1. I've seen them flush the machine/tube between people but you might ask your industrial hygienist for more details.
2. Depending on your ICU set-up it may well be floating around and coating a lot of surfaces. Aerosol generating events (intubations, mask nebulizers, high flow nasal cannulas) should be done in negative pressure rooms only, especially if not everyone in the unit is wearing N95s all the time. If you're re-using the mask for the week I would wear a surgical mask over the top of the N95 to reduce the fomites. Look for Youtube videos on how to doff an N95 into a tupperware container as the outside is considered contaminated. If they are not providing eye protection bring your own faceshield, onion goggles, lab goggles, etc. Consider getting a headband for the surgical mask, the nurses likely already have them and they have 2 buttons sewn to the sides so you don't have to use your ears. Obviously these need to be washed daily so you'll need at least two.
Use every hand sanitizer dispenser you walk past while in the ICU, usually this is also less caustic on your hands because most of the hospital sanitizers contain some moisturizer. Wash your hands before and after going to the bathroom and before and after eating. Don't touch your face. Wear at least a surgical mask 100% of the time while in the hospital unless you're actively eating or drinking something. Sanitize your hands frequently, no seriously. Unless you're being exposed to a lot of high risk aerosol events your hands are the most likely vector.
Watch either your hospital's, the CDC's or a random Youtube video you like on how to don and doff PPE. Watch it over and over until you're sick of it and then watch it some more. Doffing is the most dangerous part as you're now likely covered in covid. Use a buddy if you can. The nurses will likely be able to help you as they've probably been doing it more than you. Once you're comfortable donning/doffing, forget that you're comfortable. Familiarity breeds contempt and that's risky.
For codes full PPE goes on (N95, full faceshield, hair/head cover, isolation/surgical gown, double glove, booties if available) and only then do you go into the room and only if you're actually going to physically do something. This is an absolute.
3. If your hospital is providing hotel rooms (some are) you could consider it. Wear scrubs/clothes to work, change into hospital scrubs for work including covid shoes that stay in the hospital. Zip lock baggie your phone, dispose of this bag as you are exiting the hospital. Change your scrubs before leaving the hospital. Carry as little as possible into the hospital and bring as little as possible into the house (phone, house + car key, license, credit card). Shoes stay outside. Strip before entering the house if feasible. Go immediately to your own shower. Use bags to bring clothes to the washer directly and dispose of those bags outside the house right away. Wash everything in hot water. Wipe anything you brought to the hospital down with bleach wipes and try to leave it in your "hot" zone by your door. Sleep in a separate room, don't share food or bathrooms and take your temperature morning and evening if you're staying with older people.
