Patient-specimen Identification System Using Stored Associated Numbers

Abstract

A patient-specimen identification system provides error-free identification of a specimen or sample from the time it is taken from a patient to the time when the results of the sample analysis are reported. Machine-readable labels are attached to the patient and to each container in which a sample or sub-sample may be contained. The machine-readable labels each contain a permanently encoded unique random number. When a sample is taken from the patient, the labels attached to the patient and the sample container are read and the two numbers are stored in an associated manner. Similarly, when portions of the sample are transferred to sub-sample containers, labels attached to the sample container and the sub-sample container are read and the two numbers are stored in an associated manner. The sub-samples are analyzed and the analysis results are associated with the number on the sub-sample container label. The analysis results are then correlated to the patient's identity and the analysis results and patient's identity are printed out in an associated manner.

Description

BACKGROUND OF THE INVENTION

The present invention relates to a system for analyzing samples from a bulk quantity and reliably reporting the analysis results. In particular, the present invention relates to a system and technique for error-free identification of results of specimen analysis with the patient from whom the specimen was taken.

The process now used in hospitals and laboratories for analysis of samples from patients is very complex. The process may require the handwritten transfer of the patient's name or number as many as twenty times between the time that the sample is taken and the time that the analysis results are reported to the physician. The large number of times the name or number has to be transferred greatly increases the chance for human error. In large hospitals, analysis of samples from many different patients is being performed at the same time. The chance for error in identifying the analysis results with the proper patient is unsatisfactorily high. An error may result because the sample was drawn from the wrong patient, because the sample container was incorrectly marked, because the label on the sample container was accidentally transposed during transit or processing, or because the label was misinterpreted. The results of an error may be fatal.

To solve this problem several systems have been proposed in which identification is carried from the patient to the final test results through a series of mechanical or electro-mechanical transfers of the identification data from the patient to a container and then from one container to another. For example, the system described in U.S. Pat. 3,618,836 by D. J. Bushnell et al. involves punching a coded number into a tag which is attached to the patient's wrist. When a blood or urine specimen is taken, the nurse or technician uses special equipment to punch the same coded number into a tag attached to the specimen container. At each subsequent transfer of a portion of the specimen from one container to another, the tag attached to the new container must be punched with the same coded number. Similar systems are shown in the following U.S. Pat. Nos.: 3,656,473 by Sodickson et al; 3,565,582 by R. R. Young; 3,526,125 by S. R. Gilford et al; 3,523,522 by E. C. Whitehead et al; 3,320,618 by B. L. Kuch et al; and 3,266,298 by E. C. Whitehead et al. These systems have several disadvantages. First, the hardware required for the mechanical or electro-mechanical transfer of the patient's number from one container to another is quite complex. Second, errors may still arise in the transfer of data from one container to another.

SUMMARY OF THE INVENTION

The present invention provides a method and system for reliably identifying the analysis results with the patient from whom the sample was taken. No manual, mechanical or electro-mechanical transfer of the patient's number from one container to another is performed.

Machine-readable labels are attached to the patient and to each container in which a sample or sub-sample may be contained. The machine-readable labels each contain an encoded random number. The patient's identity and the number encoded on the label attached to the patient are stored in an associated manner. When a sample is taken from the patient, the labels attached to the patient and the sample container are read and the two numbers are stored in an associated manner. Similarly, when portions of the sample are transferred to sub-sample containers, the labels attached to the sample container and the sub-sample container are read and the two numbers are stored in an associated manner. The sub-samples are analyzed and the label attached to the sub-sample container is read. The number of the sub-sample label is associated with the results of the analysis. Finally, the analysis results are correlated to the patient's identity and the analysis results and the patient's identity are recorded in an associated manner.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic representation of a preferred embodiment of the patient-specimen identification system of the present invention.

FIGS. 2, 2a-2c shows a machine-readable label for a patient-specimen identification system.

FIG. 3 shows the coding of the machine-readable labels of FIG. 2.

FIG. 4 shows the read head for reading the machine-readable labels of FIG. 2.

FIG. 5 shows a magnetic switch element of the read head of FIG. 4 when a hole is encountered in the coded label.

FIG. 6 shows a magnetic switch element of the read head of FIG. 4 when no hole is encountered in the coded label.

FIG. 7 is a schematic diagram of the electronics associated with the read head of FIG. 4.

FIG. 8 shows a portable console for reading and storing the wrist label number and the sample number.

FIG. 9 shows a transfer station in which the sample is transferred to various sub-sample containers.

FIG. 10 shows a transfer station console for reading the sample and sub-sample numbers.

FIG. 11 shows an automated test instrument for use in a clinical chemistry laboratory.

FIG. 12 shows a test station console for reading the sub-sample number.

FIG. 13 shows a data entry system for interfacing a Honeywell Diclan 240 clinical analyzer with a Honeywell H1602 computer.

FIG. 14 shows typical signals which are transmitted to the computer by the data entry system of FIG. 13.

FIG. 15 shows a reader and data entry means for use with a manual test station.

FIG. 16 is a table illustrating a preferred correlation technique.

