Induction Agents Flashcards
What organs utilize the most blood supply?
What organs utilize the least?
What organs are in between these two groups?
- Vessel-rich group = 75% CP (brain, heart, liver, kidneys)
- Skeletal muscles & skin = 18% CO
- Fat = 5% CO
- Bone, tendons, & cartilage = 2% CO
What reflexes are we suppressing during stage 1 anesthesia?
If stage 1 anesthesia is maintained, what is it called?
- Coughing, swallowing, and gagging reflexes (lower airway reflexes)
- Conscious sedation
During induction, when would one most likely see laryngospasm?
- Stage 2
During emergence, when would one most likely need to be re-intubated?
- Stage 2
What are the oxybarbituates?
Methohexital
Phemobarbital
Pentobarbital
What are the thiobarbituates?
Thiopental
Thiamylal
Induction dose (IV and per rectum) for Mathohexital (Brevital)?
1.5mg/kg IV
20 - 30 mg/kg rectally
Induction dose for Thiopental?
4mg/kg IV
If a continuous infusion of Brevital is given there can be post-op ____ in 1 out of 3 patients
Seizures
For Propofol, what are the doses for:
1. Induction
2. Maintenance
3. Conscious sedation
4. Sub-hypnotic dose
- Induction = 1.5 - 2.5 mg/kg IV
- Maintenance = 100 - 300 μg/kg/min
- Conscious sedation = 25 - 100 μg/kg/min
- Sub-hypnotic = 10-15 mg IV followed by 10mcg/kg/min
If using propofol as an anti-pruritic, what dose would you give? What about an anti-convulsant?
Anti-pruritic - 10 mg IV
Anti-convulsant - 1 mg/kg IV
Et1/2 of Propofol?
0.5 - 1.5 hrs
What are the inactive ingredients in propofol? Why is one particularly important?
- 1.2% Lecithin (from egg yolks) can cause anaphylaxis with egg allergies.
- 2.25% glycerol
- 10% soybean oil
What are the disadvantages of propofol’s inactive ingredient composition?
- ↑ bacterial growth
- ↑ plasma triglycerides with prolonged infusions
- Pain on injection
What is the mechanism of action of propofol?
- GABA receptor modulator that increases Cl⁻ conductance.
How does propofol cause immobility through spinal cord-depression?
- Trick question. Immobility from propofol is not from drug-induced spinal cord depression.
What are the clearance characteristics of propofol?
The clearance of propofol is primarily through hepatic metabolism, with minor contributions from renal clearance and pulmonary elimination.
What metabolizes propofol?
- CYP450 and UGT1A9
What drug is the induction drug of choice?
Propofol
What are propofol’s effects on CMRO₂, CBF, and ICP?
- ↓ CMRO₂, CBF, and ICP
Large doses of propofol may ____ cerebral perfusion pressure.
decrease
Though propofol will not produce seizures, it will produce ____.
myoclonus