I feel very torn

I am really struggling with this, so much so that I've erased this a dozen times. I am on the old side, and a severe asthmatic who has had seven bouts with pneumonia in my life. The position I'm working in now is at the point of asking staff to please volunteer to float to a sister facility caring for a great number of COVID patients, as they just don't have enough help. They haven't asked me yet, and this could be because I live over two hours away, and there is basically no one else to serve in my role if I go that far away to fill a staff slot. But I have a feeling the request will soon not be a request, it will be mandatory rotation (if they can find someone else to 'be me' while I'm off somewhere else.) I have had people both nurses and non-nurses telling me to please, be up front with the powers that be about how shot out my lungs are, if it comes to that. But I can't reconcile myself with that. If everyone who had a serious medical issue did that, where would that leave us as a whole? I have people telling me I didn't agree to sacrifice my life for being a nurse, but something in me kinda says that I did. The PPE situation would also be dicey, at best, I am fairly sure, but that's not a situation unique to me, by far. I really wish I had paid more attention in that ethics class. Thanks in advance.