Your Insulin Adjustment Workbook Yes, You Can Do It!

Transcription

1 S T AY I N G O N T A R G E T TARGET THERAPY Staying on Target TM Your Insulin Adjustment Workbook Yes, You Can Do It!

2 YES, YOU CAN DO IT! Your How-To Guide for Adjusting Basal and Bolus Insulin This workbook will help you learn new skills so that you can you live a healthier life with your diabetes. What is Basal-Bolus? introduces flexible insulin therapy, (also called intensive therapy) as a way to correct your blood glucose levels. Terms to Learn First gives you the definitions that you will need. Making Bolus Insulin Changes, outlines how to make changes to rapid and short acting insulin doses. Putting it All Together gives you a plan to get started. Adjusting for Basal Insulin, explains changing long acting insulin doses. Trouble-Shooting, tells what to do when you are having a hard time. Problem-Solving and Exercises gives you a chance to practice what you learned. Use this guide as you work with your diabetes health care team to help you avoid the complications of diabetes. BD provides this workbook for informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified healthcare provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read in this workbook

3 INTERACTIVE TABLE OF CONTENTS To go directly to the topic of interest, click on the link below. WHAT IS BASAL-BOLUS?...1 Managing Your Blood Glucose...2 Practicing Flexible / Intensive Therapy...2 Responsibilities / Rewards of Basal-Bolus...2 Normal Insulin Delivery...3 TERMS TO LEARN FIRST...4 Blood Glucose Goals...5 Target Glucose...5 Algorithm...5 Basal Insulin...6 Bolus Insulin...6 Insulin Adjustment and Pattern Management...7 Insulin Sensitivity Factor (ISF) and Correction...7 Peak Action...8 MAKING BOLUS INSULIN CHANGES...9 Understanding How Insulin Works...10 Blood Glucose Monitoring: When to Test...12 Making Changes Using Pattern Management...13 Correcting for Blood Glucose That is Out of Range...17 Correction Method I...18 Correction Method II...18 Correction Method III...19 Calculating Your Insulin Sensitivity Factor (ISF)...19 Insulin/Blood Glucose Formula...19 Rule of Rule of Correcting for Known Changes in Meals or Exercise...25 Correcting for a Change in Meals...25 Calculating Your Carb:Insulin Ratio...25 Method I...26 Method II...26 Correcting for a Known Change in Exercise...29 PUTTING IT ALL TOGETHER...30 Getting Started: A Five-Step Plan...31 Practice Problems...31 ADJUSTING THE BASAL DOSE...34 Testing the Nighttime Basal...35 Testing the Daytime Basal...37 Option I...37 Option II...38 Option III...38 TROUBLESHOOTING...39 PROBLEM SOLVING AND EXERCISES...44 SEE YOU REALLY CAN DO IT!...49

4 WHAT IS BASAL-BOLUS? 1

5 WHAT IS BASAL-BOLUS? When you have diabetes, it is important to avoid high and low blood glucose (sugar). This section reviews how outof-control blood glucose can lead to diabetes complications. It also introduces flexible/intensive therapy with basal-bolus insulin adjustment 1 as a way to help keep you healthy. Managing Your Blood Glucose Keeping in control means that your blood glucose is always in a range that is not too high or too low. Controlling blood glucose helps you stop or delay the risk of developing eye, kidney, nerve, foot and heart disease caused by blood glucose that is too high for a long period of time. It can be hard to stay in control with one, two, or even three injections of insulin a day. You can still have many times when the insulin does not match your food or exercise, so your blood glucose gets too high or too low. Practicing Flexible / Intensive Therapy Research shows that flexible (also called intensive) insulin therapy can work to control blood glucose levels in most people. With this therapy you: 1. Take four or more insulin injections a day, adjusting your insulin doses as needed to keep your blood glucose within your goal range OR 2. Use an insulin pump. The goal is to keep your blood glucose close to normal by taking insulin to match the quantity of food you eat and also meet your body s needs at other times. The insulin that works between meals and through the night is called basal. The insulin that works to match food or lower high blood glucose is called bolus. Basal-bolus is a term used by health care professionals to describe flexible therapy. Responsibilities / Rewards of Basal-Bolus Before starting flexible (basal-bolus) therapy, you should think about its pros and cons. Pros You will have more freedom and other benefits, such as: Ability to eat when and how much you want Freedom to skip a meal Better diabetes control Feeling of greater well-being Reduced risk of complications Cons You will have more work, including: Checking blood glucose four or more times a day, and sometimes during the night Learning and practicing carbohydrate (carb) counting 1 All glucose values used in this workbook are plasma values. If you use a blood glucose meter that reads whole blood values, you should decrease them by about 10%. 2

6 Deciding on your insulin dose according to the amount of carb you expect to eat and the exercise or activity you plan Although some people can have frequent or severe hypoglycemia (low blood glucose) with this therapy, most people have less because there is a better match between their insulin and food. You can adjust flexible therapy for your lifestyle, eating and sleeping schedules and physical activity. You will learn to match your insulin to your food, exercise, and adjust for high or low blood glucose when it happens. Normal Insulin Delivery A diabetes-free pancreas releases a small amount of insulin throughout the day and night. This insulin is described as basal and is steadily discharged from the pancreas so that there is always some available. At night and between meals, basal insulin works with a small amount of glucose made by the liver that is also being constantly released. After eating a meal or snack with carb in it, two things happen: 1. Blood glucose rises. 2. The pancreas releases an extra burst of insulin that in turn helps to deliver blood glucose into the body s cells, where it is used for energy. This insulin is released as a squirt or a pulse that is called a bolus. In someone without diabetes, a bolus of insulin keeps blood glucose levels in range after meals. Figure 1 shows normal insulin delivery in a person without diabetes. The top portion shows the blood glucose curves during a day in which someone eats three meals. The bottom portion shows the blood insulin levels for the same three meals. In basal-bolus therapy, the insulin doses and times are designed to match normal insulin delivery as closely as possible. Blood Glucose Blood Insulin Figure 1 Normal Insulin Delivery in People without Diabetes High Normal Low Basal 3 AM 6 AM Bolus 9 AM Noon 3 PM 6 PM 9 PM Midnight Midnight If you have type 1 diabetes, your pancreas cannot make insulin. To use flexible therapy with basal-bolus insulin, you will decide how much insulin to take to keep blood glucose within your goal range. 3

