Induction Meds: Etomidate Flashcards
(29 cards)
In general, thiobarbiturates are much more _____ soluble and have a greater _______ than oxybarbiturates.
What atom do thiobarbiturates have in lieu of an oxygen in the second position (like oxybarbiturates)?
- Lipid; potency
- Sulfur
What is unique about Etomidate’s organic chemical structure?
It is the only carboxylated imidazole containing compound.
When is etomidate water-soluble vs lipid-soluble?
- H₂O-soluble at acidic pH.
- Lipid-soluble at physiologic pH.
What percentage of etomidate is propylene glycol?
What is the result of this?
- 35% propylene glycol
- resulting in pain on injection and venous irritation.
Which induction agent can be given without an IV?
How is this?
Etomidate - can be given sub-lingual.
Only drug with direct systemic absorption in oral mucosa that bypasses hepatic metabolism
Why does etomidate have a low incidence of myoclonus?
- Trick Question. Etomidate has a high incidence of myoclonus, just like all other induction agents.
What is the onset of Etomidate?
1 minute
What is etomidate’s Vd?
How does clearance compare to thiopental?
What is the result of this clearance?
- Large Vd
- 5x faster clearance than thiopental resulting in a prompt awakening.
What metabolizes Etomidate?
Hydrolysis by hepatic microsomal enzymes and plasma esterases.
What is the induction dosage range for Etomidate?
0.3 mg/kg IV
What is the best use for Etomidate?
- Induction for unstable cardiac patients.
Especially with little or no cardiac reserve
What needs to be used concurrently with etomidate when performing a laryngoscopy/tracheal intubation?
Why?
- use with Opioids
- etomidate has no analgesic effects.
What is Etomidate’s most common side effect?
How often does this occur?
- Involuntary Myoclonic Movements
- that occurs with 50 - 80 % of administrations.
What should be administered with Etomidate to prevent involuntary myoclonic movements?
Fentanyl 1-2 μg/kg IV
Etomidate has a dose dependent inhibition of the conversion of cholesterol to _________________.
What does this mean clinically?
- Cortisol
- Etomidate decreases SNS capability to respond to stress (longer vent times, hypotension, etc.)
How long does adrenocortical suppression with etomidate last?
- 4-8 hours.
Compared to Thiopental, Etomidate will lower plasma concentrations of what substance?
Cortisol
What are etomidate’s effects on CBF & CMRO₂ ?
Why is this and what does it do?
↓CBF & ↓CMRO₂ 35%-45% due to being
a potent direct cerebral vasoconstrictor.
- Will also ↓ICP.
CMRO₂ is couple with both CBF and _______.
CMRG (cerebral metabolic requirement of glucose)
What is the EEG profile of etomidate?
- More excitatory than thiopental
- May activate seizure foci
- Augments SSEP amplitude.
Etomidate results in significant hypotension if _________not treated prior to induction?
- Hypovolemia
esp. high 0.45 mg/kg IV
Histamine release via etomidate is mediated through what?
- Trick question. Etomidate does not release histamine.
What is the pulmonary profile of etomidate?
-
No change in minute ventilation.
d/t increase in respiratory rate compensate decrease in tidal volume - Less respiratory depression than barbiturates
- Rapid IV produces apnea
-Stimulates CO₂ medullary centers
How much of Etomidate is protein bound?
What protein does it bind to?
76% albumin bound
