May 1, 2007
Insulin Pumps, Other
Question from Texas, USA:
I have a pump and a continuous glucose monitor. I was just wondering why pump sites cannot be left in for more than three days. Does more scar tissue occur if left in more than three days or is it the insulin that actually damages the tissue in that area? The main reason I am asking this was because I am not sure if this also applies to the CGMS sensor, as there is nothing being injected from the sensor. I realize that infection can occur and that sensors currently on the market are only FDA approved to be used for three days, but are there really any long-term effects from using a glucose sensor more than three days? Will the same thing happen with the sensors that happens when pump sites are left in too long, causing insulin resistance in that area?
Answer:
Pump catheters cause local irritation and can cause local infection from having a “foreign body” in the skin. The insulin also can act as an irritant. Both can cause scar tissue and thus interfere with insulin delivery and absorption. So, most of us suggest changing sites every 48 hours. Some can go longer, but you should review this with your diabetes team since they know what insulin you are using and what your sites actually look like already. The CGMS systems do not deliver insulin and so can go a bit longer. Some can go much longer than the three days suggested. Again, you should review this with your diabetes team so that you can get individualized advice. There could be the same general problem with infections and skin irritation/scar tissue from CGMS.
SB
