Pain Flashcards
A patient who underwent a thoracotomy six months ago reports shooting pain on
the chest wall occurring without any trigger. This is known as:
Post thoracotomy pain syndrome
IASP Post-thoracotomy pain syndrome:
“Pain that recurs or persists along a thoracotomy incision at least two months following the surgical procedure” in general it is burning or stabbing pain with dysesthesia thus shares many features of neuropathic pain.
Dysesthesia: unpleasant abnormal sensation spontaneous or evoked
The analgesic drug with the most favourable Number Needed to Treat (NNT) for neuropathic pain is:
a) Amitriptyline
b) Gabapentin
c) Tramadol
d) Pregabalin
e) Carbamazepine
REPEAT
Tramadol
APMSE 5th edition:
Tramadol is an effective treatment for neuropathic pain with NNT of 4.4 (95%CI 2.9 to 8.8)
Alpha-2-delta ligands (gabapentinoids) are the only anticonvulsants with proven efficacy in the treatment of chronic neuropathic pain.
At doses of 1,800 mg to 3,600 mg/d, gabapentin is effective in treating neuropathic pain, in particular caused by postherpetic neuralgia (NNT 6.7; 95%CI 5.4 to 8.7)
Pregabalin
Postherpetic neuralgia: 300 mg/d pregabalin (NNT 5.3; 95%CI 3.9 to 8.1) (4 RCTs, n=713) and 600 mg/d (NNT 3.9; 95%CI 3.1 to 5.5) (4 RCTs, n=732);
* Painful diabetic neuropathy: 600 mg/d pregabalin (NNT 7.8; 95% CI 5.4 to 14) (5 RCTs, n=1,015);
* Mixed or unclassified post-traumatic neuropathic pain: 600 mg/d pregabalin (NNT 7.2; 95%CI 5.4 to 11) (4 RCTs, n=1,367);
* Central neuropathic pain (mainly SCI): 600 mg/d pregabalin (NNT 9.8; 95%CI 6.0 to 28) (3 RCTs, n=562).
Amitriptyline NNT 4.6 (TCAs are effective in treatment of neuropathic pain (amitrip NNT 4.6))
Amitriptyline
By order of favourable NNT:
- TCAs (amitriptyline) NNT: 3.6, NNH: 9
- Strong opioids NNT 4.3 NNH 11.7
- Tramadol NNT: 4.7, NNH 12.6
- SNRIs (duloxetine and venlafaxine) NNT 6.4, NNH 11.8
- Gabapentin NNT: 7.2 NNH 25.6
- Pregabalin NNT:7.7, NNH 13.9
ANZCA Pain book
Treatment of chronic neuropathic pain after SCI (Guy 2016 GL). These guidelines recommend:
- First line: pregabalin, gabapentin and amitriptyline;
- Second line: tramadol and lamotrigine (in incomplete SCI);
- Third line: Transcranial direct current stimulation (tDCS) alone and combined with visual illusion;
- Fourth line: TENS, oxycodone and dorsal root entry zone lesions.
NP Self-report of pain in children is usually possible by the age of:
a. 2 yo
b. 4 yo
c. 6 yo
d. 8 yo
REPEAT
A) 4
4 yo = wong baker faces score 3-18.
8 yo = Visual analogue scale.
https://www.rch.org.au/rchcpg/hospital_clinical_guideline_index/Pain_assessment_and_measur ement/
APMSE 5 also
A 30-year-old has had a free-flap operation of eight hours duration. They received an intraoperative remifentanil infusion and 10 mg morphine 30 minutes before the end of the operation. During recovery their pain score increased from 6/10 on arrival to 9/10 despite a further 10 mg of intravenous morphine. The most likely diagnosis is:
a. Acute behavioural change
b. OIH
c. Inadequate analgesia
D. Physical dependence
Nikki:
B)
Opioid induced hyperalgesia;
The key features are long case with Remi running, as well as increased pain following additional opioids.
