A medical assessment system

Abstract

A medical assessment system includes a central station 2, a reuseable wearable medical device (3, Figure 1), and a calibration system (1, Figure 1). The central station 2 may include a touch-screen d

Description

The invention relates to a medical assessment system that utilises and measures a patient's bio signals, blood pressure and movement in a controlled and repeatable manner prior to consultation with a clinician. The system conveys the measured data to the clinician in advance of a consultation. The invention also relates to a method for determining how a patient is in a state of blood pressure measurement readiness so that a more reliable blood pressure measurement may be taken. Background There is a current and predicted healthcare professional shortfall. A recent re-assessment of the global health workforce predicts a ten million staffing shortfall in 2030 (Boniol et al). Vital signs measurements are an important component of an annual check up but often not measured as part of a general practice visit. A recent study, (Hayes E et al) shows that in patient cases where the six physiological vital signs, (mental state, temperature, blood pressure, heart rate, oxygen saturation and respiratory rate are required to be recorded, only 1.7% of patients had complete vital signs records. This is even more astonishing as 100% of patients had their mental state recorded, clearly demonstrating the problems were entirely where equipment was required to measure the vital signs and over 98% of patients thus had incomplete or unrecorded physical assessments. A 2021 study, (Dall'Ora, C. et al) states that the uninterrupted time to measure vital signs in a hospital by a nurse is 5 minutes and 1 second. The World Health Organisation stipulates that the patient whose blood pressure is being measured should "relax and to sit on a chair with their feet on the floor, legs uncrossed, back supported, ideally for at least 5 minutes" before measurement, (WHO 2020). A 2016 study of patients with known or suspected hypertension, (Levy J et al), indicated that 77% of clinicians did not adhere to the measurement guideline and suggests that such practice could result in misdiagnosis and overtreatment of hypertension. Additionally, white coat hypertension, which is elevated patient blood pressure in the presence of healthcare professionals is estimated to have a 13% incidence in the general population, (Nuredini G et al) Using only one vital sign, blood pressure, there is comprehensive evidence of non-adherence to measurement guidelines and indeed substantial cases where patients alert in the presence of a clinician results in temporal elevated blood pressure. Both non-adherence and white coat hypertension could result in unnecessary home blood pressure monitoring, misdiagnosis and even mistreatment. US9314171B2 (Omron Healthcare Co Ltd) discloses means to determine if a patient is at rest by recording the patients pulse wave period using a pressure transducer or similar during measurement, storing it in memory and then at the next clinical examination comparing the pulse periods to determine if the patient is at rest. This requires the correct identification of a pulse period where the patient is at rest and does not describe how the rest condition is objectively identified. The rest condition state is only then identified during measurement and does not identify and trigger a measurement in advance. US9724046B2 (Rossmax Int Ltd) discloses an apparatus that detects a series of pulses through the blood pressure measurement cuff while measuring the blood pressure. The apparatus records a patient's status during blood pressure measurement and not prior to taking a blood pressure measurement. The need to measure blood pressure and other bio signals in a controlled and repeatable manner prior to consultation is important both from a manpower and clinical accuracy perspective. There is a real need for an improved approach to measuring bio signals, blood pressure and movement and encourage and enforce better medical practice. Statements of Invention According to the invention there is provided a medical assessment system comprising a central station, a reuseable wearable medical device and a calibration system. Preferably the medical assessment system comprises means for measuring weight, height, bioimpedance and vital signs including blood pressure, heart rate, respiration rate, peripheral oxygen saturation and core temperature. In one embodiment of the invention the central station engages with a user, directs the user to login, measures their height and weight, measures their temperature, dispenses a wearable medical device to the user and receives the wearable medical device after use. In one embodiment of the invention the central station comprises a computer system; a display screen; a temperature measurement unit; a weight measurement unit; a height measurement unit; a patient communication system; a plurality of device enclosure modules; and means for receiving, conveying and dispensing a reuseable wearable medical device. In one embodiment of the invention the computer system comprises a microprocessor, RAM, wireless cellular communication, capable of communicating with the wearable device receiving and transmitting medical data to an Electronic Healthcare Record (EHR) system. In