1. A closed loop catheter device comprising:
an elongate, flexible catheter body having a proximal end and a distal end;
a closed loop fluid flow circuit comprising a first lumen through which a fluid may flow into the catheter body and a second lumen through which fluid that has entered the catheter body through the first lumen may subsequently flow out of the catheter body;
a connector on the proximal end of the catheter body, said connector being having an inflow lumen which is connectable to and disconnectable from an inflow fluid source and an outflow lumen which is connectable and disconnectable from an outflow fluid receiver into which fluid may flow out of the first lumen; and,
a valving apparatus which prevents fluid from entering one of the first and second lumens when the connector is disconnected from at least the inflow source, such that fluid may then be evacuated from the closed loop circuit through the other of the first and second lumens without concurrent entry of make-up air or other fluid into the closed loop circuit.
2. A closed loop catheter device according to claim 1 further comprising a fluid reservoir formed on or in the catheter body in communication with the first and second lumens such that fluid thatflows into the catheterthrough the first lumen enters the reservoir and fluid that has entered the reservoir subsequently flows out of the second lumen.
3. A closed loop catheter device according to claim 2 wherein the reservoir comprises an expandable reservoir that expands when filled with fluid.
4. A closed loop catheter device according to claim 2 wherein the reservoir comprises a heat exchanger through which heat exchange fluid is circulated.
5. A closed loop catheter device according to claim 2 wherein the reservoir comprises an expandable heat exchanger which expands and contracts in response to the pressure of heat exchange fluid within the heat exchanger.
6. A closed loop catheter device according to claim 5 wherein the heat exchanger comprises a heat exchange balloon that is positioned on the catheter body, said heat exchange balloon having a deflated configuration of a first diameter and an inflated configuration of a second diameter.
7. A closed loop catheter device according to claim 6 wherein the heat exchange balloon comprises a plurality of lobes through which the heat exchange fluid circulates.
8. A closed loop catheter device according to claim 7 wherein at least some of the lobes are helically disposed about a central axis.
9. A closed loop catheter device according to claim 8 wherein the heat exchange balloon comprises a cental lobe and a plurality of outer lobes helically disposed about the central lobe.
10. A closed loop catheter device according to claim 4 wherein the catheter is insertable into the vasculature of a human or veterinary patient and advanceable to a position where the heat exchanger is positioned within a blood vessel whereby the heat exchanger is useable to exchange heat with blood flowing through that blood vessel.
11. A closed loop catheter device according to claim 1 further comprising a latch member for deterring inadvertent disconnection of the connector from the inflow source and outflow receiver.
12. A closed loop catheter device according to claim 1 further comprising a pressure indicator for indicating the fluid pressure within the closed loop circuit.
13. A closed loop catheter device according to claim 4 further comprising a pressure indicator for indicating the fluid pressure within the expandable reservoir.
14. A closed loop catheter device according to claim 13 wherein the expandable reservoir has a collapsed state and an expanded state and wherein the pressure indicator indicates when the pressure within the closed loop circuit is sufficiently low to cause the expandable reservoir to be in its collapsed state.
15. A closed loop catheter device according to claim 1 further comprising:
a distal catheter hub that is affixable to a body surface of a human or veterinary patient, said distal catheter hub having a proximal end, a distal end and a hollow bore extending therethrough, the catheter body being slidably disposed within the hollow bore of the distal catheter hub such that the catheter body may be advanced through said hollow bore and into the patient’s body, a generally tubular sterility barrier extending from the proximal end of the distal catheter hub and around an exteriorized portion of the catheter body to deter microbial contamination of that exteriorized portion of the catheter body.
16. A closed loop catheter device according to claim 15 further comprising:
a proximal catheter hub affixed to the proximal end of the catheter body, said generally tubular sterility barrier having a proximal end and a distal end, the distal end of the sterility barrier being attached to the distal catheter hub and the proximal end of the sterility barrier being affixed to the proximal catheter hub, the exteriorized portion of the catheter body comprising that portion of the catheter body that is between the proximal and distal catheter hubs and within the generally tubular sterility barrier.
