Optimising use of rate-of-change trend arrows for insulin dosing decisions using the FreeStyle Libre flash glucose monitoring system

Continuous glucose monitoring and flash glucose monitoring systems are increasingly used by people with diabetes on multiple daily injections of insulin and continuous subcutaneous insulin infusion. Along with real-time updates on current glucose levels, these technologies also use trend arrows to provide information on the direction and rate of change of glucose. Two systems, the Dexcom G5 and the FreeStyle Libre, have recently been approved for use without the need for adjunct capillary blood glucose, and there is a need for practical guidance for insulin dosing which incorporates rate of change in the insulin dosing algorithm. Here, we review the integration of rate of change trend arrow information into daily glucose management, including rapid-acting insulin dosing decisions. Based on the FreeStyle Libre flash glucose monitoring system, we also review a practical decision-support tool for actions to take when using trend arrows in conjunction with current glucose readings.