • Frostbite
    • Obliterative vascular disease
    • Vasospasm
83
Q

What are the contraindications for a stellate ganglion block?

A
  • Coagulopathy
  • Recent myocardial infarction
  • Pathological bradycardia
  • Glaucoma
84
Q

Describe the proceedure for a stellate ganglion block

A
  • SLIMRAG
  • Supine position, neck slightly extended, head turned away, jaw open
  • Instil a bleb of LA for skin
  • Needle puncture located:
    • Between trachea and carotid sheath
    • At the level of the cricoid cartilage (C6)
    • Palpate for Chassaignac’s tubercle (TP of C6)
  • Retract sternocleidomastoid and carotid artery laterally as the index finger palpates Chassaignac’s tubercle
  • Press firmly onto the tubercle to reduce the distance between the skin and bone
  • Direct needle onto the tubercle, then redirected medially and inferiorly toward the body of C6. After the body is contacted, withdraw 1-2 mm
  • Confirmed needle position by fluoroscopy: checking for spread of radiocontrast cephalad/caudad confirmed in both AP and lateral views.
  • Aspirate to rule out intravascular placement
    • Consider small adrenaline test dose as IV injection into the vertebrals can result in significant LA neurotoxicity
  • Cautiously inject 10-15 ml in 3 ml divided doses with intermittent aspiration
  • Place patient in the sitting position to facilitate the spread of anaesthesia inferiorly to the stellate ganglion
  • The onset of Horner’s syndrome indicates a successful block.
85
Q

What does the BPS class as weak opiods?

A
  • Codeine
  • Dextropropoxyphene
  • Dihydrocodeine
  • Meptazinol