EDT Patient Preparation & Safety 2

Question 1

When applying surface electrodes for an EMG study, which skin preparation step is most critical for obtaining low-impedance recordings?

Accepted Answer

Lightly abrading the skin with fine sandpaper or abrasive pad

Answer

Light skin abrasion removes the high-resistance dead-cell layer of the stratum corneum, reducing inter-electrode impedance to acceptable levels (below 5 kΩ).

Question 2

A patient with a pacemaker is referred for nerve conduction studies. What is the primary safety concern?

Accepted Answer

Electrical stimulation current may inhibit or reset the pacemaker

Answer

External electrical stimulation can be sensed by a pacemaker's sensing circuit and may trigger inappropriate inhibition or mode-switching, posing a cardiac risk.

Question 3

Which grounding principle is essential during nerve conduction studies to minimize electrical shock hazard to the patient?

Accepted Answer

The ground electrode should be placed between the stimulating and recording electrodes

Answer

Placing the ground electrode between the stimulator and recording electrodes reduces stimulus artifact and provides a common reference, improving both safety and signal quality.

Question 4

Before performing electrodiagnostic studies on a patient taking anticoagulant therapy (e.g., warfarin), what specific precaution applies to needle EMG?

Accepted Answer

Superficial muscles should be prioritized; deep muscles carry higher bleeding risk

Answer

In anticoagulated patients, needle EMG can still be performed, but examination of deep or paraspinal muscles with abundant blood supply increases hematoma risk and should be approached cautiously.

Question 5

A patient reports a latex allergy before the start of an electrodiagnostic study. What is the most appropriate immediate action?

Accepted Answer

Verify that all supplies (gloves, electrode adhesives) are latex-free before proceeding

Answer

Latex can be present in gloves and some electrode adhesives; confirming all materials are latex-free is mandatory to prevent anaphylaxis.

(EDT) Electrodiagnostic Technician Certification Practice Test

(EDT) Electrodiagnostic Technician Certification Practice Test

EDT Patient Preparation & Safety 2