Pump data interpretation using Carelink

Generating a report is a 4 step process:

1. Click on "Reports" in the left side menu
2. Select which report you would like to view - see below for recommendations
3. Select time period required - 14 days recommended
4. Click on "Generate Reports".

Select which reports you would like to view by clicking on each tile. We recommend:

1. Assessment & progress
2. Meal bolus wizard
3. Sensor & meter overview
4. Device settings snapshot
5. Adherence
6. Logbook

You can choose to view each one in turn, or select all of them at once to generate one long report, which is provided as a pdf file.

The number of glucose checks that you do will depend on whether you are fingerpricking for blood glucose, swiping your flash glucose sensor (FGS) or have a continuous glucose monitor (CGM).

Carelink records any glucose value entered into your pump as a "BG reading", regardless of whether this is blood glucose (BG) or a value taken from FGS and entered into your pump. Readings from CGM are displayed slightly differently and gives the time that the sensor is active each day, as well as the total time the sensor has been worn over the reporting period.

The number of BG readings is located on the left side of the "Adherence" page of the report:

Aim for 5-7 readings per day. If the average number of readings is less than 4, then there is not enough information to make any meaningful decisions; try to increase the number of glucose checks and repeat the upload in 2 weeks.

When you are using pump therapy, you should aim to administer bolus insulin for all meals, all snacks and to correct glucose readings which are above target. Therefore we recommend aiming for at least 7 boluses per day.

This information is also available in the adherence report, under “Bolus Wizard Events”. The average number per day is displayed at the bottom of the table - see below. There is also a break down of how many boluses are with food and how many are with correction.

If you are using a pump and CGM together in automode, the "Manual Bolus" column will detail how many additional boluses the system is delivering each day to try and get you into target.

We recommend set changes every 3 days or sooner if there is concern that insulin is not being delivered properly. If sets are kept in place for longer than this then the absorption of insulin from the site becomes less effective. This often leads to glucose readings above target. Remember to rotate your cannula sites. Repeated use of the same sites will lead to problems with insulin delivery.

You can review the number of days between set changes in the adherence report by looking at which days the cannula has been filled:

This is found at the top right hand corner of the "Sensor & Meter Overview" report.

The average daily insulin is also known as total daily dose of insulin (TDD). As children grow, they need more insulin. This is especially true around the time of puberty, when the body's hormones make an individual less sensitive to insulin.

Average daily insulin ratio

It is useful to look at the split between basal insulin (that which is delivered continuously by your pump), and bolus insulin (administered for food or as correction doses).

Usually between 30-40% is delivered as basal and around 60-70% as bolus. If you find the opposite, that the basal component is the higher %, then this can indicate too much reliance on basal insulin and that you or your child are forgetting some boluses.

Another potential indicator of missed boluses is if the average daily carbohydrate is lower than would be expected. The table below gives a useful guide which will apply to the majority of children:

If a correction dose is given, the glucose should fall into the target range (4-7 mmol/l) 2 hours after the correction dose is given. If this is not the case, then consider changing your device settings.
Here is an example of logbook entries showing corrections being ineffective, as the individual’s readings are remaining above target:

Things to note:

• The programmed correction factor is how much we would anticipate 1 unit of insulin would lower your child’s glucose by.
• Because small children have a low total daily dose of insulin, 1 extra unit would make a large change to their glucose. Small children therefore have a high degree of sensitivity to insulin and a high correction factor. For example, a correction factor of 8 means that 1 extra unit of insulin would be predicted to lower your child’s glucose by 8mmol/l.
• Older children have a higher total daily dose and so are less sensitive to 1 extra unit of insulin. A correction factor of 2 may be more appropriate, meaning that 1 extra unit of insulin would be anticipated to lower their glucose by 2 mmol/l.
• The required correction factor can be estimated using the sum: 100 divided by the total daily dose (TDD) of insulin. If the programmed correction factor is higher than the result of this sum, you may find that correction doses are not effective and therefore this should be adjusted.

The basal rate settings on you pump can be viewed on the "Device settings" report.

Consider:

• Number of basal patterns used - is another pattern required (e.g. for weekends or holidays)?
• When adjusting basal rate, adjust the rate 2 hours before the desired effect on blood glucose.
• Highest basal demands are at dawn (especially secondary school aged children) and dusk (especially primary school aged children).
• Make adjustments according to total daily dose of insulin - see table below.