Patient monitoring for alarm management

Abstract

The patient monitoring device initiates an interval mode, which includes measuring blood pressure at predetermined intervals within a predetermined time period. The device obtains a first blood pressure measurement at one of the predetermined intervals and determines whether the first blood pressure measurement is abnormal. If the first blood pressure measurement is determined to be abnormal, the device obtains a second blood pressure measurement after a predetermined delay. The device compares the first blood pressure measurement with the second blood pressure measurement to determine whether the first blood pressure measurement is abnormal. If the first blood pressure measurement is determined to be abnormal, the device triggers an alarm.

Description

Background Art

[0001] During continuous patient monitoring, an alarm is typically set with a pair of upper and lower alarm limits. When a patient's physiological variable falls below the lower alarm limit or when the physiological variable rises above the upper alarm limit, the alarm is triggered.

[0002] Clinicians are often unable to determine whether an alarm was triggered due to patient deterioration or due to noise artifacts such as from patient motion. This can lead to confusion about the need to respond to the alarm and can cause alarm fatigue. Summary of the Invention

[0003] Generally speaking, the present disclosure relates to monitoring physiological variables for alarm management. Various aspects are described in this disclosure, including but not limited to the following.

[0004] In one aspect, a method of continuous patient monitoring includes: initiating an interval mode for measuring blood pressure, the interval mode including measuring blood pressure at predetermined intervals within a predetermined time period; obtaining a first blood pressure measurement result at one of the predetermined intervals; determining whether the first blood pressure measurement result is abnormal; when the first blood pressure measurement result is abnormal, obtaining a second blood pressure measurement result after a predetermined delay; comparing the first blood pressure measurement result and the second blood pressure measurement result to confirm whether the blood pressure is normal or abnormal; and when the blood pressure is confirmed to be abnormal, transmitting the blood pressure to an alarm management application.

[0005] In another aspect, a patient monitoring device includes: at least one processing device; and a memory device storing instructions that, when executed by the at least one processing device, cause the device to: initiate an interval mode for measuring blood pressure at predetermined intervals within a predetermined time period; obtain a first blood pressure measurement at one of the predetermined intervals; determine whether the first blood pressure measurement is abnormal; when the first blood pressure measurement is abnormal, obtain a second blood pressure measurement after a predetermined delay; compare the first blood pressure measurement and the second blood pressure measurement to confirm whether the blood pressure is normal or abnormal; and when the blood pressure is confirmed to be abnormal, transmit the blood pressure to an alarm management application.

[0006] In another aspect, a method of patient monitoring for alarm management includes inflating a cuff to have a partial pressure around a limb of the patient that is less than a pressure applied to the limb when measuring blood pressure; monitoring an internal pressure inside the cuff; determining a motion artifact based on changes in the internal pressure; and transmitting the motion artifact to delay an alarm triggered by an abnormal measurement received from a physiological sensor attached to the limb.

[0007] In another aspect, a patient monitoring device includes: at least one processing device; and a memory device storing instructions that, when executed by the at least one processing device, cause the device to: inflate a cuff to have a partial pressure around the patient's limb that is less than the pressure applied to the limb when measuring blood pressure; monitor the internal pressure inside the cuff; determine motion artifact based on changes in the internal pressure; and transmit the motion artifact to delay an alarm triggered by an abnormal measurement received from a physiological sensor attached to the limb.

[0008] In another aspect, a method of patient monitoring for alarm management includes receiving an electrocardiogram (ECG) signal from electrodes attached to a body; processing the ECG signal to determine motion artifacts, including calculating a motion value corresponding to the intensity of the motion artifacts; assigning a location to the motion value based on the location of the electrodes on the body; examining a sensor at the location of the motion value, the sensor being used to measure a physiological variable; calculating a motion-weighted value for the physiological measurement obtained from the sensor based on the motion value; and transmitting the motion-weighted value to an alarm delay algorithm.

[0009] In another aspect, a patient monitoring device includes: at least one processing device; and a memory device storing instructions that, when executed by the at least one processing device, cause the device to: receive an electrocardiogram signal from electrodes attached to the body; process the electrocardiogram signal to determine motion artifacts; assign a location to a motion value; examine a sensor at the location of the motion value, the sensor being used to measure a physiological variable; calculate a motion-weighted value for the physiological measurement obtained from the sensor based on the motion value; and transmit the motion-weighted value to an alarm delay algorithm.

[0010] In another aspect, a patient monitoring device includes: at least one processing device; and a memory device storing instructions that, when executed by the at least one processing device, cause the at least one processing device to: initiate an interval mode comprising measuring blood pressure at predetermined intervals within a predetermined time period; obtain a first blood pressure measurement at one of the predetermined intervals; determine whether the first blood pressure measurement is abnormal; when the first blood pressure measurement is determined to be abnormal, obtain a second blood pressure measurement after a predetermined delay; compare the first blood pressure measurement and the second blood pressure measurement to confirm whether the first blood pressure measurement is abnormal; and trigger an alarm when the first blood pressure measurement is determined to be abnormal.

[0011] In another aspect, a patient monitoring device includes: at least one processing device; and a memory device storing instructions that, when executed by the at least one processing device, cause the at least one processing device to: inflate a cuff around a patient's limb to have a partial pressure that is less than the pressure applied to the limb by the cuff when measuring blood pressure; monitor the internal pressure inside the cuff; identify motion artifacts based on changes in the internal pressure; and delay an alarm triggered by a physiological sensor based on the motion artifact.

[0012] In another aspect, a patient monitoring device includes: at least one processing device; and a memory device storing instructions that, when executed by the at least one processing device, cause the at least one processing device to: receive an electrocardiogram signal from electrodes attached to a body; identify motion artifacts from the electrocardiogram signal; assign a location to the motion artifact based on the location at which the electrodes are attached to the body; identify a sensor that acquires a physiological measurement at the location assigned to the motion artifact; calculate a motion weighting value based on the motion artifact of the physiological measurement acquired by the sensor; and use the motion weighting value in an alarm delay algorithm. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The following drawings, which form a part of this application, are illustrative of the described technology and are not meant to limit the scope of the present disclosure in any way.

[0014] Figure 1 An example of a system for monitoring physiological variables of a patient in a clinical setting is illustrated, the system including a monitoring device and a sensor.

[0015] Figure 2 Schematically illustrates Figure 1 Another example of a system comprising a monitoring device for monitoring a physiological variable and an additional sensor.

[0016] Figure 3 The diagram shows Figure 1 and Figure 2 An example of a method for continuous patient monitoring performed by a monitoring device.

[0017] Figure 4 The diagram shows Figure 1 and Figure 2 Another example of a method of continuous patient monitoring performed by a monitoring device.

[0018] Figure 5 The diagram shows Figure 1 and Figure 2 Another example of a method of continuous patient monitoring performed by a monitoring device.

[0019] Figure 6 The diagram shows Figure 1 and Figure 2 Another example of a method of continuous patient monitoring performed by a monitoring device.

[0020] Figure 7 The diagram shows Figure 1 and Figure 2 An example of a method for managing alarms performed by a monitoring device.

[0021] Figure 8 The diagram shows Figure 1 and Figure 2An example of a method of performing dynamic sorting of redundant physiological variables by a monitoring device.

[0022] Figure 9 The diagram shows Figure 1 and Figure 2 Examples of redundant physiological variables displayed on a display device of a monitoring device.

