Again, I'm very sorry to hear about this situation. It is one of the hardest things in my job to have to quantify what a person's life is worth in a wrongful death situation.
Generally, the valuation of a death often revolves around how much income a person brings in, how much longer they had to live based on the average life span in the United States, the loss of the persons services at home, and the simple loss of the person's company. In this case, it sounds as if your father was retired. He was also already past the average life expectancy (78.2 years).
As that is the case, there are no real economic damages that we can use to quantify what you should demand from the hospital. All the damages turn on what are referred to as "soft damages", i.e., the value of the loss of your father as a companion and the pain and suffering he endured as a result of the hospital's failure.
Given the fact that your father was not properly cared for because of simply hospital negligence and was in pain for the last 24 hours of his life, this increases the value of your potential claim. I recommend asking for $100,000.00. This is large enough to be a meaningful punishment to the hospital for its failures and to hopefully provide you with some peace of mind.
If they do not like that offer, it would probably be a good idea to get a personal injury
attorney to represent you in the demand.
Please let me know if you have further questions.