7 TERMS TO LEARN FIRST 4

8 TERMS TO LEARN FIRST The goal of flexible therapy is to imitate the way a normal pancreas works. In someone who does not have diabetes, insulin automatically works at the right times, matching meals, activity or stress. When you have diabetes and use flexible therapy, you have to figure out and deliver the correct dose of bolus insulin yourself. Your Diabetes Team will guide you along the way. Your Diabetes Team may include your doctor, certified diabetes educators such as a diabetes nurse educator and a registered dietitian. Some teams also include an exercise physiologist, social worker and pharmacist. This section teaches you words you need to know before you begin. Blood Glucose Goals The range your blood glucose should fall into most of the time. The American Diabetes Association (ADA) recommends the following blood glucose goals of mg/dl before meals and less than 180 about 2 hours after a meal. Your Diabetes Team will help you set your goals, for your blood glucose. Target Glucose A single number that falls within your blood glucose goals. The target glucose is used to adjust your insulin dose. Algorithm A formula that helps you determine the amount of insulin that you take before eating based on your current blood glucose level. Some people may have a different algorithm for each meal. Think of it as following a recipe. A sample algorithm looks like the chart below. This is only a sample. You should not use this table for treatment. SAMPLE ALGORITHM Pre-Breakfast Algorithm For Rapid Or Short Acting Insulin If your Blood Glucose is: 0-100: 2 units units units units units Over 300 Your Rapid-Acting Insulin Dose should be: 12 units STEPS FOR USING A ALGORITHM 1. Test your blood glucose. 2. Find your reading in the blood glucose column. 3. Check the rapid-acting insulin dose column to see how many units to take. For example, according to the algorithm if your blood glucose level were 184 mg/dl, you would need to take 4 units of rapid or short acting insulin before breakfast. 5

9 NOTE: For an algorithm to work you need to eat the same amount of food and carbohydrate every day. (If you always have a sandwich with 2 slices of bread, a piece of fruit, a glass of milk and a small bag of chips for lunch, this method will be fine.) If you eat a big salad one day and a plate of spaghetti the next, these foods have different effects on your blood glucose and you would need different doses of insulin, so this is not the best way for you to decide how much insulin to take before meals. Basal Insulin Works steadily day and night to keep your blood glucose within your goal levels. Taken as an injection, basal insulin is long acting and works around the clock. Taken via insulin pump, a very small amount of basal insulin is released constantly at fractions of a unit per minute. The goal is to match the amount of insulin with the low level of glucose produced by your liver. This helps your blood glucose levels remain stable day and night - even if you don t eat anything. Types of basal insulin include: Long-acting insulin such as insulin glargine (Lantus ) is often used for basal insulin because they last a long time and have no peak action. Ultralente - occasionally used as basal insulin, does have some peak action. (See Peak Action.) Short or rapid-acting insulin (see below) given by an insulin pump tiny amounts of rapid acting insulin are delivered throughout the day and night. This is the best example of basal insulin and may be closest to imitating the way the pancreas normally works. Another advantage is that basal rates on a pump can be changed to meet your needs at different time periods of the day and night. Bolus Insulin Taken before you eat and to correct for a high blood glucose, it is released in a squirt or pulse. This allows the insulin to provide a rapid burst of action. Bolus insulin acts as the extra insulin that is released by a normal pancreas to help your body use the glucose from a meal or snack. The extra insulin will bring your blood glucose levels down before they climb too high. Types of Rapid-acting insulin used for bolus insulin are: Insulin Lispro (Humalog ), Insulin Aspart (Novolog ), Insulin glulisine (Apidra ) or Regular insulin, which is referred to as a short-acting insulin. 6

10 Insulin Adjustment and Pattern Management Adjusting insulin doses based on a pattern of blood glucose readings over three days or more is called Pattern Management, or Pattern Control. If your blood glucose is too high or too low at certain times of the day or night, an adjustment to your insulin dose may be needed. In this case it is helpful to look for patterns in your blood glucose readings over three days or more. For example, take a look at Jean s blood glucose readings before dinner for the past three days: JEAN S THREE-DAY BLOOD GLUCOSE RECORD (Goal 90 mg/dl-130 mg/dl) Breakfast Lunch Dinner Bedtime 98 mg/dl 129 mg/dl 250 mg/dl 150 mg/dl 89 mg/dl 105 mg/dl 225 mg/dl 111 mg/dl 102 mg/dl 88 mg/dl 240 mg/dl 138 mg/dl You can see that her dinner numbers are all too high. The problem may be related to how much carbohydrate (carb) she ate at lunch, snacking, schedule or basal insulin. However, it is most likely that her food at lunch did not match her pre-lunch bolus. She ate too much carb for her insulin bolus dose. For more information on Pattern Control or Pattern Management, see the BD Publication: Pattern Control. Insulin Sensitivity Factor (ISF) and Correction ISF is the amount that one unit of rapid- or short-acting insulin will lower your blood glucose reading. It is used to calculate your correction or supplemental dose. Correction dose is the amount of insulin you need to correct a high blood glucose level and bring it into the range your blood glucose should fall into most of the time. Once you know your ISF, you can give yourself the right dose of insulin to keep you within your blood glucose goals. The ISF is different for different people and your Diabetes Team will help determine it for you. For instance, if your blood glucose at lunch is 200 mg/dl and your goal is mg/dl, you will learn to take a correction dose, an extra amount of rapid- or short-acting insulin to bring your high blood glucose down to the range your blood glucose should be in most of the time. Correction is usually required before a meal, so you will need to add or subtract this dose of insulin to the amount of insulin needed for your carbohydrate intake. The correction dose is extra insulin if your blood glucose is too high or a lower insulin dose if your blood glucose is to low. 7