FIG. 17 is a flow diagram.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In FIG. 1 is shown a schematic representation of a preferred embodiment of the patient-specimen identification system of the present invention. The system described in FIG. 1 is concerned with a clinical chemistry laboratory. It is to be understood, however, that the system may be used in other hospital laboratories, or in other systems in which samples are taken from a bulk quantity having an unique identity and in which identification of the analysis results with the bulk quantity must be made.

When a patient 10 enters the hospital he is given a wristband at the admission desk 11. Ordinarily the wristband contains his name, his hospital record number, and other information. To the wristband will be attached a machine-readable label 12 containing a unique random number x from a first set of random numbers X. To provide additional reliability, random number x may also be encoded on label 12 in a human-readable fashion. Random number x is a temporary number to be used as long as patient 10 is in the hospital. Label 12 is selected at random. Random number x and the patient's identity (for example his name, social security number or hospital record number) are entered into memory 13 by first data entry means 14. The patient's identity and random number x are stored in memory 13 in an associated manner.

When a test request for a particular patient reaches the laboratory, a technician takes several sample containers 15, the test request, and several sample container labels 16 to the patient's room. If a blood sample is requested, sample container 15 may comprise a blood drawing container such as a Becton-Dickenson Vacutainer. Sample container label 16 may be permanently attached to sample container 15 or may be capable of being attached and removed from sample container 15 at will. Sample container label 16 is encoded with a machine-readable unique random number y from a second set of random numbers Y. Random number y may also be displayed on sample container label 16 in a human readable number.

In the patient's room the technician takes a fluid or tissue sample from patient 10 and places it in sample container 15. Sample container 15 will have a sample container label 16 attached to it before the sample is placed in sample container 15, or the technician will attach sample container label 16 to sample container 15 at the time that the sample is taken.

By means of first reader 17, the technician then reads label 12 and sample container label 16. First reader 17 is a portable device and may be incorporated as part of the technician's test tube tray. Random number x and random number y are stored in a temporary portable memory 20, which may also be a part of the technician's tray. Random number x and random number y are stored in temporary memory 20 in an associated manner. Additional data may also be stored with the associated pair in temporary memory 20. For example, it is often useful to record the time at which the sample was taken.

When the technician has finished her rounds, she returns to the laboratory and connects temporary memory 20 to second data entry means 21. Random number x and random number y and associated data are transferred from temporary memory 20 to memory 13 by data entry means 21. Random numbers x and y are stored in memory 13 in an associated manner.

In the laboratory, the sample is split into several smaller samples, each of which will go to a test instrument for analysis. Sample transfer station 22 divides the sample into sub-samples and transfers the sub-samples to various sub-sample containers 23. Attached to each sub-sample container is a sub-sample container label 24. Encoded on each sub-sample container label 24 is a unique random number z from a third set of random numbers Z. Second reader 25 reads sample container label 16 and sub-sample container label 24 at the time of transfer of the sample to sub-sample containers. Random numbers y and z are directed by reader 25 to third data entry means 26. Random numbers y and z are then directed by third data entry means 26 to memory 13, where they are stored in an associated manner.

The sub-sample containers are then taken to an analyzer 27, which may comprise an automated test instrument or a human operated tester. Sub-sample container label 24 is read by third reader 30 and random number z is directed to fourth data entry means 31. The sub-sample is analyzed by analyzer 27 and the test results are directed to fourth data entry means 31. Random number z and the corresponding test results are directed by fourth data entry means 31 to memory 13 in an associated manner.

At this point in the system, all of the necessary information has been entered into memory 13. Four associated pairs of identification information exist in memory 13 for each test result. These are: the patient's identity and random number x which were entered at the time od admission; random number x and random number y, which were read and temporarily stored when a sample was taken from the patient and which were later entered into memory 13; random number y and random number z, which were entered at the time of division of the sample into sub-samples; and random number z and the test results, which were entered at the time of the analysis by analyzer 27. Logic means 32 takes the four associated pairs and correlates the test results with the patient's identity. Logic means 32 then directs printer 33 to print out the patient's identity and the test results in an associated manner so that they may be used for diagnosis.

Logic and Memory

The use of a general purpose digital computer as logic means 32 and memory 13, is particularly advantageous in the present patient-specimen identification system. Many hospitals already utilize a digital computer for other purposes such as billing and accounting. By appropriate hardware and software integration, a digital computer may be time shared between the patient-specimen identification system and other, unrelated uses.

In one successful embodiment of the present invention, logic means 32 and memory 13 comprise a Honeywell H1602 computer. For the purpose of further discussion, this preferred embodiment of the present invention using the H1602 computer will be specifically described. It should be understood, however, that other digital computers or any dedicated logic/memory unit may be used.

Labels

FIG. 2 shows preferred embodiments of machine-readable labels for a patient-specimen identification system. For the purpose of discussion, the coding on the labels comprises a fourteen hole pattern representing four octal digits, two label identification bits, and two parity bits, as shown in FIG. 3. The readers described in later sections of the specification are shown as being adapted to read the fourteen hole pattern. It should be understood, however, that the present invention is in no way limited to a particular type of label or a particular coding system.