17. A closed loop catheter device according to claim 15 wherein the generally tubular sterility barrier is substantially transparent such that the exteriorized portion of the catheter body may be visualized through the sterility barrier.
18. A closed loop catheter device according to claim 17 wherein graduated distance markings are formed on the exteriorized portion of the catheter body so that the operator may determine the approximate length of the catheter body that has been inserted into the patient’s body.
19. A closed loop catheter device according to claim 17 wherein the sterility barrier is flexible.
20. A closed loop catheter device according to claim 19 wherein the generally tubular sterility barrier is substantially formed of flexible plastic film.
21. A closed loop catheter device according to claim 1 further comprising a negative pressure apparatus connector for attaching a negative pressure apparatus to the lumen which remains open after the connector has been disconnected thereby facilitating the use of negative pressure to draw remaining fluid from the closed loop circuit.
22. A closed loop catheter system according to claim 21 wherein the negative pressure apparatus connector comprises a Luer connector which facilitates attachment of a syringe to the lumen that remains open such that the syringe may be used to draw remaining fluid from the closed circuit loop.
23. A closed loop catheter system according to claim 1 wherein the closure of the valving apparatus upon disconnection of the connector is substantially permanent so as to deter reuse of the catheter device.
24. A system for controlling the body temperature of a human or veterinary patient, said system comprising a closed loop catheter device according to claim 4, further in combination with:
an extracorporeal heat transfer fluid vessel which serves as both the inflow fluid source and the ouffow fluid receiver, said connector being connectable to and disconnectable from the extracorporeal heat transfer fluid vessel; such that heat transfer fluid may flow from the vessel;
heatercooler apparatus for alternately heating and cooling heat exchange fluid as it circulates through the extracorporeal heat transfer fluid vessel;
fluid propulsion apparatus for propelling the heated or cooled heat transfer fluid from the extracorporeal heat exchange fluid vessel, though the inflow lumen of the connector, through the first lumen of the catheter, through the heat exchanger, through the second lumen of the catheter, through the outflow lumen of the connector and back into the extracorporeal heat exchange fluid vessel;
body temperature sensing apparatus for sensing the patient’s body temperature;
a controller which receives i) a target temperature input and ii) a signal from the bodt temperature sensing apparatus indicating the patient’s body temperature, said controller being operative to control at least one of the heatercooler apparatus and fluid propulsion apparatus in response to at least one signal received from the body temperature sensing apparatus to raise or lowerthe patient’s bodytemperature to approximately the input target temperature.
25. A system according to claim 24 wherein the heatercooler apparatus comprises a housing, a heatingcooling element positioned within the housing and an opening through which the extracorporeal heat exchange fluid vessel may be inserted into the housing such that the heatingcooling element will heat or cool he heat transfer fluid contained within the extracorporeal heat transfer fluid vessel.
26. A system according to claim 24 comprising first and second body temperature sensors and wherein the controller receives the fist and second temperature signals from the first and second body temperature sensors and determines whether the difference between the first and second temperature signals exceeds a predetermined maximum acceptable temperature difference.
27. A system according to claim 26 wherein the controller causes the system to shut down when the difference between the first and second temperature signals exceeds the predetermined maximum acceptable temperature difference.
28. A system according to claim 26 wherein the controller causes an error signal to be emitted when the difference between the first and second temperature signals exceeds the predetermined maximum acceptable temperature difference.
29. A system according to claim 26 wherein the controller the controller selects one of the temperature signals as the driver signal if the difference between the first and the second temperature signal does not exceed a predetermined maximum amount.
30. A system according to claim 29 wherein the controller the controller selects the higher temperature signal as the driver signal.
31. A system according to claim 29 wherein the controllerthe controller selects the lower temperature signal as the driver signal.
32. A catheter device that is insertable into the body of a human or veterinary patient, said catheter device comprising:
a flexible catheter having a distal end and a proximal end, said catheter being insertable, distal end first, into the patient’s body such that a distal portion of the catheter resides within the patient’s body and a proximal portion of the catheter remains exteriorized; and,
a sterility barrier configured to substantially surround the exteriorized portion of the catheter so as to substantially prevent microbial contamination of the exteriorized portion of the catheter.
