Certified Hemodialysis Technologist/Technician Exam Vascular Access and Cannulation 1 — Questions and Answers
Question 1: What is the preferred vascular access type for chronic hemodialysis patients?
- Tunneled central venous catheter
- Non-tunneled catheter
- Arteriovenous fistula (Correct answer)
- Arteriovenous graft
Correct answer: Arteriovenous fistula
The arteriovenous fistula (AVF) is the gold standard vascular access for hemodialysis due to its superior longevity and lower complication rates.
Question 2: The 'buttonhole' or constant-site cannulation technique involves:
- Using a new site every treatment
- Inserting needles at the same site and angle each treatment (Correct answer)
- Only using the arterial needle
- Rotating between three sites
Correct answer: Inserting needles at the same site and angle each treatment
The buttonhole technique involves cannulating the exact same site at the same angle each treatment, creating a fibrous tract that reduces pain and aneurysm formation.
Question 3: Which sign during fistula assessment indicates possible stenosis or outflow obstruction?
- Soft, easily compressible thrill
- Pulsatile, hard-feeling access with high venous pressures (Correct answer)
- Bruit heard at anastomosis only
- Low arterial pressures during dialysis
Correct answer: Pulsatile, hard-feeling access with high venous pressures
A pulsatile, hard-feeling access with elevated venous pressures during dialysis suggests downstream stenosis impeding blood flow.
Question 4: When cannulating an AVF, the arterial needle should be inserted pointing in which direction relative to blood flow?
- Always antegrade (toward the heart)
- Always retrograde (away from the heart)
- Retrograde or antegrade depending on facility protocol and access characteristics (Correct answer)
- Perpendicular to the vessel
Correct answer: Retrograde or antegrade depending on facility protocol and access characteristics
Arterial needle direction (antegrade or retrograde) depends on facility protocol and individual access characteristics to optimize blood flow.
Question 5: A patient's fistula has a bruit that is continuous and high-pitched throughout systole and diastole. This is:
- Abnormal — indicates steal syndrome
- Normal — indicates good blood flow through the access (Correct answer)
- Abnormal — indicates thrombosis
- Normal only if present at the anastomosis
Correct answer: Normal — indicates good blood flow through the access
A continuous, soft, low-pitched bruit heard throughout the cardiac cycle indicates a well-functioning AVF with adequate blood flow.
Question 6: Which complication of AVF cannulation is characterized by blood tracking into surrounding tissue during needle insertion?
- Thrombosis
- Infiltration/hematoma (Correct answer)
- Stenosis
- Aneurysm
Correct answer: Infiltration/hematoma
Infiltration occurs when the needle is not properly seated in the vessel lumen, allowing blood to extravasate into surrounding tissue and form a hematoma.
Certified Hemodialysis Technologist/Technician Exam Vascular Access and Cannulation 1
What is the preferred vascular access type for chronic hemodialysis patients?