Which anesthetic would increase both the amplitude and latency of somatosensory evoked potentials?

Which anesthetic would increase both the amplitude and latency of somatosensory evoked potentials?

• A. Isoflurane
• B. Nitrous oxide
• C. Etomidate
• D. Vecuronium

Answer: (C)

During somatosensory evoked potentials, the anesthetic choice matters because it can either preserve or degrade the sensory signal. Volatile anesthetics and nitrous oxide tend to dampen the SSEPs, reducing amplitude and slowing conduction (increasing latency). Etomidate, however, is relatively preservation-friendly for SSEPs: it provides hypnosis with minimal disruption to ascending sensory pathways and can even enhance the evoked response by reducing background cortical activity and improving the signal-to-noise ratio. This can manifest as a larger amplitude, and there may be a modest increase in latency due to overall CNS depression. A neuromuscular blocker doesn’t affect SSEPs since it acts peripherally on muscles, not the neural conduction measured by SSEPs. So etomidate best fits the scenario of increasing both amplitude and latency of SSEPs.

During somatosensory evoked potentials, the anesthetic choice matters because it can either preserve or degrade the sensory signal. Volatile anesthetics and nitrous oxide tend to dampen the SSEPs, reducing amplitude and slowing conduction (increasing latency). Etomidate, however, is relatively preservation-friendly for SSEPs: it provides hypnosis with minimal disruption to ascending sensory pathways and can even enhance the evoked response by reducing background cortical activity and improving the signal-to-noise ratio. This can manifest as a larger amplitude, and there may be a modest increase in latency due to overall CNS depression. A neuromuscular blocker doesn’t affect SSEPs since it acts peripherally on muscles, not the neural conduction measured by SSEPs. So etomidate best fits the scenario of increasing both amplitude and latency of SSEPs.