Chapter 8: IV Therapy
8.8 Flushing and Locking PVAD-Short, Midlines, CVADs (PICCs, Percutaneous Non Hemodialysis Lines)
Critical Thinking Exercises: Questions, Answers, and Sources / References
- Describe your thought process as you determine what flushing protocol is necessary for a valved percutaneous CVAD non hemodialysis CVCs.
Answer: Think about the purpose of flushing IV cannulas: routine flushing is meant to prevent catheter occlusion. IV cannulas can become occluded from blood clots (fibrin) and / or build up of precipitates from meds, IV fluids including PN. In addition, proper flushing and locking might eliminate potential nesting material for microorganisms and as such reduce the risk of catheter related blood stream infections (Ferroni et al., 2014). The nurse needs to know what kind of venous access device the patient has, what solutions are being infused and how often, if the device is peripheral or centrally located, the number of lumens, and if the lumens are open (non-valved) or closed (valved). Generally CVC lumens are flushed before and after all IV meds. CVC lumens that are in use AND those not in use are routinely flushed. It is important to follow agency guidelines.
Think about the structure of the IV cannula: A valved CVAD has an internal mechanism to prevent blood reflux thus the use of an anticoagulant (heparin) is not necessary as part of the locking procedure. A valved CVAD has an internal mechanism to prevent blood reflux thus the use of an anticoagulant (heparin) is not necessary as part of the locking procedure.
Think about what guidelines are available in your agency: Agencies should have flushing protocols available to provide the nurse with guidance in relation to volume and frequency of flushing.
Think about add on IV equipment and what maintenance they need: The nurse must also understand the equipment available to them. Ie. what kind of needleless cap is being used. Neutral displacement and positive pressure valves (caps) can be used. Some syringes are specifically designed and if used correctly (remove the syringe before bottoming out) create the necessary positive pressure to prevent blood reflux into the catheter. This is important if the lumen will not have a continuous infusion running following the flush.
Some general guidelines include:
- Before use, CVADs should be checked for patency using a 10 ml or larger syringe containing saline.
- Patency is checked by aspirating. On a PICC, midline, and percutaneous non hemodialysis CVAD aspirating should reveal blood flashback into the tubing.
- 10 ml syinges of 0.9% NS should be used to flush CVADs to reduce the risk of catheter fracture. Smaller syringes have higher PSI thus risk of catheter damage.
- Always follow the manufacturer’s instructions when using needleless caps, as different techniques are required for different caps.
- The volume of the flush solution will depend on the volume of the catheter and any add on devices.
- Turbulent flush is a rapid stop-start or push-pause technique that is meant to clear the catheter of blood or drugs that may adhere to the inner lumen of the catheter.
- Cleanse the needleless cap before attaching and after detaching any syringe to reduce risk of infection.
- If no aspirate, reposition the patient’s arm (for PICC) or neck (other CVCs); assess the line for kinks; request patient take deep breaths, turn head and cough and/or perform Valsalva maneuver. If still no aspirate, change positive / neutral pressure cap. If still no aspirate consult PICC / IV team for possible declotting. Do not forward flush due to risk of dislodging thrombus from the lumen.
- Always clamp after removing syringe from the needleless cap. Positive displacement occurs in a neutral displacement cap when the syringe is disconnected from the cap before the syringe is completely emptied.
Sample flushing and Locking Protocol
| Vascular Access Device | Flushing and Locking Solution, and Volume | Frequency |
| CVAD, non-valved (e.g., percutaneous, tunneled, PICC) | Flush: 10 to 20 ml, 0.9% sodium chloride followed by
Lock: Heparin 3 ml of 100 units/ml |
Flush before and after each IV medication or access.
When retrograde blood observed Lock after each access, or weekly if not in use. |
Sources:
Anderson, R. (2018). Clinical Procedures for Safer Patient Care – ThompsonRiversUniversity Edition. Adapted from Clinical Procedures for Safer Patient Care by G. R. Doyle and J. A. McCutcheon. Chapter 8.8 Flushing and Locking PVAD-Short, Midlines, CVADs (PICCs, Percutaneous Non Hemodialysis Lines) https://pressbooks.bccampus.ca/clinicalproceduresforsaferpatientcaretrubscn/chapter/8-8-flushing-and-locking-pvad-short-cvad-picc-percutaneous-non-hemodialysis-lines/
Ferroni, A., Gaudin, F., Guiffant, G., Flauad, P., Durussel, J., Descamps, P., Berche, P., Nassif, X., Merckx, J. (2014). Pulsative flushing as a strategy to prevent bacterial colonization of vascular access devices. Medical Devices (AUCKL), 7. pp.379-383. doi: 10.2147/MDER.S71217
Interior Health. (2012). Parenteral practices manual. http://insidenet.interiorhealth.ca/Clinical/parenteralccr/Pages/Manual.aspx
Registered Nurses of Ontario. (2005) Supplement 2008. Nursing Best Practice Guideline: Care and Maintenance to Reduce Vascular Access Complications. http://rnao.ca/sites/rnao-ca/files/Care_and_Maintenance_to_Reduce_Vascular_Access_Complications.pdf