11 EXAMPLE: Calculating Laurie s Correction Dose Laurie s ISF is 1 unit of rapid or short acting insulin for every 50 mg/dl of blood glucose. Her target pre-meal blood glucose is 100 mg/dl, but her pre-dinner blood glucose reading is 250 mg/dl. She is 150 mg/dl over her target level. Current blood glucose target blood glucose = amount of glucose over target [250 mg/dl 100 mg/dl = 150 mg/dl] Using Laurie s ISF, she would divide 150 mg/dl by 50 to find that she would need to add an extra 3 units of rapid or short acting insulin to her meal-time dose to correct the blood glucose to 100 mg/dl. Amount of glucose over target ISF [ 150 = 3 ] 50 = correction dose If Laurie s pre-dinner blood glucose was 75, she would reduce her insulin dose in the same manner as outlined above. Her target pre-meal blood glucose is 100 mg/dl, but her pre-dinner blood glucose reading is 75 mg/dl. She is 25 mg/dl below her target level. Current blood glucose target blood glucose = amount of glucose over target [75 mg/dl 100 mg/dl = -25 mg/dl] Using Laurie s ISF, she would divide 25 mg/dl by 50 to find that she would need to subtract 0.5 units of rapid or short acting insulin to her meal-time dose to correct the blood glucose to 100 mg/dl. Amount of glucose = correction dose over target ISF [ -25 = -0.5 units ] 50 Peak Action The time when insulin is working the hardest to bring blood glucose down. It is essential to know when your insulin peaks so that you can prepare for possible low glucose levels at these peak times. Types of insulin with peak action times are: Name of Type of Peak Action Insulin Insulin Humalog, Rapid 30 min. to Novolog, 1 1/2 hours Apidra Lantus Long No peak action *Regular Short 2 to 4 hours *UltraLente Long 8 to 30 hours *NPH Intermediate 4 to 12 hours *Lente Intermediate 7 to 15 hours *Not commonly used in Flexible Insulin Therapy 8

12 MAKING BOLUS INSULIN CHANGES 9

13 MAKING BOLUS INSULIN CHANGES Your first step in learning how to make these adjustments should be to consult with your Diabetes Team. This section will give you the tools you need to adjust your bolus insulin effectively using flexible insulin therapy. Understanding How Insulin Works Different types of insulin work at different speeds. Their action can be described as basal (steady and longacting), bolus (rapid burst of action) or somewhere in between. They also act differently in how fast they start working, when they are at their peak and the length of time they last. It is important to understand these differences in order to make the best decisions possible when adjusting your insulin dose. By knowing which insulin peaks and is active you will know which insulin to change if you are having hypoglycemia (low blood sugar) or hyperglycemia (high blood sugar). View the chart(s) and graph(s) below to help you understand the actions of many different types of insulin including Humalog, Novolog, Regular, NPH, Ultralente, Lantus, etc. INSULIN ACTION CURVES Insulin Action Type of Insulin Onset of Action Peak Action Duration RAPID ACTING (Used for bolus insulin taken before eating and to correct for a high blood sugar) Insulin lispro (Humalog ), Insulin aspart (Novolog ), Insulin glulisine (Apidra ) 15 minutes 1/2 to 1-1/2 hours 3 to 5 hours SHORT ACTING Regular 1/2 hour 2 to 4 hours 6 to 8 hours Blood Insulin Level 6AM 9AM Noon 3PM 6PM 9PM MidN 3AM 6AM 9AM Insulin Commonly Used in Flexible Insulin Therapy for a bolus dose: Rapid-acting insulin is the most common insulin used, but shortacting insulin is also used for this purpose. 10

14 Insulin Action Type of Insulin Onset of Action Peak Action Duration LONG ACTING (Use for basal insulin taken in injection or in a pump to act through day and night to keep blood glucose levels stable) Ultralente Lantus Approx. 4 to 8 hours 2 to 4 hours 12 to 18 hours No peak, stable Approx. 24 to 28 hours 24 hours Blood Insulin Level Blood Insulin Level 6AM 9AM Noon 3PM 6PM 9PM MidN 3AM 6AM 9AM The most common insulin used for basal doses is Lantus, although Ultralente can also be used. Insulin Action Type of Insulin Onset of Action Peak Action Duration INTERMEDIATE NPH, Lente 1 to 3 hours 6 to 12 hours 18 to 24 hours 6AM 9AM Noon 3PM 6PM 9PM MidN 3AM 6AM 9AM NPH insulin may be used as a partial basal dose in the evening. This is most commonly used with shortacting (regular) insulin as a bolus dose. Fill in the chart/graph below to show the action of the types of insulin you are taking now: My Bolus insulin: My Basal insulin: Starts to work at: Peaks (Works hardest from) Lasts until: Starts to work at: Peaks (Works hardest from) Lasts until: _ Graph your insulin curves below: 7AM Noon 6PM 12MN 7AM 11

