Apparatus and method for measuring blood pressure and other vital signs via a finger

Abstract

A vital sign measuring device and method for obtaining an indication of a human blood pressure through a finger are provided by an inflatable measuring bladder adapted to contact only a portion of the underside of a human finger that constitutes the finger pad. A structure or other instrument applies a downward force to the top portion of the finger opposite the finger pad. Blood pressure can be measured without using any electromagnetic radiation, for example, without using miniature dynamic light scattering (mDLS). Devices and methods for obtaining indications of other vital signs are also disclosed, such indications including hematocrit value and total protein amount.

Description

Technical Field

[0001] The present disclosure generally relates to systems and methods for measuring the blood pressure of animals, particularly humans, via a finger path, either alone or in combination with one or more other non-blood pressure vital signs, such as hematocrit value, total protein amount, blood glucose level (blood sugar level), SpO2, pulse rate, respiratory rate, body temperature, EEG, and others. In particular, the present disclosure relates to improved methods and devices for accurately measuring blood pressure via a finger, either alone or in combination with other vital signs.

[0002] [Citation of Related Applications] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 365,818, filed on June 3, 2022, entitled "Apparatus and Method for Improving Blood Pressure Measurement Via a Finger" (hereinafter, the "Provisional Application"). This provisional application is hereby incorporated by reference in its entirety and made a part of this specification.

[0003] Subject to the following description and certifications, the following U.S. patents and U.S. patent application publications (hereinafter collectively referred to as "references") are also incorporated by reference in their entirety and made a part of this specification. The subject matter of the references that is contrary to the present disclosure shall not be made a part of this specification. The claims of the references shall not be made a part of this specification. If there is a conflict between the present disclosure and the references, the references shall be considered complementary to the present disclosure, and in the event of any irreconcilable conflict, the present disclosure shall prevail. The specification shall incorporate the information of the references only to the extent that no conflict will arise between such information and the present disclosure. Where a conflict might invalidate the description of any claim of the present disclosure, the information that gives rise to such conflict shall not be specifically cited. The above disclaimer does not apply to provisional applications. The references are U.S. Patent Nos. 8,950,935; 10,492,684; 10,485,431; and 11,504,014, and U.S. Patent Application Publication No. 2018-0235479A1.

Background Art

[0004] As used herein, the terms "monitor (verb) / monitoring (noun)", "measure / measurement", "capture / capture", "detect / detection", and "sense / sensing" are used synonymously, provided that there is no other indication in the context. Similarly, the terms "user", "human", "patient", "pulse rate", "heart rate", "pulse oximeter", "SpO2", "pump", "pneumatic engine", "physiological characteristic", "vital sign" are used synonymously, provided that there is no other indication in the context. Accordingly, subject to the above exceptions, such terms may be considered to be used interchangeably throughout.

[0005] The specification of U.S. Patent No. 11,504,014 of the above-mentioned common assignee, which is incorporated herein by reference (hereinafter referred to as the " '014 Patent"), discloses an apparatus and method for measuring blood pressure and other vital signs through a finger. The blood pressure measurement system disclosed in the '014 Patent specification employs a circular inflatable measurement bladder that receives the entire circumference of a portion of the finger and, when inflated, substantially completely encloses and substantially contacts and compresses it, such that in obtaining a blood pressure reading, it does not require the use of light, a light sensor, or optical measurements, nor does it require the use of any other form of electromagnetic radiation (or its measurement method). However, it has been found that in order to improve the accuracy of blood pressure measurements taken through a finger, it may not be necessary to use an inflatable measurement bladder that completely surrounds or completely contacts and completely compresses the entire circumference of the finger. In particular, blood pressure measurements are unexpectedly and dramatically improved when the inflatable measurement bladder is configured to contact only the bottom portion of the finger and a force or pressure is applied to the top of the finger to press the finger towards the inflatable measurement bladder while the blood pressure reading is being taken.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

[0007] A vital sign measuring device (VSMD) for measuring blood pressure through a finger is disclosed. The VSMD has an arcuate inflatable blood pressure measuring bladder that is adapted to contact only partially the surface of the finger, specifically, not the entire surface of the finger but at least the surface of the finger pad on the underside of the finger. The bladder is provided in an arcuate cradle that is coupled to a base housing an inflation pump, a relief valve, a pressure sensor, a microprocessor, and circuitry for controlling the pump and valve and processing signals from the pressure sensor. During the blood pressure measurement cycle, the bladder does not completely enclose the finger, or does not sufficiently compress or contact the entire perimeter of the finger. Rather, the bladder contacts only a portion of the underside of the finger.

