Ch 15: Fluid, Electrolyte, and Acid-Base Balance - Changing the Dressing and Flushing a Central Venous Access Device (CVAD) (Video Available on Course Point - 11:32)

The nurse is collecting a blood sample from a central venous access device (CVAD). How much blood should the nurse collect in the discard tube?

5 mL Rationale: The nurse should collect at least 5 mL in the discard tube to ensure a clean blood sample. Discarding any amount less than 5 mL may result in a contaminated blood sample.

The nurse is inserting normal saline into the lumen of a central venous access device (CVAD) prior to obtaining a blood sample. What recommended amount of saline should the nurse use to flush the line?

5 to 10 mL Rationale: The nurse should insert 5 to 10 mL of normal saline into the lumen to flush the CVAD. This helps to ensure the collection of a fresh blood sample. Less than 5 mL is inadequate to ensure a fresh sample. More than 10 mL is unnecessary.

The nurse is caring for a client who is receiving total parenteral nutrition. While changing the dressing of the client's central venous access device (CVAD), the nurse cleanses the site with chlorhexidine. Which action would the nurse perform next?

Apply skin protectant to the same area, avoiding direct application to the insertion site. Rationale: After cleansing the site with chlorhexidine, the nurse would allow the site to dry completely without wiping or blotting the area. The nurse would then apply skin protectant to the same area, while avoiding direct application to the insertion site, and allow it to dry. Skin protectant improves adhesion of the dressing and protects the skin from damage and irritation when the dressing is removed. After applying skin protectant, the transparent site dressing or securement device would be placed over the insertion site.

The nurse, drawing a blood sample from a client's central venous access device (CVAD), is unable to start the blood flow, despite trying a new specimen tube. What would the nurse do next to try to start blood flow?

Ask the client to raise the arm and cough. Rationale: If blood does not start flowing when drawing blood from a CVAD, the first action is to try a new specimen tube, because these tubes may be defective. If the new tube does not work, having the client raise the arm above the head and giving a cough will often start the flow. Flushing with either heparin or saline would alter the blood specimen and should not be done. Placing the arm below the level of the heart is not effective for starting blood flow.

When preparing to change the dressing of a multiple lumen central venous access device (CVAD), which action does the nurse take to prevent air embolism?

Clamp each lumen Rationale: The nurse would clamp off each lumen to prevent air from entering the catheter and causing an air embolism. Sterile technique is used to prevent infection. Flushing the lumens with normal saline solution verifies patency. Placing the client flat, with the arm below the level of the heart reduces the risk of air embolism.

The nurse is collecting a blood sample from a client's central venous access device (CVAD). The nurse notices that the flow stops when drawing the blood, even after changing the specimen tube and having the client cough. What would be the next recommended intervention?

Clamp the tubing, remove the tube and vacutainer, and flush with normal saline. Rationale: If the blood does not flow after changing the specimen tube, the nurse would clamp the tubing, remove the tube and vacutainer, and flush with 5 mL normal saline. The nurse would then redraw a waste sample and attempt to finish collecting the blood sample. Heparin would not be reinstilled, as it would change the viscosity of the blood. It is important to clamp the tubing before removing the tube and vacutainer to prevent air embolism.

The nurse has collected a blood sample from a client's central venous access device (CVAD). After removing the vacutainer, what should the nurse do next?

Flush the line with normal saline. Rationale: After collecting the blood and removing the vacutainer, the nurse should flush the line first with normal saline, then with heparin. The line is not flushed with sterile water and the blood sample tube is labeled after flushing the line.

When changing the dressing of a central venous access device (CVAD), how should the nurse remove the old dressing?

Lift it distally, and then work proximally to the insertion site while stabilizing the catheter with the gloved finger of the nondominant hand. Rationale: When changing the dressing, the nurse would remove the old dressing by lifting it distally and then working proximally, making sure to stabilize the catheter with the gloved finger (clean gloves) of the nondominant hand. These steps help to maintain aseptic technique during the procedure. The gloved finger provides more stability to the catheter than an antimicrobial swab.

After removing the dressing of a client's central venous access device (CVAD), the nurse notes dried blood at the catheter insertion site. What is the next action by the nurse?

