Initiating and Adjustment of the Insulin Pump. Celia Levesque RN, MSN, CNS-BC, NP-C, CDE, BC-ADM Normal Insulin Secretion

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1 Initiating and Adjustment of the Insulin Pump Celia Levesque RN, MSN, CNS-BC, NP-C, CDE, BC-ADM Normal Insulin Secretion 1

2 Candidate Selection Desires insulin pump Check BG frequently Able to operate pump Able to afford pump Able to troubleshoot Works with medical team Hypoglycemia Busy schedule Athletes Dawn phenomenon Elevated HbA1c despite best efforts Gastroparesis Pre Pump Education Carbohydrate counting Insulin to carbohydrate ratio Sensitivity factor Sick day management Prevention of DKA / ketone testing Hypoglycemia treatment BG testing / BG goals / record keeping Calculating insulin pump doses 1. Calculate the total pump total daily dose (TDD) 2. Calculate a single basal rate 3. Calculate the insulin to carb ratio 4. Calculate the correction factor 5. Choose a target BG range 6. Choose the active insulin time Calculating Total Pump Total Daily Dose (TDD) Method 1: Pre-pump TDD x 0.75 Method 2: Weight: kg x 0.5 OR lb. x 0.23 Clinical considerations Average values from methods 1 & 2 Frequent hypoglycemia: start at lower dose Hyperglycemia, HbA1c, preg: start higher dose Grunberger, G, Abelseth, J., Bailey, T, et. al. Consensus statement by the American Association of Clinical Endocrinologist/American College of Endocrinology Insulin Pump Management task force. Endocrine Practice. 2014;20(5): Example: Calculate Pump TDD Average total daily dose = 50 units, Weight = 100 kg Method 1: 50 units x 0.75 = 37.5 Method 2: 100 x 0.5 = 50 Average: =

3 Initial Single Basal Rate (50% TDD) Pump total daily dose x hrs = basal Or Pump total daily dose 48 = basal rate Example: TDD = 30 units 30 x 0.5 = hours = units per hour Carbohydrate Ratio 450 TDD before pump Alternate methods: 6 x wt. in kg TDD or 2.8 x wt. in lb. TDD Fixed Meal Bolus = TDD x equal meals Continue existing CR from MDI regimen Example: Total dose before pump = 45 units = 10 1 unit for every 10 grams of carbohydrate Sensitivity/Correction Factor 1700 Pump TDD Example: Total pump dose = 85 units = 20 1 unit will decrease the BG by ~ 20 mg/dl 3

4 Calculate the following: Sally is a 12-year-old female with type 1 diabetes since age 4 and no other health issues. She is very active and is a cheerleader at school. She has never had severe hypoglycemia. She uses Humalog for her meals and correction of hyperglycemia. Her most recent HbA1c is 8.2%. Her weight is 41.5 kg and her pre pump total daily dose is 29 units Pump Total Daily Dose (PTDD): Method 1: units TDD x 0.75 = Method 2: kg x 0.5 = Average: method = Insulin to Carbohydrate ratio: 450 pre pump TDD = Sensitivity Factor based on Average pump total daily dose 1700 pre pump total daily dose = Single basal rate based on average total pump dose pump total daily dose 2 24 hours = units per hour What target BG would you select? What active insulin time would you select? 4

5 Calculate the following: Mr Washington is a 56-year-old male with type 1 diabetes for 35 years. He has hypoglycemia unawareness with 3 episodes of severe hypoglycemia. He has widely fluctuating BG levels, a history of stable stage 3 chronic kidney disease and stable treated proliferative diabetic retinopathy. He exercises most days of the week. His most recent HbA1c is 7.4%. His weight is 90 kg and his pre pump total daily dose is 72 units per day. Pump Total Daily Dose (PTDD): Method 1: units TDD x 0.75 = Method 2: kg x 0.5 = Average: method = Insulin to Carbohydrate ratio: 450 pre pump TDD = Sensitivity Factor based on Average pump total daily dose 1700 pre pump total daily dose = Single basal rate based on average total pump dose pump total daily dose 2 24 hours = units per hour What target BG would you select? What active insulin time would you select? 5