FIG. 2a shows one preferred embodiment of the label which is attached to the patient. A flexible band 40 is adapted to be attached to the patient's wrist. Flexible band 40 contains written information about the patient, such as his name, social security number, and the like. Patient label 41 is a slotted circular member, preferably of molded plastic, which slides over a flexible band 40. Since label 41 slides over the flexible band, it may be reused after the patient has left the hospital.

Each patient label 41 is uniquely coded with a fourteen position hole pattern and a read trigger pin. The fourteen hole pattern represents four octal digits and two parity bits, as shown in FIG. 3. The read trigger pin is a different size or shape from that of the holes of the hole pattern. The read trigger pin activates the reader so that the machine-readable number contained in the fourteen hole pattern is read. The use of a read trigger pin also insures the label is aligned properly with respect to the reader.

FIG. 2b shows a machine-readable label which may be used with a Vacutainer or test tube. Label 42 is a circular collar which fits around the Vacutainer 43. As with patient label 41, sample label 42 has a fourteen hole pattern encoded in one surface.

FIG. 2c shows a sub-sample label 44 which may be attached to a sub-sample container 45 such as a test cup for an automated instrument. Sub-sample label 44 is a toroidal body which press fits over the mouth of the test cup 45. A fourteen hole pattern is encoded on the label.

It is highly desirable to use a single type of read head which is capable of reading all three types of labels. This allows the portable console and the transfer station console to have only one read head each rather than two. By the use of a single read head the mechanical and electrical hardware of the portable console and the transfer station console is significantly reduced.

While it is desirable to use a single type of read head to read all three types of labels, it is necessary that the reader be able to distinguish between the different kinds of labels. Although this identification feature can be achieved in many ways, one advantageous way of distinguishing the three types of labels utilizes the two label identification bits of the fourteen hole pattern. For example, a patient label may be identified by having both bits being a digital "1". The Vacutainer label is identified by having the first bit be a digital 1 and the second bit be a digital "0". The test cup label is identified by having the first bit be a digital 0 and the second bit be a digital 1.

In a preferred embodiment, the labels contain a human-readable representation of the machine-readable number. This makes manual back-up procedures possible. For example, the Vacutainer (sample) number can be written on the test request and the test cup (sub-sample) number can be written on the laboratory work lists or in data books. In addition, the use of a human-readable number allows easy location of particular samples to repeat tests.

READERS

The read head for each label type utilizes fourteen sensing elements for sensing the presence or absence of a hole in the coded label. In one preferred embodiment, the sensing elements are magnetic switch elements similar to those shown in FIG. 4. When there is a hole in the coded label, closure spring 50 maintains flux closure block 51 in contact with ferrite C core 52. When drive core winding 53 is pulsed the magnetic closure through sense winding 54 generates a signal indicating a digital 1. As shown in FIG. 5, most of the magnetic flux passes through sesse winding 54 when flux closure block 51 is in contact with ferrite C core 52.

When push rod 55 encounters no hole in the coded label, push rod 55 pushes flux closure block 51 away from ferrite C core 52 thus opening the flux closure path. As shown in FIG. 6, in the open position very little magnetic flux passes through sensing winding 54 when a current pulse is applied to drive winding 53. The signal produced when the push rod encounters no hole is designated a digital 0.

READ ELECTRONICS

FIG. 7 shows the electronics used to sequence the read head having magnetic switch elements as it reads the precoded pattern stored on the labels. When the read head and the label are brought into contact, the read trigger pin causes switch S1 to close. Oscillator control 60, which may comprise a flip flop, starts oscillator 61. Oscillator 61 drives counter 62 and timing circuit 63. Counter 62 counts from 1 to 8. The output of counter 62 is decoded by decoder 64, which sequentially addresses transistors Q1 through Q7. As each transistor turns on, it supplies current to two series connected drive coils mounted in the read head. This current produces a voltage on the sense winding whose amplitude is proportional to the distance between the C core and the closure block. For example, the output of decoder 64 which is associated with the count of 1 turns on transistor Q1. When transistor Q1 turns on, current flows through the drive line to drive coils 1A and 1B which are connected to two different C cores. Signals then appear on the secondary windings S1A and S1B. If the ferrite closure block is pressed closely to the C core, the signal is large enough to overcome the diode drop and appear at the input to a sense amplifier. The signals from the sense windings are amplified by sense amplifiers A or B, depending upon which one is strobed by timing circuit 63. When sense amplifier A is strobed, the signals from sense coils S1A through S7A are read out sequentially. This produces the first seven bits. When counter 62 begins counting from 1 to 8 a second time, sense amplifier B is strobed. Coil drive transistors Q1 through Q7 are again sequentially addressed. The signals from sense windings S1B through S7B are amplified by sense amplifier B and constitute bits 8-14.

The signals from sense amplifiers A and B are directed to OR gate 65. The fourteen bit output signal from OR gate 65 is directed to a temporary memory or a data entry device. In addition, bits 3-6 and 8-13 are directed into 12 bit shift register 66. Label identification bits 1 and 2 and parity bits 7 and 14 are not stored in shift register 66. The stored bits are then decoded and displayed by display means 67. When the read operation is complete, timing circuit 63 provides a signal to oscillator control 60, which turns off oscillator 61.

