Like DDU posted, "it depends" is the answer.
It depends on the hospital, the doctor's office, type of visit, appointment, emergency, location, availability of interpreters, cost, time of day/night, deaf patient's needs, etc.
Some hospitals and doctors are more willing to get terps than others. Some use private practice (freelance) terps, some use state or private agencies, and some (wrongly) try to get family members to interpret. Some say, "read my lips."
There is no one answer that covers every situation.
