Mishap at my nearest A&E you're met by a triage nurse in the lobby, but the ambulance crew stay with you until you're wheeled into cubicles. Sometimes the paramedic is sat around twiddling his thumbs waiting for the ambulance to arrive, too. The whole system backs up all the way down the line.
My first time was the longest wait because they were busy with a local pop festival:
10.35 doctor calls ambulance,
11.26 paramedic arrives,
11.36 calls ambulance,
12.11 control ask if ambulance is still required, then offer an upgrade to Red1,
12.27 ambulance arrives,
12.49 ambulance departs,
13.18 arrive A&E,
13.40 into cubicles (& crew depart),
13.55 into Resus.
Total time, 999 - Resus: 3h20