[0023] Figure 10 The diagram shows Figure 1 and Figure 2 Another example of redundant physiological variables displayed on a display device of a monitoring device. DETAILED DESCRIPTION

[0024] Figure 1 An example of a system 10 for monitoring physiological variables of a patient P in a clinical setting such as a hospital is illustrated. The monitored physiological variables include heart rate, respiratory rate, ECG, blood oxygen saturation (SpO2), end-tidal carbon dioxide (etCO2), etc. The system 10 includes sensors connected to a monitoring device 22 for monitoring physiological variables. Examples of sensors include an electrocardiogram (ECG) sensor 14, a pressure sensor 18, and an SpO2 sensor 24. The system 10 may also include Figure 2 The non-contact sensor 26 and etCO2 sensor 28 are shown in FIG.

[0025] As will be described in more detail below, physiological sensing and motion detection functionality are combined in one or more sensors in system 10. For example, pressure sensor 18 may be used to determine non-invasive blood pressure measurements and detect motion artifacts that may affect or influence physiological sensing performed by other sensors in system 10. Additionally, or alternatively, ECG sensor 14 may be used to measure electrocardiogram signals and detect motion artifacts that may affect or influence physiological sensing performed by other sensors in system 10.

[0026] System 10 includes a cuff 12, which is shown positioned around the upper arm of a patient P. Cuff 12 is comfortable to wear, allowing patient P to wear cuff 12 for extended periods of time, such as during twenty-four-hour blood pressure monitoring. Cuff 12 is connected to a cuff controller 16 and a pressure sensor 18, both of which are connected to a monitoring device 22.

[0027] In some examples, cuff 12, cuff controller 16, and pressure sensor 18 are integrated into a single device, such as a blood pressure monitor or sphygmomanometer. In some examples, the blood pressure monitor or sphygmomanometer is a separate device connected to monitoring device 22. Alternatively, the blood pressure monitor or sphygmomanometer can be integrated with monitoring device 22 into a single device.

[0028] The cuff controller 16 is used to inflate the cuff 12 until blood flow under the cuff 12 is blocked, and then slowly release the cuff 12 in a controlled manner to gradually allow blood flow under the cuff 12. The cuff controller 16 may include a pump or similar device to inflate the cuff 12. For example, the cuff controller 16 may inflate the cuff 12 with air to increase the pressure of the cuff 12 around the upper arm of the patient P. The cuff controller 16 may control the amount of pressure applied by the cuff 12 around the upper arm of the patient P.

[0029] Pressure sensor 18 functions as a non-invasive blood pressure sensor. Pressure sensor 18 detects a first signal from the partially occluded blood vessel beneath cuff 12 while cuff controller 16 slowly and controlledly releases pressure from cuff 12. The first signal is generated by blood flowing through the partially occluded blood vessel. Pressure sensor 18 can sample the first signal multiple times at varying intervals.

[0030] When the cuff is at least partially inflated, the pressure sensor 18 detects a second signal from a pressure change inside the cuff 12. The pressure sensor 18 is located within or around the cuff 12 to detect pressure changes inside the cuff. When the cuff 12 is partially inflated, the pressure sensor 18 can detect pressure changes within the cuff, which can be caused by the patient P shifting their weight, such as moving from a supine position to a lateral position or a sitting position while resting in bed. Thus, the pressure sensor 18 also serves as a motion sensor to detect movement that can affect other physiological variable readings. This can eliminate the need for a dedicated motion sensor, such as an accelerometer attached to the patient P, or a piezoelectric sensor, a load cell, or a combination thereof, that detects movement of the patient P while the patient is supported on a bed or similar support structure.

[0031] Pressure sensor 18 transmits the first signal and the second signal to monitoring device 22, which processes the first signal and the second signal to generate an output. For example, monitoring device 22 may process the first signal to non-invasively estimate the systolic and diastolic blood pressures of patient P. Furthermore, monitoring device 22 may process the second signal to detect motion artifacts that may affect or influence physiological data acquired by monitoring device 22 from other sensors in system 10, such as physiological variables monitored by ECG sensor 14, SpO2 sensor 24, non-contact sensor 26, and EtC2 sensor 28.

[0032] Thus, the second signal acquired from pressure sensor 18 can be combined with data acquired from other sensors in system 10 to determine whether the irregular physiological variable reading is caused by motion artifact. For example, when the motion artifact detected from pressure sensor 18 indicates that the movement of patient P may be interfering with the electrocardiogram reading from ECG sensor 14, monitoring device 22 can instruct ECG sensor 14 to cancel or reacquire the electrocardiogram reading, or mark the electrocardiogram reading as potentially erroneous due to movement.

[0033] like Figure 1 As shown, the ECG sensor 14 includes a plurality of electrodes 20 that are attached to the body of the patient P. For example, the electrodes 20 may be attached to various locations on the patient P's chest, right arm, left arm, right leg, left leg, and head.

[0034] Electrodes 20 are connected to ECG sensor 14 via lead wires 21. ECG sensor 14 may be a 3-lead, 5-lead, or 12-lead ECG machine. ECG sensor 14 uses signals acquired from electrodes 20 to monitor the electrical activity of the heart of patient P, for example, by generating an electrocardiogram that can be displayed on a display device and / or printed.

[0035] The ECG sensor 14 also transmits signals to the monitoring device 22 as raw data, which can be used to detect motion artifacts that can affect or influence physiological data obtained from other sensors in the system 10. The signals from the ECG sensor 14 can be analyzed to determine the location of the motion artifact. For example, the signal can be classified based on the location of the electrodes so that the signal can be used to detect motion artifacts on the right arm, left arm, right leg, left leg, etc. Thus, the ECG sensor 14 can be used as a motion sensor. This can eliminate the need for a dedicated motion sensor, such as an accelerometer attached to the patient P, or a piezoelectric sensor, a load cell, or a combination thereof, to detect the patient's movement when the patient is supported on a bed or similar structure.

[0036] Monitoring device 22 uses motion artifacts detected from signals acquired from ECG sensor 14 to improve physiological data acquired from other sensors in system 10. For example, when the signal from ECG sensor 14 detects patient motion that may interfere with a blood pressure measurement from pressure sensor 18, monitoring device 22 may cancel or reacquire the blood pressure measurement, or flag the blood pressure measurement as potentially erroneous due to motion. Thus, the signal acquired from ECG sensor 14 may be combined with physiological data from other sensors in system 10 to determine whether irregular physiological variable readings are caused by motion.

[0037] like Figure 1As further shown, the SpO2 sensor 24 is a clip attached to a finger of the patient P. Alternatively, the SpO2 sensor 24 may be attached to other body parts of the patient P, such as the patient's earlobe. The SpO2 sensor 24 is connected to the monitoring device 22 and transmits data to the monitoring device 22 to estimate the blood oxygen saturation of the patient P.

[0038] like Figure 1 As shown, monitoring device 22 communicates with server 200 via communication network 100. Server 200 operates to manage the medical history and information of patient P. Server 200 may be operated by a healthcare provider, such as a hospital or medical clinic. Monitoring device 22 transmits physiological data acquired from sensors in system 10 to server 200 via connection to communication network 100. In at least some examples, server 200 is a cloud server or similar type of server.

