RN Exam Practice
Pharmacological and Parenteral TherapiesQuestion 1890 of 2368

The nurse flushes a central line that has a negative needleless connector. When should the nurse clamp the lumen?

  1. After the syringe has been disconnected from the needleless connector
  2. While injecting the last 0.5 mL, before disconnecting the syringe
  3. Before starting the flush, so that no fluid enters the catheter lumen
  4. No clamping is needed at any point for this type of connector
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Correct answer: While injecting the last 0.5 mL, before disconnecting the syringe

Clamping before disconnection prevents blood from flowing back into the catheter tip. Positive connectors are clamped after disconnection.

Source: Nursing Advanced Skills (Open RN, Chippewa Valley Technical College, 2023), Manage Central Lines: Flushing and Locking CVADs. Licensed under CC BY 4.0.

Practice the topic "Pharmacological and Parenteral Therapies"

Questions last reviewed: 18 October 2026