one embodiment of the invention the device enclosure modules comprise; a receiving unit; an inspection unit a cleaning unit; a functional assessment and charging unit; a communications unit; and a dispensing unit In one embodiment of the invention the cleaning unit comprises a set of rotating rollers, sterile cleaning material and UV lights. In one embodiment of the invention the wearable medical device comprises; an ECG unit; a photoplethysmography unit; an accelerometer and gyroscope unit; thermal sensor; an electric air pump; a blood pressure cuff; a short range secure wireless communication unit; a battery pack; an inductive charging unit; a display screen; and a patient communication system. Preferably the wearable medical device comprises attachment means for securely attaching and detaching the device to a user's arm. In one embodiment of the invention the wearable medical device detects and records ECG and PPG bio signals, measures blood pressure by occluding the radial artery and determines the user's movements and after measurement completes securely communicates the medical data to the central station. In one embodiment the wearable medical device is conveyed through the device enclosure modules in the central station, communicates the medical data measurements in the wearable medical device securely to the central station and is cleaned and validated ready for reuse. In another embodiment of the invention the calibration system comprises; a physical interface that enables the wearable medical device to be calibrated; an arbitrary function generator that emits an ECG signal to the wearable medical device; means to absorb PPG light emissions and transmit expected return signals that mimic various blood oxygenation levels and heart rate patterns; a pressure transducer measuring the pressure exerted by the blood pressure cuff on the wearable medical device; a wireless interface that enables the wearable medical device to be recalibrated; and a physical interface that enables the wearable medical device to be recalibrated. According to the invention there is provided a method for determining the optimum conditions to measure blood pressure using the medical assessment system comprising detecting a bio signal plateau conversant with blood pressure measurement and initiating a blood pressure measurement. According to the invention there is further provided a method for determining the optimum conditions to measure a person's blood pressure comprising detecting a bio signal plateau conversant with blood pressure measurement. In one embodiment the method comprises the steps of; acquiring signals from a person's heart activity and vascular system; removing noise and unwanted transitory signals; identifying the ECG peaks; calculating the heart pulse rate; and determining the standard deviation of interpeak durations for the temporal window of analysis signalling that blood pressure measurement can commence. In one embodiment the method comprises the additional steps of; acquiring bioimpedance; acquiring a skin temperature measurement of the person; identifying the PPG peaks; and calculating the pulse transit time. In another embodiment the method comprises the additional steps of; determining the polynomial fitting of the interpeak durations. Preferably the method comprises the step of initiating a blood pressure measurement when a bio signal plateau conversant with blood pressure measurement has been detected. According to the invention there is provided a wearable medical device for determining the optimum conditions to measure a person's blood pressure comprising detecting a bio signal plateau conversant with blood pressure measurement and initiating a blood pressure measurement. Most preferably the wearable medical device comprises; an ECG unit; a photoplethysmography unit; an accelerometer and gyroscope unit; thermal sensor; an electric air pump; a blood pressure cuff; a secure wireless communication unit; a battery pack; an inductive charging unit; a display screen; and a patient communication system. In one embodiment the wearable medical device determines a person's blood pressure readiness comprising the steps of; ensuring the patient is seated with their arm in the correct position; acquiring signals from a person's heart activity and vascular system; acquiring bioimpedance; acquiring a skin temperature measurement of the person at the site of the device; removing noise and unwanted transitory signals; identifying the ECG peaks; identifying the PPG peaks; calculating the pulse transit time; calculating the heart pulse rate; determining the polynomial fitting of the interpeak durations; and determining the standard deviation of interpeak durations for the temporal window of analysis signalling that blood pressure measurement can commence. In a preferred embodiment the wearable medical device takes a blood pressure measurement when a bio signal plateau conversant with blood pressure measurement has been detected. Brief description of the drawings Fig 1 is an illustration of the Medical Assessment System of the present invention; Fig 2 is an illustration of the Central Station of the Medical Assessment System of Fig. 1; Fig. 3 shows a patient in position in front of the Central Station as shown in Fig. 2; Fig. 4 is an illustration of a wearable medical device of the invention