[0039] The server 200 may include an electronic medical record (EMR) system 202 (or electronic health record (EHR)). Advantageously, the server 200 may store physiological data acquired from sensors in the system 10 in an electronic medical record (EMR) 204 or electronic health record of the patient P located in the EMR system 202 via a connection with the monitoring device 22 over the communication network 100.

[0040] The communication network 100 transfers data between one or more devices, such as between the monitoring device 22 and the server 200. The communication network 100 may also be used to transfer data between one or more sensors and devices in the system 10, such as the ECG sensor 14, the cuff controller 16, the pressure sensor 18, and the SpO2 sensor 24, as well as other sensors and devices such as the ECG sensor 14, the cuff controller 16, the pressure sensor 18, and the SpO2 sensor 24. Figure 2 Between the contactless sensor 26 and the etCO2 sensor 28 shown.

[0041] The communication network 100 may include any type of wired or wireless connection, or any combination thereof. Examples of wireless connections include cellular network connections, such as 4G or 5G. Wireless connections may also be implemented using Wi-Fi, ultra-wideband (UWB), Bluetooth, radio frequency identification (RFID), and the like.

[0042] Figure 2 Another example of a system 10 is schematically illustrated, comprising a monitoring device 22 and sensors for monitoring physiological variables of a patient. In this example, in addition to the ECG sensor 14, the pressure sensor 18, and the SpO2 sensor 24, a contactless sensor 26 and an etCO2 sensor 28 are also connected to the monitoring device 22.

[0043] Non-contact sensor 26 is a sensor that can continuously monitor a patient's physiological variables without physically contacting the patient. For example, non-contact sensor 26 can be positioned on a bed frame beneath a patient's mattress in a clinical setting. Non-contact sensor 26 can be used to measure physiological variables such as the patient's heart rate and respiratory rate. An example of non-contact sensor 26 is described in U.S. Patent No. 9,775,758, the entire contents of which are incorporated herein by reference.

[0044] The etCO2 sensor 28 is a sensor that measures the level of carbon dioxide released at the end of exhaled breath, called end-tidal carbon dioxide (etCO2). The etCO2 sensor 28 can also be used to measure the patient's breathing rate. The etCO2 sensor 28 can be attached to a breathing tube, mask, or similar breathing device.

[0045] like Figure 2 As shown, monitoring device 22 includes a computing device 120 having at least one processing device 122 and a memory device 124. At least one processing device 122 is an example of a processing unit such as a central processing unit (CPU). In some examples, at least one processing device 122 may include one or more digital signal processors, field programmable gate arrays, or other electronic circuits.

[0046] The memory device 124 operates to store data and instructions for execution by the at least one processing device 122, including, as described in more detail below, an interval measurement application 126, a motion detection application 128, and an alarm management application 130. The memory device 124 includes computer-readable media, which may include any media that can be accessed by the monitoring device 22. By way of example, computer-readable media include computer-readable storage media and computer-readable communication media.

[0047] Computer-readable storage media includes volatile and nonvolatile, removable and non-removable media implemented in any device configured to store information such as computer-readable instructions, data structures, program modules, or other data. Computer-readable storage media may include, but are not limited to, random access memory, read-only memory, electrically erasable programmable read-only memory, flash memory, and other memory technologies, including any media that can be used to store information that can be accessed by monitoring device 22. Computer-readable storage media are non-transitory.

[0048] Computer-readable communication media embody computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and includes any information delivery media. The term "modulated data signal" refers to a signal that has one or more of its characteristics changed or set in such a manner as to encode information in the signal. By way of example, computer-readable communication media include wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, radio frequency, infrared, and other wireless media. Combinations of any of the above are also within the scope of computer-readable media.

[0049] Monitoring device 22 uses interval measurement application 126 to execute an interval mode for measuring physiological variables. For example, cuff controller 16, pressure sensor 18, and monitoring device 22 can operate in interval mode, in which blood pressure readings are taken at predetermined intervals over a predetermined time period. Cuff 12 is continuously worn by patient P, and interval measurement application 126 instructs cuff controller 16 to inflate cuff 12 at each interval, while simultaneously using pressure sensor 18 to non-invasively estimate the patient's systolic and diastolic blood pressures P as cuff controller 16 slowly releases pressure from cuff 12 in a controlled manner. As an illustrative example, interval mode can occur over a 24-hour period, with each interval occurring every 20 or 30 minutes during the 24-hour period.

[0050] The motion detection application 128 detects patient motion using one or more sensors connected to the monitoring device 22. The motion detection application 128 can detect patient motion using the cuff 12, the cuff controller 16, and the pressure sensor 18. For example, the motion detection application 128 can instruct the cuff controller 16 to inflate the cuff 12 to maintain a partial pressure around the limb (e.g., arm) of the patient P. The partial pressure is a pressure that allows patient motion to be detected from changes in internal pressure within the cuff 12, which can be caused by the patient P shifting their weight while resting on a surface such as a bed. The pressure changes within the cuff 12 are detected by the pressure sensor 18.

[0051] The partial pressure is less than the pressure applied to the patient's arm when measuring their blood pressure. Furthermore, the partial pressure is less than the safe venous return pressure (SVRP), a patient safety standard that defines the pressure limit for proper venous return and prevents excessive blood pooling. For adults, the SVRP is 15 mmHg. For neonates, the SVRP is 5 mmHg.

[0052] In one example, cuff 12 is inflated to maintain the partial pressure between intervals in interval mode. In another example, when monitoring device 22 is not operating in interval mode, cuff 12 is inflated to maintain the partial pressure for consecutive time periods. In another example, during continuous monitoring of physiological variables including heart rate, respiratory rate, blood oxygen saturation (SpO2), end-tidal carbon dioxide (etCO2), etc., when an abnormal reading is received from one of the other sensors connected to monitoring device 22, cuff 12 is inflated to maintain the partial pressure.

[0053] The motion detection application 128 can detect patient motion using signals from the ECG sensor 14. For example, the motion detection application 128 can instruct the at least one processing device 122 to use one or more filters to analyze the signals received from the ECG sensor 14 to detect motion. Examples of the one or more filters used to filter the signals from the ECG sensor 14 may include a bandpass filter, a bandstop filter, a high-pass filter, and a low-pass filter.

[0054] The alarm management application 130 can automatically cancel, delay, and / or reset one or more alarms that are triggered when patient motion is detected (e.g., due to one or more physiological variables exceeding an upper alarm limit or falling below a lower alarm limit) from the motion detection application 128. Advantageously, the alarm management application 130 can eliminate the need for a clinician to manually cancel, delay, and / or reset the alarms.

[0055] The alarm management application 130 may also provide a selectable time delay for alarm events (e.g., when an abnormal blood pressure measurement is received in interval mode) that can be adjusted by the clinician. For example, a default time delay may be set to two minutes after an alarm is triggered, and the clinician may adjust the time delay to a 10-minute delay through a user interface displayed on the display device 114 of the monitoring device 22. The time delay allows the clinician to complete tasks in another room when the alarm is not a threat to the patient.

[0056] The monitoring device 22 also includes a sensor interface 132 that operates to communicate with the various sensors of the system 10. The sensor interface 132 may include a wired interface and a wireless interface. The ECG sensor 14, the pressure sensor 18, the SpO2 sensor 24, the contactless sensor 26, and the etCO2 sensor 28 may be wirelessly connected to the sensor interface 132 via Wi-Fi, ultra-wideband (UWB), Bluetooth, and similar types of wireless connections. Alternatively, or in addition to wireless connections, the ECG sensor 14, the pressure sensor 18, the SpO2 sensor 24, the contactless sensor 26, and the etCO2 sensor 28 may also be connected to the monitoring device 22 using a wired connection that plugs into the sensor interface 132.

