instructions for setting an OpenAPS

basal rate:

Adopt the basal rate from the previous pump therapy. Then after 2 weeks, the basal rate can  be optimized with an autotuner. But for this it is necessary that the carbohydrates are also entered during this time.

insulin carb ratio:

Default value for entered carbohydrates: grams of carbohydrates per 1 IU of insulin known from pump therapy.

Cut off values

Correction range during the day: 90-95 mg / dl and  at night: 85 mg / dl with an intermediate step of 88 mg / dl

Lowering before meals: 82 mg / dl

Interruption threshold: 80 mg / dl

ISF

Factor that expresses how much one unit of insulin lowers glucose in this hour. This varies from hour to hour. In the CGM pump control circuit in the loop system, this factor represents the amplifier.

Should be derived from pump therapy in a modified form.

 

insulin action time

Similar to short-acting insulin: ®Humalog, NovoRapid, Apidra: 3-4 h

Faster analog short-acting insulin: FIASP, Lyumjev: 2-3 h

Since the patient's insulin sensitivity varies from day to day, the insulin sensitivity is significantly higher after exercise and the insulin sensitivity is lower in the case of infections. The ISF can be indirectly changed with the insulin action time. If the insulin sensitivity is higher, the insulin action time is increased in 15 minute steps and vice versa if the insulin sensitivity is poor.

 

general limits in open artificial pancreas

maximum basal rate per hour: 4 times the highest basal rate increments in X IU / h

maximum bolus: e.g. 10 IU

 

other limits that have to be set in the system with microbolus

microbolus: at any time -always - with and without carbohydrates, automatic bolus application: 100% delivering by the system, so the amount of insulin will be completely independently delivered

basal rate booster: 4x

microbolus also with temporary overrides with  value of 120-140 mg / dl but not for values below the limit value

microbolus even with non-recent CGM values

 

FreeAPS factors

 

Retrospective correction time interval: 10 to 20 minutes. This means that every 10 minutes the system checks whether another insulin administration is necessary. A setting longer than 20 minutes is usually too weak and the glucose will spikes. With this function, the system can be used in the sense of an artificial pancreas - closed loop system - even without the input of carbohydrates.The prerequisite for the microbolus position is 100% autobolus delivery and permanent microbolus delivery.

Error Examples:

ISF too strong throughout the day, the glucose curve begins to fluctuate.ISF should be decreased by 1-2 mg/dl

ISF too weak from 1 to 6 a.m.

Why do low values occur at 8am and 8pm - ISF ??

 

ISF too strong 7 a.m. and 7 p.m.

ISF too weak from midnight to 6 a.m. and too strong from 7 a.m. to 8 a.m.

Post-meal CGM too high and then too low

Free APS with retrospective control without KH input - closed loop system but with administration of prandial insulin

Maximum dose of insulin per hour too low. Limit setting too low

Please adjust the factors until it works like this!