Continuous IV Fluid Infusion System
Physical Location: For our project, calculation of the appropriate IV Fluid contents and calculations take place in the Raspberry Pi, which is basically simulating a medical device like Glytec’s Glucommander IV™, with wireless connectivity. Once the calculations are made, the appropriate concentrations of insulin are to be mixed into a fluid which passes through intravenous tubes that reach the patient’s veins. The medical device also contains a pouch of insulin, which must often be refilled by the medical personnel so that it does not run out.
Function: The continuous IV fluid infusion system delivers the appropriate insulin concentration into the patient’s blood over a continuous time. In cases of hypoglycemia (i.e. when the patient’s blood glucose levels have reached dangerously low), the system also automatically feeds dextrose (a kind of carbohydrate) through the intravenous tubes to normalize the patient’s blood glucose levels back to their basal glucose levels (80mg/dl). Thus, if either the patient decides to skip meals or the medical personnel is unable to deliver meals for the patient to eat, the continuous IV fluid infusion system performs the job of feeding the patient intravenously. When patients ‘disconnect IV’, the system directs its infuse insulin concentration to go to zero in order to stop the drip so that the patient can safely disconnect (i.e. in order to use the restroom). The last function is to compute how much of insulin reservoir is left, as insulin is being infused. Like all calculations in the continuous IV fluid infusion system, this one also takes place in the Raspberry Pi and then informs the medical personnel via Parse Cloud.
Coding:
To find the exact dosage of the infuse insulin as a function of the measured blood glucose level and the rate of change in glucose, I modified the Glucommander algorithm so that its suited for continuous (per 5 minute interval) time:
Infuse Insulin = (1/12) * Multiplier * (Glucose - 60)
We initialize the multiplier to be 0.02/12
If ( Glucose(current time) > 110 && (Glucose(current time))/(Glucose(5 minutes ago)) > 0.9875)
{ Increase Multiplier by (0.01/12)}
If ( Glucose(current time) > 110 && (Glucose(current time))/(Glucose(5 minutes ago))<= 0.9875)
{Use the same Multiplier}
Note that I divided by 12 often because unlike the original Glucommander algorithm which was to run at every hour, the modified algorithm runs every five minutes and there are 12 five minute intervals in an hour.
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Function: The continuous IV fluid infusion system delivers the appropriate insulin concentration into the patient’s blood over a continuous time. In cases of hypoglycemia (i.e. when the patient’s blood glucose levels have reached dangerously low), the system also automatically feeds dextrose (a kind of carbohydrate) through the intravenous tubes to normalize the patient’s blood glucose levels back to their basal glucose levels (80mg/dl). Thus, if either the patient decides to skip meals or the medical personnel is unable to deliver meals for the patient to eat, the continuous IV fluid infusion system performs the job of feeding the patient intravenously. When patients ‘disconnect IV’, the system directs its infuse insulin concentration to go to zero in order to stop the drip so that the patient can safely disconnect (i.e. in order to use the restroom). The last function is to compute how much of insulin reservoir is left, as insulin is being infused. Like all calculations in the continuous IV fluid infusion system, this one also takes place in the Raspberry Pi and then informs the medical personnel via Parse Cloud.
Coding:
To find the exact dosage of the infuse insulin as a function of the measured blood glucose level and the rate of change in glucose, I modified the Glucommander algorithm so that its suited for continuous (per 5 minute interval) time:
Infuse Insulin = (1/12) * Multiplier * (Glucose - 60)
We initialize the multiplier to be 0.02/12
If ( Glucose(current time) > 110 && (Glucose(current time))/(Glucose(5 minutes ago)) > 0.9875)
{ Increase Multiplier by (0.01/12)}
If ( Glucose(current time) > 110 && (Glucose(current time))/(Glucose(5 minutes ago))<= 0.9875)
{Use the same Multiplier}
Note that I divided by 12 often because unlike the original Glucommander algorithm which was to run at every hour, the modified algorithm runs every five minutes and there are 12 five minute intervals in an hour.
Back to introduction