Opioids

Question 1

synthetic opioids

Answer 1

Moriphan- agonist/antagonist types (levorphenol, butorphenol)

Diphenyls- methadone

benzomorphans- (for vasodilation) - phenazocine, pentazocine

phenylpiperidines!!!!
- miperidine, fent, alfent, sufent, remifent

Question 2

natural/ semisynthetics

Answer 2

• morphine is natural

- heorin, hydromorphone, codeine semisynth.

Question 3

opioid 4 classifications

Answer 3

• agonist
• partial agaonist
• mixed agonist/ antagonist

Question 4

mu 1

Answer 4

SUPRASPINAL, spinal analgesia
euphoria
low abuse potential
miosis
bradycardia
hypothermia
urinary retention

Question 5

mu 2

Answer 5

crappy side effects.

spinal analgesia
depression of ventilation
physical dependence
marked constipation

Question 6

kappa

Answer 6

supraspinal, spinal analgesia
dysphoria
sedation
low abuse potential
miosis
DIURESIS

***only dynorphins are agonists

Question 7

delta

Answer 7

supraspina, spinal analgesia
depression of ventilation
physical dependence
minimal consitpation
urinary retention

***only enkephalins work here

Question 8

opioids MOA

Answer 8

GPCR
pre and post synaptic

1- increase K conductance
2- inactivate Ca++ Ch

• decreases NT release

Question 9

activation of receptors

Answer 9

1- directly decrease neurotransmission

2- inhibits release of excitatory neurotransmitters (substance P)

Question 10

supraspinal analgesia

Answer 10

receptor activation in periaqueductal/ periventricular gray matter in brain

Question 11

Spinal analgesia

Answer 11

receptor activation in cord and dorsal root ganglion, substantia gelatinosa (inhibit substance P)

Question 12

opioid effects on skeletal muscle

Answer 12

rigidity.

• constrition of laryngeal/pharyngeal muscles
• decreased chest wall compliance (diff or impossible to bag)

inhibition of GABA, increase in Dopa.

Question 13

lipid solubility and neuraxial effects

Answer 13

• penetration into CSF depends on LS
• highly LS will be limited in cephalad migration by uptake into the spinal cord (fentanyl)
• less LS will remain in CSF for transfer to cephalic region (morphine)
• more LS = faster vascular absorption from epidural space…. quicjer peak concentrations of opioid in the blood.

Question 14

side effects of neuraxial opioids

Answer 14

pruritis is most common
n/v
ventilatory depression (rapid with lipophilic, delayed with less lipophilic 6-12 hrs—cant go home.)

Question 15

morphine produces….

Answer 15

analgesia, euphoria, sedation, nausea, pruritis, dry mouth, HISTAMINE, ventilatory depression

bradycardia, SA node inhibition

Question 16

meperidine (demerol) produces…

Answer 16

• sodium channel inhibiton (like LAs)
• ALPHA 2 agonist effects

euphoria, sedation, analgesia

Question 17

morphine peak effects IM/IV, DOA

Answer 17

IM 45 min
IV 15-30 min

DOA 4 hrs

Question 18

meperidine DOA

Answer 18

2-4 hrs

Question 19

hydromorphone

Answer 19

5x more potent than morphine (derivative)
rapid elimination/redistribution
Q4 dosing needed!!!

Question 20

Fentanyl plasma concentration

Answer 20

• does not decrease rapidly and is prolonged by second peak effects.
  (immobilization of sequestered drug from inactive tissue sites)
• accumulation
• especially affected by multiple doses or infusion*
• large Vd

Question 21

Fentanyl uses

Answer 21

• analgesic adjunct
• adjuvant to blunt stimulation of incision, DL
• as sole anesthetic in large doses d/t hemodynamic stability

Question 22

Sufentanil uses

Answer 22

adjunct for surgery and induction

infusion for outpatient surgery

Question 23

Sufentanil compared to fent/morphine

Answer 23

quicker induction
earlier emergence
earlier extubation

Question 24

Alfentanil uses

Answer 24

• useful for blunting hemodynamic response (esp increased HR) to noxious stimuli
• rapid effect
• infusion for outpatient surgery (quick off)

Question 25

remifentanyl unique characteristics

Answer 25

- ester linkage - metabolism by tissue/plasma esterases (not pseudocholinesterases) - minimal accumulation in tissues, even with infusion

Question 26

remifentanyl uses

Answer 26

blunt noxious stimuli | infusion for intermediate- long surgeries where rapid recovery is desired---- neurosurgical, O/P

Question 27

agonist/antagonist qualities

Answer 27

- mu antagonist/partial agonist - kappa partial agonist yield= analgesia with limited ventilatory depression and low probability of dependence - side effects similar to opioids (HD stable, skeletal muscle, urinary urgency, constipation, pruritis, N/V) - dysphoria at Kappa

Question 28

Nalbuphine (Nubain)

Answer 28

- same analgesia as morphine, antagonizes respiratory effects - no CV effects - agonist at Kappa - reverses spasm of sphincter of oddi (intraop use)

Question 29

Butorphenol (Stadol)

Answer 29

- agonist at kappa - weak antagonist/partial agonist at Mu - 5x more potant than morphine analgesia - nasal spray for migraines

Question 30

Naloxone

Answer 30

- pure opioid antagonist - blocks sites, revereses respiratory depression, analgesia - COMPETITIVE at mu, kappa, delta - shorter DOA - titratable - onset 1-2 mins - dose-dependent reversal

Question 31

Naloxone Side Effects

Answer 31

- tachycardia - HTN - Vent Dysrhythmias - severe pain - pulmonary edema!!!! --- underlying CV disease or in healthy patients d/t catecholamine release.

Question 32

meperidine dose

Answer 32

50-100 mg IV this drug is not always effective in patients with severe pain

Question 33

fent dose

Answer 33

1-3 mcg/kg 0.01 to 0.05 mcg/kg/min

Question 34

remifentanil dose

Answer 34

1-2 mcg/kg 0.05- 0.25 mcg/kg/min

Question 35

alfentanil dose

Answer 35

10-20 mcg/kg 0.25- 0.75 mcg/kg/min

Question 36

sufentanil dose

Answer 36

0.1-0.3 mcg/kg .0015- 0.01 mcg/kg/min