https://associationofanaesthetists-publications.onlinelibrary.wiley.com/doi/full/10.1111/anae.13602
NP The oral morphine equivalent of tapentadol 50 mg (immediate release) is:
a) 5mg
b) 10mg
c) 15mg
d) 20mg
e) 25mg
B) 15mg
50mg x0.3
Tapentadol Conversion at 0.3
Tramadol conversion at 0.2
Oxycodone 1.5
Hydromorphone 5
Buprenorphine patch mcg/hr@2
Fentanyl patch mcg/hr @3
Oral Tapentadol 25mg = 8mg Oral Morphine
Oral Oxycodone 5mg = 8mg Oral Morphine
Oral Tramadol 25mg = Oral Morphine 5mg
Oral Hydromorphone 4mg = Oral Morphine 20mg
S/L Buprenorphine 200mcg = 8mg Oral Morphine
IV Oxycodone 5mg = Oral Morphine 15mg
IV Morphine 5mg = Oral Morphine 15mg
IV Hydromorphone 1mg = Oral Morphine 15mg
21.1 A woman is having a potentially curative primary breast cancer resection. Compared with a sevoflurane and opioid technique, using a regional anaesthesia-analgesia technique with paravertebral block and a propofol infusion will result in
a. Decreased cancer recurrence
b. Decreased chronic pain and recurrence
c. Decreased incision pain at 6 months
d. Decreased CPSP pain at 6 months
e. Decreased CPSP pain at 12 months
Fuck this question
e. Decreased CPSP pain at 12 months
or it could be updated with an option that says makes no difference
most likely they will just remove the question and this is a big waste of time
https://pubs.asahq.org/anesthesiology/article/135/6/1091/117748/Preoperative-Paravertebral-Block-and-Chronic-Pain
—>This says it makes no difference in 2021
https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD007105.pub4/full
—-> this says weak evidence but it helps prevent persistent post surgical pain at 3-12months in 2018
—-> ANZCA pain book references this article
ANZCA pain book
https://www.bjaed.org/article/S2058-5349(18)30101-X/fulltext
A recent review showed that, whilst there was little effect on intra- and postoperative opioid consumption and PONV, patients receiving either both single-shot injections or placement of paravertebral catheters had less acute pain in the first 72 h after surgery.
There is also a suggestion that the use of TPVB for acute postsurgical pain may protect against the development of chronic postsurgical pain after breast surgery at 6 months.
For breast cancer surgery any form of regional anaesthesia (18 RCTs, n=1,297) reduces CPSP 3 to 12 months after surgery compared with systemic analgesia (OR 0.43; 95%CI 0.28 to 0.68) (NNT 7); specifically paravertebral block (PVB) (6 RCTs, n=419) is effective (OR 0.61; 95%CI 0.39 to 0.97) (NNT 11).
In our study population, regional anaesthesia-analgesia (paravertebral block and propofol) did not reduce breast cancer recurrence after potentially curative surgery compared with volatile anaesthesia (sevoflurane) and opioids. The frequency and severity of persistent incisional breast pain was unaffected by anaesthetic technique. Clinicians can use regional or general anaesthesia with respect to breast cancer recurrence and persistent incisional pain.
https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(19)32313-X.
23.1 A patient has an acute attack of shingles (herpes zoster). The development of post-
herpetic neuralgia can best be reduced by the administration of
A. Ibuprofen
B. Gabapentin
C. Aciclovir
D. Amitriptyline
E. Oxycodone
D. Amitriptyline
Amitriptyline (used in low doses for 90 days from onset of the herpes zoster rash) reduces the incidence of postherpetic neuralgia
N.B
Antiviral agents started within 72 hours of onset of the herpes zoster rash accelerate the resolution of acute pain (U) (Level I) but do not reduce the incidence, severity and duration of postherpetic neuralgia
UTD
Both Gabapentinoids and TCAs are effective at TREATING postherpetic neuralgia. The former have lower risk of discontinuation due to adverse side effects.
For moderate or severe pain, use gabapentinoids.
22.2 A 48-year-old man is day two post-laparoscopic high anterior resection. He has used 42 mg of intravenous morphine in the past 24 hours. You wish to start him on oral tapentadol immediate release. The most appropriate equianalgesic dosage would be
a) 50mg six times a day
b) 100mg six times a day
c) 200mg six times a day
d) 300 mg six times a day
a) 50mg six times a day
42mg IV Morphine = 126mg Oral Morphine
126/8= 15.75
15.75 x 25 = 393.75 (*400mg/day Tapentadol)
Option 50mg 6 times a day = 300mg
As direct OME to tapentadol conversion is 400mg, a 300mg dose represents a 25% dose reduction, which is line with a 25-50% dose reduction due to incomplete cross-tolerance during opioid rotation.
Oral Tapentadol 25mg = 8mg Oral Morphine
Oral Oxycodone 5mg = 8mg Oral Morphine
Oral Tramadol 25mg = Oral Morphine 5mg
Oral Hydromorphone 4mg = Oral Morphine 20mg
S/L Buprenorphine 200mcg = 8mg Oral Morphine
IV Oxycodone 5mg = Oral Morphine 15mg
IV Morphine 5mg = Oral Morphine 15mg
IV Hydromorphone 1mg = Oral Morphine 15mg
22.1 Complex regional pain syndrome is NOT characterised by
a. Vasomotor
b. Sudomotor
c. Pain distal to primary injury
d. Hypoaesthesia
e. Edema
Hypoasthesia - Veldman criteria
Pain distal to primary injury – Not mentioned specifically in Budapest criteria, but in Veldman
Hypoaesthesia = reduced sensation to pain
23.1 A risk factor for the development of chronic postsurgical pain is having
a. Age >65
b. Male
c. Pain at site 1 month prior to surgery
d. Higher SES
c. Pain at site 1 month prior to surgery
Pain itself is a risk factor: the strongest predictors of CPSP are chronic preoperative pain and the severity of acute postoperative pain
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5741327/#:~:text=Pain%20its
23.1 Self-report of pain in children is usually possible by the age of
a. 2 yo
b. 4 yo
c. 6 yo
d. 8 yo
b) 4yo
4 yo = wong baker faces score 3-18.
