Flow rate measurement and control of infusion devices

Abstract

An infusion apparatus includes a housing and a chamber configured to be connected to the housing. The apparatus further includes a weight sensor coupled to a load connector connected to the housing and an optical sensor disposed in the housing. The weight sensor is configured to generate a first signal based on a measured weight of the fluid container attached to the housing in a weight-bearing configuration. The optical sensor is configured to generate a second signal based on detecting drops of the fluid traversing the chamber. The apparatus also includes a flow control mechanism to control a flow rate of the fluid into an outlet channel. The apparatus includes one or more processing devices configured to perform operations including transmitting a control signal to the flow control mechanism to adjust the flow rate.

What is claimed is: 
     
         1 . A method of operating an infusion apparatus, the method comprising:
 receiving, by one or more processors, data indicative of detection of drops of a medical fluid dispensed from a fluid container;   receiving, by the one or more processors, data indicative of a weight of the fluid container;   computing, by the one or more processors, an estimated value of a flow rate of the medical fluid as a function of the data indicative of the detection of the drops of the medical fluid, the data indicative of the weight of the fluid container, and data indicative of fluid parameters of the medical fluid; and   operating, by the one or more processors, the infusion apparatus to adjust the flow rate of the medical fluid based on the estimated value of the flow rate.   
     
     
         2 . The method of  claim 1 , wherein:
 computing the estimated value of the flow rate of the medical fluid comprises computing an expected drop size based on the data indicative of the fluid parameters of the medical fluid.   
     
     
         3 . The method of  claim 1 , wherein:
 computing the estimated value of the flow rate of the medical fluid comprises computing the estimated value of the flow rate of the medical fluid based on a pump speed of a fluid pump in fluid communication with the fluid container.   
     
     
         4 . The method of  claim 1 , wherein the fluid parameters of the medical fluid comprises at least one of a specific gravity, a viscosity, or an opacity of the medical fluid. 
     
     
         5 . The method of  claim 1 , wherein:
 operating the infusion apparatus to adjust the flow rate of the medical fluid comprises operating the infusion apparatus to engage an outlet channel through which the medical fluid is dispensed.   
     
     
         6 . The method of  claim 5 , wherein:
 operating the infusion apparatus to engage the outlet channel comprises operating a fluid pump or an electronically controllable clamp positioned to engage the outlet channel.   
     
     
         7 . The method of  claim 1 , further comprising:
 receiving, by the one or more processors, a user selection indicative of the medical fluid.   
     
     
         8 . The method of  claim 1 , further comprising:
 accessing a representation of a medical fluid library containing data indicative of fluid parameters of a plurality of medical fluids to obtain the data indicative of the fluid parameters of the medical fluid.   
     
     
         9 . The method of  claim 1 , wherein:
 receiving the data indicative of the detection of the drops of the medical fluid comprises receiving, from a flow sensor, the data indicative of the detection of the drops of the medical fluid; and   receiving the data indicative of the weight of the fluid container comprises receiving, from a weight sensor, the data indicative of the weight of the fluid container.   
     
     
         10 . The method of  claim 9 , wherein computing the estimated value of the flow rate of the medical fluid comprises:
 identifying an error associated with the flow sensor or the weight sensor based on the data indicative of the detection of the drops of the medical fluid and the data indicative of the weight of the fluid container; and   computing the estimated value of the flow rate of the medical fluid based on only the data indicative of the detection of the drops of the medical fluid or based on only the data indicative of the weight of the fluid container.   
     
     
         11 . The method of  claim 9 , wherein the flow sensor comprises at least one of a drop sensor, an optical detector, an infrared detector, or an imaging device. 
     
     
         12 . The method of  claim 1 , wherein the data indicative of the detection of the drops of the medical fluid is further indicative of a quantity of the drops of the medical fluid. 
     
     
         13 . The method of  claim 1 , wherein computing the estimated value of the flow rate of the medical fluid comprises:
 computing a first estimated value of the flow rate of the medical fluid as a function of the data indicative of the detection of the drops of the medical fluid;   computing a second estimated value of the flow rate of the medical fluid as a function of the data indicative of the weight of the fluid container; and   computing the estimated value of the flow rate of the medical fluid as a function of the first estimated value and the second estimated value.   
     
     
         14 . The method of  claim 13 , wherein the estimated value of the flow rate of the medical fluid is a weighted average. 
     
     
         15 . The method of  claim 1 , wherein operating the infusion apparatus to adjust the flow rate of the medical fluid based on the estimated value of the flow rate comprises
 operating the infusion apparatus to adjust the flow rate of the medical fluid further based on a desired flow rate of the medical fluid.   
     
     
         16 . One or more non-transitory computer readable media storing instructions that are executable by one or more processors to perform operations, the operations comprising:
 receiving, by the one or more processors, data indicative of detection of drops of a medical fluid dispensed from a fluid container;   receiving, by the one or more processors, data indicative of a weight of the fluid container;   computing, by the one or more processors, an estimated value of a flow rate of the medical fluid as a function of the data indicative of the detection of the drops of the medical fluid, the data indicative of the weight of the fluid container, and data indicative of fluid parameters of the medical fluid; and   operating, by the one or more processors, an infusion apparatus to adjust the flow rate of the medical fluid based on the estimated value of the flow rate.   
     
     
         17 . The one or more non-transitory computer readable media of  claim 16 , wherein:
 computing the estimated value of the flow rate of the medical fluid comprises computing an expected drop size based on the data indicative of the fluid parameters of the medical fluid.   
     
     
         18 . The one or more non-transitory computer readable media of  claim 16 , wherein:
 computing the estimated value of the flow rate of the medical fluid comprises computing the estimated value of the flow rate of the medical fluid based on a pump speed of a fluid pump in fluid communication with the fluid container.   
     
     
         19 . The one or more non-transitory computer readable media of  claim 16 , wherein:
 accessing a representation of a medical fluid library containing data indicative of fluid parameters of a plurality of medical fluids to obtain the data indicative of the fluid parameters of the medical fluid, the fluid parameters of the plurality of medical fluids comprising at least one of a specific gravity, a viscosity, or an opacity.   
     
     
         20 . The one or more non-transitory computer readable media of  claim 16 , wherein computing the estimated value of the flow rate of the medical fluid comprises:
 computing a first estimated value of the flow rate of the medical fluid as a function of the data indicative of the detection of the drops of the medical fluid;   computing a second estimated value of the flow rate of the medical fluid as a function of the data indicative of the weight of the fluid container; and   
       computing a weighted average based on the first estimated value and the second estimated value, the weighted average corresponding to the estimated value of the flow rate of the medical fluid.