Prop, Etomidate, Ketamine Flashcards

1
Q

Is Propofol soluble or insoluble in the blood?

A

Insoluble

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

What do we add to propofol? What is the concern with one of the components?

A

10% soybean oil

  1. 25% glycerol
  2. 2% egg lecithin

Egg lecithin is related to allergy

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

Is propofol chiral?

A

No

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

What is propofol’s pain on injection related to?

A

the phenol group

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

Name two ways you can prevent pain on injection with Propofol.

A

Large bore IV in AC

administer with lidocaine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the antagonist to propofol?

A

there isn’t one! the only way for it to stop working is for it to wear off

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

What is the most important advantage to propofol?

A

rapid return to consciousness with minimal residual effects

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

What is the difference between Diprivan and Propofol?

A

Diprivan is made in the U.S. and doesn’t have sulfites. pH 7-8.5. Contains 0.05% EDTA
Propofol is made in other countries and has sulfites. pH 4.5-6.4. Contains 0.025% sodium metabisulfite or benzyl alcohol

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

If you have an asthmatic patient and have to use this drug, which suspension should you use - Diprivan or Propofol?

A

Diprivan. No sulfites which are detrimental to asthmatics

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

Is propofol an acid or a base? What is the pKa?

A

Acid. pKa 11

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What receptor does propofol act on?

A

GABA - A

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

Is propofol an antagonist?

A

No!

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

You are doing a spinal case and the surgeon tells you he needs to assess spinal motor neurons throughout the procedure. Would propofol be an appropriate agent?

A

Yes - spinal motor neuron excitability not altered (benefit over gases that have 3 A’s)

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

Which other neurotransmitter is affected by propofol to a lesser extent?

A

Glycine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Does propofol undergo first pass?

A

Yes - tissue uptake in the lungs

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

How is propofol metabolized?

A

Extensive hepatic metabolism by CYP450

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

Phase I or Phase II metabolism of Prop?

A

Phase II glucuronidation

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

What is the effect time of propofol?

A

4-6 minutes - redistribution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the half-life of propofol?

A

11 hours (r/t active metabolite)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is propofol’s active metabolite?

A

4-hydroxypropofol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Context sensitive half time?

A

less than 40 minutes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Is propofol appropriate for a patient with hepatic or renal dysfunction?

A

Yes! Not influenced by hepatic or renal dysfunction, can be given with cirrhosis/ESRD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is a consideration with propofol for patients over 60 years old?

A

decreased rate of plasma clearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does propofol bind reversibly with? To what extent?

A

erythrocytes and plasma proteins (50%)
plasma albumin (48%)
free (2%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

On the plasma concentration curve, would the effect time of propofol be related to the alpha or beta phase?

A

Alpha - propofol’s effect time is related to re-distribution in single bolus dose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

You have propofol circulating in the plasma, is it producing an effect?

A

Maybe, maybe not. Know that just because it’s in the plasma, it may be bound to proteins and cannot exert an effect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Increased free fraction of propofol would be associated with which patients?

A

Patients with severe hepatic/renal disease
pregnancy
elderly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

If your hepatic blood flow is terrible, how will that effect the metabolism of propofol?

A

It won’t! Clearance exceeds hepatic blood flow. Enzymes will cause glucuronidation regardless of hepatic blood flow to metabolize

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is an ideal property of propofol?

A

Rapid and pleasant loss and return to consciousness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

You gave propofol and your patient starts twitching. Is it likely a seizure?

A

No. Propofol may induce myoclonus secondary to disinhibition of subcortical centers (but less so than etomidate)
more so in younger patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Is propofol a good drug for neuro patients?

A

Yes - neuroprotectant effects*

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the CV effects of propofol?

A

decrease in sympathetic tone and vasodilation
cardiac and baroreceptor depression
significant effect on SVR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Will propofol cause respiratory depression?

A

YES. If you give it in sufficient doses, almost everyone will stop breathing**

r/t decreased sensitivity of respiratory center to CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Your patient is having a bronchospasm. Which drug may be useful?

A

propofol! it causes minimal bronchodilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Induction dose of prop? Which patients should you adjust this for?

A

1.5-2.5 mg/kg IV
decrease in elderly
increase in pediatrics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

You have an elderly patient coming in for a total knee arthroplasty. The case takes 1-3 hours. You don’t want to expose them to gas and opioids for that long. What would be a better technique?