showing (a) the outer side and (b) the inner side of the device; Fig. 5 shows a patient receiving the wearable medical device of Fig 4 from a Central Station of the Medical Assessment System of the invention; Fig. 6 shows a patient returning a wearable medical device after use to the Central Station; Fig. 7 is an illustration of the internal modules of the Central Station according to the invention; Fig. 8 is an illustration of the pathway the wearable medical device follows through the Central Station; Fig 9 is an illustration highlighting the cleaning sections and the conveyance of a wearable medical device through the Central Station Medical Assessment System of the invention; Fig 10. is a block diagram of the Blood Pressure Measurement Readiness system according to one embodiment of the invention; Fig 11 is a flow chart of showing the determination of whether a patient is in a blood pressure measurement readiness condition using the Blood Pressure Measurement Readiness system of the invention and the actions taken if the conditions are or not satisfied with manual override and WAIT TIME override features; Fig 12 is a block diagram of the Control and Sensing section of the blood pressure measurement readiness system of Fig. 10; Fig 13 is a block diagram of the Blood Pressure Measurement section of Fig. 10; Fig 14 is a photoplethysmography (PPG) bio-signal on which an algorithm is executed to determine the hearts QRS complex peaks during ventricular excitation; Fig 15 is an PPG interpeak chart illustrating how heart rate change can be analysed during the course of a PPG measurement; Fig 16 is an electrocardiogram (ECG) bio- signal on which an algorithm is executed to determine the hearts QRS complex peaks during ventricular excitation; and Fig. 17 is an illustration of a wearable medical device (a) and in position on a person's arm (b) according to the invention. Detailed description The present invention provides a Medical Assessment System that measures a patient's bio signals and determines whether the patient is ready for a non-invasive systemic blood pressure measurement to be taken. If ready a cuff-based blood pressure measurement in a wearable medical device is activated. The medical assessment combines a number of tasks to determine a number of bio-signals that objectively initiate a blood pressure measurement based on the readiness of the patient for such a measurement. It also takes into consideration the general demeanour and observable state of a patient. The present invention also provides a method to determine whether the patient is ready for a non-invasive systemic blood pressure measurement to be taken, the method reliably determines a person's blood pressure measurement readiness prior to obtaining a blood pressure measurement by detecting a bio signal plateau conversant with blood pressure measurement. The medical assessment system of the invention comprises a reusable photoplethysmography (PPG) sensor, electrocardiogram (ECG) sensor, radial artery blood pressure measurement, weighing scales, infrared thermal sensor, laser height sensor to measure vital signs (blood pressure, respiration rate, heart rate, SpO2 (oxygen saturation), temperature and height and BMI in a primary healthcare centre. The need to measure blood pressure and other bio signals in a controlled and repeatable manner prior to consultation is important both from a manpower and clinical accuracy perspective. The combination of patient usability and clinical accuracy, precision and in particular reliability represents a paradigm shift in healthcare. Typically, non-clinic user operated health monitoring devices are not regularly calibrated and as such have an inherent lack of reliability. In addition, hospital vital signs equipment require healthcare professionals in order to operate the equipment. The medical assessment system of the present invention provides a significantly improved means to detect and measure bio signals. The medical assessment system of the present invention provides a significant change in healthcare practice as it automates the measurement of biosignals that is typically required to be manually carried out by healthcare personnel. The medical assessment system of the present invention provides for precision, accuracy and repeatability when measuring patient health. It ensures precision, accuracy and reliability in the reading of a person's blood pressure. It provides an improved system for determining the optimum time to measure a patient's blood pressure. The medical assessment system comprises a standalone unit intended to be located in a healthcare setting such as a GP surgery, clinic or the like. The medical assessment system is intended to be easily used by a patient without the need for any healthcare assistance. The system issues visual, haptic and auditory instructions for the user and all medical data is securely transferred to an Electronic Healthcare Record System for the GP or doctor to access. The system conveys the measured bio signal data to the clinician in advance of a consultation. The medical assessment system of the invention comprises a calibrator 1, and central station 2 and a reuseable wearable medical device 3. The central station unit 2 comprises a touch screen visual display 4, a thermometer 5, a height measurement device 6, a weigh mat 7, an RFID scanner 8 and a