Method and system for infusing an osmotic solute into a patient and providing feedback control of the infusing rate
A patient intravenous (I.V.) infusion pump and biosensors, such as urine volume and sodium concentration sensors, are combined in an infusion system to infuse controlled amount of osmotic agent, such as hypertonic saline, into a blood vessel of a patient. A control subsystem is responsive to the biosensors output and configured to automatically adjust the infusion rate of the infusion pump based on said output. The resulting therapy increases urine output to resolve fluid overload and edema.
1 . A patient therapy system comprising:
a source of a solution of a blood compatible osmotic solute,
an infusion pump and an intravenous (I.V.) set for controlled delivery of the solution to the patient,
at least one biofeedback sensor, and
a controller responsive to the biofeedback signals from the sensor configured to adjust the pump based on the output of the at least on biofeedback sensor.
2 . The system of claim 1 in which the osmotic solute is hypertonic saline.
3 . The system of claim 1 in which the osmotic solute is urea.
4 . The system of claim 1 in which the at least one biosensor includes a urine volume sensor and a sodium concentration sensor.
5 . A method of controlling infusion of an osmotic solute comprising:
infusing the osmotic solute into a patient at a controlled infusion rate;
sensing a condition of the patient, wherein the condition is influenced by the infused osmotic solute, and
adjusting the infusion rated based on the sensed condition.
6 . A method as in claim 5 wherein the osmotic agent is hypertonic saline.
7 . A method as in claim 5 wherein the osmotic agent is urea.
8 . A method as in claim 5 further comprising sensing the sensed condition using at least one biosensor.
9 . A method as in claim 8 wherein the at least one biosensor includes a urine volume sensor and a sodium concentration sensor and the sensed condition includes at least one of urine volume of the patient and sodium concentration in the urine.
10 . A method of increasing a urine production of a patient comprising:
infusing an osmotic agent into a blood of the patient at a controlled infusion rate;
measuring urine output of the patient;
measuring a concentration of the osmotic agent in the urine output by the patient, and
automatically adjusting the controlled infusion rate based on the measured concentration of the osmotic agent in the urine.
11 . A method as in claim 10 further comprising automatically adjusting the controlled infusion rate based on a volume of the urine output.
12 . A method as in claim 10 wherein the volume of the urine output is measured over a predetermined period of time.
13 . A method as in claim 10 wherein the osmotic agent is hypertonic saline.
14 . A method as in claim 10 wherein the osmotic agent is urea.