Portable Console

FIG. 8 shows a portable console for reading and storing the wrist label number x and the sample number y. The portable console is incorporated in the technician's tray which is carried by the technician to the patient's room when samples are to be taken. A hand held wrist label reader 101 is used to read the number encoded on the patient's wrist label and the number encoded on the Vacutainer label.

Read electronics similar to those shown in FIG. 7 are included on the console. The read electronics are powered by a battery contained in the console. In order to minimize the power requirements on the battery, two power levels are maintained. A continuous power level is used for memory maintenance. The temporary memory contained in the portable console may, for example, be a semiconductor memory. It is therefore necessary to maintain continuous power to the memory so that the information will not be lost. The second power level is used for the read operation. Power is supplied to the read electronics only during the read operation. The read trigger pin triggers a switch which turns the power on when the read head and the label are brought into contact.

When the technician enters the patient's room, she removes the Vacutainer from a first rack 110 of her tray. As she fills each Vacutainer, she places it in a second rack 111. After the required number of Vacutainers have been filled, the patient's wrist label is read by bringing label reader 101 in contact with the patient's wrist label, causing the wrist label number to be transferred to the portable memory.

After the patient's wrist label is read, the label on each of the Vacutainers in rack 111 is read and transferred to the portable memory. Random number x is stored in a buffer memory which is read each time a Vacutainer label is read. These two numbers are then stored in the temporary memory. This arrangement avoids having to read the patient's wrist label each time that a Vacutainer label is read. After each of the Vacutainer labels have been read, the Vacutainers from rack 111 are transferred to rack 112.

The portable console optionally may contain display means for visually displaying random numbers x and y as read by the reader. This allows the technician an opportunity to visually perform a check to determine if the numbers were correctly read.

When the technician returns to the laboratory, data is transferred from the temporary memory into memory 13. An electrical connection between memory 13 and the portable console may be made through data transfer terminal 113. When the data has been entered into memory 13 and properly stored, a signal is sent to the portable console which causes data transfer indicator 114 to indicate that the data has been properly received.

It is often desirable to record additional information along with the wrist label number and the Vacutainer numbers. In particular, it is often useful to have a record of the time at which the sample was taken. In one preferred embodiment of the present invention, therefore, an oscillator and counter are provided inside of the portable console. When the technician is about to leave to take samples from patients, she makes electrical contact with memory 13 and logic means 32 through data transfer terminal 113. The count on the counter as well as the actual time from the clock in logic means 32 are stored in memory 13. In one embodiment the count is zero and the oscillator is started by making electrical contact. In another embodiment, the oscillator is free running and the count on the counter is some random number r. Each time a Vacutainer label is read, the count on the counter is stored in the temporary memory along with the associated random numbers x and y. From this information the time that the sample was taken can be obtained. In the embodiment in which the initial count was zero, the actual time of taking the sample is the initial time when the technician made electrical contact to the memory plus the count times the time increment between counts of the oscillator. In the second embodiment in which the initial count was random number r, the actual time of taking the samples is the original time stored plus the stored count minus the original count times the time increment between counts of the oscillator.

TRANSFER STATION

In FIG. 9 is shown a transfer station in which blood from the Vacutainers is transferred to various test cups. As shown in FIG. 9, each Vacutainer is arranged in a column with the test cups. Blood is transferred from a Vacutainer to each of the test cups in the column. This transfer may be done manually or by automated techniques. The read head sequentially reads the Vacutainer label and then each of the test cup labels in a column. The read head may be hand held, as shown in FIG. 9, or may be incorporated in automatic apparatus.

FIG. 10 shows a transfer station console. The apparatus and operation of the transfer station console is similar to the portable console. Similar numerals have therefore been used to designate similar elements. Since it is desirable to avoid reading the Vacutainer label each time one of the test cup labels is read, a buffer memory is provided to store the Vacutainer number while each one of the test cup labels is read. Each time a test cup label is read the buffer memory containing the Vacutainer number is also read. The associated pair of numbers is sent to memory 13. Data received indicator 114 indicates that the associated pair has been received and properly stored in memory 13.

AUTOMATED TEST STATION

One highly advantageous automated test instrument for use in a clinical chemistry laboratory is the Honeywell Diclan 240 clinical analyzer. A patient-specimen indentification system utilizing the Diclan will therefore be described. It should be understood, however, that other automated test instruments may also be used.

FIG. 11 shows a Diclan 240 clinical analyzer. Test cups containing sub-samples are received from the transfer station and placed in a sample chain 150. As sample chain 150 is sequentially advanced, sub-sample extractor 155 removes the contents of each test cup and transfers the contents to a Diclan test cup. The Diclan test cups are arranged in a test chain. The first sub-sample extracted is placed in the first Diclan test cup, and so on. Thus the order of the sub-samples is maintained throughout analysis.

Test cup label reader 160 reads the test cup labels in the same order that the samples are extracted. In other words, the first label read corresponds to the first sample extracted. Since the order of the sub-samples is maintained throughout analysis, the first test cup number read is associated with the first test result produced by the Diclan. It can be seen that the test cup label may be read immediately before, after, or concurrent with sub-sample extraction. The important feature is that the labels are read in the same order that the sub-samples are extracted.

