One of the tools physicians use to help people who take insulin keep their blood glucose in control is a sliding scale.
There are many reasons your health care provider may prescribe this type of insulin regimen for you but foremost it has to do with how much involvement you are able to have and want to have in figuring out your insulin needs.
Some people want to spend as little time and effort as possible with their insulin and are willing to follow a structured, time-bound meal plan. For these folks a fixed dose (taking the same amount of insulin at each meal regardless of their blood glucose level or the type or amount of food they are eating) is a good choice.
On the other end of the spectrum is matching insulin to carbohydrate. This requires a strong commitment to carb counting and following a mathematical algorithm at meals.
The sliding scale falls smack in the middle. No math to do, meal timing isn’t as important but carbohydrate content at meals does need to be standardized.
When people hear the term “sliding scale,” they might picture a balance scale with weights tumbling off one end. Now there is no physical object to slide; rather it is a chart that tells you how much insulin to give yourself at meals based on your blood glucose levels
The chart is divided into a series of columns. The column farthest to the left lists blood glucose ranges starting from below 70mg/dl to 400mg/dl or more, increasing in increments of anywhere from 20 mg to 50 mg/dl. The other columns correspond to breakfast, lunch and dinner, and, if necessary, bedtime.
The columns may have you take different amounts of insulin at different times of the day at the same blood glucose level. This may be because your sensitivity to insulin changes throughout the day or because your meals tend to be higher in fat at different times (high fat meals require more insulin)
To use the scale, you would check your blood glucose before meals. For example, at breakfast you would find the range on the scale in the farthest left hand column corresponding to the number on your meter and then scan to the right under the column headed “breakfast.” This is the amount of insulin to take before breakfast.
The amount of insulin moves (or slides) up and down in conjunction with the direction your glucose moves. Lower amounts of glucose equal less insulin; greater amounts more.
Sounds simple, but in the diabetes world nothing is ever as straightforward as it appears.
It turns out there are a few things you need to remember to get the best results from your scale. Sometimes in the rush to get everything else done in the short amount of time physicians have to meet with patients, the secrets of the scale are overlooked. This is why you should talk to your health care provider about the following issues before you start using your scale.
Take the sample sliding scale pictured below (remember, this is not one-size fits all, so do not use this sample scale without first talking to a doctor to get the right insulin doses for you). It indicates that if your blood glucose is below 70 mg/dl you are to treat it. But it doesn’t say what to do after you have fixed the low blood glucose. If you took this scale at face value, you would treat the hypoglycemia and then eat lunch without any additional insulin. Now say you decide to eat 60 grams of carbohydrate for lunch. If you are like many people, eating that amount of carbohydrate without any insulin will cause your blood glucose to spike.
Since there are different ways to handle this type of situation, you want to discuss this with your health care provider to find out which way might be best for you.
Unfortunately food is always part of the equation when we are talking about insulin. For a scale to work properly it helps to follow a consistent carbohydrate meal plan. The scale builds in a specific range of carbohydrate at each meal, often between 45 and 60 grams. If the amount of carbohydrate you eat at meals varies significantly day to day, a graph of your blood glucose numbers will resemble a five year’s old first attempt at Etch-a- Sketch®.
Despite the never ending barrage of educators telling you to never skip a meal, if you live in the real world there will be times when you don’t have time for a meal or don’t feel like eating. And what do you do if your blood glucose is 250mg/dl but you are not going to eat?
And there will be times you are very hungry between meals. Not all snacks have 15 grams of carbohydrate and some people need insulin to eat just five grams. These are two other areas to review with your physician before you walk away with your shiny new scale.
Again, there are different ways to handle these situations so there are no one size fits all answers, but this should get you thinking about some questions to ask at your next visit to your diabetes team.