[0008] As used herein, the term "structure or other instrument" (SOI) and similar terms refer to a structure associated with or integral to the overall measuring device described herein for applying a force or pressure to the top of the finger, or a structure of an instrument separate from and / or independent of the overall measuring device for applying such force or pressure. As disclosed herein, the SOI is employed to press the finger pad against the corresponding portion of the bladder. The SOI enhances the contact between the digital artery in the finger pad and the corresponding portion of the bladder and reduces or eliminates movement of the finger relative to the bladder during the measurement cycle. Patent No. 014 describes how to analyze the vibration measurement signal provided by a pressure sensor that reads the bladder pressure to obtain a blood pressure indication. The present disclosure calculates a blood pressure indication using the same vibration measurement signal. The same blood pressure measurement algorithm as disclosed in Patent No. 014 can be employed in the context of the present disclosure. Using the SOI, the amplitude of the vibration measurement signal measured by the pressure sensor significantly increases, and noise and other artifacts that might otherwise occur are reduced, resulting in a significant increase in the signal-to-noise ratio (SN ratio) and enabling more accurate and reproducible systolic and diastolic blood pressure measurements.

[0009] The VSMD can also measure the pulse rate via a vibration measurement signal. In obtaining the indication of blood pressure or pulse rate, the use of light, an optical sensor, optical measurement, or the use of any other form of electromagnetic radiation (or its measurement method) is unnecessary.

[0010] In addition to blood pressure measurement via the finger pulp, VSMD embodiments are also disclosed that include a physiological light monitoring system (PLMS) for further measuring one or more of the following non-blood pressure vital signs: blood glucose level, heart rate variability, respiratory rate (breathing rate), SpO2, blood flow rate, total hemoglobin (SpHb), PVi, methemoglobin (SpMet), acoustic respiratory rate (RRa), carboxyhemoglobin (SpCO), oxygenation reserve index (ORi), oxygen content (SpOC), hematocrit value (Hc), total protein amount (TP), EEG, and temperature. Details of the PLMS can be found in the specification of Patent No. 014.

[0011] The display can provide a visual indication of the vital signs. It can generate a health score to display the data and send the data to a smartphone equipped with an app for sending the vital sign data to a remote patient monitoring system.

[0012] The following description of the drawings relates to various embodiments of an apparatus, system, and method for embodying a VSMD that employs an SOI for measuring blood pressure via the finger pulp and a PLMS for measuring vital signs other than blood pressure as an option, and is not intended to limit the scope of the disclosure and / or invention described herein, except for the disclosure content and / or invention recited in the appended claims.

Brief Description of the Drawings

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BEST MODE FOR CARRYING OUT THE INVENTION

[0014] Referring to the drawings (wherein like reference numerals represent like elements), FIG. 1 shows an embodiment of the VSMD100 for measuring blood pressure and heart rate. The VSMD100 has a cradle 102 attached to a base 104. The cradle 102 has a rigid arcuate portion 106 (which forms a circle that does not reach a complete circle in the embodiment of FIG. 1), to which an arcuate inflatable bladder 108 of the same shape and thus corresponding thereto is attached. The cradle is adapted to receive the bottom portion of the finger constituting the finger pads F1, F2 or F3 (see FIG. 3), such that the finger pads rest on the outer surface of the inflatable bladder. A strap 110 constitutes the SOI. The proximal end 110' of the strap is attached to the cradle and the distal end 110'' remains slack. The strap or a portion thereof preferably has a surface fastener (also called a hook-and-loop fastener), such as Velcro®.

[0015] As shown in FIGS. 4A and 4B, a hose connection portion 148' provided within the base 104 enables air communication with the bladder 108. The base 104 also houses an inflation pump 144 that controllably inflates the bladder via an air hose 148, a pressure sensor 140 that provides an indication of the bladder pressure applied to the finger pad, and a relief valve 142 that controllably deflates the bladder via the air hose 148. The base also houses a circuit portion including a temperature sensor 120 (e.g., an infrared sensor, a thermopile, or a thermocouple) that measures the body temperature at the finger, and a microprocessor 146. The microprocessor receives the pressure sensor and temperature data, controllably operates the pump and the relief valve, and, as described in more detail below, in the 014 patent specification, uses an algorithm to calculate blood pressure and body temperature measurements, and, if desired, the pulse rate, and is operatively coupled to and / or interfaced with the pump, the pressure sensor, the relief valve, and the temperature sensor (and other sensors, switches, and control devices disclosed herein). A USB communication port and / or a wireless communication circuit (e.g., Bluetooth) 116 may be provided to facilitate firmware updates and / or offload data from the VSMD to another device, such as a smartphone, and / or a device, such as a remote patient monitoring system (RPMS). A power button 108 may be provided to turn the power of the instrument on / off and / or start a blood pressure measurement cycle. An LED 119 may be able to display the power state (on / off) of the VSMD. A proximity sensor (not shown) may be employed to detect the presence of a finger on the bladder and prevent inflation of the bladder if the finger is not placed on the bladder. The cradle 102 and the base 104 may be made of a molded thermoplastic material. The bladder 108 may be made of an elastic airtight material, such as silicon, nylon, latex, rubber, etc. The measurement may be performed at any of the finger pad portions F1, F2, F3 of the finger F shown in FIG. 3.As shown in FIG. 2, a display for displaying systolic blood pressure, diastolic blood pressure, pulse rate, and any other desired characteristic to be measured may be provided below the base 104 of the VSMD100.

