I am a current medical student, but I do have some tips for night shifts, - i worked in a healthcare facility where i would pull a 16 hour shift straight, and i would end up being up for 24-36 hours straight (from Sunday morning doing stuff, then pulling a 16 hour shift till 8 am on Monday, and then going straight to school till about 5 pm). So one thing i figured out, - it helps if you switch activities every hour or two. It tricks your brains and helps you stay focused. During slow times, when my patients did not need me, i went through school material, - if my brains were still fresh, i went through new material. If i was already tired, i would do practice questions. Frequent snacks and drinks help, - fruit, nuts, water, coffee, carbs. 2 am-5 am were always the hardest times, so i tried to schedule something that would require me to get up and frequently walk: for example, restock supply closet, or count medications, or something like that.
Hope this helps a bit. Cannot give you study tips yet, sorry.