[0057] like Figure 2 As shown, the monitoring device 22 includes a display device 114 that operates to display one or more user interfaces. In some examples, the display device 114 is a touch screen, so that the user interface operates to receive input from a clinician. In such examples, the display device 114 operates as both a display device and a user input device. The monitoring device 22 may also support physical buttons on the device housing that operate to receive input from the clinician to control the operation of the monitoring device and enter data.

[0058] The monitoring device 22 may also include an audio unit 134. The audio unit 134 generates audio sounds, such as an alarm, when an alarm is triggered by the alarm management application 130. Additionally, the audio unit 134 may be used to provide instructions.

[0059] Figure 3 An example of a method 300 of continuous patient monitoring is illustrated. The method 300 may be performed by the interval measurement application 126 using the cuff 12, cuff controller 16, and pressure sensor 18 to reacquire non-invasive blood pressure measurements during interval mode when an abnormal blood pressure measurement is detected.

[0060] Method 300 overcomes the obstacles in interval mode, in which the cuff 12 remains on the patient's arm for a predetermined period of time (e.g., 24 hours) and automatically triggers a blood pressure measurement at predetermined intervals (e.g., every 20 or 30 minutes). In interval mode, blood pressure measurements are often reported without the presence of a clinician, making it impossible for the clinician to retake a blood pressure measurement or perform a manual blood pressure reading to confirm whether an abnormal blood pressure measurement is true or accurate. This can result in inaccurate blood pressure measurements being recorded by the monitoring device 22 and stored in the patient's EMR 204. Furthermore, this can trigger false alarms and lead to alarm fatigue.

[0061] An abnormal blood pressure measurement is one that is above the upper alarm limit or below the lower alarm limit. The upper and lower alarm limits are based on normal values ​​or default values. Normal resting blood pressure for adults is approximately 120 / 80 mmHg, hypertension in adults is considered 140 / 90 mmHg or higher, and hypotension in adults is considered 90 / 60 mmHg or lower. Therefore, an abnormal blood pressure measurement is one that is above 140 / 90 mmHg or below 90 / 60 mmHg. Furthermore, an abnormal blood pressure measurement is one in which a blood pressure measurement was not obtained due to a technical error.

[0062] Method 300 includes an operation 302 of initiating an interval mode for measuring blood pressure. In interval mode, cuff 12 remains on the patient's arm for a predetermined period of time (e.g., 24 hours) and blood pressure measurements are automatically triggered at predetermined intervals (e.g., every 20 or 30 minutes).

[0063] Next, method 300 includes operation 304 of obtaining a blood pressure measurement according to the interval pattern. The blood pressure measurement obtained at operation 304 is referred to herein as a first blood pressure measurement. The blood pressure measurement is obtained by inflating the cuff 12 using the cuff controller 16 until blood flow beneath the cuff 12 is blocked, then slowly releasing the cuff 12 in a controlled manner to gradually allow blood flow beneath the cuff 12, while simultaneously detecting signals from the partially blocked blood vessels beneath the cuff 12 using the pressure sensor 18 for non-invasive estimation of systolic and diastolic blood pressure. The blood pressure measurement at operation 304 is automatically measured without the need for assistance from the patient, a clinician, or other personnel surrounding the patient.

[0064] Next, method 300 includes operation 306, which determines whether the blood pressure measurement result obtained from operation 304 is abnormal (i.e., outside the upper alarm limit or the lower alarm limit, or not obtained due to a technical error). When the blood pressure measurement result is not abnormal such that it is within the normal range (i.e., "No" at operation 306), method 300 proceeds to operation 312, which transmits the blood pressure measurement result.

[0065] When the blood pressure measurement result obtained from operation 304 is outside the upper alarm limit and the lower alarm limit or the blood pressure measurement result is not obtained due to a technical error, making the blood pressure measurement result abnormal (i.e., "yes" at operation 306), method 300 proceeds to operation 308 of re-obtaining the blood pressure measurement result. The blood pressure measurement result re-obtained at operation 308 is referred to herein as a second blood pressure measurement result or a third blood pressure measurement result in some cases.

[0066] Operation 308 is performed after a predetermined delay, which is an amount of time after the blood pressure measurement is initially obtained in operation 304. For example, the blood pressure is re-obtained at operation 308 at least 30 seconds after the blood pressure measurement is initially obtained in operation 304. This prevents the cuff 12 from being continuously or repeatedly inflated for extended periods of time, which could affect blood circulation and cause blood to pool. The predetermined amount of time between operations 304 and 308 can be based on regulatory standards for a long-term automatic mode of measuring blood pressure.

[0067] Next, method 300 proceeds to operation 310, where the second blood pressure measurement retrieved at operation 308 is compared to the first blood pressure measurement retrieved at operation 304 to determine whether the patient's blood pressure is normal or abnormal. In some examples, the determination at operation 310 is based on whether both the first blood pressure measurement and the second blood pressure measurement are abnormal. In other examples, the determination at operation 310 is based on whether the second blood pressure measurement matches the first blood pressure measurement or is within a predefined threshold of the first blood pressure measurement.

[0068] When the blood pressure is confirmed to be abnormal (i.e., "yes" at operation 310), the method 300 proceeds to operation 312, which performs an action based on the confirmed abnormal blood pressure measurement. Operation 312 may include triggering an alarm during the interval mode, for example, by transmitting the confirmed abnormal blood pressure measurement to the alarm management application 130. Additionally or alternatively, operation 312 may include storing the blood pressure in the EMR 204 via the communication network 100.

[0069] In the example where the blood pressure is determined to be normal (ie, “NO” at operation 310 ), method 300 includes storing the second blood pressure measurement retrieved at operation 308 in EMR 204 via communication network 100 .

[0070] In some examples, when the blood pressure is not confirmed to be abnormal (i.e., "No" at operation 310), method 300 proceeds to operation 314 to determine whether a delay limit has been reached. The delay limit is based on the allowed delay between blood pressure measurements. The delay limit can be a default value or can be a value set by the clinician based on the patient's condition. For example, when the patient is healthy, the delay limit can allow for a longer delay because there is less urgency to receive a blood pressure measurement. However, when the patient is in a deteriorating condition, such as due to sepsis, the delay limit is shorter because there is a greater urgency to receive a blood pressure measurement.

[0071] When the delay limit is not reached (i.e., "No" at operation 314), method 300 may optionally proceed to operation 316 in which instructions are provided to the patient. As an illustrative example, the abnormal blood pressure measurement may be due to patient motion, which results in an incorrect blood pressure measurement or the absence of a blood pressure measurement due to a technical error. In some cases, method 300 may include receiving data from another sensor in system 10, such as ECG sensor 14, indicating that the patient is moving. In such an example, the instructions provided in operation 316 may be for the patient to remain still or stop moving so that the blood pressure measurement can be reacquired without motion artifacts.

[0072] In some examples, the instruction provided in operation 316 is an audio message played back by the audio unit 134 of the monitoring device 22. Alternatively, or in addition to the audio message, the instruction provided in operation 316 may be a message displayed on the display device 114, or may be a flashing light that is interpreted by the patient as an instruction to remain still while the blood pressure monitor reacquires their blood pressure.

