Automated Blood Sampler and Analyzer

• US 20100137778A1
• Filed: 12/02/2008
• Published: 06/03/2010
• Est. Priority Date: 12/02/2008
• Status: Active Grant

• Current Assignee: Cascade Metrix, LLC
• Original Assignee: Cascade Metrix, Inc.
• Inventors: Lloyd, Frank P. JR., Kunjan, Kislaya
• Granted Patent: US 8,348,844 B2
• Time in Patent Office: Days
• US Class Current: 604/6.150
• CPC Class Codes: A61B 5/14503 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors A61B5/1459, A61B5/1464, A61B5/1473, A61B5/1482, A61B5/14865 take precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14535 for measuring haematocrit
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: A61B 5/15003 for venous or arterial blood
• CPC Class Codes: A61B 5/150221 Valves
• CPC Class Codes: A61B 5/150229 Pumps for assisting the blood sampling
• CPC Class Codes: A61B 5/150358 Strips for collecting blood, e.g. absorbent optical reagent test strips G01N21/8483; chemical reagent test strips G01N33/4875, G01N33/52
• CPC Class Codes: A61B 5/150755 Blood sample preparation for further analysis, e.g. by separating blood components or by mixing
• CPC Class Codes: A61B 5/15087 short range, e.g. between console and disposable using implanted devices A61B5/150877
• CPC Class Codes: A61B 5/153 Devices specially adapted for taking samples of venous or arterial blood, e.g. with syringes
• CPC Class Codes: A61B 5/155 Devices specially adapted for continuous or multiple sampling, e.g. at predetermined intervals devices loaded with multiple lancets simultaneously A61B5/15146
• CPC Class Codes: A61B 5/412 Detecting or monitoring sepsis
• CPC Class Codes: A61M 2025/0042 Microcatheters, cannula or the like having outside diameters around 1 mm or less
• CPC Class Codes: A61M 25/0097 characterised by the hub connectors A61M39/10

Abstract

An automated blood sampler integratable with a glucose monitor comprises a catheter connected to a tube-set forming a single blood passageway; a clamp-on air-bubble sensor and a occlusion sensor externally attached to the tube set; a single peristaltic pump and two 3-way pinch valves attached to the tube set and control fluid flow. The sampler draws blood from a stationary patient, samples the blood for analytical measurement of blood parameters; after which the passageway is rinsed, the blood re-infused, and slow saline infusion prevents vein collapse. The cycle repeats at user or predefined intervals. In another preferred embodiment, blood is not re-infused, and only one 3-way pinch valve is used.

Claims

1. A system for automatically sampling blood from a patient, the system comprising:

an intravenous blood access catheter;

a tube-set connected to the catheter forming a single passageway for transporting and dispensing blood samples from a patient to the end of the passageway at a point of measurement, which is in sensing communication with an external blood parameter sensor;

a clamp-on air-bubble sensor and a occlusion sensor externally attached to the tube set;

two 3-way pinch valves spaced apart and externally attached to the tube set and a single peristaltic pump externally attached to the tube set between said pinch valves;

a rinse solution in fluid communication with both said pinch valves; and

a controller operatively connected to the peristaltic pump and said pinch valves;

the controller operates the peristaltic pump in forward and reverse mode, in forward mode, when the catheter is inserted in a patient'"'"'s bodily fluid vessel, the peristaltic pump draws blood from the patient to the point of measurement, once the external sensor measures the blood analyte, the controller controls the pinch valves, releasing rinse solution, rinsing said passageway;

after which the controller controls the pinch valves and operates the pump in reverse mode, re-infusing blood back into said patient.

2. The system in claim 1, wherein the system can be used for multiple automated diagnostic purposes, and integrated with a blood parameter monitor including a blood parameter sensor, wherein the blood parameter is selected from the group consisting of, glucose, lactate, electrolytes, cholesterol, urea, and blood gases;

wherein the blood parameter sensor is selected from the group consisting of, a test-strip, an electrochemical flow-through sensor, a mid-infrared spectroscopic flow-through sensor, a subcutaneous-implantable needle-type sensor inserted in said tube set in said passageway.

