Apparatus and methods for analyzing body fluid samples

A method of extracting and analyzing bodily fluids from a patient at the point of care for said patient comprising:

• establishing fluid communication between an analyte detection system, a sensor assembly, and a bodily fluid in said patient, wherein said sensor assembly comprises a first sensor;
• drawing from said patient a portion of said bodily fluid;
• monitoring a signal produced by said first sensor of the sensor assembly and detecting a change in the signal indicative of an arrival of said bodily fluid at said first sensor;
• ceasing to draw said bodily fluid from said patient in response to detecting said arrival of said bodily fluid at said first sensor;
• separating from said drawn portion a first component of said bodily fluid, while said analyte detection system and said sensor assembly remain in fluid communication with said patient;
• and
• with said analyte detection system, analyzing said first component to measure a concentration of an analyte.

Apparatus for monitoring a predetermined parameter of a patient's blood while infusing an infusion fluid into the patient, comprising:

• an infusion line and a catheter configured for insertion into a blood vessel of the patient;
• a reversible infusion pump connected between a source of an infusion fluid and the infusion line and catheter;
• a blood chemistry sensor assembly mounted in fluid communication with the infusion line and including a first sensor that provides a signal indicative of a predetermined parameter of any fluid present in the infusion line;
• a device operatively connected to provide one or more anti-clotting agents to at least a portion of said infusion line;
• a controller that operates the infusion pump in a forward direction, to pump the infusion fluid through the infusion line and catheter for infusion into the patient, and that intermittently interrupts its operating of the infusion pump in the forward direction to operate the infusion pump in a rearward direction, to draw a blood sample from the patient through the catheter and infusion line into sensing contact with the first sensor of the blood chemistry sensor assembly;
• wherein the controller further is configured to monitor the signal provided by the first sensor of the blood chemistry sensor assembly and to detect a change in the signal indicative of the arrival of the blood sample at the first sensor;
• wherein the controller, in response to detecting the arrival of the blood sample at the first sensor, ceases its operating of the infusion pump in the rearward direction;
• and wherein the signal produced by the first sensor provides an indication of a predetermined parameter of the patient's blood when the blood sample is in sensing contact with the first sensor.

A patient status monitoring system, said system comprising:

• a body fluid analyzer;
• a body fluid sensor assembly including a first sensor that provides a signal indicative of a predetermined parameter of any fluid present in the body fluid sensor assembly;
• a controller configured to monitor said signal from said body fluid sensor assembly and to detect a change in said signal indicative of an arrival of said body fluid sample at said first sensor;
• a fluid passageway configured to provide fluid communication among said body fluid analyzer, said body fluid sensor assembly, and a body fluid in a patient;
• said controller configured to be in communication with a data network;
• said data network configured to include at least one data file;
• said controller configured to access said at least one data file via said data network.

An analyte detection system comprising:

• a body fluid sensor assembly including a first sensor, the first sensor configured to provide information relating to a measurement of at least one analyte in a body fluid sample that is in sensing contact with the first sensor;
• a processor;
• and
• stored program instructions executable by said processor such that said system:
• (a) identifies, based on said measurement, one or more possible interferents to the measurement of said at least one analyte in the body fluid sample;
• (b) calculates a calibration which reduces error attributable to said one or more possible interferents;
• (c) applies the calibration to the measurement;
• and
• (d) estimates, based on the calibrated measurement, a concentration of said at least one analyte in the body fluid sample.

Apparatus for analyzing the composition of bodily fluid, said apparatus comprising:

• a first fluid passageway having a patient end which is configured to provide fluid communication with a bodily fluid within a patient;
• at least one pump coupled to said first fluid passageway, said at least one pump having an infusion mode in which said pump is operable to deliver infusion fluid to said patient through said patient end, and a sample draw mode in which said pump is operable to draw a sample of said bodily fluid from said patient through said patient end;
• a controller that is configured to operate said at least one pump in said infusion mode and in said sample draw mode;
• a spectroscopic analyte detection system accessible via said first fluid passageway such that said analyte detection system can receive at least one component of said drawn sample of bodily fluid, and determine a concentration of at least one analyte, said analyte detection system being spaced from said patient end of said first fluid passageway;
• a body fluid sensor assembly mounted in fluid communication with the first fluid passageway at or near said patient end and spaced from said analyte detection system, said body fluid sensor assembly including a first sensor configured to sense a property of the fluid within said first fluid passageway and to provide a signal indicative of said property;
• and
• wherein the controller is configured to monitor the signal provided by the first sensor of the body fluid sensor assembly and to detect a change in the signal indicative of an arrival of the body fluid at the first sensor.

A fluid handling and analysis system, said system comprising:

• a fluid transport network comprising at least a first fluid passageway, said fluid transport network including a patient end configured to maintain fluid communication with a bodily fluid in a patient;
• a sample analysis chamber and waste container, each accessible by said fluid transport network;
• a bodily fluid sensor assembly in fluid communication with said fluid transport network and including a first sensor that provides a signal indicative of a predetermined parameter of any fluid present in said first fluid passageway;
• a pump unit in operative engagement with said fluid transport network, said pump unit having an infusion mode in which said pump unit delivers an infusion fluid to said patient through said patient end, and a sample draw mode in which said pump unit draws a volume of said bodily fluid from said patient through said patient end, toward said sample analysis chamber;
• a spectroscopic fluid analyzer configured to analyze a sample of said of bodily fluid while said sample is in said sample analysis chamber, and determine a concentration of at least one analyte;
• said fluid transport network and said pump unit being configured to draw a volume of said bodily fluid from said patient, isolate a fraction of said bodily fluid from said volume, and pass said fraction to said sample analysis chamber and then to said waste container.

Apparatus for monitoring a predetermined parameter of a patient's body fluid while infusing an infusion fluid into the patient, comprising:

• an infusion line and a catheter configured for insertion into a blood vessel of the patient;
• a reversible infusion pump connected between a source of an infusion fluid and the infusion line and catheter;
• a body fluid sensor assembly mounted in fluid communication with -the infusion line and including a first sensor that provides a signal indicative of a parameter of any fluid present in the body fluid sensor assembly and further including a thermal device;
• a controller that operates the infusion pump in a forward direction, to pump the infusion fluid through the infusion line and catheter for infusion into the patient, and that intermittently interrupts its operating of the infusion pump in the forward direction to operate the infusion pump in a rearward direction, to draw a body fluid sample from the patient through the catheter and infusion line into sensing contact with the first sensor and the thermal device of the body fluid sensor assembly;
• wherein the controller further is configured to monitor the signal provided by the first sensor of the body fluid sensor assembly and to detect a change in the first signal indicative of an arrival of the body fluid sample at the first sensor;
• wherein the controller, in response to detecting the arrival of the body fluid sample at the first sensor, ceases its operating of the infusion pump in the rearward direction;
• wherein the signal produced by the first sensor provides an indication of a predetermined parameter of the patient's body fluid when the body fluid sample is in sensing contact with the first sensor;
• and
• wherein the controller is configured to communicate with the thermal device so as to regulate a temperature of the body fluid sample.