In addition to the glucose level, the sensor’s trend arrow also indicates the trend and rate of change in the next 15–30 minutes. As the change in blood sugar indicated by the trend arrow varies to some degree depending on the system, you should also familiarise yourself with the system in this regard.
In addition to the trend arrow, you should check the glucose trend for the last 15 minutes on the graph on your reading device or smartphone because there is a delay of a few minutes in the sensor reading.
Talk to your nurse or doctor about how you can use the trend arrows in different situations with the device you have access to.
Example of utilising trend arrows:
The insulin-to-carbohydrate ratio is 0.8 per 10 g of carbohydrates, i.e 0.8 units of bolus insulin for approximately 10 g of carbohydrates. The insulin sensitivity factor is 3, i.e. 1 unit of rapid-acting insulin lowers the blood sugar by approx. 3 mmol/l. The pre-meal glucose level is 9 mmol/l, with no physical exercise planned. The sensor’s trend arrow ↑ indicates a rising glucose level.
For a meal containing 40 g of carbohydrates, the person measures out 0.8 x 4 units of carbs + 1 unit for correction + 1 unit for predictive correction based on the trend arrow for a total of 5.2 units, rounded down to 5 units.