CNIM Somatosensory Evoked Potentials (SSEP) 2

Question 1

Which filter settings are typically used for intraoperative SSEP recording?

Accepted Answer

30–3000 Hz bandpass

Answer

1–30 Hz bandpass

Answer

0.1–10 Hz bandpass

Answer

3000–10000 Hz bandpass

Question 2

What is the recommended number of averages to obtain a reliable SSEP waveform in the operating room?

Accepted Answer

200–500

Answer

10–20

Answer

50–100

Answer

1000–2000

Question 3

Bilateral loss of SSEP signals with preserved baseline recordings most likely indicates:

Accepted Answer

A systemic physiological change such as hypotension or hypothermia

Answer

Equipment failure only

Answer

Unilateral cord injury

Answer

Normal response to anesthesia deepening

Question 4

Which anesthetic agent has the least suppressive effect on cortical SSEP amplitudes?

Accepted Answer

Propofol-based total intravenous anesthesia (TIVA)

Answer

Isoflurane at 1.5 MAC

Answer

Halothane at 1 MAC

Answer

Nitrous oxide 70%

Question 5

The stimulation rate for median nerve SSEP should avoid multiples of 60 Hz to prevent:

Accepted Answer

Electrical line noise contamination

Answer

Nerve damage from overstimulation

Answer

Muscle artifact from repetitive stimulation

Answer

Cortical spreading depression

Question 6

During prone positioning for spinal surgery, SSEPs are lost immediately after positioning. The most appropriate first step is to:

Accepted Answer

Check for brachial plexus stretch or peripheral nerve compression at pressure points

Answer

Alert the surgeon of spinal cord injury

Answer

Increase stimulation intensity to maximum

Answer

Discontinue monitoring