Which one of the following inhalational anesthetics is most likely to cause fluoride ion nephrotoxicity
**Core Concept**
Inhalational anesthetics can cause various adverse effects, including nephrotoxicity, through different mechanisms. Fluoride ion nephrotoxicity is a specific concern with certain anesthetics that produce fluoride ions as a byproduct of metabolism.
**Why the Correct Answer is Right**
Sevoflurane is an inhalational anesthetic that undergoes cyclization to form A-23187, which is then metabolized to fluoride ions. These fluoride ions can accumulate in the kidneys and cause nephrotoxicity, especially in patients with pre-existing renal impairment. Sevoflurane's metabolism to fluoride ions is facilitated by the enzyme cytochrome P450 2E1.
**Why Each Wrong Option is Incorrect**
**Option A:** Isoflurane is another commonly used inhalational anesthetic, but it does not undergo significant metabolism to fluoride ions. Instead, it is primarily exhaled unchanged.
**Option B:** Desflurane is a newer inhalational anesthetic that is less likely to cause fluoride ion nephrotoxicity due to its low metabolism rate and minimal production of fluoride ions.
**Option C:** Halothane is an older inhalational anesthetic that can cause hepatotoxicity due to its metabolism to trifluoroacetic acid, but it is not associated with fluoride ion nephrotoxicity.
**Clinical Pearl / High-Yield Fact**
When using sevoflurane, especially in patients with pre-existing renal impairment, it's essential to monitor renal function closely and consider using alternative anesthetics to minimize the risk of fluoride ion nephrotoxicity.
**Correct Answer: C. Sevoflurane is most likely to cause fluoride ion nephrotoxicity due to its metabolism to fluoride ions.**