Patent Application
20080077021
The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself however may be best understood by reference to the following detailed description of the invention, which describes certain exemplary embodiments of the invention, taken in conjunction with the accompanying drawings in which:
The BPM 12 includes a cuff 18, a pump (not shown) for delivering pressure to the cuff, and the calculating device 10, which includes a pressure sensor 22, a central processing unit (CPU) 24, a memory 26, a display 28, a power source 29 and a communication interface 30. In at least one embodiment, the cuff 18, the pump and the calculating device 10 can be contained within a single unit, i.e. a single housing. The cuff 18 at least partially surrounds a wrist 32 of the patient 16. The pressure sensor 22 is electrically connected to the cuff 18 through a wire 34. It should be appreciated that in other embodiments, a wireless connection can be used for communication between the cuff 18 and pressure sensor 22. The pressure sensor 22 measures the blood pressure within the cuff 18 and transmits a sensed blood pressure value to CPU 24. The CPU 24 calculates blood pressure values, such as the systolic blood pressure and the diastolic blood pressure, based on the sensed blood pressure and data contained in memory 26, which can include data for calculating blood pressure values and data for calibrating the sensed blood pressure measurements. The display 28 displays blood pressure values calculated by CPU 24. In at least one embodiment, the memory 26 can be configured to store machine instructions, e.g. software and/or firmware and CPU 24 can be adapted to execute the machine instructions. The machine instructions can include a counting routine for counting the number of uses of the BPM 12. The memory can store a recalibration value defined as a number of operations since last calibration. The value can be in the range of 2,000 or 5,000 to 7,000 to 15,000. In at least one embodiment, the value is 10,000. The counting routine can also include functionality for triggering display of a recalibration alert on display 28 upon reading the recalibration value.
In at least one embodiment, the BPM 12 can include a shock sensor 31 for sensing whether the BPM 12 has undergone a shock event, e.g. whether it has been dropped or exposed to extreme temperatures (e.g. T≧120° C.). Upon sensing a shock event, a shock signal can be sent to CPU 24, which can be configured to execute machine instructions for causing display of a shock alert on display 28.
The calculating device 10 is adapted to communicate with other devices, such as calibration device 14, through communication interface 30, which can be configured to receive and transmit data from a wired and/or wireless connection depending on the implementation of the present invention. According to
The power source 29 is electrically connected to the CPU 24 and provides power to pressure sensor 22, memory 26, display 28, and communication interface 30.
The calibration device 14 includes a central processing unit (CPU) 38, a pressure unit 40, a communication interface 42, a key unit 44, a display 46, memory 48, and power source 49. The calibration device 14 is electrically connected to the calculating device 10 through communication interface 42 and wired connection 36, although a wireless connection is also contemplated. The communication interface 42 can include an RS-232 interface.
The CPU 38 can be adapted to carry out one or more steps of a calibration process for calibrating BPM 12. In at least one embodiment, the CPU 38 is adapted to execute machine instructions for carrying out one or more steps of the calibration process and memory 48 is adapted to store machine instructions that are to be executed by the CPU 38. The memory 48 can be non-volatile memory, for example, read-only memory or flash memory, and can be configured to store pressure values for calibration and/or calibration software. Moreover, memory 48 can be configured as calibration firmware.
The pressure unit 40 is electrically connected to the CPU 38 and the BPM 12. The pressure unit 40 includes an air pressure circuit 50 for transmitting pressure point signals to the CPU 38 and the pressure sensor 22 of the BPM 12. In at least one embodiment, the transmission of the pressure point signal from air pressure circuit 50 to pressure sensor 22 passes through communication interface 42, although in other embodiments, the transmission can occur directly between air pressure circuit 50 and pressure sensor 22. The air pressure circuit 50 can also transmit pressure point signals to a pressure sensor 52, which generates a sensed pressure value based on each pressure point signal. The generated sensed pressure value can be transmitted to CPU 38 by pressure sensor 52.
In at least one embodiment, the pressure unit 40 additionally includes a motor, an electronic valve, a tank and an air conduit (e.g. a tube) to generate and deliver pressurized air at various pressures to the pressure sensor 22 and/or pressure sensor 52. The pressure point signals can be generated and delivered as the pressurized air at desired pressures.
The key unit 44 is electrically connected to the CPU 38. The key unit 44 can include one or more input buttons for selecting one or more operation modes of the calibration device 14. Non-limiting examples of operation modes include a calibration mode for calibrating the BPM 12 and a training mode for training the BPM 12. The key unit 44 can also include a test button (not shown). Upon activation, e.g. pressing the test button, the calibrating device 14 can execute one or more steps for identifying whether a calibration condition has been met, as described in
The display 46 is electrically connected to the CPU 38. The display can be configured to display one or more calibration values processed by the CPU 38. A non-limiting example of display 46 is a liquid crystal display (LCD).
