Sevoflurane Flashcards
What is another name for sevoflurane?
Ultane
When was sevo synthesized and by whom?
late 1960s/early 1970s by Richard Wallin at Travenol Laboratory (Baxter)
When was it approved for use in US?
1995, was delayed and reconsidered in 1980s with increased outpatient surgery.
What are some characteristics of sevoflurane?
clear, colorless, sweet smelling (kind of), highly fluorinated, stable at room temp, no additives or stabilizers
What is the MW of Sevo?
200.05g
What is the boiling point of sevo?
58.6C
What is the vapor pressure of sevo?
157 mmHg
How many F ions are in Sevoflurane?
7…sevo=seven
What gases are methyl ethyl ethers?
des and iso
What gas is a methyl isopropyl ether?
sevo
What is the MAC of sevo?
2.0 (1.7-2.2)
What is the blood:gas of sevo?
0.63, low
What is the oil:gas of sevo?
53.4
How is sevo stored?
amber bottles
What is formed when degradation occurs with CO2 absorbents?
Compound A (pentafluoroisopropenyl fluoromethyl ether) Theoretically can cause nephrotoxicity but no reports in humans
How does Compound A occur?
When sevo interacts with sodalime or baralyme, a degradation product (not metabolite) forms. Increased formation with low fresh gas flows and high temperatures.
How can you prevent Compound A from occuring?
make sure sodalime doesn’t dry out, maintain temperature, use higher fresh gas flows
What does the packaging label say to do to avoid exposure to compound A?
sevo should not exceed 2 MAC hours at flow rates of 1-2L/min, fresh gas flow rates <1 are not recommended. We just keep flow rates at 2L/min or higher if long case.
True/False: Sevo reacts with desiccated dioxide absorbents and flammable compounds can be produced.
True, at high temps spontaneous combustion can occur.
Can you do inhalation induction with sevo?
yes, 4-8% sevo in 50% mixture of N2O and oxygen takes 1-3 min for induction.
True/False: Emergence is slow with sevo.
False: quick emergence mostly eliminated through lungs, sometimes too quick causing emergence delirium.
Who does emergence delirium most impact?
children 1-5 incidence 12-13%, but can be all ages, successfully treated with 1-2 mcg/kg of fentanyl. May be blunted by switching gases for maintenance or pre-treatment with benzos.
How is sevo metabolized?
95% by lungs, other 5% in the liver to form hexafluoroisopropanol (HFIP) and inorganic Fluoride. HFIP is conjugated with gluconronic acid and excreted in the urine.
What effects does sevo have on the cardiovascular system?
mild decrease in contractility, less decrease in SVR and ABP compared to others, no coronary steal, not associated with tachycardia at <2 MAC, CO not as well maintained as with other gases, no arrhythmias. (some peds get brady but not 1st consideration)
