Type 1 Diabetes Carbohydrate Counting and Insulin Adjustment

Transcription

1 Type 1 Diabetes Carbohydrate Counting and Insulin Adjustment Page 24 Patient Information

2 About this workbook Welcome to this workbook. Some of the topics in the workbook are addressed using a question and answer technique and these sections try to cover the most frequently asked questions. You will also see symbols at various points and these are designed to stimulate discussion or to encourage you to think about the way you manage your diabetes. What do the symbols mean? This symbol indicates something for you to think about, or a question Remember Never exercise if your blood glucose is more than 14 mmol/l and you have ketones. Websites For further information or advice please contact the Paediatric Dietitians at Ashford and St Peter s Hospital NHS Foundation Trust: Tel: E Mail: Catherine.casewell@asph.nhs.uk Sarah.havard@asph.nhs.uk This symbol represents frequently asked questions This is your own personal and private booklet; no one will ask to look at it, so you can keep it private or share it as you wish. Further Information We endeavour to provide an excellent service at all times, but should you have any concerns please, in the first instance, raise these with the Matron, Senior Nurse or Manager on duty. If they cannot resolve your concern, please contact our Patient Advice and Liaison Service (PALS) on or pals@asph.nhs.uk. If you remain concerned, PALS can also advise upon how to make a formal complaint. Author: Dietetics Department: Dietetics Department Version: 3 Published: September 2012 Review: September 2014 Page 2 Page 23

3 o If the exercise is more intense and lasting more than 30 minutes have some extra carbohydrate as advised above. o If the exercise is going to last for more than 45 minutes and is within 2 hours of eating, you can try reducing your insulin dose at that meal by 30-50% instead of eating additional carbohydrate. o If the exercise is going to last more than 45 minutes but is 3 hours or more after eating, you do not need to adjust your insulin dose but should have some additional carbohydrate. General points Introduction As you know more than anyone else, having diabetes is difficult. The more information you can gather about your diabetes, the easier it is to work out what your blood glucose readings mean and to adjust your insulin. During this course we will discuss how food and insulin in particular affect the sugar levels in your blood and we will give you extra information about how to use these things to help you get your control as normal as possible. What we would like to do is: Help you to more closely match your insulin to your food and lifestyle Help you to manage your diabetes better Share your experiences with others like you o Try not to exercise during the time your insulin action is at is peak. o Don t inject insulin into the muscle that is going to be working the hardest. o If you have a hypo after exercise, your stores of glucose will be lower and therefore we recommend that you have 1 and a half times your usual hypo treatment, such as 5 dextrose tablets of 1½ mini cans of Coke. It would be good to start by thinking about a couple of things first: What are your expectations of carbohydrate counting? The things we will be going on to talk about are based on something called DAFNE (Dose Adjustment For Normal Eating) which grown ups use a lot if they have diabetes. We have changed a few things so that you too can now start to use this as a way of managing your diabetes. Some of the ideas also come from people who use insulin pumps because you need to be able to count carbohydrate if you want to use one. Page 22 Page 3

4 So, these things that we are going to talk about are not really new, but we are only just starting to use them for children. Do remember that this way of doing things is not particularly easy. Sometimes people find it too troublesome and difficult so they decide to stop using it or maybe will only use parts of it. Don t feel bad if this happens to you. You can always go back to using it fully later on if you want to. o Young children (up to 7 years old) don t sweat and so don t need commercial isotonic sports drinks as they contain too much sodium. A good home made version is simply normal (full sugar) squash. o After exercise, remember you need to replenish your stores. Glycogen will have been used and so you need to eat a good carbohydrate rich snack within 15 minutes of exercising (you will need insulin with this) and follow this up with a good carbohydrate portion at your next meal. General points o Check your blood glucose levels frequently as this is your only real way of knowing how exercise affects you as an individual. o Keep hydrated by drinking water alongside your isotonic sports drink and also at frequent intervals through the sport and afterwards too. Insulin and exercise It is not possible to give precise guidelines for adjusting your insulin dose due to each of us responding differently to exercise. The only way to be more accurate is to measure your blood glucose before, during and after your exercise so that you can see how exercise affects you. To minimise the risk of exercise related hypos you can try the following: o If the exercise is low intensity such as a walk or playing at school you don t need to have additional carbohydrate or adjust your insulin dose. Page 4 Page 21