15 Blood Glucose Monitoring: When to Test Checking your blood glucose levels is important. You need the information to 1) Make insulin changes, and 2) See if you made the correct adjustments. Many people using flexible insulin therapy check their blood glucose before each meal and at bedtime. Your Diabetes Team may also ask you to check your blood glucose two hours after a meal. (This reading will show how well the mealtime insulin dose is working.) In addition, to make sure that you are not having hypoglycemia at night, it is sometimes important to check blood glucose at 3AM. The 3 AM blood glucose, although inconvenient, is important because it can help guide the decision to change your nighttime basal insulin. It is common for blood glucose to drop before 3 AM and then to rise by morning. Figure 3 shows the effects of different types of insulin on your blood glucose at different times of day. Figure 3 Effects of Previous Insulin Dose on Blood Glucose Readings Tested at Mealtimes and Bedtime Insulin Dose Breakfast Lispro Lunch Lispro Supper Lispro Bedtime Lantus Blood Glucose Breakfast BGM Lunch BGM Supper BGM Bedtime BGM HINT: If your blood glucose meter can do mealtime averaging, this can help you find the times of day that your blood glucose levels are usually too high or low. Along with your careful reflections about your carbohydrate intake, stress and activity levels, this may also guide your insulin adjustments. 12

16 Making Changes Using Pattern Management You can learn to adjust your insulin dose by looking at your pre-meal blood glucose levels over three or more days to see if you notice any special pattern. In the following example and throughout the workbook, assume that the blood glucose goals recommended by the American Diabetes Association are in use (pre-meal plasma values of mg/dl, blood glucose 2 hours after meals less than 180 mg/dl.) 2 and a target of 100 mg/dl. How to Evaluate Your Blood Glucose Record: Record your blood glucose levels in column format (as below) to more easily identify a pattern. Many of the data management software programs will do this for you automatically when you download the data. Look at the readings by group according to the time of day. Select the blood glucose readings by group that are out of your goal range. Day # Breakfast Lunch Dinner Bedtime 3 AM Day 1 Day 2 Day 3 Three-day Blood Glucose Record: Pre-meal Goals mg/dl Post-meal Goals < 180 mg/dl Pre Post Pre Post Pre Post Guidelines for Pattern Management Any time you see a consistent pattern of either high or low blood glucose levels over a period of three days, you could adjust your insulin by: Increasing the appropriate insulin or decrease the food eaten if the blood glucose levels are too high. Decreasing the appropriate insulin or increasing the food eaten if the blood glucose levels are too low. Most of the time the appropriate meal to change or insulin to adjust is the rapid or short-acting insulin taken the meal before the out of goal values appeared. 2 American Diabetes Association, Standards of Medical Care for Patients With Diabetes Mellitus. American Diabetes Association: Clinical Practice Recommendations, Diabetes Care. 27:Supl:10,

17 Q&A PRACTICE PROBLEMS Q What is the Pattern in Jane s Three-day Blood Glucose Record? Pre-meal goals mg/dl Post-meal goals < 180 mg/dl Day # Breakfast Lunch Dinner Bedtime 3 AM Pre Post Pre Post Pre Post 1 Mon Tues Wed Average A Jane s pre-breakfast, pre-lunch and pre-supper readings are in goal blood glucose range, but her bedtime readings are all high and out of range. Q Does Jane Need an Insulin Adjustment? A Maybe! But first she should think about whether she had eaten too much carb at dinner. Over the next few days, she should decrease her portion sizes of food at dinner she is eating (which will decrease the amount of carb). If there is no improvement in her blood glucose readings, Jane should look for other possible causes and solutions. Q Could Jane s dinner insulin (Humalog ) be the reason that her bedtime glucose is out of range? A If Jane suspects her dinner insulin needs to be adjusted, she could try increasing it by unit. Over the next three to five days she would need to observe whether her bedtime blood glucose readings are improved. NOTE: It is very important to consider all possible causes for an out-of-goal blood glucose reading before you adjust your insulin dose. The nice thing about pattern management is that you can make a small change every few days with great safety! 14

18 Q What is Different About Tom s Three-day Blood Glucose Pattern? Pre-meal goals mg/dl Post-meal goals < 180 mg/dl Day # Breakfast Lunch Dinner Bedtime 3 AM Pre Post Pre Post Pre Post 1 Mon Tues Wed Average A In this record, the breakfast, lunch and dinner values are in the goal range. However, the bedtime values are not only too high on average, but also too variable. Tom needs to look for and understand what caused the low value of 73 at bedtime on Tuesday. Any time you see a consistent pattern of either high or low blood glucose levels over a period of three days, you could adjust your insulin as follows. Either increase the appropriate insulin if your blood glucose levels are too high, or decrease it if your blood glucose levels are too low. REMEMBER: Most of the time, the appropriate insulin to adjust is the rapid or short-acting insulin taken at the meal before the out-of-goal values. The change should be only 1 or 2 units or 10% of the usual dose at that time of day and can be as small as 1/2 unit. You can make changes every three days. Make a change, evaluate the effect for a few days and then make a change again. You do not need to make big changes. (When blood glucose values are quite variable, extra caution is needed because making even a small change in insulin under these conditions might be dangerous). HINT: Sometimes it is too early for you to see a real pattern. In this case you should probably not make any changes and wait a few more days to see if a pattern emerges. Or, by waiting a few days you might find that your blood glucose levels came back into the goal 15

19 range without any insulin changes. Always make insulin dose changes only after a full examination of the blood glucose levels and do it carefully! If you are unsure, consult with your Diabetes Team. Record Your Blood Glucose for the Past 3 Days and Pick Out the Patterns You See Pre-meal blood glucose goals: Post-meal blood glucose goals: Day # Breakfast Lunch Dinner Bedtime 3 AM 1 Mon 2 Tues 3 Wed Average Pre Post Pre Post Pre Post Based on your results, fill out the answers to the following questions: 1. Do you see a consistent pattern? 2. Which insulin is affecting the pattern of your glucose levels? 3. What kind of change might have helped bring your blood glucose levels into goal range? 4. Do you want to wait a few more days before you make any change to see if there really is a pattern? 5. Have you experienced changes in your stress and/or activity levels over the past three days? 6. Have your food choices or amounts been different than usual for you? 7. Are you experiencing hormonal changes (such as those during menstruation or perhaps related to any medication you may be taking)? 8. Is your pattern of values before breakfast out of the goal range? (If YES, this indicates that you need to change your basal insulin. Please refer to p. 37 for a discussion of this topic.) HINT: Some people find it easier to use a computer program to identify blood glucose patterns. If you are interested in this type of a program, contact your meter manufacturer for information on how to obtain one. 16