[0016] FIG. 4B shows the finger pad portion F2 of the finger F located within the cradle 106 and resting on the top (outward-facing portion) of the bladder 108. As shown, the strap 110 is disposed over the corresponding portion of the top of the finger F, and the fastening portion 112 at its distal end 110″ is attached to a mating portion (not shown) provided on the side of the cradle opposite the side to which the proximal end 110′ of the strap is attached. As a variant, the cradle may have a slotted structure 107 provided on the side opposite the attached strap portion 110′. In such a case, the strap 110 is, as is well known, looped around the finger F, passed through the slot of the structure 107, and then folded back and fastened to itself. The strap should be tightened only slightly on the finger if necessary to prevent movement of the finger relative to the bladder and to secure the finger within the cradle. As will be appreciated, as indicated by the arrow 115, upon inflation of the bladder 108, pressure is applied only to a portion under the finger, for example the finger pad F2, because the finger is constrained relative to the bladder by the strap 110, thereby enabling blood measurement through the finger pad.

[0017] As a result of the cradle 102, bladder 108 and strap 110 and the circuitry and algorithms described herein and in Patent No. 014, it is not necessary to employ measurement techniques using electromagnetic radiation (EMR), and such measurement techniques include measurement techniques using lasers that employ EMR reflection and / or transmission measurements to measure blood pressure or other light (e.g., mDLS). By combining such a structure with the use of the oscillometric method described herein to analyze the pressure data within the bladder, blood pressure can be measured with substantially higher accuracy than in the case of the embodiments disclosed in Patent No. 014 or any other known prior art system for measuring blood pressure via a finger. Supplementary EMR-utilizing measurements, which would mean improving the accuracy of blood pressure and pulse rate measurements, are not required.

[0018] As shown in FIG. 1, the cradle may be preferably attached to or integral with the base. However, the cradle may be separate from the base and may be coupled to the base via the air hose 148' and any other electrical connections that may be required to measure other characteristics, such as temperature or other characteristics measured by the PLMS. As a variant, the cradle may not be used at all, and the bladder may be attached to the finger by a strap, such as the strap 110, with the result that the bladder comes into contact with the finger pad. The strap may be tightened only if necessary to prevent the bladder from moving relative to the finger.

[0019] Figures 5, 6, and 7 show the VSMD200 that employs both the above-described blood pressure measurement system and the PLMS204, and both the blood pressure measurement system and the PLMS are attached to the base 202. The PLMS can calculate vital signs and physiological characteristics, such as blood glucose level, heart rate variability, respiratory rate, peripheral oxygen saturation (SpO2), blood flow rate, total hemoglobin (SpHb), pulse wave variability index (PVi), methemoglobin (SpMet), acoustic respiratory rate (RRa), carboxyhemoglobin (SpCO), oxygenation reserve index (ORi), oxygen content (SpOC), EEG, hematocrit value (Hc), and total protein amount (TP) as described in the specification of Patent No. 014. If desired, the PLMS can also be used to calculate the heart rate. The base preferably has a display for displaying one or more of the vital signs / physiological characteristics. Measurements are performed after inserting the human finger F into the cavity or void 208 of the PLMS until the fingertip reaches the fingertip stop 226 (Figure 6). The reference provides further details on how such a structure can be embodied and how such measurements can be performed.

[0020] As shown in Figure 6, the PLMS is provided with an emitter 220 and an emitter / detector 222 that emits / detects light as described below to obtain data for calculating these vital signs and physiological characteristics. The emitter 220 and the emitter / detector 222 are employed for transmission light measurement (i.e., to measure the light emitted from the emitter 220, transmitted through the fingertip, and then detected by the emitter / detector 222), while only the emitter / detector 222 is employed for reflection light measurement (i.e., to emit light and measure the light reflected from the fingertip).

[0021] The emitter 220 preferably emits light in two ranges, a. Configuration Example A: 640 nm to 680 nm (preferably, about 660 nm), and 920 nm to 960 nm (preferably, about 940 nm). b. Configuration Example B: A continuous emitter from 200 nm to 1200 nm. c. Configuration Example C: Twelve separate emitters of specific frequencies in the range from 200 nm to 1200 nm.

