You might consider stocking oral rehydration solution as an alternative to IV supplies. A trained person isn't necessary, which is important if you are not around to administer the IV or otherwise not able to do it (e.g. what if your strong hand were injured?). Of course, in situations when you really need fluids fast, you need an IV, but for conditions like dehydration from vomiting/diarrhea, a supply of ORS should suffice and can be prepared by anyone.