20 Correcting for Blood Glucose That is Out of Range Know Your Blood Glucose Goals In this workbook, the American Diabetes Association (ADA) recommended premeal blood glucose goals of 90 to 130 mg/dl will be used. If you are above 130 mg/dl, you will increase your insulin; if you are less than 90 mg/dl you will decrease the insulin. Many people use a target of 100 and make adjustments if they are above or below this target. Correcting The term used for an immediate change in your insulin dose based on one event, such as a: Single out-of-target blood glucose level. Change in a single meal (you are invited out to a French restaurant for dinner). Change in your exercise routine (you are going for a bike ride). Correcting means you make a minor change in your insulin dose based on the event now, but go back to your usual insulin dose tomorrow. EXAMPLE: If you wake up and your blood glucose reading is 200 mg/dl but you want it to be 100 mg/dl, you would make an immediate insulin correction. To do this you would take a certain dose of short or rapid-acting insulin to bring that blood glucose value down to 100 mg/dl. NOTE: Correction doses of insulin are calculated for each person and may change throughout the day. People usually need a bigger correction dose at breakfast than at lunch and dinner. Methods of Correction There are many ways to correct for an abnormal blood glucose value. The three most common methods will be discussed here. Check with your health care professional to see which method is best for you. Correction Method I Fixed Insulin Dose Based on Blood Glucose Value. Uses an algorithm (formula) to tell you the amount of insulin to take based on your blood glucose levels before meals and at bedtime. The carb you eat at each meal should be the same from day to day. EXAMPLE: Ken s Diabetes Team gives him an algorithm of blood glucose values and insulin doses. Ken will give the insulin dose that corresponds to his current blood glucose. 17

21 Ken s Algorithm for Correction Method 1 Blood Glucose Values Insulin Dose (Rapid or Short -Acting) Breakfast Lunch Supper Bed < Over Correction Method I How to Use an Algorithm 1. Use the algorithm for a week or two. 2. Monitor your blood glucose often. 3. Record every reading in your logbook. 4. Share your results by fax, phone or in person with your health team member. 5. Your health team member will work with you to make any needed adjustments to your algorithm. 6. After a little practice, you will be able to use the algorithm with confidence on your own. HINT: Remember, for this method to work well you need to eat the same amount of carbs at breakfast, lunch and dinner from day to day! Correction Method II Change in Insulin Dose Based on Blood Glucose Value Your Diabetes Team prescribes a fixed amount of pre-meal insulin to use for every high, out-of-goal blood glucose reading. Uses an algorithm that tells you how much insulin to add or subtract from your usual dose, depending on your current blood glucose value. EXAMPLE: Joe s fixed dose of rapid or short acting insulin before breakfast and lunch is 6 units, and his pre-dinner dose is 8 units. His doctor gives him an algorithm of blood glucose values and pre-meal rapid- or short-acting insulin. 18

22 Joe s Algorithm for Correction Method II Blood Glucose Values Pre-meal rapid or short acting insulin Less than 60 Subtract 3 units Subtract 1 unit Take usual dose Add 1 unit Add 2 units Add 3 units Add 4 units Add 6 units Over 400 Add 8 units Correction Method III Change in Insulin Dose Based on Your Insulin Sensitivity Factor As you learned earlier, your Insulin Sensitivity Factor (ISF) tells you how many points lower your blood glucose will go for every 1 unit of short or rapid acting insulin you take. Method III uses your ISF to figure out how much to raise or lower your insulin dose to bring your blood glucose back to goal range. If you use Correction Method III before a meal you will need to add the correction amount of insulin to the amount of units needed to cover the number of carbohydrates you will eat. (See p. 28 for a discussion of carbohydrates.) REMEMBER: The ADA recommended pre-meal values of mg/dl as a goal range are used in this workbook. Your Diabetes Team may set a different pre-meal goal for you. Calculating Your Insulin Sensitivity Factor (ISF) Your Diabetes Team may use any of the following methods to help find your ISF: 1. Insulin/Blood Glucose Formula (One unit of rapid or short-acting insulin for every 50 mg/dl increase or decrease in your blood glucose level). 2. Rule of if you are using shortacting insulin (Regular). 3. Rule of if you are using rapidacting insulin (Humalog, Novalog, Apidra ). ISF Method I Insulin/Blood Glucose Formula With ISF Method I, you take one unit of rapid or short-acting insulin for every 50 mg/dl increase or decrease in your blood glucose level. EXAMPLE: Blood glucose target is 100 mg/dl. John s pre-lunch blood glucose is 180 mg/dl and his Insulin Sensitivity is 50. His reading shows that he is above his target by 80 mg/dl. [180 mg/dl 100 mg/dl = 80 mg/dl] He should take 1 (1.5 if you measure 1/2 units) extra units at lunch. If his usual dose of rapid or short-acting insulin at lunch were 12 units, he would increase it by one and take 13 or 13.5 units. 19