A

Regional for analgesia and areflexia, propofol for amnesia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

You have a patient coming in for an endoscopy. What would be an appropriate drug and IV sedation dose?

A

Propofol - prompt recovery without residual sedation

25-100 mcg/kg/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Which of the 3 A’s does propofol cause?

A

Amnesia only

no analgesic properties**

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Can propofol be used with an anxiolytic or opioid?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Your patient tells you they had severe post op N&V after their last surgery. Is prop appropriate?

A

Yes - anti-nausea properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Maintenance of anesthesia dose for prop? what should it be used with?

A

100-300 mcg/kg/min

short-acting opioid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Antiemetic dose of prop?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Antipruritic dose of prop?

A

10mg IV

44
Q

Anticonvulsant dose of prop?

A

1 mg/kg IV

45
Q

What type of pain can propofol be effective for?

A

Minimal to no analgesic effects, but may be beneficial with neuropathic pain

46
Q

Lecithin allergy is associated with what drug? what foods can it be found in?

A

Propofol. Eggs**, peanuts, soybean

47
Q

What are risk factors for PRIS?

A

> 4mg/kg/hr (66mcg/kg/min) for greater than 48h, critical illness, high fat low carb intake, concomitant catecholamine infusion, steroid administration, inborn errors of mitochondrial fatty acid oxidation

48
Q

Your patient goes into DKA or rhabdo. What is happening?

A

PRIS

49
Q

Your patient has a high anion gap metabolic acidosis. What is happening?

A

PRIS

50
Q

Signs of PRIS?

A

High anion gap metabolic acidosis (DKA, rhabdo), cardiac failure, persistent brady refractory to treatment, fever, severe hepatic and renal disturbances

51
Q

CV Clinical features of PRIS

A

hypotension, bradycardia, ischemic EKG, V tach, V fib, arrhythmias, wide QRS, asystole, HF

52
Q

Respiratory features of PRIS

A

hypoxia, pulmonary edema

53
Q

Renal features of PRIS

A

AKI, hyperkalemia

54
Q

Musculoskeletal features of PRIS

A

Rhabdo

55
Q

Metabolic features of PRIS

A

hyperthermia, high AG metabolic acidosis, urine discoloration

56
Q

Hepatic features of PRIS

A

Hepatomegaly, abnormal LFTs, steatosis, lipidemia, hypertriglyceridemia

57
Q

Is propofol addictive?

A

Yes - wellbeing on emergence and tolerance buildup

58
Q

When might etomidate be considered for induction for your patient over propofol?

A

Cardiac patient - stable BP and HR with etomidate

59
Q

Is etomidate lipophilic or water soluble?

A

water soluble in acidic pH, lipophilic at physiologic pH. pH 8.1, pKa 4.2 , base.

60
Q

Which is chiral, propofol or etomidate?

A

etomidate

61
Q

Which receptors does etomidate work on?

A

GABA-A

62
Q

Which drug (etomidate or propofol) has more free drug? What does this affect?

A

Etomidate (25%) vs. 2%. More free drug = more risk for adverse effects

63
Q

What process is responsible for metabolism of etomidate?

A

Hydrolysis. plasma esterases and microsomal enzymes in the liver

64
Q

Name 3 drugs that cause myoclonus.

A

Etomidate, Methohexital, Clonazepam.

65
Q

How long is return to consciousness with etomidate?

A

5-15 minutes

66
Q

What are the neurologic effects of etomidate?

A

Decrease in CMRO2 and CBF. Decrease in ICP while maintaining CPP. Some cerebral protection

67
Q

If you administer etomidate or propofol, with which drug would you expect to see less spontaneous breathing?

A

Propofol

greater % of patients will breathe with induction doses of etomidate

68
Q

You give an induction dose of 0.45 mg/kg of etomidate for a cardiac patient. Is this appropriate?

A

No. Doses > 0.45 mg/kg result in decreased BP and CO. Appropriate induction dose 0.2-0.4mg/kg IV

69
Q

Is etomidate a good choice to treat pain?

A

No. No analgesia

70
Q

Does etomidate cause pain on injection?

A

Yes. Burns. Minimal.

71
Q

What is a side effect of etomidate that is unique to this drug?

A

Adrenocortical suppression, more commonly in critically ill, septic patients

72
Q

What is the enzyme that converts cholesterol to cortisol? Which drug inhibits this?