6 Calculate the following: Ms. Thompson is a 24-year-old female with type 2 diabetes since age 16. She does not have any diabetes related long-term complications. She is not active. She weights 120 kg and her pre pump total daily dose is 140 units. Pump Total Daily Dose (PTDD): Method 1: units TDD x 0.75 = Method 2: kg x 0.5 = Average: method = Insulin to Carbohydrate ratio: 450 pre pump TDD = Sensitivity Factor based on Average pump total daily dose 1700 pre pump total daily dose = Single basal rate based on average total pump dose pump total daily dose 2 24 hours = units per hour What target BG would you select? What active insulin time would you select? 6

7 Continuous Glucose Monitoring Measures interstitial fluid glucose Subcutaneous catheter attached to a transmitter The receiver displays a new result every 5 minutes o Pump screen o Stand alone receiver o Phone Interstitial Fluid Glucose Does not always match blood glucose Interstitial glucose lags behind blood glucose The faster the change in BG, the greater the difference between IFG and BG What happens between finger sticks? Benefits of CGM Reduce risk for hypoglycemia secondary to alarms Reduce risk for extreme hyperglycemia secondary to alarms Reduce risk for wide BG fluctuations Behavior modification / learning 7

8 INSULIN PUMP FINE TUNING The insulin pump is a great tool to manage diabetes in those requiring insulin. However, from time to time, the rates may need to be adjusted. The purpose of the basal rate is to keep the blood sugar within target range when NOT eating. The purpose of the meal bolus is to keep the blood sugar within target after eating food. The purpose of the correction/sensitivity factor is to correct high blood sugar back to target. None of the following tests should be done when you are sick, or when other unusual circumstances are going on. You should perform these tests ONLY with the knowledge and guidance of your healthcare provider. When testing BASAL RATES, one should not eat or exercise during the test. Do not eat a high fat meal just prior to starting the test. Start the test ONLY if the starting blood sugar is within your target range. The goal of the basal rate is to keep your blood sugar from rising or falling by more than 30 mg/dl from your target. When testing MEAL BOLUSES, only start the test when your blood sugar is within target before the meal you are going to test. Eat a meal with a known number of grams of carbohydrate. Do not eat mixed meals like pizza or casseroles. The goal is to have your blood sugar rise no more than 50 mg/dl. When testing SENSITIVITY/CORRECTION BOLUSES, only start the test when your blood sugar is at least 50 mg/dl above your target. Perform the test when you have not taken a bolus or eaten any food for 4 hours and you can go without eating for an additional 4 hours. The goal is to have your ending blood sugar within 30 mg/dl of your target. 8

9 TESTING OVERNIGHT BASAL RATE INSTRUCTIONS Test 1 Test 2 Test 3 BEFORE DINNER BLOOD SUGAR Within target? Continue the test. 2 HOURS AFTER DINNER Over 50 mg/dl (2.8 mmol/l) higher than pre-dinner glucose? Stop test. Start test again tomorrow night with an adjusted dinner bolus. BEDTIME Under 100 mg/dl (5.6 mmol/l)? Stop the test and eat a snack. Start test again tomorrow night with an adjusted meal bolus. Over 250 mg/dl (13.9 mmol/l)? Stop test. Follow high glucose guidelines. Start test again tomorrow with adjusted basal rate. OVERNIGHT (half way through your sleep cycle) Under 90 mg/dl (5 mmol/l)? Stop test and eat a snack. Start test again tomorrow night with an adjusted basal rate. Over 250 mg/dl (13.9 mmol/l)? Stop test. Follow high glucose guidelines. Start test again tomorrow night with adjusted basal rate. BREAKFAST TIME (Do not eat breakfast!) Under 70 mg/dl (3.9 mmol/l)? Treat low and stop test. Start test again tomorrow night with an adjusted basal rate. Over 250 mg/dl (13.9 mmol/l)? Stop test. Follow high glucose guidelines. Start test again tomorrow night with an adjusted basal rate. 2 HOURS AFTER BREAKFAST TIME Same instructions as breakfast time. 4 HOURS AFTER BREAKFAST TIME Same instructions as breakfast time. BEFORE LUNCH (Eat Lunch!) Take lunch bolus and any necessary correction bolus. Call your healthcare provider for your basal rate adjustment. 9

