Hello. It has been a while since you posted. I hope all well with your husband.
I am non-insulin dependent diabetic after having a Whipple in 2002. When diagnosed, I found lots of valuable information on the American Diabetics Association website.
Since they removed your husband's pancreas, he is I think considered type 1 diabetic. I have known several Type 1 diabetics in my lifetime, and it was a challenge for them to control blood sugar. With your husband, there is the added challenge of possible mal-absorption of nutrition due to no natural digestive enzymes. It is a very difficult situation your husband faces. He may consume a serving of carbs, but not absorb it and therefore have too much insulin in his system. The low blood sugars are unpleasant, and very scary.
In my experience, not all carbs are the same. Although they may have the same carb count per serving, some foods cause my blood sugar to go sky high. For example, I no longer eat baked potatoes, and I severely limit consumption of rice. However, I can eat pasta without ill affects. It just takes time to find what works for you.
Following the Whipple, the doctors had me on a diet regimen of eating several small meals throughout the day. To get my blood sugar under control, it was necessary for me to change back to eating three meals daily, with a snack before bed. This worked great for me once I learned which carbs I tolerate, and how much digestive enzymes I needed to make sure I digested the food I consumed. I am able to maintain my weight now with 1800-2000 calories daily. Before being diagnosed with diabetes I was consuming 3000 calories or more a day, and still losing weight.
You guys are facing a big challenge and I wish you the best of luck in finding the path back to good quality of life.