Question

Hello Rabbi,
Suppose someone drives a critically ill patient to the hospital on the Sabbath. After dropping off the patient, what is the proper way to conclude the trip? I saw the following written online:
At the end of the trip, since there is a concern of danger in leaving the engine running or leaving the keys in the ignition switch, because someone might enter the car and cause an accident, there is room to permit turning off the engine and removing the keys from the ignition switch. This should be done in an unusual manner, for example between two fingers.
The problem is that, as far as I know, there is no real danger in leaving the engine running, or in leaving the key in the ignition when the car is off. Besides, if you turn off the car there is still the problem of carrying the car key, since it is muktzeh. I thought that perhaps there is room to permit it so that people will not refrain from driving sick people to the hospital out of concern that after the trip the car will be at risk. How do you think one should act here?
Best regards,