Quick question IVs

Originally, they were called "Heparin wells" because the device (the IV cannula or needle with all IV tubing removed and merely capped off) was then filled ("closed" or "locked") with a diluted solution of Heparin. Then, they came to be known as Heparin locks because the small amount of solution was locked into the device and just sat there keeping it patent. Over time it was discovered that a Heparin solution was not needed to keep these devices patent and that saline worked just as well. They couldn't rightfully refer to them as Heparin locks, so the term "saline lock" was used. So, technically, yes, there is a difference between a Heparin lock and a saline lock. One will be "closed" with Heparin and the other with saline. However, the two terms have come to be used so commonly that many times you will hear a nurse use the term "Heparin lock" when saline has actually been used to close the device. It's kind of like the word "Kleenex" being used to refer to all brands of tissue. If you are in doubt as to what solution is in the device refer to the medication sheet or the doctor's orders, or ask.