4. The system in claim 1, wherein the catheter is connected to the tube set via a specially designed luer connection, wherein the catheter comprises a patient end and a spaced apart end having a hub attached thereto;

the luer connection has a first end, a barbed end spaced apart a distance L, and a cylindrical core having an inside diameter D, which is tapered at the point of transition to the barbed end;

the luer first end is inserted inside the catheter hub;

L and D are sized to eliminate the dead volume normally present when blood enters said catheter hub;

6. The system in claim 4, including an aseptic quick release connection attached to the tube set proximal to the luer connection, comprising a female port with a self sealing diaphragm, a male connector with a non-coring needle, and a leak proof negligible dead volume.

7. The system in claim 6, wherein the rinse solution is normal saline.

8. The system in claim 7, wherein the system can be configured to draw blood and dispense samples to the point of measurement, at predefined or user defined intervals.

9. The system in claim 8, wherein the catheter is a small gage catheter having a size of 22 ga, and the tube set comprises micro tubing having a size of 0.5 mm ID.

10. The system in claim 9, wherein the length of tubing of the tube set ranges from 30 cm to 120 cm.

11. The system in claim 10, wherein the flow rate of the peristaltic pump ranges from 10 μ

L/min to 100 μ

L/min.

12. The system in claim 11, wherein the bodily fluid vessel is a vein;

and wherein after the saline rinse, the controller operates the pump in reverse mode to re-infuse the unused blood back into the patient;

after the blood is fully re-infused, the pump reduces speed to slowly infuse the patient with saline just enough to keep the vein open, preventing blood clotting;

during this time the system is in standby or therapeutic infusion mode until the next predefined or user actuated measurement.

13. The system in claim 12, wherein the blood parameter is blood glucose, and the blood parameter sensor is a blood glucose sensor;

and wherein the system includes a dextrose reservoir, an insulin reservoir, and a fluid selector manifold, for choosing the release of either saline, dextrose, or insulin;

wherein the manifold defaults to saline, but will release dextrose, if the glucose reading is low, or release insulin, if the glucose reading is high.

14. The system in claim 13, wherein blood is sampled from a bodily fluid vessel from the group comprising, a peripheral vein, an arterial line, or central venous line;

wherein the pinch valves are actuated using a motor selected from the group consisting of, solenoid motors and piezoelectric motors; and

wherein the system regulates the blood glucose using feedback control in a closed loop.

15. The system in claim 14, wherein an anticoagulant is added to the saline selected from the group consisting of regular heparin flush lock solution, and heparin of low-molecular weight variety.

16. The system in claim 14, wherein the passageway is covalently bonded with heparin.

3. A system for automatically sampling blood from a patient, the system comprising:

an intravenous blood access catheter;

a tube set connected to the catheter forming a single passageway for transporting and dispensing blood samples from a patient to the end of the passageway at a point of measurement;

a needle-type sensor inserted in said tube set at the point of measurement;

a clamp-on air-bubble sensor and an occlusion sensor externally attached to the tube set;

two 3-way pinch valves spaced apart and externally attached to the tube set and a single peristaltic pump externally attached to the tube set between said pinch valves;

a rinse solution in fluid communication with both said pinch valves; and

a controller operatively connected to the peristaltic pump and said pinch valves;

the controller operates the peristaltic pump in forward and reverse mode, in forward mode, when the catheter is inserted in a patient'"'"'s bodily fluid vessel, the peristaltic pump draws blood from the patient to the point of measurement, once the external sensor measures the blood analyte, the controller controls the pinch valves, releasing rinse solution, rinsing said passageway;

after which the controller controls the pinch valves and operates the pump in reverse mode, re-infusing blood back into said patient.

5. A specially designed luer connection, comprising:

a first end;

a barbed end spaced apart a distance L; and

a cylindrical core having an inside diameter D, which is tapered at the point of transition to the barbed end;

the luer first end is insertable inside a standard catheter hub;

D is reduced to minimize the dead volume; and

L is extended to eliminate the dead volume normally present when blood enters said catheter hub.