[0022] The emitter detector 222 preferably emits light in three ranges. a. Configuration Example A: 300 nm to 415 nm (preferably, about 395 nm), 640 nm to 680 nm (preferably, about 660 nm), and 920 mm to 960 mm (preferably, about 940 mm). b. Configuration Example B: A continuous emitter from 200 nm to 1200 nm. c. Configuration Example C: Twelve separate emitters of specific frequencies in the range from 200 nm to 1200 nm.

[0023] The emitter detector 222 preferably detects light in the range from 200 nm to 1200 nm.

[0024] Preferably, the photodiode is physically arranged such that the emitter 220 is located directly above the fingernail, and the emitter / detector 222 is located directly below a part of the bottom of the finger (finger pad) under the fingernail. More details are described in the Specification of Patent No. 014 and other references. The scope of the present disclosure and the scope of the invention described in the related appended claims are not limited to the above emitter and emitter / detector configuration examples. Other configuration examples that emit or detect light within the disclosed range (or within a reasonable proximity of the disclosed range) are intended to be included in the claims, except as explicitly described herein.

[0025] As shown in FIG. 7, the base 202 of the VSMD200 may house a temperature sensor 120 that measures body temperature at the finger, EKG pads 302, 304 that measure EKG through a human fingertip, a camera module 126 that obtains an image of a portion of the skin of a human head when the VSMD200 is held next to the face, and a three-axis accelerometer 128 that detects the movement of the VSMD. The accelerometer may be used to terminate respiratory rate measurement (or other measurements) when movement is detected. The accelerometer can also be employed for fitness tracking, for example, to measure the number of steps. A power switch 118 and a USB port 116 may also be provided. The display 206 may be integrated into the base. The 014 patent specification includes further details regarding the configuration of the PLMS and the methods employed by the PLMS.

[0026] FIGS. 8 - 13 show various alternative embodiments that embody SOIs that can be employed in place of the SOI embodiment of FIG. 1.

[0027] The VSMD300 of FIG. 8A employs an SOI embodiment that includes an arcuate cap or insert 302, on which a strap 304 is placed. The cap 302 may be composed of a foam or a thermoplastic resin. The strap 304 may be a hook-and-loop strap. The finger F may be placed through a hole created by the combination of the cradle 102 and the cap 302, such that the fingertip thereof rests on the bladder surface 108 as shown in FIG. 8B. The strap 304 may be tightened and fastened in the same manner as the strap 110 of the embodiment of FIG. 1. Various caps 302 with various radii may be provided to fit various finger sizes.

[0028] The VSMD310 of FIGS. 9A - 9C employs an SOI embodiment that includes various shims 312a - 312n that can be stacked. Each of the shims 312a - 312n has a radius that is the radius of each of the preceding and subsequent shims in the stack 312. FIG. 9C shows the inclusion of the PLMS204 within the VSMD310, but this is for illustrative purposes only. Additionally, the VSMD of FIG. 9C shows a cradle 310 that is substantially 360°, i.e., substantially a complete circle, and this cradle has a cavity through which a finger F can be inserted and positioned. The finger F can also extend into the PLMS204 for vital sign measurement in addition to blood pressure measurement. The bladder 108 is positioned at the arcuate bottom portion of the cradle as in the case of FIG. 1. One or more of the shims 312a - 312n are preferably positioned on top of the finger, and then the finger is preferably inserted into the cavity with the shim on it, such that the shim is adapted to apply a downward pressure or force as described above. As a variant, the finger can first be inserted into the cavity, and then one or more of the shims 312a - 312n can be slid onto the top of the finger and into the cavity, such that the shim is adapted to apply the downward pressure or force as described above. Variants of both techniques can also be employed.

[0029] The VSMD320 of FIGS. 10A and 10B employs an SOI embodiment that includes a cap / shim 326 for applying a downward pressure / force via a strap 324 attached to a portion 326 of the VSMD. A twistable / rotatable knob 322 is preferably employed to adjust the magnitude of the downward pressure / force on the top of the finger F.

[0030] The VSMD330 of FIGS. 11A and 11B employs an SOI embodiment similar to the SOI embodiment of FIGS. 10A and 10B. A double strap 334 applies a downward force via a shim / cap 332 by rotation of a twistable / rotatable knob 338 provided on the side of the base of the VSMD330.

[0031] For each of the above embodiments, it has been found that the optimal results are achieved when the SOI is adjusted to limit the lateral movement of the finger pad to a range of about 0.4 mm to 4 mm with respect to the surface of the inflatable bladder that contacts the finger pad.