33. A catheter device according to claim 32 further comprising:
a distal catheter hub that is affixable to a body surface of the patient, said distal catheter hub having a proximal end, a distal end and a hollow bore extending therethrough, the catheter slidably disposed within the hollow bore of the distal catheter hub, the catheter being advanceable through said hollow bore and into the patient’s body such that the exteriorized proximal portion of the catheter extends out of the proximal end of the distal catheter hub; and,
a proximal catheter hub on the proximal end of the catheter body;
said sterility barrier comprising a generally tubular barrier that is affixed to and extends between the proximal catheter hub and the distal catheter hub so as to surround the exteriorized portion of the catheter.
34. A catheter device according to claim 32 wherein the sterility barrier is substantially transparent such that the exteriorized portion of the catheter body may be visualized through the sterility barrier.
35. A catheter device according to claim 34 wherein graduated distance markings are formed on the exteriorized portion of the catheter so that the operator may determine the approximate length of the catheter body that has been inserted into the patient’s body.
36. A catheter device according to claim 32 wherein the sterility barrier is flexible.
37. A catheter device according to claim 32 wherein the sterility barrier is substantially formed of flexible plastic film.
38. A catheter device according to claim 33 wherein the proximal catheter hub is also affixable to the patient’s body.
39. A catheter device according to claim 33 wherein the catheter further comprises:
a closed loop fluid flow circuit comprising a first lumen through which a fluid may flow into the catheter body and a second lumen through which fluid that has entered the catheter body through the first lumen may subsequently flow out of the catheter body.
40. A catheter device according to claim 39 wherein the catheter further comprises:
a connector on the proximal end of the catheter body, said connector being having an inflow lumen which is connectable to and diconnectable from an inflow fluid source and an outflow lumen which is connectable and disconnectable from an outflow fluid receiver into which fluid may flow out of the first lumen; and,
a valving apparatus which prevents fluid from entering one of the first and second lumens when the connector is disconnected from at least the inflow source, such that fluid may then be evacuated from the closed loop circuit through the other of the first and second lumens without concurrent entry of make-up air or other fluid into the closed loop circuit.
41. A catheter device according to claim 40 further comprising a fluid reservoir formed on or in the catheter body in communication with the first and second lumens such that fluid that flows into the catheter through the first lumen enters the reservoir and fluid that has entered the reservoir subsequently flows out of the second lumen.
42. A catheter device according to claim 41 wherein the reservoir comprises an expandable reservoir that enlarges when filled with fluid.
43. A catheter device according to claim 41 wherein the reservoir comprises a heat exchanger through which heat exchange fluid is circulated.
44. A catheter device according to claim 41 wherein the reservoir comprises a heat exchangerwhich expands and contracts in response to the pressure of heat exchange fluid within the heat exchanger.
45. A catheter device according to claim 43 wherein the heat exchanger comprises a heat exchange balloon that is positioned on the catheter body, said heat exchange balloon having a deflated configuration of a first diameter and an inflated configuration of a second diameter.
46. A catheter device according to claim 45 wherein the heat exchange balloon comprises a plurality of lobes through which the heat exchange fluid circulates.
47. A catheter device according to claim 46 wherein at least some of the lobes are helically disposed about a central axis.
48. A catheter device according to claim 47 wherein the heat exchange balloon comprises a cental lobe and a plurality of outer lobes helically disposed about the central lobe.
49. A catheter device according to claim 43 wherein the catheter is insertable into the vasculature of a human or veterinary patient and advanceable to a position where the heat exchanger is positioned within a blood vessel such that the heat exchanger is useable to exchange heat with blood flowing through that blood vessel.
50. A catheter device according to claim 40 further comprising a latch member for deterring inadvertent disconnection of the connector from the inflow source and outflow receiver.
51. A catheter device according to claim 40 further comprising a pressure indicator for indicating the fluid pressure within the closed loop circuit.
52. A catheter device according to claim 42 further comprising a pressure indicator for indicating the fluid pressure within the expandable reservoir.
