Chapter 9. Blood Glucose Monitoring
9.1 Introduction
Blood glucose monitoring allows people with diabetes to monitor their blood glucose levels and manage their condition accordingly.
Types of Diabetes
Type 1 diabetes usually develops in childhood or adolescence and used to be called juvenile-onset diabetes. It occurs when the beta cells of the pancreas are destroyed by the immune system and no longer produce insulin, or produce very little insulin. People with this form of diabetes need injections of insulin every day in order to control the levels of glucose in their blood. If they do not have access to insulin, they will die. There is no known way to prevent type 1 diabetes.
Type 2 diabetes used to be called non-insulin-dependent diabetes or adult-onset diabetes. It accounts for at least 90% of all cases of diabetes and can occur at any age. With type 2 diabetes, the body does not make enough insulin or does not respond well to the insulin it makes. Either or both of these characteristics — relative insulin deficiency and insulin resistance — may be present at the time diabetes is diagnosed.
Type 2 diabetes may remain undetected for many years, and the diagnosis is often made when a complication appears or a routine blood or urine glucose test is done. It is often, but not always, associated with overweight or obesity, which itself can cause insulin resistance and lead to high blood glucose levels. People with type 2 diabetes can often initially manage their condition through exercise and diet. However, over time most people will require oral drugs and or insulin.
Gestational diabetes is a form of diabetes that develops in women during pregnancy and disappears after delivery. Gestational diabetes affects about 4% of all pregnancies and increases the risk of developing type 2 diabetes.
Other specific types of diabetes also exist, and more information can be found at the Canadian Diabetes Association website.
Managing Diabetes
People with diabetes can manage their disease by monitoring their blood glucose levels. To measure blood glucose levels, blood is obtained through a skin puncture using a specified needle system, which is less painful and invasive than venipuncture. The ease of this skin puncture method makes it possible for patients to perform this procedure themselves.
In the hospital setting, a blood glucose machine (glucometer) is used to provide an accurate blood glucose level in less than a minute using a reagent strip with a drop of blood dropped or wicked onto a new, dry, specifically indicated portion of the reagent strip. These machines must be regularly calibrated according to agency policy, and each machine should be cleaned between use on different patients.
Ensure that you read and understand the manufacturer’s instructions and your agency policy for the blood glucose monitoring machines used in your clinical setting.
Learning Objectives
- State the abnormal and normal ranges for blood glucose levels in Canadian (SI) values
- Demonstrate the safe use of a glucometer machine
- Collect and organize appropriate equipment to perform a blood glucose test
- Describe the steps in performing a capillary blood glucose test
- Demonstrate dexterity and ability to accurately obtain a blood glucose sample
- Identify when a patient is hypoglycemic or hyperglycemic
- Discuss the management of hypoglycemia using a hypoglycemic protocol