or heparin locks (
once called heparin wells)
are merely peripherally placed iv devices that have no iv tubings or iv solutions continuously attached to them. they are iv cannulas that are capped. in order to maintain their patency (freely open and functional) they must be (1) capped off, and (2) primed with a solution to prevent blood from entering the shaft of the cannula of the iv device and clotting it off so it looses its patency. saline and weak solutions of heparin are used to accomplish this.
maintenance includes regularly monitoring and caring for the iv site and the equipment attached to it in order to avoid complications (infection, phlebitis, infiltration).
- the iv site should be assessed every 1 to 2 hours (this is an ins-intravenous nurse's society--standard)
- you should know the type and length of the device that has been inserted because this determines the area of the patient's arm that you need to examine (the length of the vascular device should be documented on the dressing)
- assess for the presence of any pain or tenderness which is a precursor of phlebitis
- assess for swelling at or above the venipuncture site even if you are able to ascertain a blood return. if in doubt that swelling is present have the patient hold both arms together and compare them visually.
- if there is a transparent dressing properly positioned so the insertion site is observable you should be able to assess for much of the following:
- assess for blanching (white, shiny appearance) at and above the insertion site. this is a sign that infiltration of injected solution has occurred
- look for the leakage of any fluid from the insertion site or the skin surrounding the length of the iv device. this is a sign of infiltration or cellulitis.
- assess for redness at or above the insertion site. this is a sign of phlebitis.
- the iv device should be removed and placed in another location if there is any evidence of pain, tenderness, phlebitis or infiltration
- the iv device should be removed and placed in another location after 72 hours (this is an ins standard)
- a dressing should only be changed if it is soiled, wet or the iv site is being changed. disturbing the dressing that was placed at the time the iv was inserted increases the likelihood of phlebitis occurring and the introduction of bacteria. ivs should not be remaining in place longer than 72 hours.
- it is done as a sterile procedure
- once the old dressing is removed, assess for redness, swelling, leakage and any streaking - if any is found, d/c the iv device
- otherwise, carefully clean around the iv site with providone-iodine or alcohol using a circular motion working from the center and moving outward
- allow the area to air dry
- re-tape the device in place
- apply the new dressing so that the iv site can be seen
- mark the dressing with the date the iv was inserted, the type and length of the catheter, the date of the dressing change and your initials
- document your observations and the dressing change in the patient's chart
- the changing of the cap on the device is usually done at the time of a dressing change. it can be changed if it is gunky with blood. remember it is a point at which bacteria can be introduced into the patient so it should be a sterile procedure. to prevent backflow of blood from soiling everything, place a sterile 2x2 below the hub of the cannula and using the finger of one hand place pressure over the vein at the point where the tip of the end of the cannula will be seated in the patient's vein. this will occlude backflow of blood into the cannula as you remove the old cap. make sure the new cap is tightened sufficiently. flush.
- a saline or heparin lock should be flushed on a regular basis to maintain its patency. every facility will have a protocol for flushing the saline lock. flushing the lock is how you maintain the patency of the device. documentation of flushing is usually done on the mar (medication administration record)
- this is what ins and roxanne perucca, rn, crni has to say about flushing: "when a vascular device is flushed, positive pressure must be maintained on the lumen of the cannula to prevent reflux of blood into the cannula lumen. positive pressure is maintained by keeping a forward motion on the syringe plunger as the needle is removed from the injection port. if resistance is met during flushing, no further attempts to flush should be made. pressure should not be exerted on the catheter to restore patency; applying pressure to an occluded catheter can dislodge the clot into the vascular system or rupture the catheter. . .the cannula should be flushed when [it] is left in place for intermittent therapy. if a catheter is capped off and no medication is being administered intravenously, the catheter must be flushed to maintain patency. the frequency of flushing. . .varies from institution to institution. . .many institutions have established standardized flushing protocols to be used for various vascular access devices." (page 398, intravenous therapy: clinical principles and practice, by judy terry, leslie baranowski, rose anne lonsway and carolyn hedrick, published by the intravenous nurses society, 1995)
- this is the flush policy from the facility where i last worked on an iv team:
iv and central line catheter flush policy xyz hospital
sas - saline - antibiotic (or other medication) - saline
sash - saline - antibiotic (or other medication) - saline - heparin
peripheral iv - flush with 1 cc of normal saline q8h. sas before and after meds.
non-tunneled central (triple lumen catheter) - flush with 2.5 cc of heparin (100 units/cc) daily per each lumen. sash before and after meds.
hickman - flush with 2.5 cc of heparin (100 units/cc) daily. sash before and after meds.
groshong - flush with 5cc's of 0.9% normal saline daily. sas before and after meds.
picc - flush with 2.5 cc of heparin (100 units/cc) daily. sash before and after meds.
groshong picc - flush with 5cc's of 0.9% normal saline daily. sas before and after meds.
implanted port - flush with 2.5 cc of heparin (100 units/cc) daily. sash before and after meds.
references: intravenous therapy: clinical principles and practice
, by judy terry, leslie baranowski, rose anne lonsway and carolyn hedrick, published by the intravenous nurses society, 1995; nurse's 5-minute clinical consult: procedures
from lippincott williams & wilkins.
the ins (intravenous nurse's society) writes the standards for iv therapy and most facilities try to follow them. facilities have policies and procedures that usually reflect these standards as do most nursing textbooks that address iv therapy.
here is an online example of one hospital's policy on how saline/heparin locks are to be maintained:
you can also see a video of how an iv is converted to a saline lock on this website: http://saddleback.edu/alfa/vid_index.aspx
both of the above websites were found from the links posted on this sticky thread in the nursing student assistance forum: http://allnurses.com/forums/f205/any...es-127657.html
- any good iv therapy or nursing procedure web sites