Cabin temperature.
Sorry to hear of your condition. The cabin can be carried at any temperature, however the problem is that it will be inconvenient to the other passengers. Apart from asking all the other passengers to wear warm clothing for the 21 to 22 degrees that you require I cannot think of how to solve your problem besides if you charter the plane for you alone. If it is a short flight you may get the passengers agree to 22 degrees for the duration of the flight.