Why should IONM continue despite electrical cautery obliterating EP waveforms?

The rationale behind continuing intraoperative neurophysiological monitoring (IONM) despite electrical cautery obliterating evoked potential (EP) waveforms stems from the value of monitoring raw, unaveraged data. When cautery is applied during surgery, it can introduce significant electrical noise and disrupt the clarity of the averaged waveforms typically used for monitoring. However, the raw data remains unaffected by averaging processes and retains crucial information that may still be useful for assessing patient neural function.

Monitoring the raw unaveraged data can help clinicians detect changes or potential neural compromise in real-time, even when the cautery is in use. This aspect is particularly important as it allows the IONM team to maintain awareness of the patient's neurological status, which is essential for immediate intervention if necessary. By observing the raw data, even transient, small signals related to neural activity can potentially be identified, which would otherwise be masked in the averaged output.

This understanding highlights the importance of raw data in maintaining effective IONM practices during surgical procedures that involve electrical cautery.