patient communication system. The unit may have a speaker unit. The central station 2 comprises a computer system and a plurality of device enclosure modules and means for receiving, conveying and dispensing a reuseable wearable medical device 3. The central station 2 comprises an opening 10 to dispense the wearable medical device 3 and an opening 11 for receiving the wearable medical device 3 after use. The central station 2 comprises a number of removable enclosure modules. Each module may be accessed and easily removed for maintenance or exchangeable for new modules as required. The removable enclosure modules are stackable and modular. The different modules comprise a receiving module 20, an inspection module 21, an isolation module 22, a pre cleaning queue module subsection 23, a first cleaning module 24, a second UV cleaning module 25, a functional assessment and charging module 26, a clean device storage module 27, a device maintenance holding module 28 and a dispensing module 29. In use a patient approaches the central station 1. The touch screen 4 communicates with the patient and instructs the patient on how to use the system. The RFID scanner 8 scans the patient's identification. The unit takes the patient's vitals, recording the patient's weight, height and temperature. The central station 2 then dispenses a reuseable wearable medical device 3 to the patient through the opening 10. The touch screen 4 communicates with the patient and instructs the patient on how to attach the wearable device 3 correctly on their arm. The touch screen 4 instructs the patient to sit and relax and be still while the wearable device 3 is in position on their arm. The wearable device 3 comprises an inflatable cuff 12, securing means 13 for correctly attaching and securing the cuff to a patient's arm, and tensioning means 15. The cuff 12 is designed to accommodate a wide range of sizes and is easily adjusted by the user to the required size. Any suitable means may be used for securing and adjusting the fit of the cuff on a patient's arm. The wearable device 3 comprises a visual user interface 14 with clear instructions given on the correct positioning of the cuff on a patients arm. The visual user interface also comprises an electrical ECG contact 16 and a controller unit 18 comprising a pump, battery and sensors. The wearable device 3 comprises a PPG sensor, ECG sensor, radial artery blood pressure measurement (cuff &transducer), thermal sensor, accelerometer and gyroscope. The cuff Inflates following correct positioning on a patients' arm. The sensing elements in the wearable medical device 3 determine whether the patient is in a Blood Pressure Measurement Readiness state and when in a readiness state initiate a blood pressure measurement using the conventional cuff based oscillometric blood pressure measurement on the wearable medical device 2. Afterthe blood pressure measurement has been taken the cuff 12 automatically deflates and the patient is instructed to return the wearable device 3 to the central station 2. The patient returns the wearable device 3 into the opening 11 in the central station 2. Once returned to the central station 1 data from the wearable medical device 3 is communicated and uploaded to the central station 1 where it is analysed and interpreted and transferred to the surgery or clinic database for the medical healthcare professional to review. Returning the wearable medical device 3 to the central station 1, the patient attaches the device3 to a holding rail 14. The wearable medical device 3 is then conveyed through the different enclosure modules in the central station 2. The holding rail 14 holding the wearable medical device 3 passes through each of the modules. The medical device 3 is transported from the receiving module 20 into the inspection module 21. Here the medical device 3 is inspected for any debris and if very soiled is guided towards the isolation area 22 for intensive off-site cleaning. Otherwise, the medical device continues to the pre cleaning queue module subsection 23 before being subjected to physical cleaning and disinfection. The first cleaning module 24 where the device is physically cleaned uses rotating rollers or brushes orthe like and suitable sterile cleaning materials. The device 3 is then passed on to the second cleaning module 25 where it is subjected to UV to disinfect the reuseable device. The device 3 is then guided through the functional assessment and charging module 26, a communications module 26 where the medical data measurements in the wearable medical device 3 is securely communicated to the central station 2 and a clean device storage module 27, ready to be passed to the dispensing module 29. If the device is deemed not functioning correctly it is moved to the device maintenance holding module 28 to be taken away for re-calibration. Calibration by the calibrator 1 may take place on site or off-site. The communications module is contained within the Central Station 2 and comprises means to receive data from the wearable medical device 3 and communicate with an Electronic Healthcare Record System. The use of the medical assessment system of the present invention gives healthcare staff time to work on other tasks as the medical assessment system does not require any healthcare personnel interaction. It is a patient led experience. The patient