In present laboratory procedures, even in laboratories with computerization, a "load list" is typically made for automated instruments. This means that the samples must be placed in the instrument transport system in a prescribed order. This has several disadvantages: (a) mis-ordering causes results to be attributed to the wrong sample; (b) the instrument may not be started until all samples have been received and are in place; and (c) rush or emergency samples must either be placed at the end of the line when they arrive or the load list must be modified in a time-consuming step. With the present invention, these problems do not exist and the samples may go into the sample transport in any order since they are identified at the time the sample is entered into the instrument for analysis.

FIG. 12 shows a test station console. The apparatus and operation of the test station console is similar to the portable and transfer station consoles. Similar numerals are therefore used to designate similar elements. As shown in FIG. 11, read head 101 is preferably mounted in an atuomatic mechanism rather than being hand held. In such an embodiment, the test cup labels are provided with an alignment pin or notch so that the labels are all aligned in the same direction in the sample chain.

In FIG. 13 is shown the data entry system for interfacing the Diclan 240 clinical analyzer with the Honeywell H1602 computer. To understand the operation of this data entry system, it is first necessary to understand the generation and output of signals from the Diclan 240 clinical analyzer. A three digit sample accession number is displayed on a counter, and a three digit test result is displayed on Nixie tubes in the Diclan 240 clinical analyzer. Both numbers are also output to a printer 250.

The sample accession number is a sequential count of the Diclan test cups as they are analyzed. A starting ring is placed on the first Diclan test cup in a batch of samples to be tested, and subsequent test cups are sened by a Microswitch, which generates a positive pulse for each test cup. These pulses are counted and the count is held in a three digit electro-mechanical decimal counter.

Test results are generated by a photometric measurement. The photometer output with no test sample present charges a reference capacitor. The amount of the charge on the reference capacitor may be modified by calibration potentiometers. When the test sample is in place in the photometer beam, three events take place: an oscillator gate is opened; the reference capacitor begins discharging in small increments; and a comparator starts comparing the photometer output voltage with the voltage on the reference capacitor. The gate directs the oscillator pulses to the test result binary coded decimal (BCD) counter. When the reference and test sample voltage are equal the comparator shuts off the oscillator gate. Thus the number of oscillator pulses is proportional to the test result.

Data is transmitted to printer 250 by a set of ten digit lines. Six decimal digits (three for the sample number, and three for the test results) are sent serially in an interval of approximately two seconds. The transfer is initiated by a timing cam, and the transfer sequence is controlled by gating pulses under the direction of printer 250. The sample accession number is transferred to printer 250 first. A gate pulse applies voltage to the 10.sup.2 electro-mechanical decimal counter. The ten outputs of each of the electro-mechanical counters are connected to the ten data transmission digit lines, so the gate pulse causes the appropriate 10.sup.2 digit to be transferred to printer 250. The 10.sup.1 and 10.sup.0 electro-mechanical counters are gated in sequence to complete the transfer of the sample accession number. This procedure is then repeated for the test result BCD counters, resulting in that data being converted to a decimal format and sent to printer 250.

The data entry system shown in FIG. 13 provides an interface between the Diclan 240 clinical analyzer and H1602 computer by utilizing the data flow to printer 250. The data being transmitted to printer 250 is in decimal form. The data entry system converts the decimal data to the BCD format so that only four data lines, rather than ten data lines, are required to go to the computer.

FIG. 14 shows an example of the signals transmitted to the computer by the data entry system of FIG. 13. For the purpose of this example, the sample accession number is 127 and the test result is 805. It can be seen that in addition to the sample accession number and the test result number three other types of signals are directed to the computer: the "out-of-range" interrupt signal, the "data input" interrupt signal, and the "data envelope" interrupt signal.

The out-of-range interrupt signal indicates that the test result is out of range and therefore inaccurate. This signal corresponds to the red "overrange" light on the Diclan and a special out-of-range printer format on printer 250. If the test result is out of range, out-of-range alarm 252 sends an interrupt signal to the computer as shown in FIG. 14. This signal stays on as long as out-of-range samples are present. When a normal range sample appears, the out-of-range interrupt signal turns off.

Data input alarm 253 provides a data input interrupt signal. One signal is associated with the transfer of each BCD digit. The data input interrupt signal is derived from the transfer sequence signal from the printer and the gate pulses. Since both of these signals contain pulses other than the required alarm pulses, the desired data input alarm signal is derived by differentiating the sequence signal and then ANDing the result with the gate pulses.

Data envelope alarm 254 provides an interrupt signal at the beginning and the end of data transmission. The data envelope interrupt signals are derived from the Diclan timing cam.

It should be noted that the Diclan sample accession number is not utilized by the present patient-specimen identification system. This number may be discarded if desired by appropriate hardware or software modification.

MANUAL TEST STATION

In FIG. 15 is shown a reader and data entry means for use when the sample analysis is performed manually. After the analysis has been performed, the analysis result is entered into the console 300 by pressing the appropriate buttons on keyboard 301. The analysis result is displayed on display 302 and is also stored in a buffer memory. After the analysis result is verified by visually checking display 302, read head 303 is pressed against the sub-sample label. Random number z is read and the analysis result and random number z are sent to memory 13.