8 yo = Visual analogue scale.
https://www.rch.org.au/rchcpg/hospital_clinical_guideline_index/Pain_assessment_and_measur ement/
APMSE 5 also
23.1 Of the following, the drug that is LEAST likely to provide effective analgesia following paediatric tonsillectomy is
A. Inhalational anesthesia
B. Remifentanil at end of case
C. Dexamethasone
D. Intranasal ketamine
or
a. Ketamine
b. Clonidine
c. NSAIDs
d. Paracetamol
e. Dexamethasone
A. Inhalational anesthesia
or
b. Clonidine
Prospect: two studies focused on tonsillectomy, and those did not show any additional analgesic effect of clonidine when used on top of adequate baseline medication after tonsillectomy.
PROSPECT
https://associationofanaesthetists-publications.onlinelibrary.wiley.com/doi/10.1111/anae.15299#:~:text=The%20basic%20analgesic%20regimen%20should,analgesic%20and%20anti%2Demetic%20effects.
21.2, 22.2 Of the following, the procedure that is most commonly associated with chronic pain after surgery is
a) Amputation
b) Mastectomy
c) Thoracotomy
d) TKR
e) Hernia repair
a) Amputation
Top 10 Rank order:
1. Amputation 30-85%
2. Thoracotomy 5-67%
3. Mastectomy 11-57%
4. Inguinal hernia repair 0-63%
5. Sternotomy 28-56%
6. Cholecystectomy 3-56%
7. Knee arthroplasty 19-43%
8. Breast Augmentation 13-38%
9. Vasectomy 0-37%
10. Radical prostatectomy 35%
23.1 A technique which is NOT effective in providing analgesia for a sternal fracture is a
A. Pecs 1
B. Pecs 2
C. Thoracic transversus plane block
D. Subpectoral fascial plane block
A. Pecs 1
https://www.nysora.com/topics/regional-anesthesia-for-specific-surgical-procedures/thorax/pectoralis-serratus-plane-blocks/
20.1 Which drug not metabolised by CYP2D6?
a) Oxycodone
b) Tramadol
c) Amitryptiline
d) Codeine
e) Hydromorphone
e) Hydromorphone
23.1 A 30-year-old woman has her bipolar disorder well controlled with lithium therapy. The analgesic agent LEAST suitable for her is
a. Tramadol
b. Diclofenac
c. Oxycodone
d. Methadone
b) diclofenac
LIthium perioperative concerns:
- Prolongation of NMB
- Reduction in anaesthetic agent requirement
- Avoid NSAIDs
- No withdrawl symptoms
- Discontinue 24hrs before surgery
NSAIDs differentially alter lithium concentrations by multiple mechanisms, and one of these is to reduce prostaglandin E2
BJA: perioperative advice for psychotropic drugs
21.2 When performing a paediatric pain assessment, the five elements assessed to obtain the FLACC score are
a) face, legs, activity, cry, consolability
b) face, legs, arms, cry, consolability
c) function, legs, arms, cry, crossed legs
d) frown, legs, activity, cry, crossed arms
a) face, legs, activity, cry, consolability
20.2 An analgesic which is a category A drug using the Australian and New Zealand categories for prescribing medicines in pregnancy is
a) Codeine
b) Methadone
c) Tramadol
d) Oxycodone
e) Morphine
Answer: a) Codeine
TGA Pregnancy categories https://www.tga.gov.au/prescribing-medicines-pregnancy-database
Category A
■ Codeine
Category C
■ Methadone
■ Tramadol
■ Oxycodone
■ Morphine
21.1 A patient has bipolar disorder and is on long term lithium therapy. An analgesic which should be avoided is
a. Diclofenac
b. Tramadol
c. Oxycodone
d. Methadone
a. Diclofenac
LIthium perioperative concerns:
- Prolongation of NMB
- Reduction in anaesthetic agent requirement
- Avoid NSAIDs
- No withdrawl symptoms
- Discontinue 24hrs before surgery
NSAIDs differentially alter lithium concentrations by multiple mechanisms, and one of these is to reduce prostaglandin E2
BJA: perioperative advice for psychotropic drugs
