Factors predisposing to formation and/or rebreathing of Compound A include each of the following EXCEPT:

Factors predisposing to formation and/or rebreathing of Compound A include each of the following EXCEPT:

• A. Low fresh gas flow
• B. Use of soda lime rather than Baralyme
• C. High absorbent temperatures
• D. Fresh absorbent

Answer: (B)

Compound A forms when sevoflurane degrades on CO2 absorbents in the presence of strong bases, especially under conditions that keep the anesthetic in contact with the absorbent longer or at higher temperatures. Baralyme contains powerful base catalysts (such as Ba(OH)2) that promote this degradation, so using Baralyme is more likely to lead to Compound A formation than using soda lime, which is why choosing soda lime instead of Baralyme is the exception in this list. The other factors—low fresh gas flow, which increases contact time between sevoflurane and the absorbent; and higher absorbent temperature, which speeds the chemical reaction—both predispose to more Compound A formation (and potential for rebreathing of anesthetic). Fresh absorbent is also more chemically active and thus can predispose to the reaction, reinforcing why this option fits with the overall pattern.

Compound A forms when sevoflurane degrades on CO2 absorbents in the presence of strong bases, especially under conditions that keep the anesthetic in contact with the absorbent longer or at higher temperatures. Baralyme contains powerful base catalysts (such as Ba(OH)2) that promote this degradation, so using Baralyme is more likely to lead to Compound A formation than using soda lime, which is why choosing soda lime instead of Baralyme is the exception in this list. The other factors—low fresh gas flow, which increases contact time between sevoflurane and the absorbent; and higher absorbent temperature, which speeds the chemical reaction—both predispose to more Compound A formation (and potential for rebreathing of anesthetic). Fresh absorbent is also more chemically active and thus can predispose to the reaction, reinforcing why this option fits with the overall pattern.