interacts directly with the system and follows detailed instructions on how to proceed and obtain a more accurate and reliable blood pressure reading. There is no established medical term which describes the desired state of a person when Blood Pressure (BP) measurement preparatory conditions are satisfied, the rest period completes and transitory conditions such as white coat hypertension, masked hypertension and other temporal stresses, (environmental, psychological, physiological, etc.) are not affecting the examinee. Medical terms such as homeostasis and dominance of the parasympathetic nervous system do not accurately describe the state required for reliable blood pressure measurement. One study (Gordon, T) describes subjects waiting 45 minutes before taking blood pressure measurements and state, "The usual procedure is to try to have the examinee calm and rested before measurement but the specific program for arriving at this state is highly variable." Later, in the same report the concept of resting blood pressure is introduced without definition. In more recent literature, (Brady et al) they state, "For decades, national and international hypertension guidelines have recommended that patients rest for 3 to 5 minutes before initiation of BP measurements". From such a statement it might be assumed that the goal is to have an "examinee calm and rested before measurement" but no objective measurement statistics are provided to distinguish whether a person is calm and rested or not. Blood Pressure Measurement Readiness is a term taken herein to mean a state where a patient is ready to give an accurate blood pressure measurement when they are prepared correctly and their measurements are within the required range as outlined by the WHO. The World Health Organization stipulate the following instructions when preparing a patient for a blood pressure measurement in a clinical setting. Ask the patient to empty their bladder and to abstain from caffeine, nicotine and exercise for 30 minutes before the BP measurement; Ask the patient to relax and to sit on a chair with their feet on the floor, legs uncrossed, back supported, ideally for at least 5 minutes; Neither the patient nor the observer should talk, read or use electronic devices during the rest period or during the assessment. Following the standard WHO protocol but excluding the temporal requirement, Blood Pressure Measurement Readiness is taken herein to be a state where the patient satisfies at a minimum the following conditions: Successive ECG R-R peaks temporal measurements over a 20 second window do not exceed a contextual number of standard deviations; Once a patient's measurements are within the desired conditions and ranges a reliable, precise and accurate blood pressure measurement may be initiated. In order to ensure greater confidence and reliability the following steps may also be utilised PPG LEDs used to compute pulse transit time in conjunction with ECG readings; Temperature Sensor reads within standard range for contextual measurement; Bio Impedance contextual calculations; and Accelerometer and gyroscope monitoring to ensure the patient is seated with their arm in the correct position using common human tracking approaches. The term contextual is taken herein to refer to data collected that provides insight into a patient's health beyond traditional clinical or measurement parameters. Blood pressure measurement readiness is determined by detecting Electrocardiogram (ECG) and photoplethysmography (PPG) bio signals, hand to hand bioimpedance and temperature as a context measurement, monitoring the ECG QRS and PPG systolic peaks and measuring the pulse transit time using the PPG and ECG data. The blood pressure measurement readiness assessment comprises the steps of acquiring signals from a person's heart activity and vascular system, removing noise and unwanted transitory signals, identifying the ECG peaks, identifying the PPG peaks, calculating the pulse transit time from the ECG and PPG data, calculating the heart pulse rate by subtracting successive peaks to discover the interpeak time, determining the polynomial fitting of the interpeak durations and determining the standard deviation of interpeak durations for the temporal window of analysis. The interpeak values are calculated by selecting a window over which the measurement will be calculated. The standard window is 20 seconds, so that the patient must wait until the first sample time completes. The R peaks in the window of data are identified and the interpeak values are the difference between each successive R peak as shown in Fig. 16. An array of interpeak data is deduced and stored. The interpeak period sample standard deviation or BP Measure Trigger can be calculated: Jyy. (interpeak distance,- — interpeak array mean)2 —------------------------------— N - 1 As each sample set is analysed, time elapsed and another set of data is acquired after a time period. The standard time period is one second. The array of BP Measure Trigger values may also be used as context measurements to initiate a blood pressure measurement. Using data analysis when the dynamic blood pressure measurement conditions are met a bio signal plateau conversant with blood pressure measurement is detected and the system signals that a blood pressure measurement can commence. The blood pressure