DATA ENTRY

In one embodiment of the present invention, the data entry means sends an interrupt signal to memory 13 and logic means 32. This interrupt signal indicates that data is about to be sent and that the pairs of random numbers should be stored in an associated manner in memory 13.

In the case of data entry from the transfer station and from the automated instrument, timing means 63 may provide the interrupt signal. The sequence of fourteen bits from the sense amplifiers is then sent to the memory by a line driver. Thus the fourteen bits from each label are entered into memory 13 as they are being read out.

In the case of the portable console, the random numbers x and y are read and stored in temporary memory 20 and later entered into memory 13. In this case, when connection is made to data output terminal 103 on the portable console an interrupt signal is sent to memory 13 and logic means 32. The random numbers are then sequentially entered into memory 13. First one random number is entered and then the random number associated with that number is entered.

As a random number is received from one of the data entry means, logic means 32 performs a parity check using the two parity bits. If there are no parity errors and the data is properly stored, a "data received" signal is sent to a data received flip flop located in the particular console which is sending the data. When the data received flip flop receives the data received pulse, it changes state and turns on data received indicator 114. This informs the technician or operator that the data has been received and the parity check found no error.

In a large patient-specimen identification system, there is a possibility that simultaneous interrupt signals may be sent to memory 13 from two different data entry means. This could result in erroneous information being stored. Another embodiment of the data entry means avoids this problem. In this preferred embodiment, each data entry means contains a small buffer memory to hold one or two sets of data. Logic means 32 and memory 13 cycle through the various data entry means every few seconds and interrogate each one as to whether it has data available. If a particular data entry means has data to be stored, a short time of exclusive use of logic and memory is allotted to that particular data entry means for dumping the data stored in the buffer memory into memory 13. In addition to eliminating a simultaneous interrupt problem, this preferred embodiment results in tighter control of the data and less chance of introducing spurious (noise) signals into memory 13.

ASSOCIATION AND CORRELATION

Although a variety of correlation techniques may be used with the present invention, one particularly advantageous correlation technique uses the computer instruction known as indirect addressing. With normal or direct addressing, the desired operation is performed on the contents of the address portion of the instruction. For example, LDA 20145 means "load into the A register of the computer the contents of memory address 20145". With indirect addressing, which is signified by setting a designated bit in the instruction word, the command is modified to mean "load into the A register the contents of the address which is in turn the contents of memory location 20145". The correlation technique can best be understood by reference to the following example.

When a patient 10 enters the hospital, random number x which appears on label 12 and the patient's identity are entered into memory 13 by first data entry means 14. Random number x is transformed into an address by adding address sector location A to random number x. Address sector location A is the first location in address sector No. 1. The patient's identity is then stored in location A+x, as shown in FIG. 16.

When a sample is taken from the patient, random number x from the patient's wrist label and random number y from the sample container label 16 are temporarily stored in an associated manner in temporary portable memory 20. Random number x and random number y are later transferred from temporary memory 20 to memory 13 by data entry means 21. Random number y is transformed into an address by adding address sector location B to it. Address sector location B is the first location in address sector No. 2. A+x is then stored in location B+y. It should be noted that since the addresses in address sector No. 2 correspond to the random numbers from the sample container labels, address sector No. 2 must be of a size equal to the number of sample container labels in the system, regardless of how many labels are actually being used on a given day.

When the sample is transferred to sub-sample containers, random number y and random number z are read and entered into memory 13. Random number z from the sub-sample label is transformed into an address by adding address sector location C to it. Address sector location C is the first location of address sector No. 3. As with address sector No. 2, address sector No. 3 must be as large as the total number of subsample labels in the system. An indirect address designation bit is then added to word B+y and the modified word is stored in location C+z.

When random number z arrives at memory 13 from fourth data entry means 31, the contents of location C+z are indirectly retrieved. Logic means 32 goes to location C+z and notes the contents. Since an indirect bit is included in the contents, logic means 32 goes into an indirect mode to address location B+y. Logic means 32 notes the contents of location B+y (A+x) and proceeds to location A+x. Logic means 32 takes the contents of location A+x (the patient's identity) and stores it temporarily.

When the test result from the sub-sample arrives at memory 13, it is paired with the patient's identity. This pairing may be in the form of a dual table-double word method as shown in address sector No. 4, or a direct address method, as shown in address sector No. 5, in which the patient's identity is the address and the test results are the contents.

Once the patient's identity and the test results are paired, they are typically printed out by printer 33. It may also be desirable to retain the paired information in memory 13 for future use. Sample number y and sub-sample number z are no longer needed once correlation has occurred. Address locations B+y and C+z may therefore be cleared so that the labels containing random numbers y and z may be reused. Similarly, when the patient leaves the hospital, address location A+x is cleared so that the label containing random number x may be reused.

It should be noted that the sets X, Y, and Z of random numbers may be separate and distinct components of a master set of random numbers. Alternatively, sets X, Y, and Z may intersect.

PATIENT-SPECIMEN IDENTIFICATION SOFTWARE

A flow diagram of the software system is found in FIG. 17. An executive routine contains the real-time clock data, initiates routines, holds buffers and carries out the housekeeping functions. The executive can either carry out a periodic search to see if flags are set for the various modules, or as shown in the flow diagram, the receipt of an input interrupt causes the executive to search for its source.