The power source 49 is electrically connected to the CPU 38 and provides power to pressure unit 40, communication interface 42, key unit 44, and display 46.
As depicted in
Decision block 76 tests whether or not a calibration condition has been met for the BPM 12. In at least one embodiment, this determination is made by reference to the process set forth in
In at least one embodiment, the calibration device 14 can be configured to enter calibration mode and perform a calibration sequence prior to each operation of BPM 12.
In block 104, the air pressure circuit 50 transmits the pressure point signal (PS) to the pressure sensor 52 of the calibration device 14 and the pressure sensor 22 of the calculating device 10.
In block 106, the pressure sensor 52 of the calibration device 14 senses the pressure of the pressure point signal to obtain a sensed pressure value (SPC), which is stored in memory 48 of the calibration device 14.
In decision block 108, the calculating device 10 tests whether the pressure point signal has been received. If no, the process is returned to block 102 for generating a new pressure point signal. If yes, the pressure sensor 22 of BPM 12 senses the pressure of the pressure point signal to obtain a sensed pressure value (SPB), as depicted in block 110.
According to block 112, SPB is transmitted to the calibration device 14. In decision block 114, the calibration device 14 tests whether SPB has been received from the calculating device 10. If no, the process is returned to block 112 for re-transmitting the SPB. If yes, then SPB and SPC are compared at block 116 to determine whether the pressure values are within a tolerable range of each other. In at least one embodiment, the tolerable range can be in the range of 0 mm Hg to 50 mm Hg, 40 mm Hg, 30 mm Hg, 20 mm Hg, 10 mm Hg, 5 mm Hg, 3 mm Hg, or 1 mm Hg. Alternatively, the tolerable range for the SPB can be defined as a percentage plus and minus of SPC. The percentage can be in the range of 1% to 5%, 10%, 20%, or 25%. For instance, if SPC is 250 mm Hg and the percentage is 10%, then the percentage plus and minus values are 275 mm Hg and 225 mm Hg, i.e. the defined tolerable range for the SPB.
In decision block 118, the calibration device 14 tests whether the SPB and SPC are within the tolerable range. If no, then an “out of range” message can be displayed on display 24 (block 120) and the calibration device enters training mode (block 122). If the sensed pressure is within the tolerable range, then the process can be repeated for different pressure points, as depicted in decision block 124. For example, the process can be carried out for 0, 50, 150 and/or 250 mm Hg as different pressure points.
In block 152, the calibration device 14 generates a first training pressure point signal for comparison purposes. In at least one embodiment, the pressure point signal corresponds to a relatively low level of pressure (TPL), which can be in the range of 200 or 250 to 250 or 300 mm Hg.
In block 154, the calibration device 14 transmits the first training pressure point signal to the pressure sensor 22 of the calculating device 10. In decision block 156, the calculating device 10 tests whether the first training pressure point signal has been received. If no, the process is returned to block 152 for re-generating the first training pressure point signal. If yes, the pressure sensor 22 senses the pressure of the pressure point signal to obtain a sensed first pressure value (SPL), as depicted in block 158.
According to block 160, SPL is transmitted to the calibration device 14. In decision block 162, the calibration device 14 tests whether SPL has been received from the calculating device 10. If no, the process is returned to block 160 for re-transmitting SPL. If yes, the calibration device 14 generates a second training pressure point signal for comparison purposes, as depicted in block 164. In at least one embodiment, the pressure point signal corresponds to a relatively high level of pressure (TPH), which can be in the range of 250 or 300 to 300 to 350 mm Hg.
In block 166, the calibration device 14 transmits the second training pressure point signal generated in block 164 to the calculating device 10 of BPM 12. In decision block 168, the calculating device 10 tests whether SPH has been received. If no, the process is returned to block 164 for re-generating the second training pressure point signal. If yes, the pressure sensor 22 senses the pressure of the second pressure point signal to obtain a second sensed pressure value (SPH), as depicted in block 170.
According to block 172, SPH is transmitted to the calibration device 14. In decision block 174, the calibration device 14 tests whether SPH has been received by the calibration device 14. If no, the process is returned to block 172 for re-transmitting SPH. If yes, then the calibration device 14 generates calibration data, as depicted in block 176. The calibration data can include, but is not limited to, TPL and TPH.
In block 178, the calibration data and SPL and SPH are stored in the memory 26 of calculating device 10. This data can be used to recalibrate BPM 12, according to a method known to one skilled in the art. Advantageously, the combination of calibration data, e.g. TPL and TPH and SPL and SPH, provides a set of data for efficient and effective calibration because, in part, the data includes controlled and sensed data at relatively low and high pressure points.
As required, detailed embodiments of the present invention are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary of an invention that may be embodied in various and alternative forms. Therefore, specific functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for the claims and/or as a representative basis for teaching one skilled in the art to variously employ the present invention.