10 TESTING DAYTIME BASAL RATE INSTRUCTIONS Test 1 Test 2 Test 3 BEFORE BREAKFAST Within target? Continue the test. 2 HOURS AFTER BREAKFAST Over 50 mg/dl (2.8 mmol/l) higher than pre-breakfast glucose? Stop test. Start test again tomorrow with an adjusted breakfast bolus. LUNCHTIME (Do not eat lunch!) Under 70 mg/dl (3.9 mmol/l)? Treat low and stop test. Start test again tomorrow with an adjusted basal rate. Over 250 mg/dl (13.9 mmol/l)? Stop test. Follow high glucose guidelines. Start test again tomorrow with an adjusted basal rate. 2 HOURS AFTER LUNCHTIME Same instructions as lunchtime. 4 HOURS AFTER LUNCHTIME Same instructions as lunchtime. 6 HOURS AFTER LUNCHTIME Same instructions as lunchtime. DINNERTIME (Eat Dinner!) Take dinner bolus and any necessary correction bolus. Call your healthcare provider for your basal rate adjustment. BEFORE BREAKFAST Within target? Continue the test. 10

11 TESTING EVENING BASAL RATES INSTRUCTIONS Test 1 Test 2 Test 3 BEFORE LUNCH Within target? Continue the test. 2 HOURS AFTER LUNCH Over 50 mg/dl (2.8 mmol/l) higher than pre-lunch glucose? Stop test. Start test again tomorrow with an adjusted lunch bolus. DINNERTIME (Do not eat dinner!) Under 70 mg/dl (3.9 mmol/l)? Treat low and stop test. Start test again tomorrow with an adjusted basal rate. Over 250 mg/dl (13.9 mmol/l)? Stop test. Follow high glucose guidelines. Start test again tomorrow with an adjusted basal rate. 2 HOURS AFTER DINNERTIME Same instructions as dinnertime. 4 HOURS AFTER DINNERTIME Same instructions as dinnertime. 6 HOURS AFTER DINNERTIME Same instructions as dinnertime. BEDTIME If you would like a snack, take a snack bolus and any necessary correction bolus. Call your healthcare provider for your basal rate adjustment. BEFORE LUNCH Within target? Continue the test. 11

12 TESTING MEAL BOLUS INSTRUCTIONS Test 1 Test 2 Test 3 PRE-MEAL Count carbohydrate and take meal bolus Carbohydrate = grams Meal bolus = units (1 unit/ grams of CHO) 2 HOURS POST MEAL 3 HOURS POST MEAL 4 HOURS POST MEAL TESTING CORRECTION FACTOR INSTRUCTIONS Test 1 Test 2 Test 3 BEGINNING Take correction bolus now = units 1.0 unit for mg/dl (mmol/l) 1 HOUR 2 HOUR 3 HOUR 12

