UTC Safety & Infection Control 3 — Questions and Answers
Question 1: Which type of hepatitis virus is most efficiently transmitted through needlestick injuries in healthcare settings?
- Hepatitis A
- Hepatitis B (Correct answer)
- Hepatitis C
- Hepatitis E
Correct answer: Hepatitis B
Hepatitis B virus (HBV) is the most efficiently transmitted bloodborne pathogen via needlestick, with a transmission risk of 6–30% per exposure from an HBsAg-positive source.
Question 2: What is the primary purpose of using a transducer sheath/probe cover during endocavitary ultrasound examinations?
- To improve acoustic coupling between probe and tissue
- To protect the patient from electrical hazards
- To provide a barrier against cross-contamination between patients (Correct answer)
- To maintain probe temperature during extended procedures
Correct answer: To provide a barrier against cross-contamination between patients
Probe covers serve as a physical barrier to prevent cross-contamination between patients, though they do not eliminate the need for high-level disinfection after use.
Question 3: Which disinfectant is most appropriate for cleaning ultrasound transducer surfaces between patients in a low-risk (non-invasive) exam setting?
- High-concentration bleach solution
- Low-level disinfectant such as quaternary ammonium compound (Correct answer)
- Glutaraldehyde immersion
- Hydrogen peroxide plasma sterilization
Correct answer: Low-level disinfectant such as quaternary ammonium compound
Non-critical items like transducer surfaces used on intact skin require only low-level disinfection between patients using agents such as quaternary ammonium compounds.
Question 4: A patient has confirmed active pulmonary tuberculosis. Which precaution level is required during bedside ultrasound?
- Standard Precautions only
- Contact Precautions
- Droplet Precautions
- Airborne Precautions (Correct answer)
Correct answer: Airborne Precautions
Active pulmonary tuberculosis is transmitted via airborne particles, requiring Airborne Precautions including an N95 respirator and a negative-pressure isolation room.
Question 5: What is the correct order of steps for donning PPE before entering an isolation room?
- Gloves, gown, mask, eye protection
- Gown, mask/respirator, eye protection, gloves (Correct answer)
- Mask, gloves, gown, eye protection
- Eye protection, gloves, gown, mask
Correct answer: Gown, mask/respirator, eye protection, gloves
The CDC-recommended donning order is gown first, then mask or respirator, then eye protection, and finally gloves to ensure each layer is properly placed and protected.
Question 6: What is the recommended action for a sonographer who is pregnant and is assigned to care for a patient with a cytomegalovirus (CMV) infection?
- Refuse all assignments involving CMV-positive patients
- Follow Standard Precautions diligently; no additional restrictions are required (Correct answer)
- Use Airborne Precautions in addition to Standard Precautions
- Request immediate reassignment from all patient care duties
Correct answer: Follow Standard Precautions diligently; no additional restrictions are required
Standard Precautions are sufficient for CMV, as the virus is not transmitted via casual contact; consistent hand hygiene and PPE provide adequate protection for pregnant healthcare workers.
Question 7: In the context of ultrasound safety, which biological effect is associated with high-intensity focused ultrasound (HIFU) and represents a thermal hazard?
- Cavitation causing cell membrane disruption
- Tissue heating leading to protein denaturation (Correct answer)
- Acoustic streaming altering fluid flow
- Radiation force causing cell displacement
Correct answer: Tissue heating leading to protein denaturation
HIFU delivers concentrated ultrasound energy that generates intense local heating, causing protein denaturation and tissue destruction at the focal point.
UTC Safety & Infection Control 3
Which type of hepatitis virus is most efficiently transmitted through needlestick injuries in healthcare settings?