Many years ago I was well trained first aider and have dealt with a whole range of issues…….oddly as a first aider the one ailment I struggle with dealing with is people throwing up!!
Anyway, your point about doctor versus paramedic is valid…….to a degree….
Our highly respected and ancient St. Andrews trainer, advised us to be assertive and take charge at a scene…..including if doctor was already tending…..His reasoning was Doctors are trained to care for the patient First aiders are there to stabilize……
For those telly addicts out there, the analogy I would use is from the programme MASH…….the wounded were dealt with at the front line station by paramedics, then transported to the MASH unit….A doctor would just over complicate matters at the front line !!
On an aircraft I would have thought that the CC are trained enough to deal with the ABC’s before deferring care to a medical professional….
This would also sort out the insurance issue’s raised, as it would be the CC who would make the initial assessment on the passenger on not the called for professional!!