CHBT Vascular Access and Cannulation Basics

Question 1

Which type of vascular access is considered the 'gold standard' for long-term hemodialysis due to its superior patency and lower infection risk?

Accepted Answer

Arteriovenous fistula (AVF)

Answer

Arteriovenous graft (AVG)

Answer

Tunneled central venous catheter (CVC)

Answer

Non-tunneled temporary catheter

Question 2

What is the 'rope ladder' cannulation technique?

Accepted Answer

Rotating needle insertion sites along the entire length of the access, distributing puncture trauma evenly

Answer

Inserting two needles at the same site every session to maximize flow

Answer

Using a guidewire to thread the needle into the access vessel

Answer

Placing needles perpendicular to the vessel wall to reduce aneurysm risk

Question 3

Before cannulating an arteriovenous fistula, which assessment is essential?

Accepted Answer

Auscultating for a bruit and palpating for a thrill to confirm access patency

Answer

Taking the patient's blood pressure in the fistula arm

Answer

Applying a tourniquet above the fistula for 5 minutes

Answer

Comparing the fistula arm temperature to the opposite arm

Question 4

What is the minimum maturation time typically required for an AVF before it can be used for hemodialysis?

Accepted Answer

At least 4–6 weeks (ideally 3–4 months)

Answer

7–10 days post-creation

Answer

Immediately after surgical creation

Answer

6–12 months without exception

Question 5

What is 'infiltration' in the context of vascular access cannulation?

Accepted Answer

Leakage of blood into surrounding tissue when a needle punctures through or outside the vessel wall

Answer

Introduction of air into the blood circuit through a loose needle connection

Answer

Backflow of dialyzed blood into the arterial needle

Answer

Contamination of the access site with skin bacteria during insertion

Question 6

Why should blood pressure never be measured in the arm containing an arteriovenous fistula?

Accepted Answer

Cuff compression can restrict fistula blood flow and potentially cause thrombosis

Answer

The bruit creates noise that interferes with Korotkoff sounds, giving inaccurate readings

Answer

The fistula creates artificially elevated pressures due to high flow

Answer

Blood pressure measurement is prohibited in any arm with a chronic wound