This question is for long haul flights from Australia to the US. I need to bring 4 self-injectables (1 for each week I'm in the US/Canada) which need to be refrigerated. Can't carry 'sharps' in carry-on luggage to be kept cold in plane fridge, but if they're put into checked luggage, they won't stay cold for 20 hours, given travel/wait times pre and post flight. Anyone done this before without being turned back at Customs/Border Protection in LA?