A selection of resources
If atypical need to check it isn't something else
The NICE guidelines on this are actually very readable and to the point.
Some of the finest free to access resources out there
Helpfully short summary from east midlands emergency medicine gang.
Wonderfully summary highlighting many important points
Talk by @Damian_Roland at DFTB conference
Outcome measures was escalation of care, interestingly didn't particularly help with anything else.
Useful negative trial regarding the non-usefullness of nebulised hypertonic saline.