The patient census routine allows for the creation of a file for a new patient and sets aside memory space for data for that patient. The file structure is set up in alphabetic order by patient name for easy access. Provisions exist in this routine for data input and output from a file, and the file may be deleted when desired. At this point, groundwork is laid for the later correlation by setting up Table A in address sector No. 1, as described in the preceding section. The address corresponds to the wrist label number (A+x), with contents consisting of the patient's identity.

The portable memory transmit routine inputs blocks of data consisting of a wrist label number, the sample container numbers from the samples taken from the patient, and the time the sample was taken. The parity of the words is checked and compared with the parity bits sent with the data. If the data was received properly, the wrist label number is transformed for correlation (see Association and Correlation section) and it and the time of draw are stored in Table B in address sector No. 2, whose addresses (B+y) correspond to sample container numbers. A "transmission confirmed" or "data received" signal is then sent back to the transmit module.

The operation of the transfer station is analogous to the portable memory transmit routine, with the identification numbers being those belonging to the sample containers and sub-sample containers.

There are two functions within the automated instrument routine. One inputs the test result data from the analyzer and stores it sequentially in Table D. The other inputs the sub-sample identification numbers, checks parity, stores the numbers sequentially in Table E and confirms the transmit.

The correlation routine steps through Tables D and E, taking data from Table D, holding it in a buffer, taking a sub-sample identification from Table E, and performing an indirect addressing search through Tables C, B and A to get the patient's identity. The patient file for that identity is found and the test results are stored there, along with the time the sample was taken.

The data handling output routine is controlled from a keyboard and can work in several modes, two of which are illustrated here. The operator can ask for the results for a particular patient or group of patients, the files are searched to find the desired patients, and the patient's identity and results are printed. The laboratory supervisor often wishes to examine results by test, so provision is also made for the operator to request all the data from a particular test. A search is made and the test results and corresponding patient identities are printed. Other data handling and reporting routines can be incorporated in this section for the convenience of the user.

PROGRAMMABLE MULTI-CHANNEL ANALYSIS

Multi-channel instruments have been developed to perform several tests on one sample. Not all samples, however, require all tests in the instrument performed on them. To save cost and time, programmable instruments are being developed. The present invention greatly aids the efficiency of such instruments in the following manner. When the test sample number is read to the analyzer, correlation is made back to the unique bulk quantity identity, and the data file on that identity is scanned. The particular tests to be performed on the sample are noted (having been entered into the memory as part of the test request) and the memory/logic unit sends control signals to the analyzer to perform the required tests.

In conclusion, a system which reliably indentifies analysis results with the patient from whom the sample was taken has been disclosed. This patient-specimen identification system has been described in conjunction with a series of preferred embodiments. It should be understood that modifications can be made without departing from the spirit and scope of the present invention.

Claims

The embodiments of the invention in which an exclusive property or right is claimed are defined as follows:

1. In a system in which a test sample is taken from a bulk quantity having an unique identity and the test sample is analyzed, an improved method for reliably associating the analysis results with the bulk quantity, the improved method comprising:

attaching to the bulk quantity a machine-readable label having a unique bulk quantity number encoded thereon,

storing the unique identity and the bulk quantity number in an associated manner,

attaching a machine-readable label to each test sample taken from the bulk quantity, each machine-readable label having a unique test sample number encoded thereon,

reading the bulk quantity number and each of the test sample numbers,

storing the bulk quantity number and each of the test sample numbers in an associated manner,

reading the test sample numbers,

associating each test sample number with an analysis result obtained from analysis of the corresponding test sample,

correlating the analysis results to the unique identity, and

recording the analysis results and the unique identity in an associated manner.

2. The method of claim 1 wherein reading the test sample numbers and associating each test sample number with an analysis result comprises:

attaching a machine-readable label to each subsample taken from a test sample, each machine-readable label having a unique sub-sample number encoded thereon,

reading the test sample number and each of the sub-sample numbers,

storing the test sample number and each of the sub-sample numbers in an associated manner,

reading the sub-sample numbers, and

associating each sub-sample number with an analysis result obtained from analysis of the corresponding sub-sample.

3. The method of claim 1 wherein the bulk quantity is a human patient and the test sample is a fluid or tissue from the human patient.

4. The method of claim 1 wherein the test sample numbers are temporary numbers and wherein the method further comprises:

clearing the test sample numbers for reuse after correlating.

5. A method for analyzing samples from a patient and reliably reporting the analysis results, the method comprising:

attaching a machine-readable label to the patient, the machine-readable label containing unique random number x from a first set of random numbers X,

storing the patient's identity and random number x in an associated manner in memory means,

taking a sample from the patient,

placing the sample in a sample container having a machine-readable label attached thereto, the machine-readable label containing unique random number y from a second set of random numbers Y,

reading the machine-readable label attached to the patient,

reading the machine-readable label attached to the sample container,

storing random numbers x and y in an associated manner in a portable temporary memory,

transferring the associated random numbers x and y from the portable temporary memory to the memory means,

transferring portions of the sample from the sample container to a plurality of sub-sample containers, each sub-sample container having attached thereto a machine-readable label containing a unique random number z from a third set of random numbers Z,

reading the machine-readable label attached to the sample container,

reading the machine-readable labels attached to each of the sub-sample containers,

storing random number y and each random number z in an associated manner in the memory means,

analyzing the contents of at least one of the sub-sample containers,

reading the machine-readable label attached to the sub-sample container,

directing the analysis results and random number z to the memory means in an associated manner,

correlating the analysis results to the patient's identity, and

recording the analysis results and the patient's identity in an associated manner.