17. A system for automatically sampling blood from a patient, the system comprising:

an intravenous blood access catheter;

a tube set connected to the catheter forming a single passageway for transporting and dispensing blood samples from a patient to the end of the passageway at a point of measurement, which is in sensing communication with an external blood parameter sensor;

a clamp-on air-bubble sensor and a occlusion sensor externally attached to the tube set;

an in-line dilution sensor inserted in the passageway near the point of measurement;

two 3-way pinch valves spaced apart and externally attached to the tube set and a single peristaltic pump externally attached to the tube set between said pinch valves;

a rinse solution in fluid communication with both said pinch valves; and

a controller operatively connected to the peristaltic pump and said pinch valves;

the controller operates the peristaltic pump in forward and reverse mode, in forward mode, when the catheter is inserted in a patient'"'"'s vein, the peristaltic pump draws blood from the patient to the point of measurement, once the external sensor measures the blood analyte, the controller controls the pinch valves, releasing rinse solution, rinsing said passageway;

after which the controller controls the pinch valves and operates the pump in reverse mode, re-infusing blood back into said patient;

the system is integrated with a glucose monitor in a closed loop with feedback control, the glucose monitor comprising, a test strip based glucose meter, a plurality of test strips, and means, for presenting a test strip in sensing communication with a blood sample at the point of measurement, and for ejecting a test strip after measurement; and

the system includes a waste reservoir for collecting dispensed fluids and ejected test strips.

18. The system in claim 17, wherein upon a user activating the system, blood is drawn from the patient and dispensed to the point of measurement, until the blood is undiluted;

after which flow is reversed for a very short duration such that that any hanging blood drop is pulled back to prevent untimely introduction of a blood sample on a test strip at the point of measurement.

19. The system in claim 18, wherein the glucose strip is auto-calibrated, wherein the controller operates the pump in forward mode dispensing a single blood sample onto the test strip for measurement;

then the glucose meter measures the glucose concentration of the sample;

spontaneously displaying the reading on a patient monitor;

then the blood passageway is flushed with said rinse solution;

then the pump reverses direction to re-infuse the unused blood back into the patient;

after the blood is re-infused into the patient the pump reduces speed to slowly infuse the patient with the rinse solution just enough to keep the vein open, preventing blood clotting;

during which time the system is in standby until the next predefined or user actuated measurement.

20. The system in claim 19, wherein the means for presenting a test strip in sensing communication with a blood sample comprises an automated strip handler, comprising:

a resealable strip cartridge with opposed top and bottom ends, containing a plurality of strips stacked therein;

the cartridge is open at the bottom end, and a weight loaded at the top pushing strips out the bottom end;

a sliding strip feeding plate is capable of sliding to two positions, and comprises a projection with a size corresponding to the strip thickness;

the cartridge bottom end and the base top surface are slidably attached and aligned so that the weight pushes a test strip onto the base plate while it is in the first position;

three linear feed actuators; and

a gripper arm with clamping gripper pads;

the first linear actuator slides the strip feeding plate towards the meter to the second position at the point of measurement and a second motor causes the gripper arm to securely clamp the test strip;

the first linear actuator then slides the strip feeding plate back to position one;

the third actuator then moves the meter toward the test strip inserting the test strip inside the meter;

then the gripper pads releases the test strip, a blood sample is dispensed onto the test strip, and the meter measures the blood sample;

then the third actuator causes the meter to eject the strip while the gripper holds and later releases the strip before it falls into the waste reservoir.

21. The system in claim 20, wherein the three linear feed actuators are powered by miniature motors selected from the group comprising, DC motors, stepper motors, and piezoelectric motors.

22. An automated strip handler capable of storing a plurality of strips, being integrated with a blood sampling system, and capable of presenting a strip in sensing communication with a blood sample at a point of measurement and position a meter for the purpose of measuring said sample, the strip handler comprising:

a resealable strip cartridge with opposed top and bottom ends, containing a plurality of strips stacked there between;

the cartridge is open at the bottom end, and weight loaded at the top pushing strips out the bottom end;

a strip feeding plate, capable of sliding to two positions, having a slot that is etched on the top surface of the strip feeding plate conforming to the shape of the test strip;

the cartridge bottom end and the base top surface are slidably attached and aligned so that the weight pushes a test strip into the slot while the base is in the first position;

three linear feed actuators; and

a gripper arm with clamping gripper pads;

the first linear actuator slides the base towards the meter to the second position at the point of measurement and a second motor causes the gripper pads to securely clamp the test strip;

the first linear actuator then slides the base top surface back to position one;

the third actuator then moves the meter toward the test strip inserting the test strip inside the meter;

then the gripper pads release the test strip, a blood sample is dispensed onto the test strip, and the meter measures the blood sample;

then the third actuator causes the meter to eject the strip while the gripper pad holds and later releases the strip before it falls into the waste reservoir.