5 o Your normal diet should contain enough carbohydrate for normal daily activity such as playing at school or going for a walk. Food and Exercise These rules apply to intense sports and exercise only: o Have a carbohydrate based meal such as pasta 2 hours before exercising for optimum performance. o Additional carbohydrate prior to exercise is only needed if you are exercising for more than 30 minutes. o A good rule of thumb for how much carbohydrate you need for exercise is 1gram of carbohydrate per kilo of body weight per hour of exercise, up to a maximum of 30g. o Don t use chocolate for carbohydrate! Chocolate contains too much fat and so it is digested far too slowly for the muscles to actually use. Avoid low GI slow release carbohydrates. A much better carbohydrate is an isotonic sports drink. Food and Carbohydrate Counting Food is made up of 3 nutrients: Protein Fat Carbohydrate The main type of nutrient in food that affects your blood glucose level is called carbohydrate. Most foods contain a mixture of all 3 nutrients, but foods which contain mainly protein and / or fat will have a minimal effect on your blood glucose levels. Carbohydrates are found in mainly starchy and sugary foods. All carbohydrates are digested into glucose and appear in your bloodstream between 10 minutes and 2 hours after eating. Carbohydrate counting is a system of assessing the quantity of carbohydrate in each meal or snack and injecting the right amount of insulin to match the food you have eaten. Why do people use carbohydrate counting? Food 15g Carbohydrate 30g Carbohydrate Sports drinks 250ml 500ml Jelly babies 20g 40g Fruit juice 125ml + 125ml water 250ml + 250ml water Full sugar 125ml + 500ml water squash Jaffa Cakes 2 4 Page 20 Carbohydrate counting gives you more choice and flexibility in both the type of food you eat and in the timings of your meals. It can also help you maintain your blood glucose levels closer to normal levels. Page 5

6 Which foods contain carbohydrate? Many foods contain a mixture of all 3 nutrients and the main sources are shown in the table below. Exercise management What is aerobic exercise? Aerobic exercise is when muscles are used at a steady pace over a long period of time in a rhythmic way. During aerobic exercise plenty of oxygen is available to the muscles, allowing them to use glucose to provide energy. Examples of aerobic exercise include running, cycling, swimming, playing basketball, roller-skating and dancing. Nutrient Protein Fat Carbohydrate Examples of foods Meat, poultry, fish, eggs, nuts, cheese Butter, oil, margarine, cream Starchy foods, sugary foods, fruit, milk You are more likely to have lower blood sugars after aerobic exercise as glucose has been used for energy. What is anaerobic exercise? Anaerobic exercise is short lasting high intensity activity. There is no oxygen available to the muscles in anaerobic exercise so glucose cannot be used for energy. Examples of anaerobic exercise include sprinting and weight lifting. Often certain positions in team sports such as football can be anaerobic as short sprints occur infrequently. Protein foods alone will have little effect on your blood glucose levels, but some protein foods have carbohydrate added during processing. This may be flour or a cereal; examples of these are sausages, fish fingers, chicken nuggets or pastry goods such as quiches, pies and sausage rolls. You can check the food label for more information. We will cover this later on. Fat has little effect on glucose levels after eating, but a large amount of fat can slow down the digestion of a meal and make your blood glucose levels rise more slowly. Examples of high fat foods which have this effect are fish and chips, burger and fries, Chinese or Indian meals from a takeaway or restaurant. Carbohydrate foods will have the greatest effect on your blood glucose levels after eating. They include all starchy and sugary foods. Page 6 You are more likely to have high blood sugars after anaerobic exercise. Why can hypo s be more difficult to detect during exercise? Many of the recognised symptoms of a hypo are often experienced during normal exercise, for instance feeling hot and sweaty and noticing an increased heart rate. Checking your blood glucose will help you to make the necessary adjustments. A previous hypo within the last 24 hours may increase your risk of further hypo s and this risk is further increased by exercise. Activity o Are you truly exercising or just being active? Often PE lessons at school are not intense enough to count as exercise. Page 19

