System and method for detecting occlusion using flow sensor output
View Patent ↗A method and system for detecting an inclusion within an infusion system. The method includes monitoring an output signal of a flowrate sensor as fluid flows through an infusion system. The output signal is then converted with a noise reduction filter to obtain a filtered output signal. The filtered output signal is compared to a threshold value and an alarm is activated if the filtered output signal falls below a desired threshold, thereby indicating an occlusion within the infusion system.
1. A method of detecting an occlusion within an infusion system comprising:
monitoring an output signal from a flowrate sensor as fluid flows through a fluid pathway of the infusion system to a patient;
acquiring a baseline of the output signal of the flowrate sensor;
filtering the baseline with an averaging filter to calculate a baseline average;
calculating a threshold level as a percentage of the baseline average;
filtering the output signal with a noise reduction filter to obtain a filtered output signal; and
activating an alarm if the filtered output signal falls below the threshold level.
2. The method of claim 1 , which includes filtering the output signal with a backward averaging filter.
3. The method of claim 1 , which includes filtering the output signal with a ten second averaging filter.
4. The method of claim 1 , which includes continuously monitoring and filtering the output signal with the noise reduction filter.
5. The method of claim 1 , which includes acquiring the baseline of the output signal of the flowrate sensor while priming the infusion system.
6. The method of claim 1 , which includes calculating the standard deviation of the baseline average and calculating the threshold level by subtracting the standard deviation from the baseline average.
7. The method of claim 1 , which includes acquiring the baseline of the output signal of the flowrate sensor as the fluid is initially infused into the patient.
8. The method of claim 1 , which includes filtering the baseline with a backward averaging filter.
9. The method of claim 1 , which includes filtering the baseline with a ten second averaging filter.
10. The method of claim 1 , which includes monitoring an analog output signal from the flowrate sensor.
11. A system configured to perform the steps of claim 1 .
12. An infusion system, comprising:
a fluid pathway between a fluid source and a patient;
a flowrate sensor disposed along the fluid pathway, the flowrate sensor operable to produce an output signal;
a processing device in communication with and receiving the output signal from the flowrate sensor, the processing device configured to (i) acquire a baseline of the output signal of the flowrate sensor, (ii) filter the baseline with an averaging filter to calculate a baseline average, and (iii) calculate a threshold value as a percentage of the baseline average, and (iv) apply a noise reduction filter to the output signal to produce a filtered output signal; and
an alarm operable with the processing device to indicate when the filtered output signal falls below the predetermined threshold value.
13. The infusion system of claim 12 , wherein the flowrate sensor is configured to produce an analog output signal.
14. The infusion system of claim 12 , wherein at least one of the averaging filter and the noise reduction filter is of a type selected from the group consisting of: a backend averaging filter, a ten second averaging filter, a central averaging filter and a weighted averaging filter.