The term Sliding Scale Insulin refers to a method that insulin can be delivered to diabetic patients. This treatment is almost universally done in a hospital setting. The term “sliding scale” means that the patient is given more or less insulin on a predetermined scale, depending upon his or her blood sugar levels.
Only short acting insulin (e.g., regular, lispro, aspart, glulisine) is typically given during this treatment method or protocol. Long acting insulin is not given using this method.
Very often the practice is used to treat diabetes patients experiencing hyperglycemia and possibly ketoacidosis. Although some institutions will also use it to fine tune or normalize blood glucose levels.
History and Controversy
The sliding scale insulin therapy or protocol has been widely used for over 70 years. Recently, there has been a growing controversy regarding its use as an insulin therapy method. Curiously, when and how you use the therapy is somewhat inconsistent. Let’s take a look at some of the different issues.
First, there seems to be more than a little confusion regarding how any given health care institutions develops its sliding scale for any given patient.
Generally, the amount of insulin any given patient will vary based on their medical condition and how they respond to insulin. Nonetheless, some institutions use a sliding scale that primarily is based on blood glucose levels. For example:
Other institutions factor in weight, as well. A calculation is done to determine the amount of units per kilogram of insulin you will receive according to a predetermined “sliding scale.” For example, one health care organization we reviewed has charts based on the following:
- Low dose Regimes
- Medium Dose Regimes
- High Dose Regimes
- Very High Dose Regimes
The chart goes in great detail about how much insulin to be given based on weight and glucose levels.
Still other hospitals develop custom sliding scale charts that look at the blood glucose levels and the amount of insulin you normally take during the day.
Is this confusing? Yes!!
Second, another controversy is that sliding scale delivery completely ignores the way your body uses insulin.
Meaning, your body needs insulin at certain times during the day based on a variety of factors such as when and how much you eat, etc. Thus, opponents suggest that it is not the most effective way to normalize or control blood glucose levels.
Third, another criticism is that sliding scale insulin therapy is reactive, not proactive.
Determining insulin dosage is done as a reaction to what your current blood glucose levels are. Proactive methods such as diet, exercise and consistent insulin dosing therapy are not really considered.
So who is right? What approach is best? What do the scientists say? Well, it depends. (Of course, you knew this already!).
The American Diabetes Association recently published an article that detailed the scientific controversy. Essentially, the author concludes that there are not enough consistent studies to definitively prove or disprove the use of the protocol or therapy. There may still be cases where the method of insulin delivery is needed. You can read the discussion here.
So is the sliding scale still viable? Dr. Anuj Bhargava wrote an interesting article in the Insulin Journal. He concluded that the therapy’s controversy stems from its misuse. The default method of many hospitals is to stop all other diabetes treatments (e.g., oral medications, other insulin injections, etc.) and strictly adhere to a sliding scale insulin protocol. He asserts that this is a huge mistake.
Instead, he concluded that the therapy should be used in conjunction with a patient’s existing treatments, e.g., other medication sand longer acting insulin injections. Because it is not a replacement therapy, he prefers to call it Supplemental Insulin Scale or Correction Scale.
Under his approach, the patient continues to proactively treat their diabetes (oral medications and longer acting insulin) AND gets the extra insulin they need during their hospitalization (sliding scale treatment).
Newer research suggests that there has been a move away from using the sliding scale protocol in all hospitalization case. If the patient is not in critical conditions, other insulin protocols or treatments are recommended. However, clearly there is still a time and a place for the therapy and further research is needed.
If you are assigned a sliding scale insulin therapy, make sure you keep very clear and detailed records. Check with your doctor or health care team to determine the best approach and necessary information to collect.
Also, if you have doubts or concerns about the therapy, voice these concerns to your doctor. Maybe there is a more appropriate treatment for your individual situation.
By Erich Schultz – Last Reviewed April 2011.