7 Snacks If your snack contains less than 20grams of carbohydrate you may not need any extra insulin. However if want to have a larger snack you may need to give yourself some insulin. Let s practice: My insulin to carbohydrate ratio is.. I want to eat a sandwich after school How much carbohydrate does it contain?... Starchy foods All starchy foods contain carbohydrate. Examples of these include: rice pasta noodles bread breakfast cereals grains such as cous-cous and bulgar wheat flour and foods made from flour such as pastry, pizza bases, sauces plain biscuits, crackers starchy vegetables such as potatoes, yam, sweet potato, lentils, beans and dried peas Will I need to give extra insulin?... If yes, how much will I need to give?.. Before you give yourself insulin consider the answers to the following questions as these may alter your insulin dose: o Is my blood glucose within the target range or do I need to give myself a correction dose? o Have I eaten any carbohydrate within the last two hours as this may be why my blood glucose is a bit high? o Have I injected any insulin in the last two hours? Remember fast acting insulin may still be in your body for up to 6 hours after injecting. o Am I planning to do any exercise? Page 18 Page 7

8 Sugary foods There are 3 main categories of sugary foods and all will raise blood glucose levels after eating: Any food made with ordinary sugar called sucrose contains carbohydrate. These foods include cakes: biscuits chocolate sweets jam, honey, marmalade puddings, desserts squashes, fizzy drinks Fruit contains natural sugar called fructose which is also a form of carbohydrate: fresh fruit dried fruit frozen fruit fruit juices and smoothies Blood Glucose Monitoring Measuring blood Glucose is a way of checking your diabetes. By using the blood test results you can learn how different things can affect you, such as the food you eat, the exercise you take, or illness or if you are worried or upset about something. Blood Glucose monitoring will help you see what s working and what is not working. Try not to worry about them too much. Instead, try to see them as information that you can use to help you change things if you need to. Correction Doses Your Paediatric Diabetes Consultant or Diabetes Specialist Nurse will have given you a correction dose of insulin that you need to give if your blood sugars are not within the normal range. You still need to apply this to your total insulin that you have calculated you need to give. Milk and milk products contain natural sugar called lactose. All milk contains carbohydrate including: full cream, semi skimmed and skimmed milk long life, pasteurised, homogenised custard ice cream yoghurt and fromage frais Page 8 Page 17

9 Applying the insulin to carbohydrate ratio to food Go back to page 10/11 to where you calculated the amount of carbohydrate in rice, breakfast cereal and the pepperoni pizza. Let s practice! 200g cooked rice contains. g carbohydrate If I eat this I need to bolus... units insulin My bowl of breakfast cereal weighs. g This contains... g carbohydrate If I eat this I need to bolus. units insulin The whole pepperoni pizza contained g carbohydrate If I eat this I need to bolus..units insulin How do I work out the carbohydrate content of my food? There are different ways to do this and we will learn more and practice each of these in turn. Weighing food You can weigh your food using digital kitchen scales and work out the amount of carbohydrate in your portion by using food charts or food tables. This system is useful for foods like breakfast cereals, potatoes, pasta and rice as portion sizes can vary quite a lot between different people. You need to weigh food in grams (g) rather than ounces (oz) as most food tables will give you the amount of carbohydrate per 100g. You can work out the amount of carbohydrate by doing the following: weigh the food in grams and note the weight Look up the amount of carbohydrate per 100g in your food table for the food you are eating and make a note of it Divide the amount of food you have weighed by 100 Multiply the result by the amount of carbohydrate per 100g from the food table Or you can use the following formula: Weight of food in grams x amount of carbohydrate per 100g 100 Let s practice! Page 16 Page 9

