Hi Bebefrida. Best wishes with your treatments.
I think it's always best to start a new thread if you are not answering someone's concerns directly. I am thinking the forum "Currently In Treatment", would have been fitting.
But to answer your question, each case is unique, so there could be a reason why they need 24 hours to analyze your blood work.
In my case, going into chemo day, they drew my blood immediately, and then immediately started IV hydration. The hydration was to help protect my kidneys from the Cisplatin.
My results would come back after about 2 hours, and if acceptable, all the other drugs and then chemo were started.
I think the main thing they needed from the blood work, was the indicator that showed kidney function.
So I am just guessing, but it could be a few things as to why they wait until the next day in your case.
Do they have a lab that can turn around the blood work in 2 hours? Do they have enough chemo stations to occupy one for 2 hours of hydration, if it turns out that you are not ready to get the chemo that day?
Maybe, there is some unique condition, that didn't apply in my treatment.
Best advice, ask your Nurse or Oncologist why you have to wait until the next day, so you know the exact reason for your situation.
All the best!