post-op and diabetes

this is hypothetical patient who is type 2 diabetic controlled by diet,
hospitalized for surgery, has nasogastric tube to suction, IV N/S 1000 mL, alternating with D5W 1000 mL

chemstrip shows 10-15 mmol/L so the doctor is notified
again one hour later it is 10-15 mmol/L so the resident is notified.

What would be reasonable treatment?
From my research so far, treatment could be either subcutaneous insulin (although there are problems with unpredictable absorption and erratic blood glucose), or insulin intravenous infusion that is more predictable and can be rapidly adjusted - either in separate infusion, or there is GIK mixture (but it can't be rapidly adjusted - the entire solution has to be changed if needed)
The resources that I've found so far are from 2005:
http://www.coa-aco.org/en/library/cl..._mellitus.html
and from 2003:
http://www.aafp.org/afp/20030101/93.html

Is there anything more recent that would be helpful?
What would be most useful for this type 2 diabetic, controlled by diet, who has a nasogastric tube, is NPO, post-op?
thanks