EMG Risk Management & Mitigation 3 — Questions and Answers
Question 1: When performing EMG on a patient with known HIV/AIDS, which precaution is MOST important?
- Wearing double gloves and using standard precautions with single-use needles (Correct answer)
- Refusing to perform the procedure
- Using only surface electrodes
- Administering prophylactic antibiotics beforehand
Correct answer: Wearing double gloves and using standard precautions with single-use needles
Standard (universal) precautions with single-use disposable needles and appropriate PPE protect both the technician and patient regardless of HIV status.
Question 2: A patient develops a rapidly expanding hematoma at an EMG needle site in the antecubital fossa. What is the priority action?
- Continue the study and document the hematoma
- Apply direct pressure, hold the study, and assess neurovascular status (Correct answer)
- Apply ice only and continue with other muscles
- Aspirate the hematoma with a syringe
Correct answer: Apply direct pressure, hold the study, and assess neurovascular status
Expanding hematomas in the antecubital fossa can compress the median nerve or brachial artery; direct pressure and neurovascular assessment are immediate priorities.
Question 3: Which of the following represents a failure of the 'timeout' or pre-procedure verification process in EMG?
- Confirming the patient's name and date of birth
- Proceeding with the study before verifying the clinical indication (Correct answer)
- Checking the referral for laterality before starting
- Asking the patient about medication allergies
Correct answer: Proceeding with the study before verifying the clinical indication
Performing the study without verifying the clinical indication risks performing an unnecessary or inappropriate procedure and constitutes a failure of the pre-procedure safety check.
Question 4: During electrical stimulation for nerve conduction studies, what patient safety risk is specifically associated with stimulating over broken or macerated skin?
- Increased risk of electrical burns and pain due to reduced skin resistance (Correct answer)
- Decreased nerve conduction velocity
- Increased risk of vasovagal syncope
- Interference with cardiac monitoring
Correct answer: Increased risk of electrical burns and pain due to reduced skin resistance
Broken skin dramatically lowers electrical resistance, concentrating current density and increasing the risk of electrical burns and disproportionate pain.
Question 5: A patient scheduled for lumbar paraspinal EMG discloses they had posterior lumbar spinal fusion surgery 3 weeks ago. What is the most appropriate response?
- Proceed but use shorter needle depth
- Postpone paraspinal needle examination until surgical healing is adequate, typically 3–6 months (Correct answer)
- Use surface electrodes over the paraspinal region instead
- Proceed only if the surgeon gives verbal consent
Correct answer: Postpone paraspinal needle examination until surgical healing is adequate, typically 3–6 months
Needle insertion into recently operated paraspinal tissue risks infection, wound disruption, and hemorrhage; postponing until adequate healing is the safest approach.
Question 6: What is the rationale for grounding the patient during nerve conduction studies?
- To increase stimulator output efficiency
- To reduce electrical shock risk and minimize stimulus artifact in recordings (Correct answer)
- To improve patient comfort by dissipating heat
- To calibrate the nerve conduction velocity calculation
Correct answer: To reduce electrical shock risk and minimize stimulus artifact in recordings
A ground electrode placed between the stimulator and recording electrodes dissipates stray electrical fields, reducing the large stimulus artifact that can obscure early waveform components.
Question 7: Which of the following is a recognized risk of performing repetitive nerve stimulation (RNS) in a patient with severe carpal tunnel syndrome?
- Transient worsening of median nerve entrapment symptoms (Correct answer)
- Permanent nerve damage from repeated stimulation
- Risk of inducing myasthenic crisis
- Cardiac arrhythmia from proximal stimulation sites
Correct answer: Transient worsening of median nerve entrapment symptoms
Repetitive stimulation can transiently aggravate symptoms in an already compromised median nerve, so patients should be warned of potential temporary symptom exacerbation.
EMG Risk Management & Mitigation 3
When performing EMG on a patient with known HIV/AIDS, which precaution is MOST important?