Coincidentally, LA City Fire Dept station 51 is located on-site at LAX and Rescue Ambulance 51 would be first due to respond to a medical emergency on an inbound flight.
Beginning with this first episode of the fifth season, the radio station where the doctors communicate with the paramedics was moved from the corner of the nurse's station to its own separate alcove.
Station 127, AKA Station 51, is located at 2049 East 223rd Street, Carson, CA. It is just over 15 miles from LAX. According to google maps the trip would take 27 minutes in a no traffic condition. Even running full code, the trip would take a long time and take the squad away from its area.
First episode where the Dispatcher is actually seen.