Patent Application
20210153762
The contents of the following are incorporated herein by reference pursuant to 37 CFR § 1.57(d):
The subject matter described herein relates to a wearable suite of components for monitoring a subject, such as a medical patient, and to a method of preparing the patient for monitoring by the suite of components.
It is often desirable to monitor selected parameters of a person, referred to herein as a subject or patient. Parameters of interest include vital signs such as respiration rate, and cardiac signals including signals necessary to establish the patient's heart rate. The parameters of interest may also include parameters not traditionally thought of as vital signs such as the patient's position (particularly his position in or relative to a bed) and patient movements including velocity and acceleration. In this specification, references to vital signs or other patient related parameters may refer to the vital sign itself or may refer to the signals detected by sensors, typically electrical signals, processing of which leads to an estimate of the parameter of interest. For example respiration rate may mean the number of breaths per unit time or may mean the sensed signals which can be processed to estimate the number of breaths per unit time. The meaning will be clear from context and/or the distinction between an actual parameter and the signals used to determine its value are interchangable in connection with understanding the following description and the metes and bounds of the accompanying claims.
Parameter monitoring as described above is often carried out in health care settings such as hospitals. Monitoring may also be carried out while the patient goes about his day to day activities. Wearable monitors, which contain the sensors and other components required for the monitoring task, are attractive for such purposes. A wearable monitor is one that is maintained in a fixed position on the patient, for example by being adhered to his skin. “Position” refers to the location of the sensor relative to anatomical features of the patient and may also include the locations or orientations of the sensors relative to each other. “Fixed” means that the position of each sensor remains sufficiently unchanged that its readings remain valid and useful during the time interval that the monitor is in use. In a health care facility a compact, wearable monitor may satisfy monitoring requirements that would otherwise call for the use of multiple pieces of expensive, bulky equipment. In the day to day setting a compact, wearable monitor offers the patient considerable freedom to go about his normal daily activities.
Wearable monitors present a number of design challenges. First, certain of the monitor's sensors must be accurately positioned on the patient in order to achieve the best possible readings. If the patient is to be monitored for a period of, say, several days, it is desirable to leave those sensors in place for the entire duration of the monitoring period. This is because if the sensors are removed and subsequently reapplied to the patient, a caregiver will have to devote time and effort to re-establish accurate positions for the sensors. Even if the caregiver is able to do so, the subsequent location may differ somewhat from the previous location, compromising the repeatability of measuring the signals of interest. In addition, the means used to hold the sensor onto the patient should be breathable in order to allow for air circulation to the patient's skin. In addition, the monitor should be comfortable to wear and durable.
Another design challenge is that some of the monitor's sensors, and/or the electrical components associated with them, might not be tolerant of degrading influences such as radiation exposure during a radiological procedure. Therefore, notwithstanding the desirability of leaving sensors in place for the entire duration of the monitoring period, there may be a need to remove certain sensors from the patient while the degrading influence is present and reapply them to the patient after the degrading influence is no longer present. As noted above it is desirable to re-apply the removed sensors in essentially the same position they occupied relative to the patient's anatomical features prior to removal.
Accordingly, what is needed is a means to effect the attachment of a wearable monitor to a patient which has the attributes of breathability, durability, and comfort. What is additionally needed is an attachment means which is resistant to influences that tend to separate the attachment means from the patient and which is resistant to degrading influences. To the extent that the monitor includes sensors that are not resistant to degrading influences, what is needed is a monitor whose architecture enables those sensors to be temporarily and conveniently removed, and to be conveniently put back in place after the degrading influence is no longer present.
In view of the foregoing this specification describes a suite of components for monitoring a subject. The suite of components may also be considered to be a kit of components. The suite of components may also be considered to be a system of components, at least when the components are assembled to each other in order to monitor the patient. The component suite includes one or more ECG electrodes, a securement component adapted to hold the one or more electrodes to the subject's body, and a host removably connected to or adapted to be removably connected to the one or more electrodes. The host includes a sensor, a processor and an energy source.
