Northern Virginia has several health care centers (affiliated with Inova) that are on bus routes or near our Metro (subway) system. There's also George Washington University Hospital in Washington DC (right on the Blue and Orange Metro lines, both that begin in and have several stops in Northern Virginia) and several other medical centers in DC right on bus routes and Metro lines.
If you'd like additional information, please don't hesitate to let me know. My email is firstname.lastname@example.org and phone number is 703-451-0677.
Have you tried going to http://www.gohrt.com. We have The Tide that has been running a couple of years now and actually have a a couple of hospitals not to far from it . (Sentera) Really going off that Newtown area you can hit about 6 hospitals within 6 miles.