Being the mother of a doctor gives me another perspective on this issue. If it was a request from a doctor herself, she more than likely had a polyester fabric in mind BECAUSE:
1. She'll likely be using this instead of her white coat while seeing patients
2. Blood/body fluids wash out of polyester/blends easier.
3. It doesn't wrinkle which means it "appears" fresher.
4. It's easier to stain-treat, wash, rinse, and hang to dry if facilities are limited.
I'd definitely ask her for more guidelines about what she had in mind before you spend the time making these.
Jan in VA