many years ago I was flown to Europe, as I was bedridden, for treatment, c.q. operation.
flew on commercial flight, was carried on and off by airport staff, including at a stopover and change of planes. (only time I entered the plane on the lift of a catering truck 555) One accompanying person sat somewhere nearby.
Stretcher occupied 6 or 8 seats, do not remember.
That was at the time charged as 7 (or 9) seats plus ground transport-ambulance , not hundreds of thousands.
Having said that, I did not need a drip or other medical care during the flight.
Just a double vodka and a sleeping pill .