53. A catheter device according to claim 52 wherein the expandable reservoir has a collapsed stated and an expanded state and wherein the pressure indicator indicates when the pressure within the closed loop circuit is sufficiently low to cause the compliant reservoir to be in its collapsed state.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for testing circuits, comprising:
providing a plurality of original test seeds;
generating a plurality of test patterns from the plurality of original test seeds, the generated test pattern plurality comprising a subset deterministic test pattern plurality;
loading the generated test pattern plurality into a circuit-under-test;
the circuit-under-test producing a plurality of test pattern responses from the generated test pattern plurality, one test pattern response for each of the generated test pattern plurality;
suppressing each of the plurality of test pattern responses not correlated with at least one of the deterministic test pattern plurality subset;
compacting a remainder of the plurality of test pattern responses not suppressed; and
outputting the compacted remainder of test pattern responses to a response monitor.
2. The method of claim 1, further comprising:
generating the plurality of test patterns from the plurality of original test seeds through a seed generation algorithm; and
using the seed generation algorithm to identify each of the subset deterministic test pattern plurality.
3. The method of claim 2, further comprising:
providing an input scan register configured to load the generated test pattern plurality into the circuit-under-test and a logic structure in communication with the circuit-under-test, the logic structure comprising a twist counter, a shift counter and a seed counter, the seed counter, the shift counter and the twist counter using the seed generation algorithm to generate the plurality of test patterns;
the twist counter and shift counter generating the subset deterministic test pattern plurality from the original test seeds by looping the original seeds through the input scan register.
4. The method of claim 3, wherein the plurality of original test seeds has a quantity value s, the input scan register has a length n, the seed counter is a log2 s bit seed counter, the shift counter is a log2 n bit shift counter, and the twist counter is a log2 2n bit twist counter, further comprising:
providing a response suppression logic component for suppressing the plurality of test pattern responses not correlated, the response suppression circuit having a number of inputs x; and
defining the number of inputs x by the formula x=log s+log 2n+log n+1.
5. The method of claim 3, wherein using the seed generation algorithm to generate the plurality of test patterns and identify each of the subset deterministic test pattern plurality comprises:
imposing an arbitrary ordering on the deterministic test pattern subset;
choosing a first starting seed for the deterministic test pattern subset;
performing 2n twists on the first starting seed;
if an original test seed on a logic twist cycle is compatible with a deterministic test pattern subset seed, marking a responsively generated test response as covered;
performing a 1-bit shift operation on the original test seeds;
repeating the last five steps of imposing, choosing, performing 2n twists, marking and performing the 1-bit shift operation until n shift operations are carried out;
if there are original test seeds not marked covered, choosing a first unmarked original test seed as a second starting seed and repeating the last six steps of imposing, choosing, performing 2n twists, marking, performing the 1-bit shift operation and repeating with the second starting seed; and
terminating the algorithm when all test seeds are marked covered.
6. A testing apparatus, comprising:
a memory comprising a plurality of original test seeds;
a logic structure in communication with a circuit-under-test and the memory device, the logic structure comprising a seed counter, a twist counter and a shift counter configured to use a seed generation algorithm to produce a plurality of test patterns from the original test seeds;
an input scan register in communication with the logic structure and configured to load the plurality of test patterns into the circuit-under-test; and
a response suppression circuit in communication with the circuit-under-test and the logic structure, the response suppression circuit configured to use the twist counter and the shift counter to:
generate a deterministic test pattern subset of the plurality of test patterns by looping the original test seeds through the input scan register, and
suppress each of a plurality of test pattern responses generated by the circuit-under-test in response to the generated test pattern plurality not correlated with at least one of the deterministic test pattern plurality subset; and
output a remainder of the plurality of test pattern responses not suppressed;
a compacter in communication with the response suppression circuit output configured to compress the response suppression circuit output; and
a response monitor configured to receive the compressed response suppression circuit output.
7. The apparatus of claim 6, wherein the logic structure is configured to use a seed generation algorithm to generate the plurality of test patterns from the plurality of original test seeds and identify each of the subset deterministic test pattern plurality.