2. What is the purpose of using heparin to lock a non-valved (open) CVC?
Answer: open or non valved CVCs have no internal mechanism to prevent blood from entering into the catheter lumen when the lumen is not in use. The use of heparin (100 units / ml) in a volume advised by the manufacturer should prevent clotting of blood at the end of the CVC lumen thus allowing it to remain patent until it is next used.
Source: Interior Health. (2018). Transfusion practices manual. http://insidenet.interiorhealth.ca/Clinical/transfusionccr/Pages/manual.aspx
- The nurse checks patency of a PICC line prior to medication administration and doesn’t get blood returns. He / she should: (Select all that apply)
| distractor | answer | more info |
| Call the PICC nurse for declotting | Incorrect | This is only done after the other strategies are attempted |
| Reposition the arm | Correct | This should be among the first strategies you try when trouble shooting a potential CVAD occlusion) |
| Ask the patient to cough | Correct | This should be among the first strategies you try when trouble shooting a potential CVAD (PICC) occlusion |
| Ask the patient to perform the valsalva maneuver | Correct | This should be among the first strategies you try when trouble shooting a potential CVAD occlusion |
| Check the line for kinks & twists | Correct | This should be among the first strategies you try when trouble shooting a potential CVAD occlusion |
| Change the needleless cap | Correct | Suggest to try the other strategies first because they don’t require opening of the IV system. Thus less risk of complications (infection, air emboli). If all other strategies fail,change the needless cap. If the system still doesn’t appear patent, call the PICC nurse for further assessment and possible declotting. |
Source: Earhart, A. (2013). Central lines: Recognizing, preventing, and troubleshooting complications. American Nurse Today, 8(11). https://www.americannursetoday.com/central-lines-recognizingpreventing-and-troubleshooting-complications/
Interior Health. (2012). Parenteral practices manual. http://insidenet.interiorhealth.ca/Clinical/parenteralccr/Pages/Manual.aspx.
Registered Nurses’ Association of Ontario (RNAO). (2005) Nursing best practice guideline: Care and maintenance to reduce vascular access complications [Revised 2008 supplement]. http://rnao.ca/sites/rnao-ca/files/Care_and_Maintenance_to_Reduce_Vascular_Access_Complications.pdf.
2. What are the best practices for when PICC lines should be flushed? Select all that apply.
| Answers | More information | |
| a. Before & after meds | Correct | This allows removal of any fibrin & medication debris from the lumen and helps to ensure the lumens remain patent |
| b. After blood draws | Correct | This allows any removal of fibrin, blood residue from the lumen to reduce risk of further fibrin build up and helps to ensure the lumens remain patent |
| c. Q 7 days for lines that are capped | Correct | This allows any removal of fibrin and helps to ensure the lumens remain patent |
| d. Daily for lines that have continuous infusions | Correct | This allows for any removal of fibrin & med residue and helps to ensure the lumens remain patent |
Sources:
Interior Health. (2012). Parenteral practices manual. http://insidenet.interiorhealth.ca/Clinical/parenteralccr/Pages/Manual.aspx.
Registered Nurses’ Association of Ontario (RNAO). (2005) Nursing best practice guideline: Care and maintenance to reduce vascular access complications [Revised 2008 supplement]. http://rnao.ca/sites/rnao-ca/files/Care_and_Maintenance_to_Reduce_Vascular_Access_Complications.pdf.
