• Blood glucose levels [ Time Frame: countinuasly ] [ Designated as safety issue: Yes ]
  

Device: 2 continuous glucose sensors, temperature sensor and insulin pump
2 continuous glucose sensors, temperature sensor and insulin pump

An open interventional data collection study in order to build a database to close the loop between glucose sensor and insulin pump.

background: The ultimate goal in diabetes treatment is to develop an autonomous insulin delivery system (artificial pancreas) capable of continuous glucose sensing, thereby mimicking the physiologic function of the islet beta cells and freeing the patient from the need for constant calculations of daily insulin and carbohydrates. Several prototypes of closed-loop system have been developed in recent years, based on different types of control algorithms, to establish the connection between the sensor and the insulin pump. Current research in the formulation of this type of subcutaneous closed-loop system still faces major challenges, therefore, there is a need for further study and evaluation.

Objectives:

1. To evaluate the lag time of the effect of subcutaneous insulin infusion on blood glucose levels by using continuous glucose sensor
2. To measure the insulin sensitivity as expressed by changes in blood glucose levels after s.c insulin infusion .
3. To evaluate real time sensor calibration algorithms based on the measured lag times .

Methods:

In the first phase of the study subjects will arrive to study visits fasting and will be connected to 2 continuous glucose sensors(S.C),temperature sensor (on skin) and insulin pump. Sensor initiation baseline data will be measured for the first 45 minutes.After baseline measurement subjects will receive standard meal and blood glucose levels will be measured from the continuous sensors and the vein. Short insulin analog will be delivered through pump and blood glucose levels will be recorded in the same way.

In the second phase of the study calibration algorithms which are based on the previously measured data will be evaluated and the study program for closing the loop will be tested in a simulation way in which the study team will be given a recommendation for insulin dose to be infused by the pump,using an open loop.In this part of the study,patients will be hospitalized for 24 hours and only the study team will decide about insulin dose to be infused.During the study blood glucose will be measured by glucometer in addition to continuous glucose sensor measurements and intravenous measurements.