23 PRACTICE PROBLEMS: Blood glucose target: 100 mg/dl Susan s pre-lunch blood glucose is 205 mg/dl. Her reading shows that she is above her target by 105 mg/dl [205 mg/dl 100 mg/dl = 105 mg/dl] Q How many extra units should Susan take? 105 mg/dl = 2 units 50 A She should take 2 extra units. In this case she should take a total of 14 units. Bob s pre-lunch blood glucose is 60 mg/dl. His reading shows that he is below his lower target by 40 mg/dl [100 mg/dl 60 mg/dl = 40 mg/dl] Using ISF Method I he would: 40 mg/dl =.8 units 50 Round.8 units to 1 unit Decrease his insulin dose by 1 unit. Take a total of 11 units. Find Your Correction Dose for the Highest Pre-Meal Blood Glucose you had yesterday: ISF = 50 mg/dl Target = mg/dl Pre-Breakfast Pre-Lunch Pre-Dinner Record yesterday s pre-meal blood glucose readings. Take your highest pre-meal blood glucose and subtract your target goal: [ mg/dl =.] Target Goal Divide your answer by 50 and add the number to your usual insulin dose: [ divided by 50 =.] Add to your usual pre-meal dose. If You Had a Low Blood Glucose Yesterday, Figure out the Insulin Dose You Need: Record yesterday s pre-meal blood glucose readings. Take your lowest pre-meal blood glucose reading and subtract your target goal: [ mg/dl =.] Target Goal This will be a negative number. Divide your answer by 50 and subtract the number from your usual insulin dose. [ divided by 50 =.] Subtract from your usual pre-meal dose. The corrections above using ISF Method I should bring your blood glucose back to normal at the next meal if you make no 20

24 other changes. Although any single meal may not correct properly, if after a few days they do not, you may have the wrong ISF or the wrong carb-to-insulin ratio for you. Work with your Diabetes Team would have to adjust the ISF and carb-to-insulin ratio. ISF Method II Using the Rule of 1500 To get a good first guess at your insulin sensitivity, divide the sum of all of your daily insulin doses into EXAMPLE: Calculate Rita s ISF Using the Rule of If Rita took 10 units of Regular insulin at breakfast, 12 at lunch, 13 at supper, and 15 units of Lantus at bedtime, her total would = 50 units a day. Dividing 50 units into 1500 would = 30. So as a first guess, each unit of insulin would lower Rita s blood glucose by 30 mg/dl. (See Rule of 1500 box below) 1) Add all insulin doses 10 units Insulin Regular 12 units Insulin Regular 13 units Insulin Regular + 15 units Insulin Lantus 50 units Rule of ) Divide sum of insulin doses into = 30 mg/dl 50 units of insulin 3) Answer = ISF Insulin Sensitivity Factor = 1 unit of short or rapid - acting insulin will lower blood glucose 30 mg/dl PRACTICE PROBLEMS: 1. Calculate your ISF using the Rule of Fill in all the insulin doses you take in one day and add them up: # of units Type of insulin Divide 1500 by your total units of insulin/day 1500 = (your total units of insulin/day) The answer is your ISF (the number of points one unit of insulin will lower your blood glucose). Total units/day 3 Klingensmith, GJ. American Diabetes Association, Intensive Diabetes Management, Third Edition, p

25 Fill in your pre-meal blood glucose values from yesterday and calculate your adjusted insulin dose using the steps below: Pre-Breakfast Pre-Lunch Pre-Dinner Fill in the table below with your calculations using your own information: Pre-Breakfast Usual Insulin Dose Adjusted Insulin Dose Pre-lunch Circle your high pre-meal blood glucose. Subtract your target goal from your high pre-meal blood glucose. [ mg/dl =.] Target Goal Divide this number by your insulin sensitivity factor (ISF) (ISF) = Add the answer to your usual insulin dose. If you had a low blood glucose yesterday find the insulin dose that should be given: Take your low pre-meal blood glucose your target =. This will be a negative number. You will need to subtract insulin for correction. [ mg/dl =.] Target Goal Divide the number by your ISF and subtract answer from your usual insulin dose. [ divided by =.] Pre-dinner REMEMBER: Guidelines for Taking Correction Doses for Out-Of-Goal Blood Glucose: 1. Check your blood glucose about 2 hours later. Use your post-meal blood glucose goal. In this booklet, the ADA recommendation of less than 180 mg/dl is used. 2. If your blood glucose is still not within your range of blood glucose goals, lower your ISF number (try changing by 5). 3. If you have hypoglycemia (low blood sugar), increase your insulin sensitivity number. ISF Method III Using the Rule of 1700 Another way to get a good first guess at your insulin sensitivity is to divide the sum of all of your insulin doses into Subtract from your usual pre-meal dose. [Usual dose =.] 4 American Diabetes Association, Intensive Diabetes Management, third Edition, p

26 EXAMPLE: If you take 10 units of Humalog at breakfast, 12 at lunch and 13 at dinner, and you take 15 units of Lantus at bedtime, your total would = 50 units a day. Dividing this into 1700 would give you 34 (this number can be rounded up to 35). So as a first guess, each unit of insulin would lower your blood glucose by 35 mg/dl. 1) Add all insulin doses 10 units Insulin Humalog 12 units Insulin Humalog 13 units Insulin Humalog + 15 units Insulin Lantus 50 units of insulin/day Rule of ) Divide sum of all insulin doses into = 34 mg/dl 50 units of insulin 3) Answer = ISF Insulin Sensitivity Factor = 1 unit of short or acting insulin will lower blood glucose 34 mg/dl Now you try it using the 1700 rule. PRACTICE: Calculate Your ISF Using the Rule of Using the chart below, fill in all the insulin doses you take in one day and add them up: # of units Type of insulin Figure out your adjusted insulin dose based on your pre-meal blood glucose readings: Target Goal = Pre-Breakfast Pre-Lunch Pre-Dinner Fill in your pre-meal blood glucose values from yesterday in the chart above. Circle your high pre-meal blood glucose. Total units per day = Divide 1700 by your total units of insulin/day. Subtract your target goal from your high blood glucose reading. mg/dl = Target Goal 1700 (your total units/day) = Divide this number by your ISF. = The answer is your ISF (the number of points one unit of insulin will lower your blood glucose). (ISF) Add the answer to your usual pre-meal dose. 23

