I do it anytime it is obviously indicated, anytime I start a line, and on all medical calls. BGL can be indicative for more then just mental status; people having MI's may not show on the ekg but a high BGL can be indicative. As the muscle tissue dies it releases glycogen stores which increases BGL, so non-diabetics with abnormally high BGL should get a second look. Treat the pt not the monitor...one more thing to throw into the bag of tricks. Like everyone else is saying, it is non-invasive and can help you out. I would also point out that checking off your IV stick should be done carefully, some BGL monitors ar specifically for capillary blood. My rule of thumb is if it reads high/low check it off a finger also...BGL of 120 off a IV stick is good enough for me though.