How does unstable blood pressure during SSEP monitoring in the OR affect cortical EPs?

When considering how unstable blood pressure affects somatosensory evoked potentials (SSEPs) during monitoring, it's important to understand that fluctuations in blood pressure directly influence the amplitude of the responses recorded.

SSEPs are sensitive to changes in cerebral blood flow, which can be altered by variations in blood pressure. When blood pressure is unstable, the ability of the brain to receive a consistent blood supply can be compromised, leading to variability in the amplitude of the recorded potentials. A decrease in blood flow can reduce synaptic transmission efficiency and ultimately lead to a lower amplitude of the evoked responses, which is why fluctuating amplitudes would be expected.

In contrast, while latency changes can occur with extreme fluctuations in physiological conditions, they are less directly influenced by transient changes in blood pressure compared to amplitude stability. The latency refers to the time it takes for the signal to travel from the periphery to the cortex, which may be relatively stable unless there are more significant systemic or neurological impacts at play.

Maintaining body temperature is also crucial, as hypothermia can exacerbate the instability in neurophysiological responses, but provided that the temperature is kept above critical levels, the minimal changes would not negate the influence of blood pressure on amplitude. Hence, fluctuations