Bypass Surgery

My Dad had a bypass yesterday.  Two questions - firstly he is getting insulin following the surgery - does this mean he may be a diabetic?  No history of this before now. Second question, his blood pressure is very low, is this normal following surgery of this nature?  

[Cleveland Clinic]

The insulin following surgery is to prevent hyperglycemia. In normal patients hyperglcemia at this level is usually called diabetes mellitus, but post surgery there is a cortisol surge which may cause hyeprglycemia in the absence of diabetes. The reason for tight control of blood sugars post surgery is to prevent blood stream infections, and to promote wound healing.  
I don't know what level of blood pressure you are referring to: 80/40 or 100/60 or 120/70. These are all ow for a normal person but the first number almost always means something is wrong, likely bleeding or infection. The second and third numbers can be considered normal, and in fact blood pressure post CABG can be maintained on the low side of normal to decrease myocardial contractility and oxygen demand.