[0032] The VSMD340 of FIGS. 12A - 12C employs an SOI embodiment that includes a cradle 106 (with an inflatable measurement bladder 108 provided) and a second inflatable bladder 342 provided at the top of the cuff formed by the upper portion 344. The second bladder 342, when inflated, applies a downward pressure / force. A bolus pump 346 provided in the upper portion 344 (or provided elsewhere) may be employed to inflate the second bladder 342 prior to the start of the blood pressure measurement cycle. In one embodiment, after inserting the finger F into the cuff, the second bladder is inflated to about 10 mmHg to about 50 mmHg using the bolus pump. This is a range that has been found to sufficiently limit the movement of the finger pad with respect to the inflatable bladder. Thereafter, the inflatable bladder is inflated / deflated as described herein. A manual relief valve (not shown) may be employed to deflate the second bladder following the end of the blood pressure measurement cycle.

[0033] The SOI embodiment for the VSMD360 of FIG. 13 is conceptually similar to the embodiment of FIGS. 12A - 12C in that a second inflatable bladder is employed to apply a downward force / pressure. A syringe 362 is pneumatically coupled to the second bladder via an air hose 364. A manual valve 366 may be employed to maintain the pressure within the second bladder during the blood pressure measurement cycle and to deflate the second bladder following its end. As shown, if desired, shims 312a - 312n may also be employed as described above, notwithstanding their association with the inflation of the second bladder.

[0034] In yet another embodiment (not shown), a downward force or pressure can be applied by depressing the top portion of finger F on which blood pressure is to be measured by the fingers of the user's other hand, so that as a result, the lateral movement of the finger pad of finger F is restricted to a range of about 0.4 mm to 4 mm with respect to the surface of the inflatable bladder that contacts the finger pad.

[0035] Referring to FIG. 14, a method for determining blood pressure, i.e., systolic blood pressure (SBP) and diastolic blood pressure (DBP) as well as the pulse rate, via pressure sensor data is shown. It is preferable that the finger be inserted onto bladder 108 (500), and then after applying an appropriate downward pressure / force by SOI, the measurement begins (502). Once the measurement cycle begins, the pump inflates bladder 108 to a target pressure, which is generally at least 220 mmHg (504). Once the bladder reaches its target pressure, the relief valve is controllably opened so that the bladder pressure can linearly decrease over a period of 40 - 60 seconds (506). All of the above steps are performed under the control of microprocessor 146, which executes appropriate program code. When deflating the bladder, the microprocessor processes the raw pressure signal data over a period of time by applying a 0.5 Hz - 5 Hz filter to the raw pressure signal data to generate a plethysmogram waveform (FIG. 15A) (508). The plethysmogram waveform data is analyzed by the microprocessor to provide an indication of the heart rate (510). Next, the heart rate data is processed by the microprocessor to generate a power spectrum 518 (FIG. 16A), and then the microprocessor convolves the power spectrum as shown at reference numeral 512. Next, the microprocessor provides indications of SBP and DBP using the constant rate method (514). Next, the blood pressure and heart rate data are stored and transmitted to a subsystem located within or away from VSMD, such as RPMS, for later use (516). Thereafter, the SOI is released, removed, or deflated to allow removal of the finger.

[0036] FIG. 15A is an example showing the relationship between the vibration measurement waveform and time (seconds). FIG. 15B is an example showing the relationship between the vibration measurement waveform envelope and pressure (mmHg). The systolic blood pressure value and the diastolic blood pressure value are estimated from this data using a constant rate method.

[0037] FIGS. 16A and 16B show pressure sensor amplitude data measured with an inflatable measurement bladder during inflation and deflation, without using SOI (FIG. 16A) and using SOI in connection with, for example, the VSMD embodiments disclosed herein (FIG. 16B). As will be appreciated, the use of, for example, the embodiments described herein has significantly and substantially improved blood pressure measurement results.

[0038] FIG. 17 shows a process flow for measuring Hc and TP using the systems and methods described herein. After inserting a finger into the PLMS (810), the measurement may be started automatically by finger detection using a proximity sensor or user-initiated (812). Thereafter, the PLMS records transmission and reflection data from the detector for a period of 15 seconds or more (814). The microprocessor determines the heart rate (816) and calculates the difference between the peaks and valleys in the detected EMR data (818). Next, the microprocessor calculates Hc (820) and TP (822) as described above. Next, TP and Hc are sent to the communication subsystem (824). Further details are described in Patent Specification No. 014.

[0039] Referring to FIG. 18, a method 700 that can be used to measure blood glucose and other physiological characteristics / vital signs includes the step of receiving data from a SpO2 / glucose subsystem that includes a photodiode receiver of an ER (702). An example of the SpO2 / glucose subsystem is the PLMS204. The blood glucose value and SpO2 can be derived from the data received from the detector 222 (704, 706). The heart rate, respiratory rate, heart rate variability, and DBP can also be derived (708). It is advisable to use method 710 to detect an infrared signal representing the body surface temperature (712), receive the body surface temperature from an infrared sensor (714), and provide data, for example, the core (body center) temperature that is correlated with the body surface temperature (716). Using method 720, examine the pixel values of a plurality of images of a finger (722), obtain the movement over time of the pixel values between a plurality of images that are below a specific threshold (724), amplify the movement over time, and as a result, obtain the amplified movement over time (726), and it is advisable to visualize the blood flow pattern in the amplified movement over time of the plurality of images (728).

