Pain Medicine

Question 1

Where do A-beta, C, and A-delta fibers terminate?

Answer 1

A-beta: spinal cord dorsal horn laminae III-V;
C-fibers: I and II;
A-delta: I, III-V

Question 2

A-beta, A-delta, and C fibers velocity?

Answer 2

30-60 m/s;
10-15 m/s;
Less than 1.5 m/s

Question 3

Where are the wide dynamic range neurons located and where do they receive input from?

Answer 3

In laminae III-V;

low threshold A-beta, nociceptive A-delta, and C fibers

Question 4

What is pKa?

Answer 4

pH at which 50% of drug is ionized

Question 5

Metabolites of oxycodone? Key metabolite of hydrocodone? Metabolites of codeine?

Answer 5

Oxymorphone and hydrocodone;
Hydromorphone;
Hydrocodone and morphine

Question 6

Key mixed opioid agonist-antagonist?

Answer 6

Buprenorphine

Question 7

SE’s of opioids?

Answer 7

Respiratory sedation, cough suppression, constipation, sexual dysfunction

Question 8

Most COX-2 selective medications among NSAIDs?

Answer 8

Mobic, celebrex

Question 9

Name a few drug classes you shouldn’t give SSRI/SNRI’s with

Answer 9

TCA’s, MAOI’s, tramadol, some anti-emetics

Question 10

What channel does gabapentin act on?

Answer 10

Alpha-2-delta subunit of L-type CALCIUM channels

Question 11

Idea behind neurovascular theory for migraines?

Answer 11

Release of peptide neurotransmitters (Substance P, neurokinin A, calcitonin gene-related peptide) that vasodilate blood vessels causing extravasation of plasma which stimulates trigem nerve endings

Question 12

Most common headache type?

Answer 12

Tension-type headaches

Question 13

Nerve responsible for post-mastectomy pain?

Answer 13

Intercostobrachial neuralgia (T1-T2)

Question 14

Lung cancer can cause what issue with tubular bones?

Answer 14

Hypertrophic pulmonary osteoarthropathy; get clubbing and periosteal proliferation of the tubular bones, leading to painful arthropathy in ankles, knees, wrists, elbows (KAWE)

Question 15

Some high-yield neuroablative techniques for cancer pain?

Answer 15

Dorsal root entry zone (DREZ) lesioning: selectively destroys neurons located in posterolateral spinal cord;
Cordotomy: selectively ablates spinothalamic tract; good for cancer pain refractory to level 3 treatment on WHO ladder

Question 16

What is pathology of interstitial cystitis? First line treatment?

Answer 16

Chronic inflamm conditions of bladder’s submucosal and muscular layers;
patient education, diet modification, stress management

Question 17

What does the medial branch innervate?

Answer 17

Facet joint, multifidus muscle, interspinal ligament and muscle, and periosteum of neural arch

Question 18

What are intervertebral discs innervated by?

Answer 18

Posteriorly by sinuvertebral nerves, laterally by ventral rami, anterolaterally by gray rami communicans

Question 19

Modic classifications of subchondral marrow for MRI:

Answer 19

1. Bright on T2, dark on T1 (edema)
2. Bright on T2 and T1 (fat)
3. Dark on T2 and T1 (bony sclerosis)

Bright, dark
B, B
D, D

Question 20

Of the local anesthetics, list them by longest duration of action: bupivicaine, lidocaine, ropivacaine, procaine

Answer 20

Bupivicaine equal to ropivacaine more than lidocaine more than procaine

Question 21

What are the particulate steroids vs the non-particulate steroid?

Answer 21

Particulate: betamethasone, methyprednisolone, triamcinolone;
Non-particulate: dexamethasone

Question 22

For neurolysis, which of alcohol and phenol is hypo/hyperbaric relative to CSF?

Answer 22

Alcohol: hypobaric;
phenol: hyperbaric

“E” in phenol and hyperbaric

Question 23

Local anesthetic toxicity symps?

Answer 23

Early: Peri-oral and tongue paresthesias; dizziness, orthostasis;
Late: Muscle twitch, drowsiness, CNS depression, resp depression, tonic-clonic seizures, bradycardia, hypotension, cardiac arrhythmia, cards arrest

Question 24

Borders of the safe triangle are

Answer 24

1. Superior border: horizontal line parallel to inferior border of pedicle
2. Lateral border: lateral edge of vertebral body
3. Hypotenuse: Spinal nerve root

Question 25

Injection target area for stellate ganglion blocks? Classic complication?

Answer 25

Chassaignac tubercle (carotid tubercle) of C6 vertebral body;
Horner's syndrome

Question 26

Why perform a celiac plexus block?

Answer 26

Controlling pain from epigastric viscera, particularly upper abdo neoplasms like pancreatic cancer

Question 27

Complications of implanted drug delivery device?

Answer 27

Infection, skin erosion from hardware, pump failure, catheter kinking, migration, obstruction; and catheter tip granuloma formation