A

11B hydroxylase enzyme

Etomidate

73
Q

what is the allergic incidence with etomidate?

A

low!

74
Q

Which drug is characterized by the patient’s eyes remaining open and a slow nystagmus gaze

A

Ketamine “dissociative anesthesia”

75
Q

Which of the 3 A’s does ketamine produce?

A

Amnesia and Analgesia

76
Q

Rank the 3 drugs from most to least bound to plasma proteins.

A

propofol (98%), etomidate (75%), ketamine (12%)

77
Q

Rank propofol, etomidate, and ketamine from highest to lowest lipid solubility.

A

Highest is propofol, then etomidate, then ketamine

78
Q

How is ketamine metabolized?

A

demethyjation by CYP450 micro enzymes

79
Q

How is ketamine metabolized?

A

demethyation by CYP450 micro enzymes

80
Q

Does ketamine cause respiratory depression?

A

No

81
Q

What lipid vehicle is ketamine mixed with for injection?

A

No lipid vehicle for dissolution. No pain on injection

82
Q

Which drug has metabolism that is dependent on hepatic blood flow? Which has metabolism that exceeds hepatic blood flow?

A

dependent - ketamine

exceeds - prop

83
Q

Onset and half life of ketamine?

A

Onset 15-30 minutes

elimination half life 2-3 h

84
Q

Which other receptors can ketamine act on?

A

muscarinic, monoaminergic, opioid, nicotinic acetylcholine, voltage sensitive sodium, L-type calcium, some GABA

85
Q

How does ketamine exert its analgesic effects?

A

Direct inhibition of cytokines

86
Q

Which drug has an increased risk for laryngospasm/bronchospasm? Which drug is a used to treat this?

A

Ketamine (increased salivary secretions). Propofol.

87
Q

Which drug would be inappropriate for a neuro patient, a patient having cataract surgery, or a patient with CAD?

A

Ketamine

  • Increased CBF, CMRO2, ICP
  • Increased intraocular pressure
  • Increased BP and HR
88
Q

What do you have to give ketamine with? What is the best agent?

A

A benzo - hallucinations otherwise.

Midazolam

89
Q

Which drug is best for trauma or hypovolemic patients?

A

Ketamine

90
Q

What are the IV, IM, and oral doses for ketamine?

A

1-2.5mg/kg
4-8mg/kg IM
10 mg/kg PO

91
Q

True or False: the best time to give Ketamine is 10 minutes prior to surgery. Why or why not?

A

False. Less of an effect than if given at start of surgery when pain starts and receptors are more reactive

92
Q

What is the dose of Ketamine for analgesic effects?

A

0.2-0.5mg/kg

93
Q

Is Ketamine more effective on somatic or visceral pain?

A

Somatic

94
Q

Is Ketamine appropriate in an OB case?

A

Yes. OB anesthesia without neonatal depression, compromised uterine tone, BF, or neonatal status

95
Q

Is Ketamine better for acute or chronic pain?

A

Chronic

96
Q

What is the indication for the ketamine dart?

A

good for pediatric patients with asthma

97
Q

What would be the benefit of giving sub anesthetic doses of ketamine with propofol?

A

Ketamine gives you the analgesic properties and combined with prop it stabilizes hemodynamics and avoids unwanted emergence reactions

98
Q

What can you give to patients who are at risk for increased ICP prior to giving ketamine?

A

Thiopental, Benzo

99
Q

What is the effect if you administer ketamine with succ?

A

Apnea prolonged after administration of succ due to inhibition of plasma cholinesterase

100
Q

What is Ketamine’s effect with NMBDs?

A

Enhancement of their effects

101
Q

How long after administration of Ketamine can emergence delirium occur?

A

24 hours

102
Q

Risk factors for emergence delirium with Ketamine?

A

Age > 15, female, history of personality problems, frequent dreams

103
Q

What is the effect if you give atropine with ketamine?

A

Increased risk of emergence delirium

104
Q

Propofol Half time (h), Vd (L/kg), Cl (mL/kg/min)

A

0.5-1.5h
2.5-3.5 L/kg
30-60 mL/kg/min

105
Q

Etomidate half time (h), Vd (L/kg), Cl (mL/kg/min)

A

2-5 h
2.2-4.5L/kg
10-20 mL/kg/min