27 If you had a low blood glucose yesterday, figure out your correction insulin dose. Subtract your target goal from your low pre-meal blood glucose. mg/dl = Target Goal This will be a negative number. You will need to subtract insulin to make the correction. Divide your answer by your ISF and subtract answer from your usual insulin dose. (ISF) = Subtract the answer from your usual pre-meal dose. = Every time you take a correction dose for an out of goal blood glucose you should note the effect on your blood glucose. If your glucose correction doses never bring you back to your goal range, you should lower your sensitivity number. If you are under-correcting you are not giving enough insulin. You will know this because your high blood glucose readings will remain high and the low blood glucose readings will stay low. This means you need a larger correction dose, so reduce your ISF by 5. If you are over-correcting you are taking to much insulin. You will know this because your high blood glucose values will become low and your lows may become high. This means you need to decrease your correction dose, raise the ISF by 5. Fill in the table below with your calculations using your own information: Pre-Breakfast Pre-lunch Pre-dinner Usual Insulin Dose Adjusted Insulin Dose 24

28 Correcting for Known Changes in Meals or Exercise You have learned to adjust insulin to stay within your blood glucose goals. Insulin doses are also commonly adjusted for changes in diet or exercise. Changing your insulin dose based on what you will eat and the activity you plan to do is often called insulin dosing. Correcting for a Change in Meals Since most people do NOT eat the same thing every day, you need to learn how to calculate your short or rapid acting (bolus) insulin for different meals and different amounts of carbohydrates. If you are not sure about which foods are carbohydrates, discuss this with your diabetes educator. As with insulin correction for out-of-goal blood glucose, different methods are available for insulin dosing for a change in the food that is usually eaten at meals. One method involves adding or subtracting insulin for more or less food. Another way is to take a certain amount of insulin for a specific amount of carbohydrate. Check with your Diabetes Team to see which method they recommend for you. Both methods require that you learn how to count carbohydrates. In addition, you also need to learn how sensitive your insulin dose is to the carb you eat. This is called your Carb:Insulin Ratio. For information about carb counting, see the BD Publication Carbohydrate Counting: Eat to Win and talk to your diabetes educator. Calculating Your Carb:Insulin Ratio A carb:insulin ratio is the amount of rapid or short acting insulin you need to match or cover the amount of carbohydrate you eat. Your ratio depends on how sensitive your blood glucose is to insulin. The more you weigh, the less sensitive your body is to insulin. The more sensitive you are to insulin, the more carbohydrate that will be covered by one unit of insulin. Knowing your ratio and how to calculate your mealtime insulin to match the carbohydrate in your meal gives you the greatest flexibility with improved glucose control. You will be much freer to eat what you want, when you want, with fewer concerns about high or low blood glucose. 25

29 Method I: A Quick and Easy Way to Start Before you begin, keep the following guidelines in mind. Use 1 unit of insulin for every 15 grams of carbohydrate (1:15). Some people will need more insulin (1 unit for every 10 grams of carbohydrate). Others will need less insulin and use 1 unit for every 20 grams of carbohydrate. Most people with type 1 diabetes have ratios between 6 and 10, but you may want to start with a very sensitive level of 15 grams of carbohydrate per unit of insulin and see if this works for you. Method II: The Rule of 500: 5 Add up all the insulin given for 24 hours and divide it into 500. The answer is your carb:insulin ratio. EXAMPLE: Your total insulin dose is 50 units. 500 divided by 50 = 10 Your carb: insulin ratio is 10:1 Again, this is a starting point, you need to start with this ratio and adjust it based on your blood glucose records. Your Diabetes Team can guide you in this process. Keep Detailed Records for About One Week The best way to find your carb:insulin ratio is to use the following Food and Carbohydrate Counting Record below and write down: 1. Everything you eat and how much you eat - you will need to weigh and measure! (If you know how to count carbs, include them. Otherwise, use tables or a calculator to figure out the carbs in all of the food you eat and record each amount.) 2. Your insulin dose for each meal. 3. Your blood glucose levels before the meal. 4. Your blood glucose records after the meal. (Your blood glucose level should increase about 50 mg/dl 2 hours after you eat. If it is much higher or lower than that, your Insulin:Carb ratio will need to be adjusted.) NOTE: If you have never used a carb:insulin ratio, discuss this with your Diabetes Team and let them guide you through this process. Also, like the ISF, you may have a different carb: insulin for each meal. Typically, this ratio is lower at breakfast. 5 Warshaw, H.S. and Kulkarni, K., Complete Guide to Carb Counting. P American Diabetes Association

30 Food and Carbohydrate Counting Record Brkfst time: AM PM Carb goal: gms BG before meal BG 2 hours after meal Insulin Comments: Food Eaten Amount Grams Carb Total: _ Snack Time: Food Eaten Amount Grams Carb Total: Lunch time: AM PM Carb goal: gms BG before meal BG 90 min after meal Insulin Comments: Food Eaten Amount Grams Carb Total: _ Snack Time: Food Eaten Amount Grams Carb Total: Supper time: AM PM Carb goal: gms BG before meal BG 90 min after meal Insulin Comments: Food Eaten Amount Grams Carb Total: _ Snack BG before snack Time: Food Eaten Amount Grams Carb Total: 27