13 Overnight Basal Test Morning Basal Test 13

14 Bolus Test Bolus Test 14

15 Correction Factor Test Correction Factor Test 15

16 Troubleshooting Hyperglycemia Insulin Loss of potency Wrong insulin in pump Infusion set Bent catheter Air in tubing Infusion site problem Insulin pump Programming error Pump malfunction Behavior Missed bolus Bloused after eating Did not correct Miscount CH Blood Glucose Over 250 mg/dl Take correction bolus via pump. Recheck BG in 1 hour. If BG decreasing, no further action needed If BG not decreasing then check ketones and. Negative Ketones Positive ketones 1. Inject insulin using a syringe according to 1. Contact healthcare provider or go to the correction factor nearest emergency department if urine ketones 2. Drink 8 oz sugar-free fluid every 30 min are moderate or large or if the betahydroxybutyrate is 0.6 or greater or if you have 3. Recheck BG in 1 hour 4. If BG is decreasing change reservoir and nausea or vomiting. infusion set with fresh insulin and fresh 2. Do not use the pump while ketones are injection site positive. Only inject insulin with a syringe using 5. If BG not decreasing with injection, insulin the correction factor and target blood glucose. may be bad or dehydration, or illness. 3. Consume 8 ounces of sugar-free fluid every Change vials of insulin and inject again 30 minutes if possible and contact provider or go to emergency 4. Continue checking blood glucose and ketones department. Continue checking BG and every 1 hour ketones every 1 hour and drink sugar-free 5. Inject rapid acting insulin every 2-3 hours fluids if possible according to the correction factor and target BG Beta-hydroxybutyrate Precision Xtra = call MD 1.5 = go to ER NovaMax = call MD 1.5 = go to ER Supplies Needed Insulin Syringes Pump supplies Monitoring supplies Hypoglycemia treatment Ketone testing: urine/blood DM identification Glucagon 16

17 Hypoglycemia 20% of T1DM will die from hypoglycemia 40% of T1DM will have severe hypo if duration of > 15 years Annual rate of severe hypoglycemia requiring emergency medical services: 7.1% Mortality rate 1 year after severe hypoglycemia T1 & T2 combined = 17% BG< 70 mg/dl: Type 1 DM vs. Non DM No Diabetes Type 1 Diabetes / Low C-Peptide Insulin levels drop Insulin levels high because of injected insulin Glucagon secreted Glucagon not secreted Epinephrine release Epinephrine release Norepinepherine Norepinepherine Cortisol release Cortisol release Growth hormone Growth hormone Neurotransmitters Neurotransmitters Severe Hypoglycemia Treatment: Glucagon Converts glycogen to glucose 1 kit = 1 mg raises BG ~ 50 mg/dl Given SC, IM, or IV 1 mg for child > 4 ½ mg for child < 4 Mini Dose Glucagon Pt unable to swallow CHO but is awake & alert with BG < 80 mg 2 units for 1 yo 1 unit per year of age for 2 years & older Max 15 units If not above 80 mg/dl in 30 min, double the dose (max 30) Carbohydrate Counting Counting CHO: Reading Labels 1. Look at serving size 2. Decide how many servings will be consumed 3. Multiply the servings by the total grams of CHO 17

18 Effects of CHO, Fat & Protein on BG 18

19 Total Available Glucose Nutrient Foods Effect on BG Duration of effect Carbohydrate 4 cal/gm Simple: fruit juice, jam 100% 5 min 3 hours honey, table sugar, milk, fruit Complex: legumes, grains, beans vegetables peas, cereals, bread, crackers rice, corn potatoes, pasta Protein 4 cal/gm Meat, eggs, tofu, 58% 3-6 hours cheese, peanut butter Fat 9 cal/gm Unsaturated: liquid oils Nuts, some margarines Saturated fats: animal fat, coconut and palm oils 10% 8 hours Alcohol 7 cal/gm Beer, wine, hard liquors May cause low BG Unpredictable Adapted from: pdf Total Available Glucose 19

20 Bolus for Cheeseburger, onion rings, and shake Adapted from Chase et al: Diabetic Medicine 2002;19: Exercise Most studies show little impact on A1c for T1DM Benefits of exercise same as non DM If exercise performed within 90 min of a meal, may reduce mealtime bolus Bolderman, K. M. (2012). Putting your patients on the pump: Initiation and maintenance guidelines (2 nd ed). Alexandria, VA: American Diabetes Association. Metabolic Response to Light & Moderate Exercise Normal Insulin level decreases Glucagon increases Free fatty acid mobilization increases Restriction of glucose by non exercising skeletal muscle T1DM Insulin level fails to change at the onset of exercise Insulin excess: muscle glucose uptake exceeds liver glucose production Insulin deficiency: liver glucose production exceeds muscle uptake; FFA release and ketone body formation increase Adequate insulin: liver glucose output matches muscle glucose uptake Bolus Reduction if Exercise within 90 minutes after a meal Short duration minutes Moderate duration minutes Long duration > 60 minutes Low intensity - 10% - 20% - 30% Moderate intensity - 25% - 33% - 50% High intensity - 33% - 50% - 67% 20

