Mike I think you are barking up the wrong tree. In the non-entrapped patient just forget on-scene cannulation regardless of size. Reduce the on scene time to less than ten minutes by doing less. As one of those receiving trauma patients in hospital I would prefer to get the patient sooner without cannula but simply well oxygenated by bag/valve/mask if necessary. In Hospital the priorities are ABC - Airway, Breathing, Circulation. Pre-Hospital I would suggest that the priorites should be ABDFF - Airway - Breathing - Drive "Flipping" Fast Andrew Hobart FRCS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%