48 hours to live is not much different from last eight years for me.
Now, if I was definitely going to die in 48 hours...
It's a deadline. I can do deadlines.
First, load up on an ungodly dose of glucose and caffeine and inject enough insulin to process that.
Second, notify any people that should be aware of the matter (which means not just at my work, but also any place where I am performing any sort of community function)
Third, start tying up any loose ends from my side. At least those I can manage to in those 48 hours. Those I can't, write instructions for others to do.
Finally, write a last will.