Acute Pain & OFA pt3

Question 1

What drug is fentanyl structurally similar to?

Answer 1

Meperidine

Question 2

Fentanyl has ____ potency, ____ onset of action and _____ duration of action.

Answer 2

High potency
Rapid onset
Short duration

Question 3

What is the priniciple metabolite of fentanyl?

Answer 3

Norfentanyl

Detectable in urine up to 72 hours after single dose.

Question 4

Why is elimination of fentanyl slightly prolonged despite very short duration of action?

Answer 4

Lungs serve as large inactive reservoir (up to 75% of initial dose undergoes first pass pulmonary uptake).

Question 5

Why is fentanyl more potent and rapid than morphine?

Answer 5

Greater lipid solubility

Question 6

What is responsible for fentanyl’s short duration of action?

Answer 6

Rapid redistribution to fat and muscle

Question 7

What is the protein binding of fentanyl?

Answer 7

84%

Question 8

What is hydromorphone and how is it formed?

Answer 8

Hydrogenated ketone of morphine formed by N-demethylation of hydrocodone

Question 9

Hydromorphone is ______ times as potent as morphine when administered orally.

Answer 9

3 - 5 times

Question 10

Hydromorphone is ______ times as potent as morphine when administered parenterally.

Answer 10

8.5 times

Question 11

What is hydromorphone’s primary metabolite?

Answer 11

Hydromorphone-3-glucuronide

Question 12

What should be known about Hydromorphone-3-glucuronide?

Answer 12

• Lacks analgesic effects
• May potentiate neurotoxic effects (allodynia, myoclonus, seizures).

Question 13

When is Hydromorphone-3-glucuronide’s neurotoxic side effects a significant concern?

Answer 13

Patients with renal insufficiency

Question 14

What is the typical dose of parenteral Hydromorphone?

Answer 14

0.2 - 2 mg

Question 15

What is the typical oral dose of hydromorphone?

Answer 15

2 - 8 mg

Question 16

What is the duration of action of hydromorphone?

Answer 16

3 - 4 hours

Question 17

What is hydrocodone derived from?

Answer 17

Codeine

Question 18

How does the potency of hydrocodone and codeine compare?

Answer 18

Hydrocodone is 6 - 8 x more potent than codeine

Question 19

What are the two most abused opioids?

Answer 19

1st = Oxycodone
2ⁿᵈ = Hydrocodone

Question 20

What are the two metabolites of hydrocodone metabolism?

Answer 20

• Hydromorphone (via CYP2D6)
• Norhydrocodone (inactive) via CYP3A4

Question 21

What is the morphine equivalent of hydrocodone?

Answer 21

1 mg morphine = 3 mg hydrocodone

Question 22

What is typical hydrocodone dosing?

Answer 22

2.5 - 10mg w/ 300 - 750mg acetaminophen q4-6hours
consider max dose of acetaminophen

Question 23

What receptors does buprenorphine have affinity to? (3)

Answer 23

μ - partial agonist (strong)
κ - antagonist (strong)
δ - agonist (weak)

Question 24

What benefits does buprenorphine provide? (4)

Answer 24

• ↓ respiratory depression
• ↓ immune suppression
• ↓ constipation
• No accumulation in renal patients

Question 25

What is the primary metabolite of buprenorphine?

Answer 25

Norbuprenorphine by CYPs

Question 26

What should be known about norbuprenorphine?

Answer 26

- 1/50th analgesic activity of buprenorphine - ↑↑↑ Respiratory depression

Question 27

What is the IV/IM buprenorphine dose equivalence for morphine?

Answer 27

0.3mg IM buprenorphine = 10mg morphine

Question 28

What is the half life of buprenorphine?

Answer 28

Long 20 - 73 hours

Question 29

Should buprenorphine be avoided in patients with renal impairment?

Answer 29

No. Hepatic elimination primarily

Question 30

What are the side effects and drug interactions of buprenorphine?

Answer 30

Question 31

What opioid receptors do NSAIDs bind to?

Answer 31

Trick question. NSAIDs inhibition COX as their method of pain modulation.

Question 32

What is the recommended dose for celecoxib?

Answer 32

100mg daily

Question 33

What is the recommended dose for diclofenac?

Answer 33

50 mg BID

Question 34

How might antidepressants work as pain medication adjuvants?

Answer 34

Modulation of spinal cord transmission to reduce pain signaling

Question 35

Whats the IV dose of fentanyl for pain?

Answer 35

20 - 50 mcg

Question 36

What anticonvulsants are used as adjuvant medication to relieve pain? (4)

Answer 36

* Gabapentin (watch for sedation/ respiratory depression in older patients) * Phenytoin (dilantin) * Carbamazepine (tegretol) * Topiramate (topamax)

Question 37

What skeletal muscle relaxants are used as adjuvant medication to relieve pain? (5)

Answer 37

* Baclofen (Lioresal®) * Carisoprodol (Soma®) * Cyclobenzaprine (Flexeril®) * Methocarbamol (Robaxin®) * Tizanidine (Zanaflex®)

Question 38

What is Opioid Free Anesthesia?

Answer 38

* Technique where no intra-operative systemic, neuraxial, or intracavitary opioid is administered during the anesthetic.

Question 39

Opioids acting on the Mu receptor will produce these unwanted effects. (5)

Answer 39

* Respiratory depression * Decrease GI motility/ constipation * Urinary retention * Prurititis * Physical dependence

Question 40

Opioids acting on the Kappa receptor will produce these unwanted effects.

Answer 40

* Respiratory depression * Dysphoria

Question 41

Opioids acting on the Delta receptor will produce these unwanted effects. (4)

Answer 41

* Respiratory depression * Urinary retention * Prurititis * Physical dependence

Question 42

What is opioid-induced hyperalgesia (OIH)?

Answer 42

* State of nociceptive sensitization caused by exposure to opioids. * The condition is characterized by a paradoxical response whereby a patient receiving opioids for the treatment of pain might actually become more sensitive to certain painful stimuli.

Question 43

What are the recommended starting doses for tylenol and ibuprofen? Max doses?

Answer 43

* Tylenol: 500-1000 mg q6h Max 4g/day * Ibuprofen: 200mg TID Max 3200mg/day

Question 44

In general, the PO dose of opioids is about ___ the IV/IM dose.

Answer 44

PO dose is ~3x the IV/IM dose