[0073] Next, the method 300 repeats reacquiring the blood pressure measurement at operation 308. Operation 308 is performed after a predetermined delay (eg, 30 seconds) has elapsed since the blood pressure measurement was previously reacquired at operation 308.

[0074] The method 300 repeats operation 310, this time comparing the third blood pressure measurement result reacquired at operation 308 with the first blood pressure measurement result acquired at operation 304 to confirm whether the blood pressure is normal or abnormal. When the blood pressure is confirmed to be abnormal (i.e., "yes" at operation 310), the method 300 proceeds to operation 312, which transmits the confirmed blood pressure measurement result, which may include the first blood pressure measurement result, the second blood pressure measurement result, the third blood pressure measurement result, or the average of the first blood pressure measurement result, the second blood pressure measurement result, and the third blood pressure measurement result.

[0075] In some examples, when the blood pressure is confirmed to be normal (i.e., "No" at operation 310), method 300 includes transmitting the third blood pressure measurement result re-obtained at operation 308 to server 200 via communication network 100 for storage in EMR 204. Alternatively, when the blood pressure is not confirmed (i.e., "No" at operation 310), the method proceeds again to operation 314 to determine whether the delay limit has been reached.

[0076] When the delay limit is reached (i.e., "yes" at operation 314), method 300 proceeds to operation 318, which may include determining an average of the blood pressure measurements obtained at operation 304 and the blood pressure measurements re-acquired at operation 308. Alternatively or additionally, operation 318 may include determining a majority value (i.e., the most frequently occurring blood pressure measurement, i.e., the mode value) of the blood pressure measurements obtained at operation 304 and the blood pressure measurements re-acquired at operation 308. Operation 312 may include transmitting at least one of the average value and the majority value of the blood pressure measurements obtained in operations 304 and 308.

[0077] At operation 312, method 300 may include sending the blood pressure measurement to server 200 for storage in the patient's EMR 204 located in EMR system 202. Additionally, alarm management application 130 may retrieve the blood pressure measurement sent at operation 312 to trigger an alarm if the measurement is abnormal. Advantageously, method 300 may reduce false alarms when monitoring device 22 is operating in an interval mode for measuring blood pressure.

[0078] Figure 4Another example of a method 400 for continuous patient monitoring is shown. The method 400 is performed to detect patient motion during continuous physiological variable monitoring. The method 400 can be performed by the motion detection application 128 installed on the monitoring device 22 using the cuff 12, the cuff controller 16, and the pressure sensor 18.

[0079] Method 400 can be performed to detect patient motion during interval mode, which is used to measure physiological variables by interval measurement application 126. In some cases, method 400 is performed to detect patient motion between systolic and diastolic blood pressure measurement intervals. Thus, method 400 can be performed to monitor patient motion whenever cuff 12 is not being used to measure patient blood pressure. In method 400, cuff 12 can be used as a continuous motion sensor.

[0080] Patient motion can affect or influence the signals received by monitoring device 22 from other physiological sensors in system 10, resulting in erroneous readings. Furthermore, patient motion naturally causes changes in some physiological variables, such as heart rate and respiratory rate. Advantageously, alarm management application 130 installed on monitoring device 22 can use patient motion detected according to method 400 to cancel, delay, or reset an alarm triggered by an abnormal reading received by one of the other sensors connected to monitoring device 22.

[0081] Method 400 includes an operation 402 for checking the status of cuff 12 to determine whether cuff 12 is being used to measure blood pressure. For example, blood pressure can be measured at predetermined intervals (e.g., 30 minutes) over a predetermined period of time (e.g., 24 hours) using cuff 12 during interval mode. When cuff 12 is being used to measure blood pressure (i.e., "yes" at operation 404), method 400 returns to operation 402 for checking the blood pressure measurement status. When a blood pressure measurement is not in progress (i.e., "no" at operation 404), method 400 proceeds to operation 406 for instructing cuff controller 16 to partially inflate cuff 12.

[0082] At operation 406, the motion detection application 128 instructs the cuff controller 16 to inflate the cuff 12 to have a partial pressure sufficient to enable the pressure sensor 18 (which is located within or about the cuff 12) to detect internal pressure changes within the cuff 12. The partial pressure allows the pressure sensor 18 to detect internal pressure changes within the cuff 12, which may be caused by patient motion, such as when a patient shifts their weight to move from a supine position to a sitting upright position while supported on a surface such as a bed.

[0083] At operation 406, the motion detection application 128 instructs the cuff controller 16 to inflate the cuff 12 to have a partial pressure less than the pressure applied to the patient's arm when estimating the patient's blood pressure. In addition, the partial pressure is less than the SVRP (e.g., less than 15 mmHg for adults and less than 5 mmHg for newborns).

[0084] Next, method 400 proceeds to operation 408, which monitors the internal pressure inside cuff 12 to determine if there are any pressure changes inside cuff 12. As described above, pressure changes inside cuff 12 may be a result of a patient shifting their weight while supported on a surface such as a bed and may be used to detect patient movement.

[0085] When no pressure change is detected (i.e., "No" at operation 410), method 400 returns to operation 408 and continues to monitor the internal pressure inside cuff 12. When a pressure change is detected (i.e., "Yes" at operation 410), method 400 proceeds to operation 412, which processes the pressure change inside cuff 12 to determine motion artifacts.

[0086] Operation 412 includes processing the raw data obtained from the pressure sensor 18 to determine motion artifacts. In some examples, the raw data is processed to calculate a motion value that quantifies the intensity or density of the motion artifacts. The processing at operation 412 may also include normalizing the motion value to be on a common scale.

[0087] Processing the raw data in operation 412 may also include assigning a location to the motion artifact. For example, the motion artifact may be assigned to the location of the arm to which the cuff 12 is attached. The alarm management application 130 may use the location of the motion artifact to determine the effect or influence on physiological variables measured by other sensors at the same location, such as blood oxygen saturation measured by the SpO2 sensor 24 attached to the same arm as the cuff 12.

[0088] Next, the method 400 proceeds to operation 414, which communicates the motion artifact and the assigned location to the alarm management application 130. The motion artifact can be used as input to an algorithm executed by the alarm management application 130 to cancel, delay, and / or reset one or more alarms triggered by an abnormal reading from another sensor in the system 10. Additionally, the motion artifact can be used to determine a dynamic ranking of redundant physiological variables, as will be described in more detail below.

[0089] Additionally, monitoring device 22 may use motion artifacts to improve blood pressure measurements taken during interval mode. For example, when motion artifacts are detected within a predetermined amount of time (e.g., 30 seconds) prior to a scheduled blood pressure measurement according to interval mode, monitoring device 22 may issue a warning or instruct the patient to remain still prior to the scheduled measurement.

[0090] Figure 5 Another example of a method 500 for continuous patient monitoring is shown. The method 500 may be performed by the motion detection application 128 installed on the monitoring device 22 using the cuff 12, the cuff controller 16, and the pressure sensor 18. The method 500 includes many of the operations included in the method 400.

[0091] Method 500 differs from method 400 in that method 500 includes operation 502 of receiving an abnormal reading from another sensor in system 10. The abnormal reading triggers method 500 to perform operations 504-512 using cuff 12, cuff controller 16, and pressure sensor 18 to detect patient motion. Alarm management application 130 can use this information to cancel, delay, and / or reset one or more alarms triggered by the abnormal reading. Thus, method 500 is executed when an abnormal reading is received from another sensor in system 10, causing cuff 12 to function as an event-driven motion sensor. This differs from method 400, which is executed when cuff 12 is not being used to measure patient blood pressure to continuously monitor patient motion.