8. The apparatus of claim 7, wherein the plurality of original test seeds has a quantity value s;
the input scan register has a length n;
the seed counter is a log2 s bit seed counter;
the shift counter is a log2 n bit shift counter;
the twist counter is a log2 2n bit twist counter; and
the response suppression circuit further comprises a test mode bit input and a logic component having a number of inputs x defined by the formula x=log s+log 2n+log n+1.
9. The apparatus of claim 8, wherein the response suppression circuit, the space compactor, the circuit-under-test and the logic structure are in circuit communication through a bus structure configured to arbitrate and thereby pass each of the remainder output to the space compactor responsive to response suppression circuit test suppression data.
10. The apparatus of claim 9, wherein the bus structure comprises a plurality of gates and the space compactor is connected to an output of each of the plurality of gates.
11. The apparatus of claim 10 wherein the memory is a buffer structure within a scan register or an external ROM.
12. The apparatus of claim 11 wherein the response suppression circuit is configured to use the twist counter and the shift counter to generate the deterministic test pattern subset of the plurality of test patterns by looping the original test seeds through the input scan register, and to suppress each of the plurality of test pattern responses not correlated with at least one of the deterministic test pattern plurality subset.
13. An article of manufacture comprising a computer readable medium having a computer readable program embodied in said medium, wherein the computer readable program, when executed on a computer, causes the computer to generate and apply a test pattern to a circuit-under-test by:
generating a plurality of test patterns from a plurality of original test seeds, the generated test pattern plurality comprising a subset deterministic test pattern plurality;
loading the generated test pattern plurality into the circuit-under-test;
suppressing each of a plurality of circuit-under-test test pattern responses not correlated with at least one of the deterministic test pattern plurality subset, the plurality of test pattern responses generated by the circuit-under-test from the generated test pattern plurality;
compacting a remainder of the plurality of test pattern responses not suppressed; and
outputting the compacted remainder of test pattern responses to a response monitor.
14. The article of manufacture of claim 13, wherein the computer readable program, when executed on a computer, further causes the computer to:
generate the plurality of test patterns from the plurality of original test seeds through a seed generation algorithm; and
use the seed generation algorithm to identify each of the subset deterministic test pattern plurality.
15. The article of manufacture of claim 14, wherein the computer readable program, when executed on a computer, further causes the computer to:
use a logic twist counter, a logic shift counter and a logic seed counter to generate the plurality of test patterns with a seed generation algorithm; and
use the twist counter and shift counter to generate the subset deterministic test pattern plurality from the original test seeds by looping the original seeds through an input scan register.
16. The article of manufacture of claim 15 wherein the computer readable program, when executed on a computer, further causes the computer to:
execute response suppression logic in suppressing the plurality of test pattern responses not correlated, the response suppression logic having a number of inputs x; and
define the number of inputs x by the formula x=log s+log 2n+log n+1, wherein the plurality of original test seeds has a quantity value s, the input scan register has a length n, the seed counter is a log2 s bit seed counter, the shift counter is a log2 n bit shift counter, and the twist counter is a log2 2n bit twist counter.
17. The article of manufacture of claim 16, wherein the computer readable program, when executed on a computer, further causes the computer to apply the seed generation algorithm to generate the plurality of test patterns and identify each of the subset deterministic test pattern plurality by:
imposing an arbitrary ordering on the deterministic test pattern subset;
choosing a first starting seed for the deterministic test pattern subset;
performing 2n twists on the first starting seed;
if an original test seed on a logic twist cycle is compatible with a deterministic test pattern subset seed, marking a responsively generated test response as covered;
performing a 1-bit shift operation on the original test seeds;
repeating the last five steps of imposing, choosing, performing 2n twists, marking and performing the 1-bit shift operation until n shift operations are carried out;
if there are original test seeds not marked covered, choosing a first unmarked original test seed as a second starting seed and repeating the last six steps of imposing, choosing, performing 2n twists, marking, performing the 1-bit shift operation and repeating with the second starting seed; and
terminating the algorithm when all test seeds are marked covered.