21 CHO Replacement gm/30 min of Exercise Weight 50 lb. 23 kg 100 lb. 45 kg 150 lb. 68 kg 200 lb. 91 kg 250 lb. 114 kg Light activity Moderate Intense Basal Adjustment for Prolonged Activity Exercising < 90 minutes: do not change basal Exercise > 2 hours o Starting point: decrease basal by 50% o If more intense activity: 70-80% reduction o Start reduction 1-2 hrs before prolonged exercise o Resume full basal rate prior to stopping prolonged exercise o Delayed hypoglycemia may occur after prolonged/intense activity Exercise Induced Hyperglycemia Weight lifting Intermittent bursts of activity (softball, golf, martial arts, sprints, judged events If hyperglycemia is consistent: o Take extra insulin in preparation: 50% of the amount expected to offset the rise in BG: give min before the expected rise Hyperglycemia Prior to Exercise Lack of insulin o If explainable: hydrate, take 50% of usual correction bolus o If unexplainable: Check ketones If negative: hydrate, take 50% of usual correction bolus, exercise If positive: hydrate, administer full correction dose, hyperglycemia protocol, do not exercise Special Situations Kids Pregnancy Illness Menstrual cycle Sex Travel Surgery Steroids Gastroparesis Kids & Pumps Pump therapy in kids requires commitment and motivation on the part of caregivers Children require frequent dose changes Tend to need more bolus and less basal insulin compared to adults Teens are usually insulin resistant 21

22 Kids & Pumps: Common problems Missed boluses Bent catheters CHO counting is an adult concept Not finishing meal after bolus given Unpredictable, impulsive, erratic activity 3-4 year olds Can deliver bolus but needs to verify amt before activating Use block feature in young kids 7-12 year olds Tend to be excited about pump Need help deciding on how much to bolus Begin to carb count can calculate insulin to carb ratio Usually can achieve good control Teens: Least reliable group Learn quickly Preoccupied with many other things, Pump not priority Forget to bolus Do better on a pump than shots but not as good as younger kids NEED PARENTAL INVOLVEMENT Pumps in school Train teachers & school nurse Care plan for pump issues Phone numbers for diabetes care team Extra insulin for pump &/or insulin pen for injection Pump supplies, numbing cream if used Ketone and glucose testing supplies Pump batteries Insulin syringe and/or pen needles Pumps on the playing field If NOT going to detach: o May need to reduce basal rate o May consume CHO if needed If going to detach: o Less than 1 hour: no adjustments o Bolus q 1 hr during breaks for missing basal o Small bolus with snacks during breaks Pregnancy Target BG: Premeal: mg/dl Post meal 1 hr.: < 130 mg/dl Target HbA1c: < 6% If frequent hypoglycemia, severe hypoglycemia, or hypoglycemia unawareness: customize target BG 22