Put on sterile gloves and cleanse the dried blood using a sterile antimicrobial wipe in a circular motion beginning at insertion site and working outward. Rationale: While wearing sterile gloves, the nurse would wipe off any old blood or drainage with a sterile antimicrobial wipe, starting at the insertion site and continuing outward in a circle. Sterile gloves are used after removing the dressing to prevent contamination of the insertion site. Wiping the site from the outside to the inside could introduce microorganisms into the site. The dried blood must be removed before cleansing with chlorhexidine to prevent organisms from being introduced into the tissues.

When the nurse is drawing a blood sample from a client's central venous access device (CVAD), the blood stops flowing after the collection tube has been placed. The nurse removes the tube and flushes the lumen with 5 mL of saline solution. What is the next action by the nurse?

Redraw the waste sample. Rationale: After flushing the lumen with 5 mL of saline solution, it would be necessary to redraw a waste sample before attempting to collect the sample. If the waste sample is not drawn at this point, the blood sample may be altered by the saline solution. Flushing with heparin would be done after the sample is collected. It is not necessary to notify the health care provider until all efforts to obtain the sample have been exhausted.

The nurse is observing an unlicensed assistive personnel (UAP) drawing a blood sample from a client's central venous access device (CVAD). After the collection tube has been placed, the blood stops flowing. Which action by the UAP would require the nurse to intervene?

The UAP flushes the lumen with 5 mL of sterile water. Rationale: The nurse should intervene if the UAP flushes the lumen with 5 mL of sterile water. When drawing a blood sample from a client's CVAD and blood stops flowing after the collection tube has been placed, the UAP should first replace the specimen tube, because these tubes are sometimes defective. If blood still does not flow, the UAP should ask the client to raise the arm and cough. If additional intervention is still required for starting the blood flow, the UAP should clamp the tubing, remove the collection tube and vacutainer, and 5 mL of saline solution, not sterile water.

The nurse is collecting a blood sample from a client's central venous access device (CVAD) and notices that the flow stops when drawing the blood. What should the nurse do first?

Try a new specimen tube. Rationale: If the flow of blood is slow or stopped, the nurse would first try a new specimen tube, because these tubes are sometimes defective. The tubing is not clamped when drawing a specimen. Pushing down on the access needle and raising or lowering the head of the bed are helpful when meeting resistance in flushing a CVAD.

The nurse turns off an intravenous (IV) infusion and waits for 1 minute before obtaining a blood sample from the client's central venous access device (CVAD). For what client would this sequence of actions be appropriate?

a client receiving a standard IV solution Rationale: The nurse should turn off an intravenous (IV) infusion and wait for 1 minute before obtaining a blood sample from a client receiving a standard IV solution. The nurse should wait for 5 minutes if the client were receiving heparin, TPN, or any other solution that alters laboratory results.

The nurse is preparing to change the dressing for a client with a peripherally inserted central catheter (PICC). At what point would the nurse assess the insertion site?

after putting on clean gloves Rationale: The nurse assesses the insertion site of a central venous access device (CVAD) through the old dressing after putting on clean gloves. Care to the site is completed once the old dressing is removed. Site care includes cleaning the site and applying a skin protectant.

A nurse is preparing to draw a blood sample from a central venous access device (CVAD) that has more than one lumen. Which lumen is most appropriate for the nurse to use to take the sample?

distal Rationale: The nurse should use the distal lumen when drawing blood samples from a CVAD, when possible. The length of the lumen is not a determinant in this decision. The proximal lumen should be used only if the distal lumen is unavailable.

The nurse is caring for a client who has a peripherally inserted central catheter (PICC) in place to receive antibiotics. As the nurse prepares to change the dressing of the PICC, how should the nurse position the client?

lying flat, with the arm extended from the body below heart level Rationale: The nurse would assist the client to a comfortable position that provides easy access to the central venous access device (CVAD) insertion site and dressing. Because this client has a PICC, the nurse would position the client lying flat, with the arm extended from the body below heart level. This position is recommended to reduce the risk of air embolism. Sitting upright does not reduce the risk of air embolism.

A nurse needs to obtain blood samples for lab studies to check the electrolyte levels for a client who has a multilumen non-tunneled percutaneous central venous catheter in place. The client is receiving intravenous (IV) fluids through the central venous access device (CVAD). What should be the nurse's first step in this procedure?

urn off the flow of fluids to the CVAD. Rationale: First, the nurse should turn off the flow of fluids to the CVAD, and then wait for the specified amount of time. There is not a "hold" button on the CVAD, and the device is not flushed with normal saline. Increasing the flow of fluids should be inappropriate.