Hi,
I think your Mom's situation may be more complicated and I would need to know more about her medical course to really give you an idea of what is going on. For your Mom to have become comatose after going low in her sugar, she would have had to have had a very serious event while low, like a series of seizures, a stroke or a heart attack, or stayed low for too long and thus suffered some brain damage. Many folks also do not become ventilator-dependent only from anemia; usually there is something else going on.
There is no direct connection between diabetes and a very low blood count unless you have autoimmune diseases that cause both(quite uncommon). People with diabetes can tend to have lower counts than those without, but not terribly lower. Many things can affect how your Mom's body handles her diabetes medication, and possibly many of them are not quite normal right now, including her kidney functions and liver functions, as well as medication interactions.
I am afraid I cannot offer you specific suggestions about this. I do suggest speaking perhaps with the hospital pharmacist and physicians taking care of your Mom to get an better idea of what interactions may be causing her situation to continue to be some complicated.
Good luck and take care.
I would like to see the Dr comments too. I wonder is that any connection with diabetes and low blood count? My gastro dr said I might need an iron transfusion (I refused the blood transfusion) each year. My mum has diabetes for more than 40 years. She need to top up the iron orally.