Care and Maintenance to Reduce Vascular Access Complications

Nursing Best Practice GuidelineCritical ThinkingRemember to heparinize the device not the client. Some clients that require a significantvolume or concentration of Heparin locking solutions may experience complications. Considerwithdrawal of the heparin lock prior to flushing to reduce the amount of heparin a client receives.While this is practiced in some settings, there is no scientific evidence to support this recommendation.The panel offers this as an option that could be considered based on the risks and benefits for someclients at high risk of device occlusion.2. Concentration of SolutionThe concentration of the flushing or locking solution relates to the use of heparin. The heparin used shouldbe the lowest therapeutic concentration (e.g., 10 IU/mL) and have the smallest volume that will maintainpatency relative to the internal volume of the device (DH, 2001b; INS, 2000; RCN, 2003).3. Volume of SolutionFlushing: Nurses will use sufficient volumes of flush solutions to clean the internal lumen of the device(3-5 mL for PVAD and 10-20 mL for CVAD). The volume after blood withdrawal and medicationadministration should be at least 20 mL for all VADs. Macklin (1997) concludes that problems may occurwith too little flush solution but not with too much.Locking: The volume should be at least twice the volume capacity of the catheter lumen (usually between3-10 mL for all devices (Macklin, 1997)) plus the priming volume of all add-on devices of the infusion system(e.g., extension tubing) (INS, 2000).4. Frequency of AdministrationGenerally, flushing shall be performed:■ After blood sampling;■ When converting from continuous to intermittent therapies;■ Before and after medication administration;■ Before and after administration of blood components;■ Before and after intermittent therapy; and■ For maintenance of a dormant device (INS, 2000; RCN, 2003).Frequency of device use often determines the frequency of flushing and locking. Devices usedintermittently are flushed before administration and are flushed and locked at a minimum after everyinfusion or medication administration. The schedule of catheter flushes varies among practice settings andamong indwelling devices (Ray, 1999). Despite this, VADs should be flushed and locked at establishedintervals to maintain patency and to prevent occlusion.Table 2 summarizes the recommended flushing and locking interventions related to VAD tip position andtechnology.31