There are many ways to measure blood glucose. The first one is to use a portable blood glucose meter to measure the blood glucose in the fingertips, which measures the blood glucose in the capillaries and usually differs by about 1 mmol/L compared to the venous blood. The second type is to measure the plasma glucose in the veins, which is the most accurate method to test the plasma glucose in the veins by drawing the blood in the veins with the machine. The third type is that blood glucose can also be checked when arterial blood gas analysis is drawn, but this is limited by the arterial blood gas testing machine, and usually if the blood glucose is too high over 30mmol/L it cannot be detected. The fourth is to use the method of dynamic blood glucose meter to monitor, which can use Medtronic’s instantaneous blood glucose monitor, which can be worn continuously for 14 days and display the current blood glucose value at every moment.