[0040] It is advisable to send the measured vital signs from the communication subsystem, for example, via a short-range wireless communication path (730) and / or securely (732), to the RPMS.

[0041] The measurement of Hc and TP can also employ another version of the PLMS and method 700. In this case, using the data from the 395 nm emitter reflection, TP is calculated by ratio with the data from the 940 nm emitter reflection on the side of the finger opposite to the fingernail. The hematocrit value is calculated by the following equation using the transmitted 660 nm and 940 nm signals, and in this equation, f w and f pp are parameters determined by clinical trial calibration for the patient. In the above equation on TIFF2025521184000002.tif2387, H is the hematocrit value (Hc), f wis the tissue water fraction, f pp is the crystalline protein fraction, R is the ratio of multiples of the blood pulse spectrum, μaHb(λ1) is the sum of the absorption coefficients of the two forms of hemoglobin at the first wavelength, μaw(λ2) is the absorption coefficient of water at the second wavelength, Δμs(λ1) is the difference in the scattering coefficients of blood and the surrounding tissue at the first wavelength, Δμs(λ2) is the difference in the scattering coefficients of blood and the surrounding tissue at the second wavelength, 0.34 is the fraction of the red blood cell volume occupied by hemoglobin, which is considered to be constant.

[0042] The VSMD described herein may be configured to communicate with a smartphone via a wired (USB port connection) or wireless (Bluetooth, Wi-Fi, etc.) connection with a suitable app installed. The app may upload data from the VSMD to the smartphone and / or further upload it to RPMS for use by the app. The app may also perform, for example, firmware updates to the VSMD, future upgrades, etc.

[0043] The devices, systems, and methods described herein can be embodied in other specific forms without departing from their spirit or essential attributes. Therefore, reference should be made to the appended claims rather than the above description to indicate the scope of the innovation described herein.

Claims

1. An apparatus for measuring blood pressure through the ventral side (the "finger pulp") of a human finger, comprising: a. A flexible and arcuate inflatable blood pressure measuring bladder (the "measuring bladder") that is adapted to contact only the underside of the finger, forms a finger pulp contact surface, and has a surface that applies pressure to the finger pulp when inflated; b. An adjustable force structure (the "force structure") that is separate from the measuring bladder and is adapted to apply force adjustably to a portion of the upper side of the finger opposite the finger pulp to press the finger pulp against the finger pulp contact surface; c. A measuring bladder pump in pneumatic communication with the measuring bladder for inflating the measuring bladder; d. A relief valve in pneumatic communication with the measuring bladder for deflating the measuring bladder; e. A pressure sensor that provides data representing the air pressure within the measuring bladder; f. A control system that receives the data from the pressure sensor and controls the operation of the measuring bladder pump and the relief valve, the control system being configured to: i. Inflate the measuring bladder so that the finger pulp contact surface is pressed against the finger pulp and the upper side of the finger is pressed against the force structure; ii. Stop inflating the measuring bladder when a predetermined inflation pressure (the "inflation pressure"), which is defined to substantially stop the flow of blood in the artery of the finger pulp, is reached, and then controllably deflate the measuring bladder; iii. Monitor the pressure data and detect the resumption of blood flow in the artery by detecting pressure oscillations within the measuring bladder; iv. Detect the time when normal blood flow resumes due to the pressure oscillations and the pressure (the "deflation pressure") at which normal blood flow resumes; v. An apparatus comprising a microprocessor and program instructions stored in memory for calculating a blood pressure indication based on the inflation pressure and the deflation pressure.

2. The apparatus of claim 1, further comprising a substantially rigid arcuate cradle, wherein the measuring bladder is located on the side opposite the finger pulp contact surface and has a lower side fixed to the cradle such that the measuring bladder substantially conforms to the shape of at least a portion of the arc of the cradle.

3. The device according to claim 2, further comprising a slotted structure provided on one side portion of the cradle, wherein the force structure has a hook-and-loop fastening strap fixed to the side portion opposite to the cradle, and the fastening strap is hung so as to wind along a finger placed in the cradle for applying the force to the finger, is folded back after passing through the slotted structure, and is fastened to itself.

4. The device according to claim 3, wherein the force structure further has an arcuate cap flexibly connected to the cradle, and the cap forms a closure covering the cradle to define a cavity that enables the finger to be received between the inner surface of the cap and the finger pad contact surface, and the fastening strap extends on the outermost surface of the cap such that the strap applies the force to the finger via the cap path.