measurement readiness and trigger system comprise a control and sensing section 101 and a blood pressure measurement section 102 (Fig. 10). Fig. 11 is a flowchart illustrating the requirements to begin the process of detecting blood pressure measurement readiness and includes a Time Out or Override function. The control and sensing section 101 has a series of sensor elements comprised of electrodes 118, LED &photodiodes 119, temperature sensor 120 and accelerometer and gyroscope 134. Signals are acquired via these sensors and passed via analog frontends 136,122,123 or direct connection as illustrated in this instance by the gyroscope and accelerometer 134, to the Central Processing Unit (CPU) 129. A display unit 128 guides a patient through the steps required for a blood pressure measurement. The display unit 128 may issue a visual alert if the accelerometer and gyroscope unit 134 communicates data to the CPU 129 indicating that the patient is moving or the device position does not comply with WHO guidelines after the measurement process has been initiated. The speaker and haptic unit 133 may also be used to alert the patient to these errors. The control and sensing section operation unit 135 includes a power button 130, measurement button 131 and override button 132 which may enable a user to control the measurement device. The override button 132 enables a user to skip the measurement readiness analysis and take a measurement, in which case the activation of the override function is recorded against the measurement. On successful detection of a state conversant with blood pressure measurement, the Trigger BP measurement section 125 sends a signal to the blood pressure measurement section 102. The blood pressure measurement section 102 comprises a cuff 103 containing an air bladder. The air bladder is inflated by means of a pump attached to a pneumatic connection 105 to the air bladder 104. The blood pressure measurement section follows a standard approach to oscillometric blood pressure measurement and comprises a pump 107, exhaust 106 and pressure sensor 108 used to determine the mean arterial pressure, systolic and diastolic blood pressure of a human being. In one embodiment of the invention, the microcontroller unit (MCU) 113 receives the trigger signal from the control and sensing section 101, the blood pressure measurement control section 117 then communicates with the pump motor control 100 to inflate the cuff 103 using the pump 107. The pressure sensor 108 signal is amplified 111 and filtered 112 before being converted to a digital signal in the A / D conversion section 116. The digital signal is analysed in the blood pressure computation section 115 and the blood pressure measurement control section 117 ceases the pump action and signals the valve control 109 to Exhaust 106. The communication Section 114 then transmits the measurement data to the control and sensing section 101 CPU 129 where it may be stored using the data storage section 127 or transmitted to an Electronic Health Record System via the communication section 126. In another embodiment the invention provides an independent standalone wearable medical device for easy-to-use blood pressure measurement readiness assessment and once correct conditions are met commences a blood pressure measurement. The wearable medical device 3 comprises a Control and Sensing Section and a Blood Pressure Measurement Section both of which are connected by common electrical ground and communication protocols. As shown in Fig. 17 (b) the device 3 may be positioned on the arm 203 of a person with a sensor array 202 making skin contact. A contact with the ECG electrode 201 from the opposite side of the body on which the device is worn is required to close the electrical cardiac loop. A clasp 203 or any other suitable means secures the device in place and either the radial or brachial artery on the arm is occluded by the cuff to determine a person's blood pressure. The invention is not limited to the embodiments hereinbefore described, with reference to the accompanying drawings, which may be varied in construction and detail. References Boniol et al "The global health workforce stock and distribution in 2020 and 2030: a threat to equity and 'universal' health coverage?" BMJ Global Health 2022 Hayes E, Gannon L &Quinlan D "Sepsis and documentation of six physiological vital signs in GP 5 Out of-Hours" Ir Med J; 2023 Dall'Ora, C. et al. (2021a) 'How long do nursing staff take to measure and record patients' vital signs observations in hospital? A time-and-motion study', International Journal of Nursing Studies, 118 WHO technical specifications for automated non-invasive blood pressure measuring devices with 10 cuff. Geneva: World Health Organization; 2020 Levy J, Gerber LM, Wu X, Mann SJ. Nonadherence to Recommended Guidelines for Blood Pressure Measurement. J Clin Hypertens (Greenwich). 2016 Nov;18(ll):1157-1161 Nuredini G, Saunders A, Rajkumar C, Okorie M. "Current status of white coat hypertension: where are we?" Ther Adv Cardiovasc Dis. 2020 Jan-Dec;14 15 Gordon, Tavia (1964). Blood pressure of adults by age and sex; United States, 1960-1962. (4). Brady et al (2021), "Effects of Different Rest Period Durations Prior to Blood Pressure Measurement: The Best Rest Trial" Hypertension. 2021;78:1511-1519. DOI: 10.1161 / HYPERTENSIONAHA.121.17496.

