Hey Katie,
IMHO, flying can be difficult, maybe more so than driving. Driving you can lay the seat down taking all or most of the stress off your neck and back or even lay down in the back seat with pillows wherever you need them (seat belts please). Flying includes getting to the airport, waiting to go through security, waiting for your flight, waiting for clearance after boarding, waiting for your baggage, and driving to the hospital, and then the reverse. I know the flight is so much shorter and the trip is broken up into small segments but overall, I think driving might be more comfortable - if you're looking for an excuse to drive
Dale