System for detecting the status of a vent associated with a fluid supply upstream of an infusion pump

Abstract

A system and method for determining whether the pressure in a fluid line upstream of an infusion pump is becoming lower as pumping draws fluid from the fluid line and fluid container due to a lack of proper venting. An initial pressure is sensed by an upstream pressure sensor at the start of an infusion. After a period of time, which may be determined either by monitoring infusion time or the number of pump cycles completed, a second pressure is sampled and compared to the initial pressure. Various analytical methods may be applied to the sensed pressures to determine upstream pressures or trends. Where an upstream pressure reading indicates a lack of proper venting, an alert signal is provided. Continuous monitoring may occur in which succeeding samples are compared to preceding samples to determine upstream pressures or trends.

1 . A system for detecting the status of a vent associated with a fluid supply upstream of an infusion pump, comprising: 
 a pressure sensor located upstream of an infusion pump, the pressure sensor configured to provide pressure signals representative of the pressure within a fluid line;    a processor configured to monitor a parameter representative of a status of the infusion pump and to sample the pressure signals received from the pressure sensor as a function of the status of the infusion pump, and, if the sampled signals indicate a negative pressure in the fluid line, to provide an alert.    
     
     
         2 . The system of  claim 1  wherein the infusion pump is a peristaltic pump and the monitored parameter is a value of the number of pump cycles the peristaltic pump has completed.  
     
     
         3 . The system of  claim 2  wherein the processor samples the signals received from the pressure sensor when the value of the monitored parameter exceeds a predetermined number of pump cycles.  
     
     
         4 . The system of  claim 2  wherein the processor periodically samples the signals received from the pressure sensor after a predetermined number of pump cycles have occurred.  
     
     
         5 . The system of  claim 4  wherein the predetermined number of pump cycles is three.  
     
     
         6 . The system of  claim 1 , wherein the negative pressure is indicative of a vent problem.  
     
     
         7 . A method of determining the status of a vent in a fluid line located upstream of a peristaltic infusion pump, the peristaltic infusion pump configured to pump fluid in a cyclical manner, the method comprising: 
 determining a value representative of the number of cycles that the have been completed by the infusion pump;    sampling signals provided by a pressure sensor configured to sense the pressure in a fluid line upstream of the infusion pump;    processing the signals to determine a value for the pressure in the upstream fluid line; and    providing an alert if the pressure value is negative.    
     
     
         8 . The method of  claim 7  wherein sampling occurs only when a predetermined number of pump cycles have been completed.  
     
     
         9 . The method of  claim 7  further comprising: 
 storing the value for the pressure in a memory;    sampling the signals after and predetermined number of cycles have been completed;    determining a second value for the pressure in the upstream fluid line;    comparing the second value for the pressure to the first value for the pressure; and    providing an alert signal if the second value is more negative than the first value.    
     
     
         10 . A system for detecting a change in pressure in an infusion line upstream of an infusion pump, comprising: 
 a pressure sensor located upstream of an infusion pump adjacent an upstream infusion line, the pressure sensor configured to provide pressure signals representative of the pressure within the upstream fluid line; and    a processor programmed to monitor a parameter representative of a status of an infusion of fluid into a patient, the processor also programmed to sample pressure signals received from the pressure sensor as a function of the status of the infusion, and to analyze the sampled signals to determine if the pressure in the upstream fluid line is decreasing.