Being physically active after eating can reduce postmeal spikes in a number of ways. In addition to helping insulin absorb and act more quickly, muscle activity diverts blood flow away from the intestines, resulting in slower absorption of sugars into the bloodstream.
7. Prevent Hypoglycemia
Low blood sugar is problematic in many ways. One of the body’s responses to hypoglycemia is accelerated gastric emptying: food digests and raises blood sugar even more quickly than usual. Although this is a desirable effect for anyone experiencing hypoglycemia, when it occurs soon before meals, it can contribute to excessive postmeal spikes. Preventing hypoglycemia prior to meals and snacks is yet another strategy to “strike the spike.”
Troubleshooting Routine Highs
Everyone with diabetes experiences blood sugars that are above target from time to time. Individual, out-of-the-blue highs can be caused by any number of factors. Before assuming that your basal doses or bolus calculation formulas require permanent adjustment, consider these common culprits, many of which were described in detail in Chapter 8 :
• undercounted carbs
• accidental underdosing of insulin
• intentional underdosing of insulin (diabulimia) or hypoglycemia anxiety
• anxiety or stress
• caffeine
• disease progression
• binge eating
• protein (in the absence of carbs)
• large amounts of dietary fat
• growth and weight gain
• illness or infection
• reduced physical activity
• rebounds from lows
• hypothyroidism
• steroid medications
• surgery
• gastroparesis
• travel
• intense or competitive exercise
• irregular sleep
• premenstrual hormones
• menopause
• latter stages of pregnancy
And if none of these seem to be the answer, it is very possible that the Diabetes Gods, at this particular point in time, are just out to smite you. Hey, it happens.
When unexplained above-target blood sugars occur back-to-back, there are certain troubleshooting questions that you should ask:
Is my insulin spoiled?
Did I forget to take my insulin?
Is my insulin absorbing properly?
Is there a gap in my insulin coverage?
For pump users: Has my pump or infusion set malfunctioned?
Let’s take a look at these one at a time.
Spoiled Insulin
Using spoiled insulin can lead to high blood sugar and ketone production. Insulin that has been frozen or exposed to extreme heat can denature, or break down so that the insulin molecules no longer work. Using the same vial or cartridge of insulin for many months or using it well past its expiration date can also cause serious problems.
Prevention: Try not to use insulin vials and cartridges past their expiration date.
Once a vial or cartridge is put into use, discard it after a couple of months (the insulin makers recommend starting new insulin vials and pens monthly).
Store your unopened insulin in the refrigerator in an area that is not likely to freeze, such as the door.
Before using a new insulin vial or cartridge, look for clumps, crystals on the glass, or discoloration.
If you suspect that the insulin has gone bad, it probably has.
When ordering insulin by mail, ask that it be shipped in a temperature-controlled container, and ask for a temperature-sensitive tag in the shipment.
Keep your insulin in your carry-on when you travel, as luggage may be exposed to extreme temperatures.
If your insulin has been exposed to high temperatures (above 86 degrees Fahrenheit or 30 degrees Celsius) for more than a few hours, discard it, and start using fresh insulin.
If it has been exposed to temperatures above 100 degrees Fahrenheit (38 degrees Celsius)
at all , discard it immediately. This applies to pens, vials, and pump cartridges.
When exposing an insulin pump to warm weather, keep it out of direct sunlight, and place the pump and tubing in a cooling pouch if possible. Change the insulin cartridge and tubing more frequently when exposing the pump to prolonged warm temperatures. Keep the pump and tubing out of whirlpools, hot tubs, and saunas.
Missed Bolus Doses
Forgetting or neglecting to bolus for meals and snacks is a far too common problem. Given the dramatic blood sugar rise that can occur with even modest amounts of carbohydrates, missed boluses can result in extremely high blood sugar levels. Research has shown that for every two missed boluses per week, the A1c generally rises by a full percentage point.
Prevention: Some pumps, CGMs, pen apps, and blood glucose meters can be programmed with scheduled reminders to take a bolus. Users of the latest insulin pumps can avoid missing boluses by programming missed-bolus reminders at key times of day. Those who take injections might have an easier time remembering to bolus if they take blood sugars at each meal and snack time and keep written records. Those who consistently bolus
before eating are less likely to forget compared to those who bolus during or after meals. Some CGM users use the rise alert as a signal that they may have forgotten to dose for something they ate.
Let’s say you realize that you missed a bolus some time after you ate a meal or snack. Perhaps you received a reminder alert, or maybe you can hear your partner’s voice echoing in your ears:
“Did you take your bolus?!” What should you do? Cover the blood sugar that is now probably elevated and rocketing upward? Dose for the food your forgot to cover previously? Both? If you do both, you will double treat, dose for both the food and the blood sugar rise caused by the food, and will surely wind up low. Your best option is to ignore the blood sugar and dose for the food you ate previously but forgot to cover with a bolus. However, if you use a hybrid closed loop, the system may have already started increasing your basal insulin delivery, so you might need to take a bit less than your normal bolus for the carbs you missed.
