To be on the safe side
Setting of the sensor low glucose limit is the most important thing to prevent unexpected hypoglycemia. I started to use my continuous glucose monitoring system with low glucose limit set to 3.5 mmol/l (63 mg/dl) because I wanted my diabetes control to be as bests as possible. I considered that it is enough to add 0.4 mmol/l (7 mg/dl) as secure reserve to the value of 3.1 mmol/l (56 mg/dl), which is the limit value for hypoglycemia. I had experienced strong hypoglycemic episodes and tried to find out the reasons for them. I started to analyze and understand processes in my body and glucose monitoring system algorithms and have adjusted my low glucose limit to higher and higher values. I have described most of the factors that may create difference between blood and interstitial fluid glucose values in the previous chapters. They are listed below according to their importance:
There is a simple way how to measure if the low glucose limit is set properly to prevent frequent hypoglycemia. When interstitial fluid glucose value declines and reaches the low glucose limit set in the pump (alarm Low glucose), food should be supplied and blood glucose value measured several times around the time when the minimum of interstitial glucose value is reached. If the blood glucose reading is lower than 3.1 mmol/l (56 mg/dl), low glucose limit is set too low. This test needs to be repeated several times to make sure that reasonable value of the low glucose limit is found.
Currently my low glucose limit is set to 5.5 mmol/l (99 mg/dl) during normal days and 6 mmol/l (108 mg/dl) during days with extensive sport activities. High glucose limit is set to 9 mmol/l (162 mg/dl).