Canadian Diabetes Care Guide
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Monitoring blood glucose

A speedometer on your car helps you control your speed... monitoring helps you control your blood glucose.

Blood glucose readings:

  • Let you know what your blood glucose level is at the moment you take it.
  • Help you understand the relationship between the food you eat, physical activity, medications and your glucose level.

Home glucose monitoring is done with a glucose meter, a small, portable machine that measures the amount of blood glucose in your blood. Each meter comes with a lancing device specially designed to draw a small sample of blood from your fingertip as painlessly as possible. Once you have a sample of blood, it is placed on a test strip, which is then read by the meter.

There are many models of blood glucose monitors available in Canada. Each model offers its own combination of features. It is helpful to discuss which meter is best for you with your diabetes educator or pharmacist.

Meters are usually obtained at retail pharmacies or diabetes clinics. If you are going to purchase a meter for the first time, it is best to receive training from the pharmacist or diabetes educator. Call ahead and schedule an appointment to learn the best technique for accurate results.

Testing Tips:

  • Wash your hands with warm water and soap, and dry them well. Avoid alcohol, as it can dry your skin.
  • Set your lancing device at a comfortable depth. Try a different lancing device if the one you are using is not comfortable.
  • Look for lancets that are thinner and shorter, and ensure they will fit in your lancing device.
  • Replace the lancet each time you use it.
  • When testing, use the sides of your fingertips and rotate amongst your fingers.
  • Discard your lancet and strips in a sharps-rated container. Check with your pharmacy for options available in your community.
  • Store your strips away from sunlight and moisture.

Track Your Results

When you monitor your blood glucose levels, track them in a diary or blood glucose log. Talk with your diabetes team about interpreting your results. When looking at glucose readings, it is patterns and trends that are important – not an occasional reading that is out of the ordinary. (download “Once-Daily Testing Pattern” chart).

With the information from your blood glucose patterns, adjustments to your food, activity or medications can be made to make sure you are achieving as healthy glucose control as possible.

Discuss your individual goals with your diabetes team. According to the Canadian Diebetes Association 2003 Clinical Practice Guidelines for the prevention and management of Diebetes Canada, the target range for most individuals is:

 
Before Meals
2Hrs After a Meal (from the time you started your meal)
Normal Range of Glucose (Achieve these levels if you can do it safely)
4-6 mmol/L
5-8 mmol/L
TARGET
4-7 mmol/L
5-10 mmol/L

It is helpful if you test your blood glucose at a variety of times during the day, both pre and post meals. It is quite possible for your morning, pre-breakfast glucose to be in the target range, and your 2 hour post lunch reading to be high. Patterned glucose readings, such as several pre-supper readings in a week, provide a more complete picture than one individual reading.

More frequent testing may be necessary if the blood glucose is not well controlled, if hypoglycemia (low blood glucose) occurs, or in unusual situations such as travel, illness or exercise.

Speak with your educator about which pattern of monitoring you should follow. Download a sample chart of Once-a-Day Patterned Glucose Readings.

Verify your meter’s accuracy once a year. Do a glucose reading from your finger at the same time a lab sample is drawn, then have the meter result recorded directly on the lab requisition…when the results from the lab test are reported, the difference should be no more than 20%.

What affects blood glucose levels?

A RISE in Blood Glucose levels can be caused by:

An increase in the amount and/or type of carbohydrates you eat. Most foods, except fats and meats, contain carbohydrates. When you eat foods that have a high concentration of carbohydrates per serving, or you have an increased amount of your usual foods, your blood glucose will rise.

Glucose released by the liver overnight
Your body requires glucose 24 hours a day, seven days a week. Your liver stores glucose and releases it during the night. With type 2 diabetes, your liver can sometimes release too much glucose. This explains why your glucose may be higher in the morning than before you went to bed – even when you’ve had nothing to eat.

Illness
An illness can pose special problems for people who have diabetes. Illness is a stress on your body that can cause your blood glucose levels to go up. Even a minor illness such as a cold, flu or infection can raise your blood glucose level.

Stress
Emotional stress caused by excitement, anger, worry and fear can cause an increase in blood glucose.

Not enough medication
When you have less medication than normal (a missed dose for example) or the medication you are taking is not effective enough, blood glucose levels will rise.

You may have experienced some of the signs of high blood glucose since you were diagnosed, these include: thirst, frequent urination, blurry vision, dry or itchy skin, hunger, feeling tired, unexplained weight loss, cuts that won’t heal, numbness or tingling in hands and feet.

IMPORTANT - Sometimes there are no symptoms when your blood glucose is high. The only way you can be sure what your blood glucose is, is to check it.

A DROP in Blood Glucose levels can be caused by:

Type and amount of food
Delaying or skipping a meal, or having a meal with less carbohydrate than you normally have.

More activity than usual
If you increase your level of activity, your blood glucose levels can drop. Whenever you start a new activity, monitor more frequently to watch for glucose changes.

More medication than usual
When you have more medication than normal (an extra dose for example) blood glucose levels can drop.

The signs of low blood glucose (hypoglycemia) include shaking, confusion, extreme hunger, sweating, fatigue, moods swings, experiencing a rapid heart beat or even passing out.

If your blood glucose is low - less than 4mmol/L:

  • Check your glucose. (If you can’t test and you have symptoms, go ahead and treat it).
  • Take 15 g of ‘fast acting’ carbohydrate right away, (15 g glucose tablets or 3 tsp. sugar).
  • Wait 15 minutes and recheck blood glucose. You should be feeling better.
  • If you are not feeling better, or your glucose level is less than 4 mmol/L, repeat 15 g of ‘fast acting’ carbohydrate.
  • Glucose tablets are the preferred method of treating lows. Some quick sugar remedies are: 1/2 cup orange or apple juice 1 small box of raisins 2 teaspoons of honey or sugar 3 dextrosols or 4 hard candies

If your next meal is more than 1 hour away, eat a snack of a starch and protein (cheese and 6 crackers, half of a peanut butter or meat sandwich).

If the blood glucose is severely low - less than 2.8 mmol/L and one is conscious:

  • Take 20 g of carbohydrate preferably as glucose tablets
  • Wait 15 minutes and recheck blood glucose
  • If you are not feeling better, or your glucose level is less than 4 mmol/L repeat 15 g of fasting acting carbohydrate

Some people who take insulin may need a Glucagon Kit available for emergencies. If your blood glucose drops so low that you become unconscious or can’t swallow, an injection of Glucagon may be necessary. If you take insulin or have ever passed out due to low blood glucose ask your doctor about a prescription. If you are already using Glucagon, set time aside to review the procedure with your friends, family and co-workers.

If you are taking medication that increases your insulin levels, or if you take insulin injections, you are at risk for low blood glucose.