A nurse is preparing to draw a blood specimen from a client's multi-lumen central venous catheter (CVC). The selected lumen is currently capped and not actively infusing any fluids. In what order should the nurse perform the following actions to safely obtain the specimen, prevent infection, and maintain catheter patency? Arrange the steps in the correct chronological sequence.
- 1Scrub the needleless connector hub with an antiseptic swab and allow it to dry.
- 2Flush the catheter lumen with 5 to 10 mL of normal saline to assess patency.
- 3Aspirate and discard a 5 mL waste sample of blood.
- 4Withdraw the required volume of blood for the laboratory specimen.
- 5Flush the catheter lumen using a pulsatile technique with 10 to 20 mL of normal saline.
Answer
The correct sequence for safely drawing blood from a central venous catheter is to first disinfect the hub, flush to check patency, discard a waste sample to clear the line, withdraw the actual specimen, and finally flush vigorously to clear residual blood.
Drawing blood from a central venous catheter requires a strict sequence to prevent infection, ensure patient safety, and obtain accurate diagnostic data. Disinfecting the hub is the critical first step to prevent CLABSI. Flushing assesses patency to avoid applying negative pressure to a blocked line. Discarding a waste volume is essential to clear the lumen of any flush solutions or medication residue that could alter the laboratory results. After drawing the uncontaminated sample, a generous volume of normal saline must be flushed using a push-pause (pulsatile) technique to completely clear the viscous blood and prevent catheter thrombosis.
Step-by-Step Solution
Key Concept
Central Venous Catheter (CVC) Blood Draw Protocol