Induction Agent: Propofol

Question 1

What is the generic name of the drug commonly known as Diprivan?

A) Midazolam
B) Fentanyl
C) Propofol
D) Ketamine

Answer 1

C) Propofol

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Question 2

Which of the following are NOT uses of Propofol?

A) IV induction of anesthesia
B) Maintenance of anesthesia with TIVA
C) Long-term sedation in elderly patients
D) Management of PONV

Answer 2

C) Long-term sedation in elderly patients

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Question 3

What is the standard concentration of Propofol used for anesthesia?

A) 1 mg/cc
B) 5 mg/cc
C) 10 mg/cc
D) 20 mg/cc

Answer 3

C) 10 mg/cc

(20cc vial standard). 1% lipid solution

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Question 4

The typical induction dose of Propofol for an adult is:

A) 0.5 mg/kg IV
B) 1 mg/kg IV
C) 2 mg/kg IV
D) 3 mg/kg IV

Answer 4

C) 2 mg/kg IV

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Question 5

For sedation, the dose range of Propofol is:

A) 25–100 mcg/kg/min
B) 50–200 mcg/kg/min
C) 100–300 mcg/kg/min
D) 10–50 mcg/kg/min

Answer 5

A) 25–100 mcg/kg/min

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Question 6

What is the typical dose range of Propofol for Total Intravenous Anesthesia (TIVA)?
A) 10–50 mcg/kg/min
B) 25–75 mcg/kg/min
C) 100–300 mcg/kg/min
D) 400–600 mcg/kg/min

Answer 6

C) 100–300 mcg/kg/min

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Question 7

True or False

Propofol is a controlled substance

Answer 7

False

Question 8

A pretreatment with __________ can help reduce pain on injection with Propofol.

A) 1–2% Lidocaine
B) 0.5% Bupivacaine
C) Fentanyl
D) Midazolam

Answer 8

A) 1–2% Lidocaine

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Question 9

Which of the following statements are true about Propofol’s pharmacokinetics?
Select 3

A) It has a high protein-binding capacity
B) It always requires dose adjustments in patients with renal or liver disease.
C) It is highly accumulative with short-term use.
D) The patient is unconscious within 30 seconds of administration.
E) Propofol is a titratable drug
F) Increased dose for elderly patients

Answer 9

A) It has a high protein-binding capacity (98%)
D) The patient is unconscious within 30 seconds of administration.
E) Propofol is a very titratable drug

Doses rarely need to be changed with renal or liver disease.

Accumulates with long therapy.

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Question 10

The context-sensitive half-time of Propofol is __________, does accumulate with long therapy.

A) >20 minutes
B) >30 minutes
C) >40 minutes
D) >60 minutes

Answer 10

C) >40 minutes

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Question 11

Propofol’s elimination half-life ranges between:

A) 0.5 to 1.5 hours
B) 2 to 4 hours
C) 5 to 7 hours
D) 8 to 12 hours

Answer 11

A) 0.5 to 1.5 hours

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Question 12

Which of the following is an additional benefit of Propofol aside from its sedative properties?

A) Bronchodilation
B) Vasoconstriction
C) Muscle relaxation
D) Anticoagulant effects

Answer 12

A) Bronchodilation

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Question 13

Propofol is considered the best drug to blunt the laryngeal response during which procedure?

A) Endoscopy
B) Bronchoscopy
C) Laryngoscopy
D) Colonoscopy

Answer 13

C) Laryngoscopy

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Question 14

In low doses, Propofol can be used as a rescue medication to treat __________.

A) Hypertension
B) Bradycardia
C) PONV
D) Hypotension

Answer 14

C) PONV Postoperative nausea and vomiting

more effective than zofran

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Question 15

Propofol Infusion Syndrome

Rare problems with Propofol are normally caused by:
Select 3
A) High-dose Propofol infusion (≥ 5 mg/kg/hr)
B) Short-term use in minor surgeries
C) Use in critically ill patients with head injuries
D) Low-dose Propofol infusion ( < 5 mg/kg/hr)
E) Extended infusion duration (> 58 hours)

Answer 15

A) High-dose Propofol infusion (≥ 5 mg/kg/hr)
C) Use in critically ill patients with head injuries
E) Extended infusion duration (> 58 hours)

Critically ill adults with head injuries receiving long term (> 58 hours) and high dose infusions (5 mg/kg/hr)

reversible in early stages, if cardiogenic shock then ECMO

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Question 16

Propofol Infusion Syndrome

Which of the following conditions are associated with long-term, high-dose Propofol infusion?
Select 2
A) Lipidemia
B) Hypercalcemia
C) Hypotriglyceridemia
D) Fatty infiltrates of the liver
E) Low lactate levels

Answer 16

A) Lipidemia
D) Fatty infiltrates of the liver

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Question 17

Propofol Infusion Syndrome

Which of the following is a metabolic disturbance associated long term, high dose propofol infusion?