3. What is the correct way to flush a PICC line? Select all that apply
| Distractor | Answer | More information |
| a. Push pause (turbulent flush) technique | Correct | |
| b. Gentle installation of 0.9% NaCl to prevent catheter rupture | Incorrect | Gentle installation may not create the force necessary to remove fibrin and medication debris on the catheter lumen |
| c. Installation of heparin with all lines | Incorrect | Only non valved (open) lines require heparin following the NS flush to prevent clotting at the end of the catheter |
| d. Aggressive forward flushing | Incorrect | Aggressive forward flushing may create excess pressure which can fracture the IV catheter |
Source: Registered Nurses’ Association of Ontario (RNAO). (2005) Nursing best practice guideline: Care and maintenance to reduce vascular access complications [Revised 2008 supplement]. http://rnao.ca/sites/rnao-ca/files/Care_and_Maintenance_to_Reduce_Vascular_Access_Complications.pdf.
4. What syringe size should the nurse use for flushing a central line?
| Distractor | Answer | More information |
| a. 3 ml | Incorrect | Syringes with lumens smaller than 10 ml create excess pressure which might fracture the catheter |
| b. 5 ml | Incorrect | Syringes with lumens smaller than 10 ml create excess pressure which might fracture the catheter |
| c. 10 ml | Correct | Syringes with lumens smaller than 10 ml create excess pressure which might fracture the catheter. syringes 10ml and larger are considered safe in relation to the amount of pressure they extert on the catheter |
| d. 20 ml | Correct | Syringes with lumens smaller than 10 ml create excess pressure which might fracture the catheter. Syringes larger than 10 ml are safe in relation to the amount of pressure they exert on the catheter |
Source: Registered Nurses’ Association of Ontario (RNAO). (2005) Nursing best practice guideline: Care and maintenance to reduce vascular access complications [Revised 2008 supplement]. http://rnao.ca/sites/rnao-ca/files/Care_and_Maintenance_to_Reduce_Vascular_Access_Complications.pdf.
5. The purpose of flushing a PICC or central line is: (Select all that apply)
a. To prevent fibrin build up (correct)
b. To remove medication residue (correct)
c. To clear the line of microbial agents (correct)
d. To determine patency (incorrect)
Source: Registered Nurses’ Association of Ontario (RNAO). (2005) Nursing best practice guideline: Care and maintenance to reduce vascular access complications [Revised 2008 supplement]. http://rnao.ca/sites/rnao-ca/files/Care_and_Maintenance_to_Reduce_Vascular_Access_Complications.pdf.
6. Use the following flushing and locking protocol to:
- Describe the flushing protocol for a PVAD short IV catheter . Answer in orange
- Describe the flushing protocol for a PICC line with open lumens. Answer in blue
| Vascular access device | Flushing and Locking Solution & volume | Frequency |
| PVAD-short | Flush and lock with 3 – 5 mL 0.9% sodium chloride | After each access or daily if not in use.
When retrograde blood observed |
| Peripheral Midline-Catheter
(non-valved) |
Flush: 5 – 10 mL 0.9% sodium chloride followed by –
Lock: Heparin 3ml of 100 units / ml |
Flush before and after each med / access
When retrograde blood observed Lock after each access or weekly if not in use |
| CVAD, non-valved (e.g. Percutaneous, Tunneled, PICC) | Flush: 10 – 20 mL 0.9% sodium chloride followed by –
Lock: Heparin 3ml of 100 units / ml |
Flush before and after each IV medication / access
When retrograde blood observed Lock after each access or weekly if not in use |
| CVAD valved
(e.g., Groshong®, PASV®) |
Flush and lock with 10 – 20 mL 0.9% sodium chloride | Flush before and after each IV med / access
When retrograde blood observed Lock after each access or weekly if not in use |
Copied from Anderson, R. (2018). Clinical Procedures for Safer Patient Care – Thompson Rivers University Edition. Adapted from Clinical Procedures for Safer Patient Care by G. R. Doyle and J. A. McCutcheon. Chapter 8.8 Flushing and Locking PVAD-Short, Midlines, CVADs (PICCs, Percutaneous Non Hemodialysis Lines) https://pressbooks.bccampus.ca/clinicalproceduresforsaferpatientcaretrubscn/chapter/8-8-flushing-and-locking-pvad-short-cvad-picc-percutaneous-non-hemodialysis-lines/
Sources:
Interior Health. (2012). Parenteral practices manual. http://insidenet.interiorhealth.ca/Clinical/parenteralccr/Pages/Manual.aspx.
Registered Nurses’ Association of Ontario (RNAO). (2005) Nursing best practice guideline: Care and maintenance to reduce vascular access complications [Revised 2008 supplement]. http://rnao.ca/sites/rnao-ca/files/Care_and_Maintenance_to_Reduce_Vascular_Access_Complications.pdf.