31 Method I Insulin Dosing Based on Carb Intake A set dose of insulin is given for a meal and a specific amount of carbohydrate is eaten at the meal. If you eat the usual amount of carbs, you take the usual amount of insulin. Your health provider will prescribe a specific amount of carbohydrate for each meal. If you eat more carbs, you take more insulin, as determined by your prescribed carb:insulin ratio. If you eat less carbs, you reduce your insulin, again using the ratio. EXAMPLES: George s Health Team prescribed carbohydrates for his meals as follows: 60 grams of carbohydrate for breakfast and lunch. 70 grams of carbohydrates for supper. If George expects to eat more carbs, he will take more insulin, as determined by his prescribed carb:insulin ratio. If he plans on eating less carbs, he will reduce his insulin, again using the ratio. What should George do if he is going to change the amount of food he is going to eat? (George usually eats 70 grams of carb for dinner, and he takes 7 units.) If George is very hungry today and plans to eat 90 grams of carb for dinner, he would eat an extra 20 grams of carb. If his carb:insulin ratio is 10:1, for every 10 extra grams of Carb, he needs 1 extra unit, so for an extra 20 grams, he needs 2 extra units of insulin. In this case, for a 90-gram dinner, he would take 9 units of insulin (see the chart below). Usual Grams of Usual Dose of Carbohydrate Insulin Carb:Insulin Ratio: 10:1 70 Grams Carb 7 Units Humalog 90 Grams Carb 9 Units Humalog 28

32 Method II Insulin Dosing Based on Carb:Insulin Ratio Unlike Method I, you do not have a usual amount of food that you take or a usual insulin dose. You simply use the Carb:Insulin Ratio to determine your dose. EXAMPLE: Mary s Carb:Insulin Ratio is 10:1 Mary is meeting an old friend at a favorite restaurant and she is planning to eat a 90-gram lunch. To figure out her insulin dose, knowing that her ratio is 10:1, all she has to do is to divide the number of carb by her ratio as follows: 90 grams of carbohydrate divided by 10 units of insulin = 9 units of Humalog [ 90 = 9 units of Humalog ] 10 Correcting for a Known Change in Exercise Exercise lowers your blood glucose levels. If you have started an exercise program and your blood glucose levels are too low and you are using an insulin pump, you will need to adjust your basal insulin. (See Adjusting the Basal Dose p. 37). This is the hardest of the adjustments because everyone responds to exercise differently. If you are giving bolus injections of insulin, you should lower your bolus dose before exercise. An example of how to do this can be found on p. 37. Try to measure your exercise by intensity (how hard you work) and how much time it takes. Think of your exercise as mild, moderate or intense. Mild exercise you will not sweat at room temperature, no matter how long you do it. Moderate exercise you will sweat after minutes. Intense exercise you will start to sweat almost right away. The more intense your exercise and the longer it lasts, the more you will need to decrease you insulin. 29

33 PUTTING IT ALL TOGETHER 30

34 PUTTING IT ALL TOGETHER You have learned a lot of information about making changes to your bolus insulin doses. Now it is time to put these facts to work for you. This section will help you practice using your new knowledge in your everyday routine. Getting Started: A Five-Step Plan 1. Define your target blood glucose level. 2. Calculate your insulin sensitivity factor (ISF). 3. Try starting a carb:insulin ratio of 10 or 15 grams of carb:1 unit of insulin. 4. Count the number of carbohydrates you will be eating. 5. Reduce, if necessary for exercise. PRACTICE PROBLEMS: Tom s Night Out Let s look at how Tom uses the 5-step plan above to calculate his insulin adjustment. Tom has a fun evening planned. He is going out to an Italian restaurant for dinner with some friends after a game of singles tennis. When he tests his blood glucose before dinner, he finds it is 190 mg/dl. Here is his information for the five steps. Blood Glucose Goals: mg/dl Target blood glucose level is 100 mg/dl The initial ISF is 1 unit for every 30 mg/dl of blood glucose. Tom s total insulin dose is 50 units/day. Using the rule of 1500, 1500/50 = 30 The initial carb:insulin ratio is 10:1, 1 unit of Regular insulin for every 10 grams of carb. Using the rule of 500, 500/50 = 10 Tom is planning on eating about 90 grams of carbohydrates See below for step 5 Tom s Calculations: Insulin needed for carbohydrates 9 units (90 divided by 10) Insulin needed to correct for high blood glucose Total insulin for food and carb Reduction for high intensity exercise (Step 5) TOTAL amount of pre-dinner insulin ( =90) divided by 30 (ISF)= = 12 units 3 units 9 units 31

35 Your Night Out Using the Five Steps, calculate the answers in the chart below: Planned Food (Carbs) Carbs Divided by Carb/Insulin Ratio Carbs/U of Insulin = Units of Insulin Current Blood Glucose Your Target Blood Glucose Current Blood Glucose Target Blood Glucose Your Insulin Sensitivity Factor? Divide your Blood Glucose Calculation by Insulin Sensitivity Subtract for Exercise if Necessary mg/dl mg/dl mg/dl U of insulin U of insulin Total Dose Your Morning Breakfast and Run Let s say you are going to eat 2 slices of toast (30 grams), a fried egg, hash browns (15 grams) and a 1/2 glass of juice (15 grams). This is a total of (60 grams of carb), but you are going to run 2 miles before lunch. Using the five steps, use the space below to figure out your insulin adjustment based on your plans for breakfast and exercise: Now check the following chart and see how well you did! Your Morning Breakfast and Run Planned Food (Carbs) Divided by Carb/Insulin Ratio Current Blood Glucose 60 Carbs 8 Carbs/U of Insulin 60/8 = 7.5 U of Insulin 180 mg/dl Current Blood Glucose Target Blood Glucose = 80 Insulin Sensitivity 30 Current BG Target BG = 80 = U of insulin Insulin Sensitivity 30 Reduction for Exercise (Should be Negative) Add Units of Insulin (7.5 U U -3 U) = -3 U of Insulin 7 U TOTAL DOSE 32