A) Respiratory alkalosis
B) Metabolic acidosis
C) Respiratory acidosis
D) Metabolic alkalosis

Answer 17

B) Metabolic acidosis

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Question 18

Propofol Infusion Syndrome

Signs or symptoms of receiving long term, high dose infusions of propofol tend to develop:
Select 3

A) Myoglobinuria
B) Hypoglycemia
C) Enlarged liver
D) Rhabdomyolysis.
E) Metabolic alkalosis

Answer 18

A) Myoglobinuria
C) Enlarged liver
D) Rhabdomyolysis.

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Question 19

True or False

Propofol Infusion Syndrome can lead to sudden onset of bradycardia that progresses to asystole and is resistant to treatment.

Answer 19

True

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Question 20

What effect does propofol have on CMRO2, CBF and ICP?

Answer 20

Decrease
Autoregulatory r/t CBF and PaCO2 maintained
Normally the brain keeps cerebral blood flow (CBF) fairly constant even when MAP changes, through vessel constriction/dilation.

ketamine and volatiles increase ICP

Question 21

First pass?

Answer 21

Pulmonary

Question 22

Can propofol cause myoclonus?

Answer 22

Yes

Question 23

Is prop synergistic with opoids?

Answer 23

Yes (increased respiratory depression)

Question 24

Propofol ___ platelet aggregation and ___ IOP

Answer 24

Inhibits, decreases

Question 25

How does propofol affect EEG?

Answer 25

The least

Question 26

How does propofol work (clinical answer)?

Answer 26

Enhances GABAa receptor activity, hyperpolarizes neurons and causes dose dependent CNS depression with hypotension from decreased SVR.

Question 27

T/F immobility from propofol anesthesia is not caused by drug-induced spinal cord depression

Answer 27

TRUE *Propofol does NOT produce immobility by depressing the spinal cord. Immobility (no movement during surgery) mainly comes from the spinal cord --but propofol does not act strongly there. How does propofol produce immobility then? 1. Profound hypnosis (LOC) 2. Strong anmesia and reduced awareness 3. Reduced descending motor output from the brain (but even if propofol suppresses descending motor output, a strong surgical stimulus can still activate spinal reflexes, leading to movement) *volatile anesthetics (Iso, Sevo, Des) Dose-dependent suppression of spinal reflexes MAC 50% = immobilization in 50% of patients Main site: ventral horn / interneurons in spinal cord Mechanism: ↓ excitatory neurotransmission, ↑ inhibitory signaling Volatiles = primary drugs for surgical immobility at the spinal cord level. Other drugs (propofol, opioids, dexmedetomidine): can suppress reflexes somewhat, but never as reliably or as dose-dependently as volatiles.*

Question 28

Dose adjustment for PEDS?

Answer 28

Require higher doses (larger central distribution volume and clearance rate)

Question 29

How does prop cause vasodilation?

Answer 29

Mechanisms include: Direct relaxation of vascular smooth muscle via: Activation of K+ channels → hyperpolarization of smooth muscle → decreased calcium influx → relaxation. Inhibition of calcium release inside smooth muscle → less contraction.

Question 30

How does prop cause bradycardia?

Answer 30

Decreased SNS response and decreased baroreceptor reflexes (aortic arch and carotid sinus)

Question 31

Does a painful surgical stimulation counteract the ventilatory depressant effects of propofol?

Answer 31

Yes

Question 32

If giving prop to PEDS what to give before HR decreases?

Answer 32

Glycopyrolate

Question 33

Decrease in BP for propofol becomes exaggerated in

Answer 33

Hypovolemia, elderly, LV compromise

Question 34

Which medications blunt the hypercarbic response?

Answer 34

Volatiles (except nitrous) Opioids