Why do some doctors order ancillary glucose every 6 hours? even if not npo?

Unsure of meaning: If someone is on Insulin or other drugs that are meant to lower blood sugar, or in people who have "reactive hypoglycemia" where blood sugar comes down too low on its own, having glucose (or better - complex starches) on a periodic basis to avoid very low sugars - hypoglycemia - may be necessary. Hypoglycemia may only cause dizziness or lightheadedness, but can also cause seizures and fainting.

Question not clear: If diabetes is not well controlled your doctor may order accuchecks more than twice a day, to adjust your medications for better control.

Don't know : Random blood sugars every 6 hours independent of meal timing makes no sense, especially for someone with diabetes.