activating Siri without hand contact

Setting:

- operating room
- sterile gloves on
- mask, coat...

Basically I cannot touch anything with my hands. Elbows are also out of the picture. Feet are an option. Also there can't be any wires, the phone is around 4-5 meters away, so bluetooth would be my best bet.

I would like to find a device, which I could use to somehow trigger iPhone / Siri. Changing music, making phone calls, reading and replying to messages.

I thought of putting a normal BT headset in a sterile bag, but problem would be having to change the bag for every procedure. Not very practical.

Ideally this would be some kind of beam, which would cross the operating table and I could interrupt with my hands in air and which would replicate the press of the home button (like on three button headsets).

Does anything similar even exist?

 

Implanting (accidentally) a BT headset would be borderline cool. The headset pairing everytime the pacient comes for a check-up.

I've checked the handsfree app on Cydia, but there are two problems: I have 6.1.4 (and no intent to jailbreak in the future) and the other one is, that there is no voice recognition when music is playing. I would connect the iPhone with the stereo system in the OR to listen to music.
It would be simple to mount a BT headset on the ceiling lights and just talk into it.

Any other ideas?