23 Evaluate control twice weekly and adjust Pregnancy: BG > 200 follow same rules as non-pregnancy for hyperglycemia treatment but with blood glucose over 200 mg/dl instead of over 250 mg/dl Labor and Delivery Follow the hospital protocol Hourly blood glucose checks BG goal mg/dl For elective C-section: decrease basal rate by 30% 8 hours before delivery while NPO and if prone to hypoglycemia, reduce 50% Active labor: reduce basal rate 30-50% Reduced insulin requirements after delivery Illness Frequent BG and ketone testing Need basal to prevent DKA Do not reduce basal unless hypoglycemia Basal rates may need to be increased for fever, infection, surgical stress, etc. Use hyperglycemia protocol as previous outlined If prolonged fasting: sensitivity factor may need to be changed Illness Increase non caloric fluids Need some CHO to prevent ketosis If can t eat solid food: may substitute with liquid CHO Teach pt. to call if: o Fever > 100 o Nausea, vomiting, diarrhea > 4 hrs. o Moderate or large urine ketones, or > 0.6 on betahydroxybuterate test Menstrual Cycle Effect on BG varies Increased insulin requirements 2-3 days to 1 week before cycle due to changes in estrogen and progesterone causing insulin resistance Decreased insulin requirements the day after cycle starts May need to adjust both basal and bolus Travel If sedentary during the travel: may need temp increase in basal rate 10-20% Bring 50% more pump supplies than usually needed for the time away o Spare pump if available o Hypoglycemia treatment including glucagon o Extra insulin, syringes, monitoring supplies Know where the nearest pharmacy, and medical care available Pack all medical supplies in a carry on bag, Extra glasses if needed Insulin stable for days at room temperature, Protect insulin from extreme heat Low dose x-ray screening and total body scanners: contact pump manufacturer Check with airline and TSA for any changes in rules When changing time zones: 23

24 o Keep the pump clock the same at departure and then change it to the new time zone after arriving to the new destination o If a large time zone change o Change pump clock 2 hours towards the new destination daily until the correct time is achieved Surgery/Procedure What type of surgery? How long is the surgery? What time will the surgery start? How long will the patient fast? What kind of diet will the patient have after surgery? Will the patient be receiving IV dextrose? What type of anesthesia? Can the patient skip a meal without hypoglycemia? Does the patient have a history of severe hypoglycemia? Does the patient have hypoglycemia unawareness? General Anesthesia Neuroendocrine stress response o Epinephrine o Glucagon o Cortisol o Growth hormone Inflammatory cytokines o interleukin-6 o tumor necrosis factor-alpha Metabolic Abnormalities from Surgery/Anesthesia Insulin resistance Decreased peripheral glucose utilization Impaired insulin secretion Increased lipolysis and protein catabolism Hyperglycemia In some cases: ketosis General anesthesia is associated with larger metabolic abnormalities as compared to epidural anesthesia Glycemic Goals for Surgery Avoidance of marked hyperglycemia Avoidance of hypoglycemia Maintenance of fluid and electrolyte balance Prevention of ketoacidosis Options: Take pump off and replace basal insulin: o 1 injection of basal prior to surgery o ½ dose prior to surgery, ½ dose 12 hrs. later 24

25 o Patient given corrections for hyperglycemia using Regular or Rapid-acting analog insulin Leave pump on at full basal rate o Patient given corrections for hyperglycemia using Regular or Rapid-acting analog insulin Leave pump on at reduced basal rate Patient given corrections for hyperglycemia using Regular or Rapid-acting analog insulin Gastroparesis Stomach emptying is variable Many have gastroparesis without sx Use special bolus features as needed to match stomach emptying Generally: gastroparesis diet is low fat, low fiber Steroids Steroid Equivalent Onset Duration Betamethasone mg Rapid Cortisone 1 25 mg Slow h Dexamethasone mg Rapid 72 hours x > than HC 5-7 x > Prednisone HC acetate 1 20 mg Slow Long HC sodium phosphate 1 20 mg Rapid Short HC sodium succinate 1 20 mg Rapid Short MP 5 4 mg Rapid h Prednisolone 4 5 mg Rapid h Prednisone 4 5 mg Rapid Low dose steroids: less than equivalent of Dexamethasone 40 milligrams o 40% basal o 60% bolus High dose steroids: equivalent of Dexamethasone 40 milligrams or higher o 25% basal o 75% bolus o Steroids Total initial insulin dose: o Low dose steroids: start at units/kg o High dose steroids: start at: 0.9 units/kg if on metformin 1.2 units/kg if not on metformin 25