[0092] As an illustrative example, operation 502 may include receiving an abnormal SpO2 reading from an SpO2 sensor 24 attached to the same patient arm as the cuff 12 (see Figure 1 When an abnormal SpO2 reading is received, the method 500 performs operations 504-512 using the cuff 12, cuff controller 16, and pressure sensor 18 to determine whether patient motion artifacts are present on the patient's arm to which the SpO2 sensor 24 is attached. Thus, the method 500 is performed to verify whether the abnormal reading from the SpO2 sensor 24 is due to patient motion, and the alarm management application 130 uses this information to cancel, delay, and / or reset one or more alarms triggered by the abnormal SpO2 reading.

[0093] After receiving the abnormal reading in operation 502, method 500 includes operation 504 of instructing the cuff controller 16 to partially inflate the cuff 12 (see the description of operation 406 in method 400); operation 506 of monitoring the pressure inside the cuff 12 (see the description of operation 408 in method 400); operation 508 of determining whether a pressure change is detected inside the cuff 12 (see the description of operation 410 in method 400); operation 510 of determining a motion value (see the description of operation 412 in method 400); and operation 512 of communicating the motion artifact to the alarm management application 130 (see the description of operation 414 in method 400).

[0094] Similar to method 400, the motion artifacts passed in operation 512 may be used as input to an algorithm executed by the alarm management application 130. Furthermore, the motion artifacts passed in operation 512 may be used to determine a dynamic ranking of redundant physiological variables, as will be described in greater detail below.

[0095] Figure 6 Another example of a method 600 for continuous patient monitoring is shown. The method 600 is performed by the motion detection application 128 installed on the monitoring device 22 using the ECG sensor 14. The method 600 is performed to detect patient motion based on raw ECG signals acquired from the electrodes 20 of the ECG sensor 14.

[0096] During continuous patient monitoring, physiological sensors are susceptible to patient motion artifacts. For example, each sensor in the system 10 can be affected based on the intensity and location of the patient motion artifact, either individually or in combination with other sensors in the system 10. As will be described in greater detail, the method 600 analyzes the raw ECG signal from the ECG sensor 14 to determine the intensity and location of the patient motion artifact, which the alarm management application 130 can use to cancel, delay, and / or reset one or more alarms triggered during continuous physiological variable monitoring.

[0097] Now refer to Figure 6 , the method 600 includes an operation 602 of receiving a raw ECG signal from the ECG sensor 14. As described above, the raw ECG signal is detected by the electrodes 20 attached to the patient's body and transmitted to the ECG sensor 14 through the lead wires 21. The ECG sensor 14 can then send the raw ECG signal to the monitoring device 22. In an alternative example, when the lead wires 21 are directly connected to the monitoring device 22, the monitoring device 22 can receive the raw ECG signal directly from the electrodes 20.

[0098] Next, method 600 includes an operation 604 of processing the raw ECG signal to determine motion artifacts. Motion artifacts are determined from signal noise in the raw ECG signal. The signal noise can be filtered to improve the detection of motion artifacts. For example, low-frequency noise is used to identify motion artifacts, while high-frequency noise is excluded.

[0099] In some examples, the processing performed at operation 604 may include calculating a motion value corresponding to the intensity or magnitude of the motion artifact. Operation 604 may further include normalizing the motion value to a scale corresponding to motion values ​​obtained from other sensors in system 10 (e.g., from pressure sensor 18).

[0100] Next, the method 600 includes an operation 606 of determining the location of the motion artifact. Figure 6Operation 606 is shown occurring after operation 604 is completed, but in alternative examples, operation 606 may occur before operation 604. Furthermore, in some cases, operations 604 and 606 may occur substantially simultaneously, such that they are concurrent.

[0101] As described above, the ECG sensor 14 includes electrodes 20 (see FIG. 1 ) attached to various locations on the body of the patient P, such as the chest, right arm, left arm, right leg, left leg, and head. Figure 1 The position of the motion artifact is determined based on the position of the electrode 20 that detects the raw ECG signal. For example, a motion artifact detected from the electrode 20 connected to the patient's right arm is mapped to the right arm position, a motion artifact detected from the electrode 20 connected to the patient's left arm is mapped to the left arm position, a motion artifact detected from the electrode 20 connected to the patient's right leg is mapped to the right leg position, a motion artifact detected from the electrode 20 connected to the patient's left leg is mapped to the left leg position, and so on.

[0102] Additionally, the raw ECG signals from multiple electrodes 20 can be combined to determine the direction of the motion artifact. For example, the direction from the right arm to the left leg can be determined by processing the raw ECG signals from electrodes 20 attached to the patient's right arm and left leg. Similarly, the direction from the right arm to the left arm can be determined by processing the raw ECG signals from electrodes 20 attached to the patient's right arm and left arm. Other examples are possible. Thus, in some examples, the motion value calculated from the raw ECG signals is a vector indicating the direction of the patient's motion.

[0103] Next, the method 600 proceeds to operation 608 where the motion artifacts and their locations are communicated to the alarm management application 130. The motion artifacts communicated in operation 608 may be used as input to an algorithm executed by the alarm management application 130. Furthermore, the motion artifacts communicated in operation 608 may be used to determine a dynamic ranking of redundant physiological variables.

[0104] Figure 7 Illustrated is an example of a method 700 of managing alarms performed by the alarm management application 130 when installed on the monitoring device 22. The method 700 may be performed to delay an alarm when patient motion is detected.

[0105] Method 700 includes an operation 702 of receiving motion artifacts from sensors in system 10. As described above, motion artifacts are determined based on raw data acquired from sensors in system 10, such as pressure sensor 18 or ECG sensor 14 for measuring physiological variables (e.g., blood pressure, electrocardiogram readings), so that the sensors function as both physiological sensors and motion sensors. This can eliminate the need for dedicated motion sensors, thereby reducing the number of sensors in system 10.

[0106] In some examples, method 700 includes an operation 704 of pre-processing raw motion artifacts from each sensor to determine a motion value. As an illustrative example, operation 704 may include executing the following algorithm:

[0107] (i) motion_r = process(r)

[0108] Where motion_r is the motion value, and r is the raw motion artifact collected from the sensor. Therefore, the motion value can be calculated independently of the sensor source, such as pressure sensor 18 or ECG sensor 14. When processing the raw motion artifact from ECG sensor 14, the motion value can be calculated as a vector to indicate the direction of motion. Each motion value can be assigned a location, such as indicating whether it originated from the right or left arm.

[0109] In other examples, method 700 receives pre-processed motion values ​​in operation 702, such that operation 704 need not be performed in method 700. Instead, motion artifacts may have been pre-processed, such as by performing operation 412 in method 400, operation 510 in method 500, and / or operation 604 in method 600.

[0110] Next, method 700 may include determining whether the motion value exceeds a predetermined threshold at operation 706. Operation 706 is performed so that only motion values ​​that are sufficient to affect or influence the reading from another sensor in system 10 are considered for adjusting the alarm setting. When the motion value does not exceed the predetermined threshold (i.e., "No" at operation 706), the motion value may be ignored and method 700 returns to operation 702 and continues to receive motion artifacts.

