CRNI Central Venous Access Devices Practice Test 2 — Questions and Answers
Question 1: What is the recommended flushing protocol for an implanted venous access port that is not actively being used?
- Daily flushing with normal saline
- Monthly flushing with heparinized saline (Correct answer)
- Weekly flushing with normal saline
- No flushing is needed when not in use
Correct answer: Monthly flushing with heparinized saline
Implanted ports require monthly flushing with heparinized saline (typically 5 mL of 100 units/mL heparin) when not actively in use to maintain patency. The heparin lock prevents fibrin buildup and clot formation within the port reservoir and catheter lumen. Some newer ports may have different maintenance protocols per manufacturer guidelines.
Question 2: Which assessment finding during a central venous catheter dressing change would indicate possible catheter migration?
- Slight redness at the exit site
- The external catheter length has changed from the documented insertion measurement (Correct answer)
- Small amount of dried blood on the old dressing
- Patient reports mild discomfort during dressing removal
Correct answer: The external catheter length has changed from the documented insertion measurement
A change in the external catheter length from the documented measurement at insertion is the primary indicator of catheter migration. If more catheter is visible externally, the tip may have withdrawn to a suboptimal position. If less is visible, the catheter may have advanced deeper. Either situation requires radiographic confirmation of tip position.
Question 3: A nurse is unable to aspirate blood from a central venous catheter. What should be attempted first?
- Forcefully flush with a 3 mL syringe
- Reposition the patient — turn head, raise arm, have patient cough or perform Valsalva maneuver (Correct answer)
- Instill alteplase immediately
- Remove and replace the catheter
Correct answer: Reposition the patient — turn head, raise arm, have patient cough or perform Valsalva maneuver
Patient repositioning maneuvers should be attempted first when unable to aspirate blood from a CVC. The catheter tip may be resting against the vessel wall, and repositioning can shift it. Turning the head to the opposite side, raising the arm on the catheter side, deep breathing, coughing, or Valsalva maneuver may restore blood return without additional interventions.
Question 4: What is the primary purpose of using an antimicrobial-impregnated central venous catheter?
- To extend the catheter's mechanical lifespan
- To reduce catheter-related bloodstream infection through sustained antimicrobial activity (Correct answer)
- To improve flow rates
- To reduce thrombosis risk
Correct answer: To reduce catheter-related bloodstream infection through sustained antimicrobial activity
Antimicrobial-impregnated catheters (coated with chlorhexidine/silver sulfadiazine or minocycline/rifampin) reduce CRBSI by preventing bacterial colonization on the catheter surfaces. They are recommended for patients expected to have CVCs for more than 5 days in facilities with high CRBSI rates despite adherence to other prevention bundles.
Question 5: Which central venous catheter insertion site has the lowest risk of catheter-related bloodstream infection?
- Femoral vein
- Internal jugular vein
- Subclavian vein (Correct answer)
- All sites have equal infection risk
Correct answer: Subclavian vein
The subclavian vein site has the lowest risk of catheter-related bloodstream infection in adult patients. The femoral site has the highest risk due to proximity to the groin and higher bacterial colonization. The internal jugular has an intermediate risk. Current guidelines recommend the subclavian site when feasible, balanced against the risk of pneumothorax.
Question 6: A patient develops sudden dyspnea, tachycardia, and hypotension during central line removal. What is the most likely complication?
- Vasovagal response
- Venous air embolism (Correct answer)
- Pneumothorax
- Cardiac tamponade
Correct answer: Venous air embolism
Venous air embolism is the most likely complication during central line removal, presenting with sudden dyspnea, tachycardia, and hypotension. Air enters through the tissue tract. Prevention includes positioning the patient in Trendelenburg, having the patient perform Valsalva during removal, and applying an occlusive dressing immediately after catheter withdrawal.
CRNI Central Venous Access Devices Practice Test 2
What is the recommended flushing protocol for an implanted venous access port that is not actively being used?