I'm an RN too. I work a blend of 11-7 and 7p-7a shifts in a NICU.
I know what you mean about the end of the shift being a nightmare time to find a minute to grab a snack; around 5-5:30 am we begin doing lab draws, ABGs (with the resulting ventilator changes, etc.), final feedings, weights (of babies on IV fluids) and linen changes, and also get all this stuff charted before 6:30 am. I'm telling you it's crazy at that time of the shift! The past few nights I have run into the breakroom and either grabbed a yogurt (I like a small amount of Greek yogurt mixed with chopped up peaches or nectarines) or a cereal bar (like Fiber One) and a cup of 1% milk right at 5:00 am before the craziness begins. I can scarf that size of a snack down in about 3 to 5 minutes if I have too. I have been able to succeed with this plan and if I get off work in time I find I'm not hungry before crawling into bed. If I eat earlier than 5:00 am I do get hungry by the time I get home around 8:00 am.
My saving grace is planning my meals ahead of time and packing them to take with me. I love to hear everyone's tips and suggestions. Shift work can be a real challenge to eating properly!