5. The device according to claim 4, wherein the cap is hinged to one side portion of the cradle so that the cap can be rotated to expose the finger pad contact surface and enable the finger to be received.

6. The device according to claim 4, wherein the cap is flexibly connected to opposite side portions of the cradle so as to enable vertical movement of the cap with respect to the measuring bladder.

7. The device according to claim 2, wherein the force structure has one or more shims, the arc of the cradle forms a complete circle to define a cavity, the measuring bladder is provided only in the bottom portion of the cavity, and the upper portion of the cavity is adapted to receive one or more of the shims.

8. The device according to claim 2, wherein the force structure has a bladder ( "boosting bladder") separate and independent from the measuring bladder, the arc of the cradle forms a complete circle to define a cavity, the boosting bladder is provided only in the bottom portion of the cavity, the boosting bladder is provided in the upper portion of the cavity, and inflation of the boosting bladder presses the finger against the finger pad contact surface.

9. The device according to claim 8, further comprising a boosting bladder pump that is separate and independent from the measuring bladder pump and inflates the boosting bladder.

10. The booster bladder pump has a syringe pneumatically coupled to the booster bladder, the apparatus of claim 9.

11. The booster bladder pump consists of a bolus pump integral with the cradle, the apparatus of claim 9.

12. The force structure further has an arcuate cap flexibly coupled to the cradle, the cap forming a closure covering the cradle to define a cavity adapted to allow receipt of the finger between the inner surface of the cap and the finger pad contact surface, the force structure having a strap extending from one side of the cavity over or through the cap to the opposite side of the cavity, and an adjustment mechanism for controlling the tension applied to the cap via the strap so as to apply the force, the apparatus of claim 2.

13. The apparatus of claim 1, wherein no electromagnetic radiation (EMR) sensor is employed to provide an indication of blood pressure and no EMR data is present for calculating an indication of blood pressure.

14. The apparatus of claim 1, wherein the blood pressure indication is calculated based only on the pressure data measured from the pressure sensor.

15. The apparatus of claim 1, further comprising a light emission and light detection system for detecting the amount of light transmitted through or reflected from the index finger portion of the finger, and program instructions for calculating an indication of vital signs based on the detected amount of transmitted and reflected light, with other indications including blood glucose level, respiratory rate, peripheral oxygen saturation, blood volume, total hemoglobin, pulse wave variability index, methemoglobin, acoustic respiratory rate, carboxyhemoglobin, oxygenation reserve index, oxygen content, nitric oxide, microvascular blood flow, EEG hematocrit value, and total protein amount.

16. The apparatus of claim 2, wherein the force structure is adapted to apply sufficient pressure to the upper side of the finger to limit lateral movement of the finger pad to a range of from about 0.4 mm to about 4 mm relative to the finger pad contact surface.

17. An apparatus for measuring a human blood pressure (BP) through the ventral side (the "finger pad") of a finger, a) having a base with a top and a bottom, b) having a substantially inflexible arcuate cradle attached to the top of the base to facilitate receipt of the finger, c) a flexible inflatable blood pressure measurement bladder ("measurement bladder") having a lower side fixed to the cradle, the measurement bladder being adapted to substantially conform to the shape of at least a portion of the arc of the cradle, the upper side of the measurement bladder constituting a finger pad contact surface and being adapted to apply pressure to the finger pad when inflated, d) a separate adjustable force applying structure ("force structure") for applying force adjustably to the upper side of the finger pad to press the finger pad against the finger pad contact surface and sufficient to limit lateral movement of the finger pad within a range of about 0.4 mm to about 4 mm relative to the finger pad contact surface, e) a measurement bladder pump and a measurement bladder relief valve for inflating and deflating each of the measurement bladders, and a pressure sensor for providing data representative of air pressure and air pressure oscillations within the measurement bladder, each of the measurement bladder pump, the measurement bladder relief valve and the pressure sensor being provided within the base, f) no light emitter or detector system is provided for providing an indication of BP, g) a control system provided within the base and coupled to the measurement bladder pump, the measurement bladder relief valve and the pressure sensor, the control system controlling the operation of the measurement bladder pump and the measurement bladder relief valve and processing data received from the pressure sensor to, i. inflate the measurement bladder so that the finger pad contact surface is pressed against the finger pad and the upper side of the finger is pressed against the force structure, ii. stop inflation of the measurement bladder when a predetermined inflation pressure ("inflation pressure") is reached which is determined to substantially stop the flow of blood in the artery of the finger pad, and then controllably deflate the measurement bladder, iii. detect the resumption of blood flow in the artery by monitoring the pressure data and detecting vibrations within the measurement bladder, iv. detect the time when normal blood flow resumes due to the pressure oscillations and the pressure ("deflation pressure") when normal blood flow resumes, v. calculating an indication of blood pressure based on the inflation pressure and the deflation pressure by generating a heart rate power spectrum from a waveform, and then applying a constant rate method to provide indications of systolic BP and diastolic BP, comprising a microprocessor and a memory storing program instructions executable by the microprocessor, An apparatus in which none of the steps g(i) to g(v) employs data from a light emitter or a light detector. **Claim 18** The apparatus according to claim 17, wherein the force structure has a slotted structure provided on one side of the cradle and a hook-and-loop fastening strap fixed to the opposite side of the cradle, the fastening strap being looped along a finger placed in the cradle to apply the force to the finger, folded back through the slotted structure, and fastened to itself. **Claim 19** The apparatus according to claim 17, wherein the force structure further has an arcuate cap flexibly connected to the cradle, the cap forming a closure covering the cradle to define a cavity that allows the finger to be received between the inner surface of the cap and the finger pad contact surface, and the fastening strap extending on the outermost surface of the cap such that the strap applies the force to the finger via the cap path. **Claim 20** The apparatus according to claim 17, wherein the force structure has one or more arcuate shims, the arc of the cradle forms a complete circle to define a cavity, the measurement bladder is provided only within the bottom portion of the cavity, and the upper portion of the cavity is adapted to receive one or more of the shims. **Claim 21** The apparatus according to claim 17, wherein the force structure has a bladder (a "force-applying bladder") separate and independent from the measurement bladder, the arc of the cradle forms a complete circle to define a cavity, the force-applying bladder is provided only within the bottom portion of the cavity, and the force-applying bladder is provided within the upper portion of the cavity such that inflation of the force-applying bladder presses the finger against the finger pad contact surface. **Claim 22** The force structure further has an arcuate cap flexibly connected to the cradle, the cap forming a closure covering the cradle so as to define a cavity adapted to allow the finger to be received between the inner surface of the cap and the finger pad contact surface, the force structure being provided with a strap extending from one side of the cavity onto or through the cap to the opposite side of the cavity, and an adjustment mechanism for controlling the tension applied to the cap via the strap so as to apply the force. The device according to claim 17.