23. The automated strip handler in claim 22, wherein one gripper arm comprises a keyed slot, a roller pin, and a coiled spring restraining one end of the gripper arm;

the linear movement of one of the motors is converted to a gripping action in the vertical plane by moving the roller pin in the keyed slot within a gripper arm that is restrained by the coiled spring resistance.

24. The automated strip handler in claim 22, wherein the automated strip handler is capable of being integrated with a blood sampling and analyzing closed-looped system with feedback control.

25. A method for automatically sampling at least one parameter of blood from a patient, wherein the system with feedback control is integrated with a test strip based glucose monitor having a glucose meter, a plurality of test strips and means for presenting test strips in sensing communication with a blood sample, using said system comprising:

an intravenous blood access catheter;

a tube set connected to the catheter forming a single passageway for transporting and dispensing blood samples from a patient to the end of the passageway at a point of measurement, which is in sensing communication with an external blood parameter sensor;

a clamp-on air-bubble sensor and a occlusion sensor externally attached to the tube set;

two three-way pinch valves spaced apart and externally attached to the tube set and a single peristaltic pump externally attached to the tube set between said pinch valves;

a rinse solution in fluid communication with both said pinch valves; and

a controller operatively connected to the peristaltic pump and said pinch valves, the method comprising the steps of;

a, before connecting the catheter to the tube set prime the tube set by rinsing the tube set with saline to remove all air bubbles;

b, via an aseptic detachable connection connect the tube set to the catheter;

c, when the catheter is inserted in a patient'"'"'s vein, use the controller to operate the peristaltic pump in forward mode to draw blood from the patient to the point of measurement until the blood is undiluted;

d, use the controller to operate the peristaltic pump in reverse mode to pull back in the passageway any hanging blood droplet to prevent untimely suction of a blood sample by the test strip, thereby preventing said meter from giving an error message triggered by a premature blood sample dispensed on the one of said test strips;

e, activate the means for presenting test strips in sensing communication with a blood sample to present one of said test strips for measuring a blood sample;

f, use the controller to operate the peristaltic pump in forward mode to dispense a blood sample onto one of said test strips presented using the automatic strip feeder;

g, use the meter to perform the measurement,

h, discard the strip in the waste reservoir;

i, transmit the measured value to a display monitor through the communication protocol

j, use the controller to open one of said pinch valves to release saline to clear the passageway of blood;

k, use the controller to operate the peristaltic pump in reverse mode to re-infuse the unused blood back into the patient;

l, use the controller to reduce the speed of the pump to slowly infuse saline into the vein to keep vein open before next measurement;

m, repeat above steps at a predefined or user defined frequency of measurement.

26. A system for automatically sampling blood from a patient, the system comprising:

a flow-through sensor;

an intravenous blood access catheter;

a tube set comprising a single blood passageway and auxiliary treatment line for the flow-through sensor, said passageway comprising two ends, the first passageway end is connected to the catheter, the second passageway end is connected to the flow-through sensor;

a clamp-on air-bubble sensor and a occlusion sensor externally attached to the tube set;

three 3-way pinch valves spaced apart and externally attached to the tube set;

two peristaltic pumps externally attached to the tube set;

the first and second pinch valves are spaced apart between the first pump;

a calibrant and wash solution are connected to the treatment line;

the third pinch valve and second pump are externally attached to the treatment line for regulating release of the wash solution and calibrant;

a saline reservoir;

a dextrose reservoir, an insulin reservoir, and a fluid selector manifold are in fluid communication, the manifold is regulated by the first and second pinch valves;

a controller controls the pumps and valves;

when the catheter is inserted in a patient'"'"'s bodily fluid vessel, the controller controls the pumps and valves to draw blood from the patient to the flow-through sensor, after a bodily fluid parameter is measured in the flow-through sensor, the controller then controls the pumps and pinch valves, releasing rinse solution, first rinsing said passageway toward the flow-through sensor, then toward the patent;

after which the controller controls valves and pumps, releasing the wash solution, rinsing the flow-through sensor, then rinsing the flow-through sensor with the calibrant.

