Ch2 Physical Properties of Inhaled Anesthetics Flashcards
What is the primary difference between Isoflurane and Desflurane?
Desflurane has fluorine substituted for chlorine in Isoflurane
This substitution alters their physical properties.
How does the substitution of fluorine affect the vapor pressure of inhaled anesthetics?
It increases the vapor pressure
Higher vapor pressure means easier evaporation.
What effect does fluorine substitution have on the boiling point of inhaled anesthetics?
It decreases the boiling point
This allows for lower temperatures during administration.
What is the impact of fluorine substitution on the biodegradability of anesthetics?
It makes them less biodegradable
This increases their stability.
Which inhaled anesthetic is more stable, Isoflurane or Desflurane?
Desflurane
The fluorine-carbon bond is more stable than the chlorine-carbon bond.
What are the primary degradation products of modern inhaled anesthetics?
Carbon monoxide and compound A
These products can pose health risks.
What role do monovalent bases like sodium hydroxide and potassium hydroxide play in anesthetic degradation?
They cause significant degradation of anesthetics
Their elimination can reduce degradation.
What is the recommended moisture level in soda lime to prevent degradation of inhaled anesthetics?
15% moisture by weight
Moisture protects against degradation.
What is compound A, and why is it a concern?
A degradation product of certain anesthetics that can cause renal injury
It binds irreversibly to proteins in the body.
What are the potential effects of nitrous oxide on human health?
It may affect vitamin B12 metabolism and cause neurologic deficits
Occupational exposure is a significant concern.
True or False: High gas flows help prevent the formation of compound A.
True
High gas flows reduce the concentration of the anesthetic in the absorbent.
Fill in the blank: The _______ of modern inhaled anesthetics is enhanced by fluorine substitution.
stability
What is the importance of monitoring absorbent dryness in inhaled anesthetics?
To prevent degradation and ensure patient safety
Dry absorbent can lead to harmful byproducts.
What is the effect of the presence of aluminum in Isoflurane bottles?
It can lead to spontaneous degradation
This is exacerbated by exposure to light.
What changes in solubility occur with the addition of fluorine to inhaled anesthetics?
Solubility decreases
This is a key reason for the substitution.
What are the challenges associated with the widespread adoption of new absorbents like Amzar?
High cost and reduced absorbent capacity
These factors hinder their use in practice.
What is the typical temperature range in an operating room for anesthetic degradation studies?
20 to 22 degrees Celsius
This range reflects standard conditions during surgeries.
What evidence indicates that compound A causes renal injury in animals?
In rats, evidence includes proteinuria, enzymuria, and renal tubular damage, such as necrosis.
What markers of renal injury are observed in humans exposed to compound A?
In humans, markers include proteinuria, glucose, and urea, but not necrosis.
What does the package label for anesthetic use with compound A indicate?
Use one liter flows for up to two MAC hours, and do not use single fluorine at flow rates less than one liter per minute.
What is the concern with low flow rates in anesthetic delivery?
Low flow rates can lead to the buildup of compound A and increased temperature in the absorbent.
What happens to compound A production at high gas flows?
High gas flows decrease the amount of carbon dioxide reaching the absorbent, reducing compound A production.
What is the minimum flow rate required to avoid risks associated with compound A?
The minimum flow rate is one liter per minute.
How can the absorbent be monitored for dryness?
Check the canister regularly; there are currently no indicators for dryness.