Claims

1. A medical assessment system comprising a central station, a reuseable wearable medical device and a calibration system.

2. A medical assessment system as claimed in claim 1 comprising means for measuring weight, height, bioimpedance and vital signs including blood pressure, heart rate, respiration rate, peripheral oxygen saturation and core temperature.

3. A medical assessment system as claimed in claim 1 or 2 wherein the central station engages with a user, directs the user to login, measures their height and weight, measures their temperature, dispenses a wearable medical device to the user and receives the wearable medical device after use.

4. A medical assessment system as claimed in any preceding claim wherein the central station comprisesa computer system;a display screen;a temperature measurement unit;a weight measurement unit;a height measurement unit;a patient communication system;a plurality of device enclosure modules; andmeans for receiving, conveying and dispensing a reuseable wearable medical device.

5. A medical assessment system as claimed in claim 4 wherein the computer system comprises a microprocessor, RAM, wireless cellular communication, capable ofcommunicating with the wearable device receiving and transmitting medical data to an Electronic Healthcare Record (EHR) system.

6. A medical assessment system as claimed in claim 4 or 5 wherein the device enclosure modules comprise;a receiving unit;an inspection unita cleaning unit;a functional assessment and charging unit;a communications unit; anda dispensing unit7. A medical assessment system as claimed in claim 6 wherein the cleaning unit comprises aset of rotating rollers, sterile cleaning material and UV lights.

8. A medical assessment system as claimed in any preceding claim wherein the wearable medical device comprises;an ECG unit;a photoplethysmography unit;an accelerometer and gyroscope unit;thermal sensoran electric air pump;a blood pressure cuff;a short range secure wireless communication unit;a battery pack;an inductive charging unit;a display screen;and a patient communication system.

9. A medical assessment system as claimed in any preceding claim wherein the wearable medical device comprises attachment means for securely attaching and detaching the device to a user's arm.

10. A medical assessment system as claimed in claim 8 or 9 wherein the wearable medical device detects and records ECG and PPG bio signals, measures blood pressure by occluding the radial artery and determines the user's movements and after measurement completes securely communicates the medical data to the central station.

11. A medical assessment system as claimed in claim 10 wherein the wearable medical device is conveyed through the device enclosure modules in the central station, communicates the medical data measurements in the wearable medical device securely to the central station and is cleaned and validated ready for reuse.

12. A medical assessment system as claimed in any preceding claim wherein the calibration system comprises;a physical interface that enables the wearable medical device to be calibrated;an arbitrary function generator that emits an ECG signal to the wearable medical device;means to absorb PPG light emissions and transmit expected return signals that mimic various blood oxygenation levels and heart rate patterns;a pressure transducer measuring the pressure exerted by the blood pressure cuff on the wearable medical device;a wireless interface that enables the wearable medical device to be recalibrated; anda physical interface that enables the wearable medical device to be recalibrated.

13. A method for determining the optimum conditions to measure blood pressure using the medical assessment system as claimed in any preceding claim comprising detecting a bio signal plateau conversant with blood pressure measurement and initiating a blood pressure measurement.

14. A method for determining the optimum conditions to measure a person's blood pressure comprising detecting a bio signal plateau conversant with blood pressure measurement.

15. A method as claimed in claim 14 comprising the steps of;acquiring signals from a person's heart activity and vascular system;removing noise and unwanted transitory signals;identifying the ECG peaks;calculating the heart pulse rate; anddetermining the standard deviation of interpeak durations for the temporal window of analysis signalling that blood pressure measurement can commence.

16. A method as claimed in claim 14 and 15 comprising the additional steps of;acquiring bioimpedance;acquiring a skin temperature measurement of the person;identifying the PPG peaks; andcalculating the pulse transit time.

17. A method as claimed in claim 14 to 16 comprising the additional steps of;determining the polynomial fitting of the interpeak durations.

18. A method as claimed in claim 14 to 17 comprising the step of initiating a blood pressure measurement when a bio signal plateau conversant with blood pressure measurement has been detected.

19. A wearable medical device for determining the optimum conditions to measure a person's blood pressure comprising detecting a bio signal plateau conversant with blood pressure measurement and initiating a blood pressure measurement.

