VABC Maintenance & Troubleshooting of Vascular Access Devices 5 — Questions and Answers
Question 1: A pediatric oncology patient's implanted port is accessed for chemotherapy but there is no blood return despite easy flush. Which action is CONTRAINDICATED?
- Repositioning the patient and asking them to cough
- Performing a fluoroscopic dye study to assess tip position
- Forcefully flushing with a 10 mL syringe at high pressure to clear the occlusion (Correct answer)
- Instilling alteplase and allowing a 30-minute dwell
Correct answer: Forcefully flushing with a 10 mL syringe at high pressure to clear the occlusion
Forceful flushing against resistance is contraindicated as it can rupture the catheter, dislodge a thrombus as an embolus, or cause catheter fracture.
Question 2: When accessing an implanted port, the non-coring (Huber) needle should be inserted at which angle?
- 45 degrees to the skin surface
- 90 degrees perpendicular to the port septum (Correct answer)
- 30 degrees bevel up
- 60 degrees toward the port reservoir
Correct answer: 90 degrees perpendicular to the port septum
The Huber needle must be inserted at a 90-degree angle perpendicular to the port septum to ensure proper placement through the center of the self-sealing membrane.
Question 3: A hemodialysis patient's tunneled catheter has recirculation rates above 10%. Which maintenance issue does this MOST likely indicate?
- Catheter-related bloodstream infection
- Fibrin sheath with reversal of arterial and venous ports (Correct answer)
- Lipid precipitate in the arterial lumen
- Catheter tip in the right atrium
Correct answer: Fibrin sheath with reversal of arterial and venous ports
High recirculation in a tunneled hemodialysis catheter often results from fibrin sheath formation or tip malposition causing reversal of flow between the arterial and venous ports.
Question 4: Which minimum syringe size should be used when flushing a CVAD to prevent catheter rupture from excessive pressure per square inch (PSI)?
- 1 mL syringe
- 3 mL syringe
- 10 mL syringe (Correct answer)
- 20 mL syringe
Correct answer: 10 mL syringe
A 10 mL syringe generates safe PSI levels for flushing CVADs; smaller syringes generate much higher pressure per surface area and can rupture the catheter.
Question 5: A patient receiving TPN through a PICC develops a triglyceride precipitate occlusion. The MOST appropriate clearing agent is:
- 0.1N hydrochloric acid
- Sodium bicarbonate 8.4%
- 70% ethanol dwell (Correct answer)
- Normal saline bolus flush
Correct answer: 70% ethanol dwell
Lipid (triglyceride) precipitates are best dissolved by a 70% ethanol dwell, which effectively breaks down fat-based obstructions in the catheter lumen.
Question 6: During a dressing change on a PICC, the nurse notices the external catheter length has increased by 3 cm since the last assessment. This finding MOST likely indicates:
- The catheter has migrated outward and the tip may no longer be in the SVC (Correct answer)
- Normal catheter elongation from IV fluid pressure
- The original measurement was documented incorrectly
- The patient's arm has grown since insertion
Correct answer: The catheter has migrated outward and the tip may no longer be in the SVC
An increase in external catheter length indicates the catheter has migrated outward, meaning the tip may have moved from its original optimal position and requires radiographic confirmation.
Question 7: A patient with a non-tunneled CVC develops fever and chills only during infusion through the catheter, but cultures are negative. This presentation is MOST consistent with:
- Catheter-related bloodstream infection (CRBSI)
- Infusate contamination (Correct answer)
- Catheter-related thrombosis
- Infusion phlebitis
Correct answer: Infusate contamination
Fever and chills occurring specifically during infusion with negative blood cultures suggests contamination of the infusate itself rather than a catheter-based infection.
VABC Maintenance & Troubleshooting of Vascular Access Devices 5
A pediatric oncology patient's implanted port is accessed for chemotherapy but there is no blood return despite easy flush.
Which action is CONTRAINDICATED?