27. The system in claim 26, wherein the flow-through sensor is selected from the group comprising a flow-through sensor based on electrochemical technology, and a flow-through sensor based on mid-infrared spectroscopy;

wherein the catheter draws blood from a bodily fluid vessel from the group comprising, a peripheral vein, an arterial line, or from the central venous system; and

wherein an in-line dilution sensor is inserted in the tube-set near the flow-through sensor.

28. A method for automatically sampling and analyzing at least one parameter of blood from a patient using a system wherein the system comprises:

an intravenous blood access catheter;

a flow-through sensor;

a waste reservoir;

a silicone tube-set connected to the catheter forming a single blood passageway for transporting and dispensing blood samples from a patient to the end of said blood passageway through the flow-through sensor to the waste reservoir;

a rinse solution;

a dextrose reservoir, an insulin reservoir, and a fluid selector manifold for regulating the release of the rinse solution, the dextrose, and the insulin;

an in-line pressure sensor;

an in-line dilution sensor;

a wash solution;

a calibrant;

a first and second peristaltic pump and a plurality of pinch valves for controlling the flow of fluid in said blood passageway;

the method comprising the steps of;

a;

prime the system with saline before connecting the system to the patient by rinsing the tube-set with saline to remove all air bubbles eliminating the risk of air-embolism;

b;

perform two point calibration for the blood parameter, establishing the baseline and maximum measurement values;

c;

connect the system to the patient and draw blood wherein the first pump and plurality of pinch valves control the flow;

d;

measure the blood parameter in the flow-through sensor;

e;

rinse with saline the blood passageway to the flow-through sensor;

f;

wash the sensor using the wash solution;

g calibrate the system using the calibrant;

h;

repeat above steps at user-defined time intervals.

29. A system for automatically sampling blood from a patient, such that blood reinfusion is not required, the system comprising:

an intravenous blood access catheter;

a tube-set connected to the catheter forming a single passageway for transporting and dispensing blood samples from a patient to the end of the passageway at a point of measurement, the blood passageway being heparin coated and in sensing communication with an external blood parameter sensor;

a clamp-on air-bubble sensor and an occlusion sensor externally attached to the tube set;

a single three-way pinch valve and a single peristaltic pump externally attached to the tube set;

a rinse solution; and

a controller operatively connected to the peristaltic pump and the pinch valve;

the controller is configured to first operate the pump and valve to draw blood from the patient, dispensing a blood sample to the point of measurement;

then to operate the pump and valve to rinse said blood passageway to the waste.

30. The system in claim 29, wherein the system can be used for multiple automated diagnostic purposes, and integrated with a blood parameter monitor including a blood parameter sensor, wherein the blood parameter is selected from the group comprising:

glucose, lactate, electrolytes, cholesterol, urea, and blood gases, wherein the blood parameter sensor is selected from the group comprising, a test-strip based glucose meter, a flow-through-sensor, a mid-infrared spectroscopic flow-through sensor, a subcutaneous-implantable, needle-type sensor inserted in said tube set in said blood passageway.

31. The system in claim 30, including one quick aseptic connect and disconnect mechanism having a leak proof negligible dead volume connection for connecting the catheter to the tube set;

wherein the tubing is coated with heparin;

wherein the rinse solution is normal saline;

wherein there is a very short duration reverse pump flow cycle to pull back any hanging blood drop in the tube at the point of measurement to prevent premature suction by the test strip;

wherein the system can be configured to draw blood and dispense samples to the point of measurement, at predefined or user defined intervals.

32. The system in claim 31, wherein the catheter is a small gage catheter having a size of 22 ga, and the tube set comprises micro tubing having a size of 0.5 mm ID;

wherein the blood parameter is blood glucose, and the blood parameter sensor is a blood glucose sensor;

wherein blood is sampled from a blood vessel from the group comprising, a peripheral vein, an arterial line, or central venous line;

wherein the pinch valve is actuated using a motor from the group comprising, solenoid motors and piezoelectric motors;

wherein an in-line dilution sensor inserted in the passageway near the point of measurement, the in-line dilution sensor is based on impedance measurement of the blood hematocrit level.