20. A wearable medical device as claimed in claim 19 comprising;an ECG unit;a photoplethysmography unit;an accelerometer and gyroscope unit;thermal sensor;an electric air pump;a blood pressure cuff;a secure wireless communication unit;a battery pack;an inductive charging unit;a display screen; anda patient communication system21. A wearable medical device as claimed in claims 19 or 20 wherein the device determines a person's blood pressure readiness comprising the steps of;ensuring the patient is seated with their arm in the correct position;acquiring signals from a person's heart activity and vascular system;acquiring bioimpedance;acquiring a skin temperature measurement of the person at the site of the device;5 removing noise and unwanted transitory signals;identifying the ECG peaks;identifying the PPG peaks;calculating the pulse transit time;calculating the heart pulse rate;10 determining the polynomial fitting of the interpeak durations; anddetermining the standard deviation of interpeak durations for the temporal window of analysis signalling that blood pressure measurement can commence.

22. A wearable medical device as claimed in any of claims 19 to 21 wherein the device takes a15 blood pressure measurement when a bio signal plateau conversant with blood pressuremeasurement has been detected.T +44(0)30 0300 2000Search report under Section 17 of the Patents Act 1977Application No.: GB2509244.6Claims searched: 1-13Date search completed: 23rd September 2025International classificationSubclass and subgroup Valid from A61B5 / 021 01 / 01 / 2006 A61B5 / 022 01 / 01 / 2006 A61B5 / 024 01 / 01 / 2006 G07F7 / 06 01 / 01 / 2006Field of searchWorldwide search of patent documents classified in the following areas of the IPC: A61B, G07FDatabases used in the preparation of this search report:SEARCH-PATENTDocuments considered to be relevantPatent literatureCategory Relevant to claims Document of relevance X 1-7 US 11266476 B1 (WILLIS et al.) - See Figures 4-8 and their descriptions and Lines 4-23 of Column 12 X 1-11 CN 216876363 U (YANG et al.) - See Figures and their description X 1-7 US 2022 / 0233241 A1 (SHELTON et al.) - See Figures 1A and 2A-C and their descriptions X 1-7 CN 111341426 A (BAI et al.) - See Figures and their description X 1-7 US 5337290 A (VENTIMIGLIA et al.) - See Figures and their description X 1-7 US 11470987 B1 (GOMEZ) - See Figures and their descriptionsT +44(0)30 0300 2000Non-patent literature[None]CategoriesLetter or symbol Description X Document indicating lack of novelty or inventive step. Y Document indicating lack of inventive step, if combined with another document of the same category. & Member of the same patent family. A Document indicating technological background. P Document published on or after the priority date but before the filing date of the present application. E Earlier application published on or after the filing date of the present application.T +44(0)30 0300 2000Further Search report under Section 17 of the Patents Act 1977Application No.: GB2509244.6Claims searched: 14-22Date search completed: 11th March 2026International classificationSubclass and subgroup Valid from A61B5 / 021 01 / 01 / 2006 A61B5 / 022 01 / 01 / 2006 A61B5 / 024 01 / 01 / 2006 G07F7 / 06 01 / 01 / 2006Field of searchWorldwide search of patent documents classified in the following areas of the IPC: A61BDatabases used in the preparation of this search report:SEARCH-PATENTDocuments considered to be relevantPatent literatureCategory Relevant to claims Document of relevance X 14-22 WO 2021 / 019059 A1 (KONINKLIJKE PHILIPS NV) - See Figures 1-6, their descriptions, and Pages 18 and 19 X 14-22 US 2023 / 0320602 A1 (BIOINTELLISENSE INC.) - See Figures 1-6, their descriptions, and Paragraph 0011 X 14-22 US 2021 / 0068843 A1 (TECHNO SCIENCE CO. LTD.) - See Figures 5-7 and their descriptions X 14-22 US 8251913 B2 (OMRON HEALTHCARE CO. LTD. et al.) - See Figure 10 and its descriptionT +44(0)30 0300 2000X 14-22 JPH 09299339 A (OMRON TATEISI ELECTRONICS CO.) - See Paragraphs 0005 and 0006 X 14-22 US 2024 / 0312584 A1 (PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO. LTD.) - See Figures 10-14 and their descriptionsNon-patent literature[None]CategoriesLetter or symbol Description X Document indicating lack of novelty or inventive step. Y Document indicating lack of inventive step, if combined with another document of the same category. & Member of the same patent family. A Document indicating technological background. P Document published on or after the priority date but before the filing date of the present application. E Earlier application published on or after the filing date of the present application.

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