"We are required to respond to any call with lights and sirens ..."
Wow scoobymedic I have never heard of that. Here in QLD we have 3 response codes: 1(time critical), 2(acute non time critical), 3 (non urgent). In my experience I have ever only done one code 3 and it was transferring a discharged pt from hospital to his home. Code 1 is a lights and sirens response where at the least the lights are to be activated (many just use sirens in traffic). Code 1 accounts for things such as chest pain, syncope, RTC/MVA, difficulty breathing, major haemorrhage, ALOC, seizures, etc. Code 2 accounts for things such as post syncope, abdo pain, minor haemorrhage, fractures, inter hospital transfers, etc.
In regards to transferring to hospital we have the choice whether to go code 1 or 2 and it is quite rare for us to go code 1. In regards to interhospital transfers we get dispatched either code 1 or 2 and that is what we transfer as. On rare occasions we go code 1 and if we are code 1 we generally have a Dr and RN on board.
It's quite interesting to see how the different EMS systems around the world work.