Insulin Adjustment

Once your diet and exercise program has become stabilized you will be in a position to consider adjusting insulin to produce sugars in the goal range. Before making any insulin adjustment you should have tested your blood sugar 4 times a day and once at 2-3 am during a minimum 4 day period. You should then calculate the average blood sugar at each time of day and compare those averages to your blood sugar goals. Flag any averages which are outside the goals and determine which outlier is the furthest from the goal. Then adjust the insulin dose that most likely affects that outlier blood sugar. For instance, if you are taking a shot of long-acting insulin at breakfast and bed and a shot of short-acting insulin with breakfast and dinner and your worst high blood sugar is at bedtime you should adjust your short-acting insulin before dinner. Adjust your insulin by increasing (or decreasing) the insulin by 10% rounding up or down as necessary. For example, if you had been taking 10 units of short-acting insulin before dinner you would increase it to 11. On the otherhand, if you were running low at bedtime you would decrease by 1 unit at least. On same insulin regime if you were high at breakfast but okay at 3 a.m. you would increase your bedtime long-acting; if you were high at lunch you would increase your short-acting before breakfast; if you were high at dinner you would increase your long-acting before breakfast. If you were high at 3 a.m. but okay at bed and breakfast you should probably not make any changes. An alternative to increasing your insulin would of course be decreasing your size of the most relevant meal i.e. the proceeding meal (or snack perhaps). You should not make any insulin adjustments if you have had any severe lows during the last several days or if your routine had been very unusual. Insulin adjustment is termed proactive. The intention is produce better blood sugars in the future rather than fixing them right now. See Fig1 and the analysis that follows below for an illustration of how you might record and analyze your blood sugars.

Fig 1 Blood Sugar Tabulation

Blood sugar targets: 5-8 before meals and bed, and more than 5 at 0300 hrs.

Example 1
	before b'fast	before lunch	before dinner	before bed	3 AM	Comments
Monday	8.9	13.4	4.2	11.4
Tuesday	12.1		8.8	9.8
Wednesday		10.2		7.6		at Canuck game
Thursday	6.8		7.9	7.2
Friday	9.4	14.6	11.6	10.8	14.5	spaghetti at mom's
Saturday	10.8	8.4	5.4	10.2
Sunday	8.1	10.9		8.9
Averages	9.4	11.5	7.6	9.4	14.5
Example 2
	before b'fast	before lunch	before dinner	before bed	3 AM	Comments
Monday	13.6	8.6	3.8	13.4
Tuesday	18.7	9.6	6.6	4.4
Wednesday	10.4	8.8	21.6	17.0		cinnamon bun at Max's
Thursday	15.8	19.7	4.3	10.3
Friday	9.1	12.7	7.1	13.3
Saturday	14.4	6.4	16.3	6.5
Sunday	12.9	8.4	4.9	2.8	14.0	swimming after dinner
Averages	13.6	10.6	9.2	9.7	14.0
Example 3
Monday	8.5	15.4	9.3	14.4
Tuesday	10.6	15.8	14.0	18.4
Wednesday	4.2	7.4	16.8	12.2
Thursday	18.6	16.4	15.8	5.3
Friday	3.5	11.1	2.9	12.8	4.8	training at Gold's
Saturday	3.8	4.1	12.1	13.0		training at Gold's
Sunday	2.2	12.8	5.3	7.7		training at Gold's
Averages	7.3	11.9	10.9	12.0	4.8
Example 4
Monday	5.7	2.4	12.8	11.4
Tuesday	11.6	3.9	14.9	6.9	5.0
Wednesday	4.9	3.4	20.6	14.6
Thursday	8.6	3.1	13.7	9.0
Friday	14.8	5.5	15.0	8.5
Saturday	5.5	5.1	9.8	6.1
Sunday	8.1	2.1	14.2	7.0		LO11am mowing yard
Averages	8.5	3.6	14.4	9.1	5.0

Analysis of Fig. 1

Example 1: There are no lows, the numbers are fairly consistent and the average that is furthest from desirable is at lunchtime. Appropriate actions could be either increase short acting insulin before breakfast or reduce the size/type of breakfast or mid-morning snack.

Example 2: There are no lows, the numbers are somewhat consistent, and the average that is most out of range is breakfast. Appropriate action would be to increase evening long acting insulin and test once or twice at 0300 hrs in the following week to make sure there are no lows at that time.

Example 3: Although none of the averages are out of range, the 3 consecutive breakfast lows following training the night before are dangerous. This was despite bedtime readings on the same nights being high. Appropriate action would be to decrease evening long acting on training nights.

Example 4: Lunch readings are consistently low. There was one mild low at 1100 hrs as well. Decrease breakfast short acting insulin or take a bigger breakfast or mid-morning snack.

"One-off" high blood sugars

The notion of "fixing the blood sugar right now" is best tackled by using a "sliding scale". This refers to taking extra short acting insulin at any one time of day to nominally lower your blood sugar into the goal range. For instance if it is breakfast time and your blood sugar is 12 (goal 4-7) and you normally take 8 units of short acting for breakfast you may decide to take an extra 2 units to do so. There is no perfect sliding scale for every person with diabetes. One very conservative approach to sliding scale follows:

"One-off" high blood sugars

Blood Sugar level	Extra Short Acting Insulin
< 3.5	-1 (snack or eat immediately)
3.5 - 8.0	0
8.1 - 10.0	+1
10.1 - 12.0	+2
12.1 - 14.0	+3
14.1 - 16.0	+4
etc.. Do not ever take more than 6 units of sliding scale unless you have been doing it for some time.

An alternative to taking extra insulin if your sugar is above your glycemic goal would be to do a short amount of exercise. It is fairly simple to learn how much exercise is required to bring your blood sugar down. For instance, on a stationary bicycle for 10 minutes may drop the blood sugar anywhere between 1-4 mmol?L. The virtue of exercise over sliding scale insulin is that you will never suffer from rebound phenomenon. Rebound phenomenon is where you take more insulin than is desirable, then go low and then the blood sugar bounces up as your body struggles to produce glucose. The body's tendency to prevent hypoglycemia is called counter-regulation and involves the secretion of a number of hormones including glucagon, adrenaline, cortisol and growth hormone. The rebound effects from counter-regulation may last for up to 24 hours after a severe low blood sugar.

"Rules" of Insulin Adjustment

Before you follow the rules below you must be testing frequently and following your meal and exercise plan closely. Generally only one insulin should be changed at a time. Increase or decrease insulin by 10% (or by1 unit if 10% is less than 1 unit). The rules below pertain to individuals taking regular short acting insulin. If you take ultra short acting insulin the rules are slightly different - these are appended later.

Lows

Lows always take precedence over highs. Even if you are high some or a lot of the time, If you have lows that are occurring consistently you must avoid them first. If lows are due to exercise, consider only changing an insulin dose (or increase meal or snack) for that specific day or time of day only.

• Breakfast lows: decrease evening long acting insulin
• Lunch lows: decrease breakfast short acting insulin (or increase breakfast or mid-morning snack)
• Dinner lows: decrease morning long acting insulin (or increase lunch or mid-afternoon snack)
• Bedtime lows: decrease dinner short-acting insulin (or increase dinner or evening snack)
• 0300 hrs lows: decrease evening long-acting insulin or take evening long acting insulin later (at bedtime if you are taking it before dinner)