Blood is mostly made up of water, as are our organs and muscles. To read specifically about edema, swelling caused by fluid retention where excess fluid is trapped in the body's tissues, see our article Edema: Causes, Symptoms and Treatments.
If you use the Amsoil Ea15K01 and the ASM oil (For 3rd gen Prius), then you can safely go 15,000 miles between oil changes. I drive 25,000 miles per year in my Prius. Amsoil backs up their products by a written warranty.
2010 Prius Maintenance - Changing Oil 4 of 18 Last Updated: 9/09/2009 Before lifting the vehicle you must find a level surface to do the work. Once you drive the Prius there, engage the parking-brake (shown below) by depressing the pedal all the way.