Missed Basal Injections
Skipped basal injections are another potential cause of high blood sugar. Missing a meal dose is problematic in the short term. But missing a dose of basal insulin can lead to both high blood sugar over an extended period of time as well as the possibility of ketoacidosis.
Prevention: Plan to take your basal insulin at about the same time each day. If possible, combine it with another activity, such as brushing your teeth, taking oral medication, or eating a certain meal. Getting into a routine is the best way to ensure that you will not miss critical basal insulin injections. Consider setting alarms on your phone or using an app that provides reminders so that you never miss your basal insulin doses.
Poor Absorption
Poor absorption at the injection or infusion site can cause an insulin deficiency and elevated blood sugar. Remember, once insulin is injected or infused under the skin, it must absorb into the bloodstream in order to take effect. If the insulin pockets under the skin, it may never work. In some cases, the insulin may absorb much later than expected, resulting in a high blood sugar, followed by an unanticipated low. Site irritation or infection can also impair proper absorption.
Prevention: Be aware of the possible signs of site irritation and infection: redness, swelling, heat, itching, pain, and milky discharge (gross, I know). Avoid injecting sites that have any of these characteristics, and see a physician for treatment right away.
Just as you should rotate your tires to prevent uneven tread wear, you must rotate your injection and infusion (pump) sites to prevent uneven insulin absorption.
Injecting or infusing the same spots repeatedly can cause lipodystrophy, a breakdown or inflammation of the fat tissue below the skin.
When this happens, the skin can either dimple or become unusually hard and lumpy.
One of my patients calls these “happy spots” because they don’t hurt at all when giving a shot or inserting an infusion set.
The problem with happy spots is that they have much less blood flow than healthy tissue, and insulin does not absorb properly, if at all.
Avoid giving insulin into these areas.
Spreading your injection and infusion sites over a large area of skin should help prevent the development of lipodystrophy.
It’s best to not use the same exact injection or infusion sites twice in the same month.
And in the case of infusion sets, avoid prolonged use: two days is best, and three days is the maximum.
Try rotating injection and infusion sites in an organized fashion. Simply going from right side to left side repeatedly may result in the overuse of two specific sites. Instead, stay on one side of your body for several injections or site changes, moving just an inch or two (four to six centimeters) each time. Here is an example:
Left Side
1 2 3
Right Side
12 11 10
Left Side
6 5 4
Right Side
13 14 15
Left Side
7 8 9
Right Side
18 17 16
Once all of these sites are used, consider following a similar pattern on another body part, or start again on the same body part at site number 1.
Gaps in Coverage
An insulin program that has gaps in basal insulin coverage can lead to rising blood sugars, even in the absence of food. This applies to injected basal insulin (if the dose wears off before the next injection is taken) or pumped insulin (if the pump is suspended or disconnected for prolonged intervals).
Prevention: It is essential to understand the action profile of your injected insulin. If it lasts less than twenty-four hours, it will usually be necessary to take it more than once per day. If it lasts twenty-four hours, it is best to take it on a consistent schedule. Delaying it by more than a few hours can cause a major dip in the basal insulin level in your body.
When using an insulin pump, suspending is rarely necessary, unless you’re using a hybrid closed-loop system that suspends the pump automatically to help prevent hypoglycemia.
But if you do suspend manually, try not to leave the pump in suspend mode for more than an hour.
Similarly, when disconnecting at the infusion site (for exercise, bathing, water activities, physical intimacy), try to limit periods of disconnection to no more than an hour.
In fact, it is best to replace the missed basal insulin with a small bolus after reconnecting.
For example, if your basal rate is 0.6 units per hour and you disconnect for thirty minutes to go swimming, give a bolus of 0.3 units after reconnecting.
If you need to disconnect for longer than an hour, reconnect hourly and bolus to replace the basal insulin missed during the previous hour.
It is also reasonable to transition back to injection therapy for the day if you will need (or prefer) to spend large amounts of time disconnected.
A single dose of glargine, for example, can be given in the morning to replace most of the pump’s basal insulin for the next twenty-four hours.
The dose of glargine should be about 20 percent more than your pump’s total basal insulin for the day.
Insulin Pump Malfunction
Insulin pump therapy opens the door to elevated blood sugar in the event of a problem with insulin delivery, absorption, or action.
With no intermediate- or long-acting insulin in the body, pumpers rely on the delivery of basal insulin in the form of tiny pulses of rapid-acting insulin.
Any interruption in insulin delivery can result in a sharp rise in blood sugar and ketone production (described below) in as few as three hours after the last bit of insulin was infused.
This can be caused by any of the following
• tubing or infusion set clogs
• leaks where the cartridge connects to the tubing
• air pockets in the tubing
• dislodgement of the cannula or infusion set tube from the skin
• not connecting the tube completely at the infusion site
• improper or insufficient priming
• lack of insulin absorption or leakage at the infusion site
Prevention: Pump-related issues can be minimized by following correct infusion site-change, priming, and troubleshooting procedures.