Method and device for measurements in blood

Abstract

We present an optical probe arrangement that surrounds blood in a receptacle. It comprises LED's and light detector arranged to overcome the variations when the receptacle is translucent medical tubing and the like. Also, a signal processing algorithm is used to average signals from a plurality of light detectors, to further enhance results when measuring hematocrit. The invention makes it possible to add the feature of hematocrit measurement into dialysis system without major alterations to the dialysis machine or transport tubing.

1 - 3 . (canceled) 
     
     
         4 . Sensor device for the measuring of the density of a fluid flowing through a transparent tubing, said device comprising an elongate frame sized to fit around the tubing, said frame carrying a light beam emitter facing the tubing, and one or several sensor(s) also facing the vessel and so arranged that its or their sense sectors do not intersect the beam of the light source in the vessel or tubing. 
     
     
         5 . Sensor device according to  claim 4 , wherein the locations of the light source and sensor(s) respectively are separated lengthwise of the frame. 
     
     
         6 . Sensor device according to  claim 4 , wherein two sensors are arranged with their sensing directions perpendicular to the light beam. 
     
     
         7 . An optical probe arrangement that surrounds a fluid flowing through an elongate transparent tubing, said optical probe arrangement comprising a frame sized to surround said receptacle in part, said frame supporting at least two sets of light emitters and light detectors, each set comprising one light emitter and at least one detector, each set arranged to transilluminate the fluid at a preferred angle between said light emitter and said light detector—or detectors—of each set, where said angle is at least sufficient to avert direct light from said light emitter to said light detector, for the detection of constituents in said fluid. 
     
     
         8 . An optical probe arrangement according to  claim 7 , comprising four sets of light emitters and two or three light detectors in each set, wherein a light detector represents a detector incorporated in an adjacent set. 
     
     
         9 . An optical probe arrangement according to  claim 7 , wherein the light emitters are arranged as an array to encircle said elongated tubing at longitudinally one location around said tubing's circumference, and the light detectors are arranged to encircle the tubing at a different circumferential location. 
     
     
         10 . An optical probe arrangement according to  claim 7 , wherein a second array of light detectors are longitudinally located at a third location around said tubing's circumference, and the light detectors are arranged to encircle the tubing at that circumferential location. 
     
     
         11 . A method for processing signals from sensor devices as claimed in  claim 4 , including an amplifier for amplifying signals from the sensor devices, which comprises applying a signal processing algorithm on the signals from said sensor devices to calculate density. 
     
     
         12 . A method for processing signals from light detectors as claimed in  claim 11 , which comprises applying a signal processing algorithm on the signals from said light detectors, to detect said constituents. 
     
     
         13 . A method according to  claim 12 , which comprises applying a multi variable analysis of signals from all light detectors engaged in the signaling process. 
     
     
         14 . A sensor device as claimed in  claim 4 , wherein a third array of light sensors is longitudinally located at a fourth location around said tubing's circumference, and the light sensors are arranged to encircle the tubing at that circumferential location and an second array of light beam emitters is longitudinally located at a fifth location around said tubing's circumference, and the light sensors are arranged to encircle the tubing at that circumferential location. 
     
     
         15 . A method for processing signals from light sensors as claimed in  claim 14 , including an amplifier for amplifying signals from the light sensors, which comprises applying a signal processing algorithm on the signals from said light sensors, calculate density. 
     
     
         16 - 17 . (canceled) 
     
     
         18 . A method according to  claim 11 , wherein signals are processed in a time domain. 
     
     
         19 . A sensor device according to  claim 4 , further comprising a system to calculate density, and presenting the data to a display, and/or transferring data to another application. 
     
     
         20 . (canceled) 
     
     
         21 . Method for the measuring of the density of a fluid flowing in a tube, comprising directing of a light beam into the tube and that two sensors, are used that are opposed to each other. 
     
     
         22 . Method according to  claim 21 , characterized in that light beam and sensor beam(s) are perpendicular to each other. 
     
     
         23 . A sensor device as claimed in  claim 4 , characterized in that the measuring takes place in a tubing that is clamped in a holder with generally V-shaped recesses so that tube is given a substantially square cross section and that light emitters and sensors are arranged at the flat surfaces. 
     
     
         24 . A method for processing signals from light detectors as claimed in  claim 7 , including an amplifier for amplifying signals from the light detectors, which comprises applying a signal processing algorithm on the signals from said light detectors, to detect constituents in the fluid. 
     
     
         25 . A method according to  claim 24 , which comprises applying a multi variable analysis of signals from all light detectors engaged in the signaling process. 
     
     
         26 . An optical probe arrangement as claimed in  claim 7 , wherein a third array of light detectors is longitudinally located at a fourth location around said tubing's circumference, and the light detectors are arranged to encircle the tubing at that circumferential location, and an second array of light emitters longitudinally is located at a fifth location around said tubing's circumference, and the light detectors are arranged to encircle the tubing at that circumferential location. 
     
     
         27 . A method for processing signals from light detectors as claimed in  claim 26 , including an amplifier for amplifying signals from the light detectors, and which comprises applying a signal processing algorithm on the signals from said light detectors, to detect said constituents. 
     
     
         28 . A method according to  claim 15 , wherein signals are processed in a time domain. 
     
     
         29 . A method according to  claim 24 , wherein signals are processed in a time domain. 
     
     
         30 . A method according to  claim 27 , wherein signals are processed in a time domain.