The answer - a waterproof "case" called a Frog Skin.
How does it work? Here's a goofy You Tube video that demonstrates the product.
Frog Skins are available for all the iDevices (iPhone 3GS/4, iPad/2). They are not actually a case, but rather a film-like covering that is clear and wraps around. the device. We tested it by making a phone call in a glass of water. They are completely waterproof, but probably not under pressure.
But can you sterilize an iPhone/iPad for use in the Operating Room?
Here's Dr. Henry Feldman's description:
Last night we ran the big experiment, and placed a Frog Skin encased iPhone 3G in an ethylene oxide sterilizer (for surgical instruments that can't go in an autoclave). We sterilized the iPhone. The cycle was 6 hours of gas time, and 12 for outgas. I turned the phone off, so no activity would occur causing heat or a spark, since ethylene oxide is flammable. I placed a gas detection strip inside the Frog Skin and one inside the sterile pack. The pack was placed in the sterilizer with all the other surgical instruments.
The photo above shows the iPhone inside the sterilization package (as it would be delivered to the Operating Room). Note that both tags have turned blue. This means that gas got inside the Frog Skin. The entire iPhone is sterile as the Frog Skin does not stop the gas. The phone booted without problems, and operates fine inside the skin. In summary, eth-ox doesn't affect the iPhone in any way. The Frog Skin (polypropylene) does not stop the eth-ox form getting to the phone but will prevent Operating Room liquids from getting into the phone. And yes, you can operate the phone with gloves and the Frog Skin on.
That being said, putting an electrical device inside of an explosive gas atmosphere is done at your own risk! (this is a oxygen depriving unit, so there should not be a fire possibility, although during outgas time there may be a risk)
We now have an iPhone/iPad solution for wet, messy health care environments, even in the Operating Room. That's cool!