Wearing a continuous glucose monitor is a great way to see and understand how your blood sugar responds to various foods, activities, and insulin doses. Over the past several months of wearing the Dexcom, I've gained a greater awareness of high blood sugars, and more importantly, the most effective methods for maintaining blood glucose control.
One thing I discovered was that correcting high blood sugars nearly always led to one of two undesirable results: either a roller coaster of highs and lows for at least a few hours or a sustained high that took a few hours to bring down. In the first scenario I'd inevitably give a large correction bolus in an attempt to quickly bring down my blood sugar; which would lead to a low. Likely I'd over treat the low and end up higher than desired again. An alternative to a large correction bolus would be to deliver a smaller dose of insulin, which would bring my blood sugar down but only after a few hours; obviously not ideal when you're striving for very tight control. The CGMS allowed me to see these patterns in great detail.
Of course, there's the super bolus tactic which I've written about before; which involves giving a larger correction bolus and then suspending or lowering your basal rate for the next hour or two. It works well at times, but is certainly not a fool proof approach.
The more I thought about the various ways to deal with high blood sugars, the clearer the answer became: avoid having highs in the first place. Ah, easier said than done, I know.
Again, wearing a CGMS has allowed me to pinpoint the behaviors that allow me to avoid highs. Unfortunately, there's nothing radical to note, the best tactics are: 1) eat meals low in carbohydrates and 2) bolus early and accurately for everything you eat.
If a high blood sugar level will likely lead to either a half day roller coaster of highs and lows or a significant period of time spent out of range, it's worthwhile to plan better to avoid going high at all. With the CGMS, I could visually monitor how quickly my blood sugar began to drop after giving an insulin bolus. Prior to a meal, I can bolus 20-30 minutes before seeing an active drop in my blood sugar. Obviously bolusing right as I begin to eat will not keep my blood sugar steady, as many foods raise blood sugar faster than the insulin can lower it.
I can't count the number of times I've eaten a meal, watched my blood sugar rise, delivered a correction bolus and thought: if I'd only given the insulin earlier or increased the meal bolus, I would have avoided that high altogether.
Low carb meals are great for avoiding high blood sugar as they offer fewer variables you have to consider when calculating an insulin bolus. Whenever a meal contains multiple components that raise blood sugar, the likelihood of miscalculating the carbohydrate count is increased. A dinner of roasted chicken and vegetables is more simple to bolus for than, say, spaghetti and garlic bread.