[0111] When the motion value exceeds the predetermined threshold (i.e., "yes" at operation 706), method 700 proceeds to operation 708, which checks for sensors measuring physiological variables at the same location where the motion value was detected. When no other sensors are located at the same location as the determined motion value (i.e., "no" at operation 710), method 700 returns to operation 702 and continues to receive motion artifacts.

[0112] When it is determined that at least one other physiological sensor is at the same location as the detected motion value (i.e., "yes" at operation 710), method 700 proceeds to operation 712, which calculates a motion-weighted value for the physiological measurement received from the sensor located at the same location. For example, when a motion value is detected on the left arm of patient P due to signal noise from the raw ECG signal acquired from the electrode 20 attached to the left arm of patient P, operation 710 determines whether there are any other physiological sensors attached to the left arm of patient P.

[0113] exist Figure 1 In the example shown, the cuff 12 and the pressure sensor 18 (for measuring the systolic and diastolic blood pressures of the patient P) are also attached to the left arm of the patient P. In addition, the SpO2 sensor 24 (for measuring the blood oxygen saturation of the patient P) is also attached to the left arm of the patient P.

[0114] A motion-weighted value is calculated from the motion value and used by an alarm delay algorithm, which is executed to delay an alarm when an abnormal physiological measurement is detected. For example, when an abnormal SpO2 measurement is detected, the alarm delay algorithm delays triggering an alarm for a predetermined period of time (e.g., 10 seconds) to determine whether the SpO2 measurement returns to a normal range. As another example, the alarm delay algorithm can determine the extent to which the abnormal SpO2 measurement is outside the normal range and how long it lasts to determine whether to trigger an alarm.

[0115] The motion weighting value influences the effect of an abnormal physiological measurement on the alarm delay algorithm's decision to trigger an alarm. For example, when an abnormal physiological measurement is received while a high motion value is detected, the abnormal physiological measurement is assigned a low motion weighting value. As a result, the abnormal physiological measurement will have less influence or will be ignored by the alarm delay algorithm when determining when to trigger an alarm.

[0116] The motion weighting value used by the alarm delay algorithm is calculated according to the following algorithm:

[0117] (ii)weight_m=m*normalize(motion_r)

[0118] Where motion_r is the motion value, and m is the multiplier. The multiplier m is defined for each pairing of a sensor and a physiological variable alarm. For example, a multiplier m of 0.01 may be assigned to a motion value detected from the pressure sensor 18 for use with an SpO2 alarm. As another example, a multiplier m of 0.5 may be assigned to a motion value detected from the ECG sensor 14 for use with an SpO2 alarm.

[0119] The normalize() function can use any normalization algorithm (e.g., min-max, standard score). In addition, depending on the distribution of weight_m, other types of transformations can be applied, such as logarithmic transformation.

[0120] In view of the foregoing, a larger motion value (motion_r) results in a smaller motion weighting value (weight_m), so that abnormal physiological measurements will have less impact or will be ignored for determining when to trigger an alarm. For abnormal physiological measurements detected when there is little or no patient motion, a smaller motion value (motion_r) will result in a larger motion weighting value (weight_m). The motion weighting value (weight_m) is then used by the alarm delay algorithm, which can be executed by the alarm management application 130 to determine when to trigger or delay an alarm.

[0121] Figure 8 An example of a method 800 for dynamically ranking redundant physiological sensors performed by monitoring device 22 is illustrated. Method 800 is performed for physiological variables captured by multiple sensors in system 10. Method 800 assigns sensor confidence levels based on motion artifacts detected according to any of the methods described above. The sensor confidence levels can be used to adjust the ranking of redundant sensors to reduce inaccurate measurements used in alarm decisions. Thus, method 800 can be used to reduce false alarms, thereby reducing alarm fatigue.

[0122] Method 800 includes operation 802, which receives motion artifacts from sensors in system 10. As described above, motion artifacts are determined based on raw data acquired from sensors (e.g., pressure sensor 18, ECG sensor 14) in system 10 that are used to measure physiological variables (e.g., blood pressure, electrocardiogram readings), such that the sensors function as both physiological sensors and motion sensors. This can eliminate the need for dedicated motion sensors, thereby reducing the number of sensors used by system 10.

[0123] Next, the method 800 proceeds to operation 804, which checks for sensors measuring physiological variables at the same location of the determined motion artifact. When there are no other sensors at the same location of the determined motion value (i.e., "No" at operation 806), the method 800 returns to operation 802 and continues to receive motion artifacts.

[0124] When it is determined that at least one other physiological sensor is at the same location as the detected motion value (i.e., "yes" at operation 806), method 800 proceeds to operation 808, which adjusts the confidence level of one or more physiological variables measured by the sensor at the same location as the determined motion artifact.

[0125] Return Reference Figure 1 and Figure 2, there are multiple sensors that can redundantly measure physiological variables. For example, heart rate can be determined based on data acquired from ECG sensor 14, SpO2 sensor 24, or non-contact sensor 26. Thus, there are at least three sets of redundant heart rate measurements: a first set determined based on data acquired from ECG sensor 14, a second set determined based on data acquired from SpO2 sensor 24, and a third set determined based on data acquired from non-contact sensor 26.

[0126] As another example, the respiratory rate of patient P may be determined based on data acquired from etO2 sensor 28 and data acquired from contactless sensor 26. Thus, there are two sets of redundant respiratory rate measurements: a first set determined based on etO2 sensor 28 data, and a second set determined based on contactless sensor 26 data.

[0127] In some examples, each sensor has a default confidence level such that, when there are redundant sensors that can measure the same physiological variable, some sensors are preferred over other sensors for measuring certain physiological variables. For example, ECG sensor 14 may be preferred over other sensors that can also be used to measure heart rate (e.g., SpO2 sensor 24). Alternatively, in some cases, SpO2 sensor 24 may be preferred over other sensors (e.g., ECG sensor 14) for measuring heart rate.

[0128] In operation 808, method 800 reduces the confidence level of the sensor measuring the physiological variable at the same location as the determined motion artifact. As an illustrative example, when the motion artifact is determined to be on the patient's left arm (e.g., based on raw ECG signals collected from electrodes 20 attached to the patient's left arm), and the SpO2 sensor 24 is also attached to the patient's left arm (see FIG. Figure 1 ), due to the potential influence of detected motion artifacts, the data acquired from the SpO2 sensor 24 is assigned a lower confidence level, making it likely to be inaccurate and cause false alarms.

[0129] Next, method 800 includes operation 810, which updates the redundant sensor ranking of the physiological variables captured by the plurality of sensors. In the above example, because the SpO2 sensor 24 is located at a location where motion artifacts are detected, the heart rate measurement from the SpO2 sensor 24 is assigned a lower confidence level, and the SpO2 sensor 24 is assigned a lower ranking than other sensors for measuring heart rate that are not affected by motion artifacts (e.g., the ECG sensor 14 that measures heart rate using electrodes attached to the chest of the patient P, or the contactless sensor 26 that can continuously monitor heart rate without physical contact with the patient).

[0130] Redundant sensor ranking can be used to select certain sensors over other sensors to measure physiological variables. For example, monitoring device 22 may select ECG sensor 14 or non-contact sensor 26 to measure the patient's heart rate over SpO2 sensor 24 because the ECG sensor 14 and non-contact sensor 26 each have a higher ranking than SpO2 sensor 24 based on the position of motion artifacts.

