You might want to have a look at the 3c forum - type 3c diabetes is where the pancreas isn't producing any insulin due to damage from pancreatitis and, I think, over internally caused pancreatic damage, so I think it is relevant when you have had a pancreatectomy:
http://www.diabetes.co.uk/forum/category/type-3c-pancreatic-diabetes.73/
I think 3c a bit different from type 1 in that, as well as no insulin, you are also losing all your other pancreatic functions (not sure what they are, but I'm sure it does something else, hormones etc, assuming the whippe procedure removed all or most of the pancreas, and you have to take into account the othe medications your husband might be on. But the basics on taking insulin etc are the same whatever the reason you are insulin dependent.
Is humalin 1 a mixed insulin - so he's on a fixed dose? If he hasn't got much appetite it would definitely be worth speaking to the DSN to get some advice on titrating the insulin dose down to try and avoid the night time hypos.