10 Take out your food tables and scales, and use the rice and breakfast cereal to complete the following exercise: A portion of cooked rice weighs 200g Use your food tables to find out how much carbohydrate it contains per 100g How much carbohydrate is there in the 200g portion? A portion of your usual breakfast cereal weighs: Let s practice! Have a go at calculating your own insulin to carbohydrate ratio using the 500 rule: My total daily dose is.. Divide 500 by this My insulin to carbohydrate ratio is 1 unit of insulin for every... grams of carbohydrate A second and more accurate way to calculate your insulin to carbohydrate ratio is to keep a food diary (see separate food diary).. Use the food tables to find out how much carbohydrate it contains per 100g The 500 rule is a good starting point but you may want to use both methods and take the mid point for a more accurate ratio. How much carbohydrate is there in your portion?.. Page 10 Page 15

11 The way you can check to see if your meal insulin dose is right for you is to see if your blood glucose is between 4 and 9 mmol/l l 2 hours after you have eaten. If it is higher than this you may need more insulin with your food. Calculating your insulin to carbohydrate ratio The amount of insulin you need with food is called your insulin to carbohydrate ratio. This ratio is different for each person. There are two ways of calculating this ratio: One way is to use the 500 rule to estimate how many grams of carbohydrate one unit of insulin will cover. To calculate this you will need to add up your total daily insulin dose and divide it into 500. For example: Total daily dose Calculation Insulin to carbohydrate ratio 20 units 500 / units 500 / If your total daily dose varies a lot you will need to look back over the last 5 to 7 days and add them together to take an average. The average number is what you divide into 500. Remember you will need to recalculate your insulin to carbohydrate ratio every time your total daily dose changes significantly. If the new insulin to carbohydrate ratio is very different you may feel happier to make the change in stages rather than all at once. Food labels Many food manufacturers now supply nutritional information on the label about the carbohydrate content of that food. Remember that you have to count the total carbohydrate and not just the sugars. The information can be shown as either per 100g or per portion. If you use the value per 100g then you will need to know the weight of the portion you are eating and you can use the formula above to work out the carbohydrate content. You may find the information per portion more useful, but remember that your portion size may not match that recommended by the manufacturer. Let s practice! Pepperoni Pizza 300g Per 100g Per 150g serving Energy 275kcal 412kcal Carbohydrate 25.3g 38g (of which sugars) 3.4g 5.1g Fat 12.4g 18.6g This is an example of a label with nutritional information for a pepperoni pizza. It gives you the information both per 100g and for a 150g serving (which is half the pizza). If you ate the whole pizza how much carbohydrate would you have eaten?... Page 14 Page 11

12 Helpful information Keeping a record Once you have weighed your usual portion sizes and calculated how much carbohydrate each food contains, it may be worth keeping this information in an index file or A-Z index book so that you can refer to the information each time without having to re-weigh foods. However as you grow and your appetite changes your portion size may vary, so it s worth double checking that your figures are still up to date every now and again. Eating out Many people find it a challenge to try and calculate the amount of carbohydrate in foods and meals eaten away from home. As you become more practiced at working out the carbohydrate content of the foods you normally eat, you will find it easier to estimate just by looking at how much carbohydrate is in the foods order. Snacks Carbohydrate counting means you can decide to have snacks based on your personal choice. If your snack contains more than 20g carbohydrate you may need to take extra insulin with it, or if you don t want to have an extra injection you may decide to wait until the next meal. You can have as much carbohydrate free food as you wish without the need for an extra injection as this won t affect your blood glucose levels. Some examples include: Lean meat e.g. ham, turkey, beef Fish e.g. tuna, mackerel, smoked salmon, prawns Eggs Hard cheeses e.g. cheddar, Cheshire, edam Vegetables e.g. carrot sticks, celery, tomato, cucumber Insulin Dose Adjustment The background insulin is usually injected once a day at bedtime and is called: LANTUS (also called glargine) or LEVEMIR (also called Detemir) Can you remember what your background insulin is called? The way you would check to see if your background insulin dose is right for you is to see if your blood glucose is between 4 and 9 mmol/l at breakfast time. If it is consistently higher or lower than this it may need adjusting. The insulin usually injected with each of your meals is very fast acting and is called: NOVORAPID or HUMALOG LISPRO What is your fast acting insulin called? Page 12 Page 13