[0131] Figure 9 The diagram illustrates an example of redundant physiological variables displayed on the display device 114 of the monitoring device 22. In this example, the heart rate measurement from the SpO2 sensor 24 has a greater variance than the heart rate measurement from the ECG sensor 14. This may be due to motion artifacts having a greater impact on the data acquired from the SpO2 sensor 24 than on the data acquired from the ECG sensor 14. Therefore, in this example, the heart rate measurement from the SpO2 sensor 24 is assigned a lower confidence level than the heart rate measurement from the ECG sensor 14. Consequently, the ECG sensor 14 may be assigned a higher redundant sensor ranking than the SpO2 sensor 24, such that the ECG sensor 14 is selected to measure heart rate instead of the SpO2 sensor 24.

[0132] Figure 10 Another example of redundant physiological variables displayed on the display device 114 of the monitoring device 22 is shown. In this example, the heart rate measurement from the ECG sensor 14 has a greater variance than the heart rate measurement from the SpO2 sensor 24. This may be due to motion artifacts having a greater impact on the data acquired from the ECG sensor 14 than on the data acquired from the SpO2 sensor 24. Therefore, in this example, the heart rate measurement from the ECG sensor 14 is assigned a lower confidence level than the heart rate measurement from the SpO2 sensor 24. Therefore, the SpO2 sensor 24 may be assigned a higher redundant sensor ranking than the ECG sensor 14, such that the SpO2 sensor 24 is selected to measure heart rate instead of the ECG sensor 14.

[0133] The various embodiments described above are provided by way of illustration only and should not be construed as limiting in any way. Various modifications may be made to the above embodiments without departing from the true spirit and scope of the present disclosure.

Claims

1. A patient monitoring device comprising: at least one processing device; as well as a memory device storing instructions that, when executed by the at least one processing device, cause the at least one processing device to: activating an interval mode, the interval mode comprising measuring blood pressure at predetermined intervals within a predetermined time period; obtaining a first blood pressure measurement at one of the predetermined intervals; determining whether the first blood pressure measurement result is abnormal; When the first blood pressure measurement result is determined to be abnormal, obtaining a second blood pressure measurement result after a predetermined delay; comparing the first blood pressure measurement result and the second blood pressure measurement result, and confirming that the first blood pressure measurement is abnormal when the second blood pressure measurement result is within a predefined threshold of the first blood pressure measurement result; as well as An alarm is triggered when the first blood pressure measurement result is confirmed to be abnormal.

2. The patient monitoring device according to claim 1, wherein The instructions, when executed by the at least one processing device, further cause the at least one processing device to: At least one of the first blood pressure measurement, the second blood pressure measurement, and an average of the first blood pressure measurement and the second blood pressure measurement is stored in an electronic medical record.

3. The patient monitoring device according to claim 1, wherein The instructions, when executed by the at least one processing device, further cause the at least one processing device to: determining whether a delay limit for one of the predetermined intervals has been reached; When the delay limit is reached, determining an average of the first blood pressure measurement and the second blood pressure measurement; and The average value is stored in the electronic medical record.

4. The patient monitoring device according to claim 1, wherein The instructions, when executed by the at least one processing device, further cause the at least one processing device to: determining whether a delay limit for one of the predetermined intervals has been reached; providing an instruction to remain stationary when the delay limit is not reached; and A third blood pressure measurement is obtained after the predetermined delay.

5. The patient monitoring device according to claim 4, wherein The instructions, when executed by the at least one processing device, further cause the at least one processing device to: determining at least one of an average and a majority of the first blood pressure measurement, the second blood pressure measurement, and the third blood pressure measurement when the delay limit is reached; as well as The average value or the majority value is stored in an electronic medical record.

6. The patient monitoring device according to claim 4, wherein: The delay limit is based on an allowed delay of the second blood pressure measurement during one of the predetermined intervals.

7. The patient monitoring device according to claim 1, wherein The instructions, when executed by the at least one processing device, further cause the at least one processing device to: inflating a cuff around a patient's limb to have a partial pressure less than a pressure applied by the cuff to the limb while measuring the blood pressure in the interval mode; monitoring an internal pressure within the cuff; identifying motion artifacts based on changes in the internal pressure; and An alarm triggered by a physiological sensor is delayed based on the motion artifact.

8. The patient monitoring device according to claim 7, wherein: The instructions, when executed by the at least one processing device, further cause the at least one processing device to: checking a status of the cuff during the interval mode of measuring the blood pressure; as well as When the state of the cuff indicates that the cuff is not used to measure the blood pressure in the interval mode, the cuff is inflated to have the partial pressure.

9. The patient monitoring device according to claim 7, wherein: The instructions, when executed by the at least one processing device, further cause the at least one processing device to: receiving anomaly measurements from the physiological sensors; and The cuff is inflated to have the partial pressure in response to the abnormal measurement.

10. The patient monitoring device according to claim 7, wherein: The instructions, when executed by the at least one processing device, further cause the at least one processing device to: assigning a location to the motion artifact based on the position of the cuff; identifying one or more sensors that acquire physiological measurements at the location assigned to the motion artifact; calculating a motion weighting value based on the motion artifact of the physiological measurement acquired by the one or more sensors in the location assigned to the motion artifact; as well as The motion weighted value is used in an alert delay algorithm.

11. The patient monitoring device according to claim 7, wherein: The instructions, when executed by the at least one processing device, further cause the at least one processing device to: assigning a location to the motion artifact based on the position of the cuff; identifying a sensor that acquires a physiological measurement at the location assigned to the motion artifact; adjusting a confidence level of the physiological measurement obtained from the sensor; and The redundant sensor ranking is updated using the confidence level.

12. The patient monitoring device according to claim 1, wherein The instructions, when executed by the at least one processing device, further cause the at least one processing device to: receiving electrocardiogram signals from electrodes attached to the body; identifying motion artifacts from the electrocardiogram signal; assigning a location to the motion artifact based on the location at which the electrode is attached to the body; identifying a sensor to acquire a physiological measurement at the location of the motion artifact; calculating a motion weighting value based on the motion artifact of the physiological measurement acquired by the sensor; as well as The motion weighted value is used in an alert delay algorithm.

13. The patient monitoring device according to claim 12, wherein: The instructions, when executed by the at least one processing device, further cause the at least one processing device to: adjusting a confidence level of the physiological measurement obtained from the sensor; and The redundant sensor ranking is updated using the confidence level.

14. The patient monitoring device according to claim 12, wherein: The instructions, when executed by the at least one processing device, further cause the at least one processing device to: receiving electrocardiogram signals from a plurality of electrodes; determining a direction of the motion artifact using the electrocardiogram signal; and The motion weight value is calculated as a vector.

15. The patient monitoring device according to claim 12, wherein: The motion artifact is determined based on signal noise in the electrocardiogram signal, and the electrocardiogram signal is filtered to exclude high frequency noise.

16. The patient monitoring device according to claim 12, wherein: The instructions, when executed by the at least one processing device, further cause the at least one processing device to: Identifying motion artifacts from inflatable cuffs used to measure blood pressure; calculating a motion weighted value using the motion artifact from the inflatable cuff; as well as The motion weighted value calculated based on the electrocardiogram signal is normalized to be on a common scale with the motion weighted value calculated based on the inflatable cuff.

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