6. The method of claim 5 wherein the first, second and third sets X, Y and Z of random numbers comprise a master set of random numbers.

7. In a system in which a sample is taken from a patient, a sub-sample is taken from the sample, and the sub-sample is analyzed, improved means for reliably associating the analysis results with the patient, the improved means comprising:

memory means for storing pairs of data in an associated manner,

a machine-readable patient label for attachment to a patient, the machine-readable label containing a unique random number x from a first set of random numbers X,

first data entry means for directing the patient's identity and random number x to the memory means in an associated manner,

a machine-readable sample label for attachment to a sample from the patient, the machine-readable sample label containing a unique random number y from a second set of random numbers Y,

first reader means for reading the machine-readable patient label and for reading the machine-readable sample label,

portable temporary memory means for storing the random numbers x and y in an associated manner,

second data entry means for transferring the associated random numbers from the portable temporary memory means to the memory means,

a machine-readable sub-sample label for attachment to a sub-sample from the sample, the machine-readable sub-sample label containing a unique random number z from a third set of random numbers Z,

second reader means for reading the machine-readable sample label and for reading the machine-readable sub-sample label,

third data entry means for directing the random number y and the random number z to the memory means in an associated manner,

third reader means for reading the machine-readable sub-sample label,

fourth data entry means for directing the analysis results obtained from analysis of the sub-sample and random number z to the memory means in an associated manner,

logic means for correlating the analysis results to the patient's identity, and

recording means for recording the analysis results and the patient's identity in an associated manner.

8. The invention of claim 7 wherein the recording means comprises the memory means.

9. The invention of claim 7 wherein the recording means comprises printer means for printng the analysis results and the patient's identity in an associated manner.

10. The invention of claim 7 wherein the memory means and the logic means comprise a digital computer.

11. The invention of claim 7 wherein the machine-readable patient label also contains a human-readable representation of random number x.

12. The invention of claim 7 wherein the machine-readable sample label also contains a human-readable representation of random number y.

13. The invention of claim 7 wherein the machine-readable sub-sample label also contains a human-readable representation of random number z.

14. The invention of claim 7 wherein the sample is a liquid sample.

15. The invention of claim 14 wherein the liquid sample is blood.

16. The invention of claim 14 wherein the sample is contained in a sample container and wherein the sample label is adapted to be attached to the sample container.

17. The invention of claim 16 wherein the sub-sample is contained in a sub-sample container and wherein the sub-sample label is adapted to be attached to the sub-sample container.

18. The invention of claim 7 wherein the machine-readable patient label is adapted to be attached to a patient's wrist.

19. The invention of claim 7 wherein the machine-readable patient, sample, and sub-sample label may be read by common apparatus.

20. The invention of claim 19 wherein the machine-readable patient, sample, and sub-sample labels each contain machine-readable indicia to indicate whether the label is a patient, sample, or sub-sample label.

21. The invention of claim 7 wherein the machine-readable patient, sample, and sub-sample labels each contain a human-readable representation of the machine-readable random number contained thereon.

22. The invention of claim 21 and further comprising first display means for visually displaying random numbers x and y as read by first reader means.

23. The invention of claim 21 and further comprising second display means for visually displaying random numbers y and z as read by second reader means.

24. The invention of claim 21 and further comprising third display means for visually displaying random number z as read by third reader means.

25. Apparatus for correlating an identified bulk quantity with the analysis result of a test sample taken from the bulk quantity, the apparatus comprising:

a memory for storing pairs of data in an associated manner;

a machine-readable label for attachment to the bulk quantity and having a unique number;

first data entry means for directing the bulk quantity identity and the unique number to the memory in an associated manner;

a machine-readable label for attachment to a test sample and having a unique number;

a first reader for reading the labels;

a temporary memory for storing the bulk quantity label number and the test sample label number in an associated manner;

second data entry means for transferring the associated numbers from the temporary memory to the first mentioned memory;

a second reader for reading the test sample label number;

third data entry means for directing the test sample label number and an analysis result relating to the test sample in an associated manner to the first mentioned memory;

logic means for correlating the analysis result to the identified bulk quantity; and

a recorder for recording the analysis result and the identity of the bulk quantity in an associated manner.

26. Apparatus as in claim 25 wherein each of said numbers is picked at random from a predetermined group of numbers.

27. The Apparatus of claim 25 including:

a machine-readable label for attachment to a sub-sample taken from the test sample, the sub-sample label having a unique number thereon; and wherein the second reader in use reading the test sample label and the sub-sample label;

a third reader for reading the sub-sample label; and wherein the third data entry means includes two data entry devices, one for directing the test sample label number and the sub-sample label number in an associated manner to the first mentioned memory, and the other for directing the analysis of the sub-sample and the sub-sample label number in an associated manner to the first mentioned memory.