23. The device further comprises a light emission and light detection system (PLMS) for detecting the amount of light transmitted through or reflected from the index finger portion of the finger, and program instructions for calculating the indication of vital signs based on the detected amount of transmitted and reflected light. Other indications include blood glucose level, respiratory rate, peripheral oxygen saturation, blood volume, total hemoglobin, pulse wave variability index, methemoglobin, acoustic respiratory rate, carboxyhemoglobin, oxygenation reserve index, oxygen content, nitric oxide, microvascular blood flow, EEG hematocrit value, and total protein amount. The PLMS has a housing for receiving the finger placed on the top of the base in a substantially axially aligned state with the cradle, and the BP measurement value is taken at the distal end of the finger. The cradle, the PLMS, the measurement bladder pump, the measurement bladder relief valve, the force structure and the control system are a single integrated and self - contained stand - alone unit. The device according to claim 16.

24. A method of using the device, wherein the device a. has a substantially inflexible arcuate cradle, b. has a flexible and arcuate inflatable blood pressure measurement bladder (the "measurement bladder") provided with a lower side fixed to the cradle, the measurement bladder being substantially conformable to the shape of at least a portion of the arc of the cradle, the upper side of the measurement bladder constituting a finger pad contact surface and being adapted to apply pressure to the human finger pad when inflated, c. a measurement bladder pump in pneumatic communication with the measurement bladder for inflating the measurement bladder d. a relief valve in pneumatic communication with the measurement bladder for deflating the measurement bladder; e. a pressure sensor for providing data representative of the air pressure within the measurement bladder; f. a control system for receiving the data from the pressure sensor and controlling the operation of the measurement bladder pump and the relief valve, the control system: i. inflates the measurement bladder such that the finger pad contact surface is pressed against the finger pad and the upper side of the finger is pressed against the force structure; ii. stops inflation of the measurement bladder when a predetermined inflation pressure ("inflation pressure") is reached which is defined to substantially stop the flow of blood in the artery of the finger pad, and then controllably deflates the measurement bladder; iii. monitors the pressure data and detects the resumption of blood flow in the artery by detecting vibrations within the measurement bladder; iv. detects the time when normal blood flow resumes due to the pressure oscillations and the pressure ("deflation pressure") when normal blood flow resumes; v. includes program instructions stored in a microprocessor and memory for calculating a blood pressure indication based on the inflation pressure and the deflation pressure; The method comprises: g. inserting a finger into the cradle such that the finger pad contacts the finger pad contact surface; h. applying a force to a portion of the finger located on the side opposite the finger pad that is less than or equal to the magnitude required to prevent the finger from moving laterally relative to the finger pad contact surface by more than about 0.4 mm and less than about 4 mm; i. causing the control system to initiate the operations of steps f(i) to f(v).

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