Induction Meds: Propofol Flashcards

1
Q

What is the most common concentration of a 1% solution?

A
  • 10mg/mL

S39

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

What are the inactive ingredients in propofol? Why is one particularly important?

A
  • 1.2% Lecithin (from egg yolks) can cause anaphylaxis with egg allergies.
  • 2.25% glycerol
  • 10% soybean oil

S39

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

What are the disadvantages of propofol’s inactive ingredient composition?

A
  • ↑ bacterial growth
  • ↑ plasma triglycerides with prolonged infusions
  • Pain on injection

S39

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

Differentiate Ampofol and Aquavan.

A

Ampofol:
- low-lipid
- no preservative that burns on injection more often.

Aquavan:
- prodrug with less injection pain but causes dysesthesias. –
- Slower onset
- larger Vd
- high potency.

S40

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

What is the mechanism of action of propofol?

A

GABA-A receptor modulator that increases Cl⁻ conductance.

S41

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

How does propofol cause immobility through spinal cord-depression?

A
  • Trick question. Immobility from propofol is not from drug-induced spinal cord depression.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the clearance characteristics of propofol?

A

The clearance of propofol is primarily through hepatic metabolism
with minor contributions from renal clearance and pulmonary elimination.

S 42

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

What metabolizes propofol?

A

CYP450 and UGT1A9

S42

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

What is the E ½ time of propofol?

A
  • 30 - 90 minutes

S 42

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

What is the context-sensitive half-time of propofol?
Is this low or high?

A
  • 40 minutes (for an 8 hours infusion)
  • Low CS ½ time.

S42

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Differentiate blood pressure and heart rate changes that occur with propofol vs thiopental.

A
  • Propofol: ↓BP & ↓HR
  • Thiopental: ↓BP & ↑HR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Does propofol cross the placenta?
What are the consequences of this?

A
  • Yes but is rapidly cleared from neonatal circulation.

S45

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Do cirrhosis and renal dysfunction have significant effects on propofol metabolism?

A

No

S45

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What drug is the induction drug of choice?

A

Propofol

S46

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is theinduction dose of propofol in adults and children?

A
  • Adults: 1.5-2.5 mg/kg IV
  • Pediatrics:** higher doses** due to larger central volume and clearance rate.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the induction dose of propofol in the elderly?

A

1 mg/kg IV (25 - 50% lower than regular adult)

S47

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What plasma Propofol levels would correlate with unconsciousness?
What about awakening?

A
  • Unconscious: 2 - 6 μg/mL
  • Awake: 1 - 1.5 μg/mL

S47

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

What is the conscious sedation dose of Propofol?

A

25 - 100 μg/kg/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the characteristics of Propofol in the context of conscious sedation?

A
  • Minimal analgesia but has anti-convulsive and amnestic properties.
  • Prompt recovery w/ low residual sedation
  • ↓ risk of PONV
  • Midazolam or opioids as adjuncts.

S47

19
Q

What are the anti-emetic properties of Propofol?
Why is this thought to occur?

A
  • Very anti-emetic (more effective than Ondansetron)
  • Direct depressant of vomiting center

S49

20
Q

What is the sub-hypnotic dosing for propofol?

A

10 - 15 mg IV, followed by 10 mcg/kg/min

S49

21
Q

What is the anti-pruritic dosing of propofol?

A

10 mg IV

from Neuraxial opioids or cholestasis

S50

22
Q

What is the anti-convulsant dosing of Propofol?

A

1 mg/kg IV

S50

23
Q

What are “other” category benefits of propofol?

A
  • Bronchodilation
  • Anti-emetic
  • Anti-pruritic
  • Anti-convulsant
  • Low dose analgesia
  • Antioxidant
  • Does not trigger MH

S50

24
Q

What are Propofol’s effects on CMRO₂, CBF, and ICP?

A
  • ↓ CMRO₂, CBF, and ICP

S51

25
Q

Large doses of Propofol may ___________ cerebral perfusion pressure.

A

decrease

S51

26
Q

Though Propofol will not produce seizures, it will produce __________.

A

myoclonus
(involuntary twitching or jerking)

S51

27
Q

Between thiopental, propofol, and isoflurane, which is the least EEG suppressive?

A

Propofol

S52

28
Q

Which would decrease blood pressure more: thiopental or propofol?

A

Propofol

S53

29
Q

What is the mechanism for propofol-induced hypotension?
What conditions will exaggerate this effect?

A
  • SNS inhibition causing ↓SVR and ↓ ICF Ca⁺⁺
  • exaggerated in Hypovolemia, elderly, and LV compromise

S53

30
Q

How is propofol-induced hypotension from induction usually counteracted?

A
  • Intubation (from laryngeal stimulation).
31
Q

Why is bradycardia seen with propofol?
What would occur with propofol overdose?

A
  • ↓SNS response & baroreceptor reflex
    depression.
  • Profound bradycardia & eventual asystole with overdose

S54

32
Q

What are the pulmonary effects of propofol?
How does this change with opioids?

A
  • Dose-dependent depression of respiratory drive.
  • Synergistic resp depression with opioids
  • Intact hypoxic pulmonary vasoconstriction response
  • Painful surgical stimulation counteracts the ventilatory depressant effects

S55

33
Q

What severe condition(s) can occur with prolonged Propofol infusions?

A

Hepatocellular injury or Propofol Infusion Syndrome.

S56

34
Q

What is Metabolic acidosis thought to occur from poisoning of electron transport chain and impaired oxidation of fatty acids?

A

Propofol Infusion Syndrome

S57

35
Q

What relatively benign condition(s) can occur from prolonged propofol infusions?
Why does this happen?

A

Green and cloudy urine from phenols and uric acid crystals.

Neither alters renal function.

S56

36
Q

What infusion dosing can result in Propofol Infusion Syndrome?

A

> 75 μg/kg/min for longer than 24 hours

S57

37
Q

What is the worst side effect in children who have Propofol Infusion Syndrome?

A
  • Severe, refractory, fatal bradycardia

S57

38
Q

What are the symptoms of Propofol Infusion Syndrome?
How is Propofol Infusion Syndrome diagnosed?

A
  • Urine changes, lactic acidosis, brady-dysrhythmias, and rhabdomyolysis.
  • ABG & serum lactate concentrations

*Reversible in the early stage

S57

39
Q

What are the “other” organ system effects of propofol?

A
  • Injection pain (give lido before)
  • ↓ IOP
  • Plt aggregation inhibition
  • Allergic reactions (lecithin)
  • Prolonged myoclonus
  • Abuse/misuse

S58

40
Q

What is the Induction dose of Propofol

A

1.5 - 2.5 mg/kg IV

S37

41
Q

What is the conscious sedation dose of Propofol?

A

25 - 100 µg/kg/min

S37

42
Q

What is the maintenance dose of Propofol?

A

100 to 300 µg/kg/min

S37

43
Q

What does rapid injection (<15 seconds) of Propofol produce?

A

unconsciousness within 30 seconds

S37

44
Q

What is the clearance of Propofol?

A

30 - 60 mL/kg/min

S42 and S44