Gingernut: Whilst an aviation forum may not be the optimum place to glean medical opinion, there has certainly been a good spread of responses!
The debate over the 'golden hour', 'stay and play', 'scoop and run', etc. has still to find a definitive answer. As with much in life, it often depends on the exact situation/circumstances - a hypothermic survivor from a hillside or the sea probably needs to be in the nearest hospital as soon as possible to get re-warmed in the most timely manner; the head injured patient needs an RSI and transfer to a neruo-surgical centre. Delays on scene may or may not be justified.
Essentially it boils down to getting the
correct resources to the
correct patient who must be transferred to the
correct hospital in the
correct time frame. Thus, air ambulances play their role in either getting expert resources (paramedics or doctors) to the incident scene or over flying 'local resources' to transfer the patient to definitive care (i.e trauma centre). Morbidity and mortality is known to increase for every subsequent transfer a patient is subjected to after reaching the first place of medical care...
London (and other large metropolitan districts) provide specific challenges - e.g getting expert care on scene in a timely manner. Getting to definitive care may well be most effectively achieved by then utilising road transport - this does not negate the need or usefulness of an air ambulance but requires a different mind set. It is certainly less dramatic arriving at hospital by ambulance than a helicopter, but this doesn't mean the HEMS system has not played a part!
Careflight in Sydney have been undertaking a trial with head injured patients which (from my understanding) attempts to address the question of the role of physicians in pre-hospital care. I believe that whilst the teams are flown to scene, the subsequent transfer is often (but not exclusively) by road. More details on their website:
CareFlight - Head Injury Retrieval Trial (HIRT)
Does anyone have any idea if there are any studies that demonstrate a difference in outcomes depending on who is on board?
There are studies looking at this area but they generally recruit small numbers with an associated difficulty in reaching statistical significance - there was a recent thread which touched on this area with a link to some medical articles. Trying to 'match' trauma cases for research purposes is notoriously difficult, costly and thus limited.
If you want more details or specific answers to the questions you posted regarding protocols/advanced practice/etc. I suggest you PM me - after all, as has been pointed out, it is a helicopter forum!
Simon