This specification also describes a method of preparing a subject for monitoring with a suite of components which includes 1) one or more electrodes each having a contact portion with an adhesive surface and a snap assembly projecting away from an opposite or top surface of the contact portion, 2) a securement component having an adhesive side and one or more holes with each hole corresponding to a pre-established electrode pattern, and 3) a host adapted to receive and remain removably attached to the electrodes. The method itself includes the steps of A) installing the electrodes in the module thereby forming an electrode/module subassembly, B) placing the subassembly at a monitoring site on the subject whereby the adhesiveness of the adhesive surface of the electrodes causes the electrodes to adhere to the subject, C) disconnecting the module from the adhered electrodes, D) adhering the securement component to the subject so that each snap assembly projects through one of the holes in the securement component, and E) reconnecting the module to the adhered electrodes.
The foregoing and other features of the various embodiments of the component suite and method will become more apparent from the following detailed description and the accompanying drawings in which:
The present invention may comprise one or more of the features recited in the appended claims and/or one or more of the following features or combinations thereof.
In this specification and drawings, features similar to or the same as features already described may be identified by reference characters or numerals which are the same as or similar to those previously used. Similar elements may be identified by a common reference character or numeral, with suffixes being used to refer to specific occurrences of the element.
Referring to
Each electrode 50 includes a patch of comfort gel 54 and a ring of hydrocolloid adhesive 56 whose outer and inner diameters both exceed the diameter of gel patch 54. As a result, dismounting of the electrode from the release liner exposes an annular adhesive surface. Adhesive 56 adheres the electrode to the patient's skin however, as described below, is not the exclusive means for maintaining the electrode at a fixed position on the patient. The comfort gel makes the electrode more comfortable to the patient.
Each electrode also includes a lower pressure sensitive adhesive layer 62, a polyethelene layer 64, an upper foam pressure sensitive adhesive layer 66, and a foam layer 68. Taken collectively, components 54, 56, 62, 64, 66, 68, are referred to as the contact portion 72 of the electrode. Each electrode also includes a snap assembly 74 comprising an electrode magnetic snap 76 and an electrode eyelet 78. When the electrode is in its assembled state, eyelet 78 nests inside magnetic snap 76, and the snap assembly projects above electrode contact portion 72. Despite the nomenclature, magnetic snap 76 of the illustrated embodiment is ferrous, but is not magnetic. As explained in more detail below, the snap assembly and a host component of the component suite are removably connected to each other. However despite the nomenclature “snap”, the connection is a magnetic connection, not a mechanical snap connection.
The adhesive 104 employed on the bottom of the securement component is one that adheres strongly enough to the patient's skin to resist detachment for a specified period of time, for example approximately seven days, and weakly enough to be intentionally removed from the patient's skin without damaging the patient's skin. One benchmark for skin damage is breaking the skin.
One material which may be useful for the securement component is Tegader™ transparent film dressing, a 3M™ product. Tegaderm is said to provide a waterproof, sterile barrier to external contaminants, has an adhesive which is gentle to the skin, and flexes with the skin to enhance patient comfort.
The illustrated host 130 includes a first module 132 which is referred to herein as a power module 132. The power module includes a first housing 136 comprised of a first housing base 138 and a first housing cover 140. The first base and the first cover define an interior 142 of the first housing. Housing base 138 has two coupler openings, 146. The housing cover includes a perimeter flange 152 and an archway 154. A housing adhesive, not shown, on at least the top of the perimeter flange is provided to connect the cover to the base.
The power module also includes a chassis adhesive 156 and a chassis 158. The chassis includes internally threaded posts 166 at each corner thereof, a central opening 168, and an archway seat 170 shaped similarly to archway 154 except for a longitudinally projecting tube segment 172. The bottom of the chassis also includes recesses 174.
The power module also includes a Qi charging receiver 180, a Qi receiver adhesive 182 which holds charging receiver 180 to chassis 158, a battery 184, and a foam battery spacer 186 between the battery and the Qi receiver. The battery is the energy source for the host. Qi charging works by transferring energy from a nearby charger, which is external to the host, to the receiver by way of electromagnetic induction. The charger uses an induction coil to create an alternating electromagnetic field, which the receiver converts back into electricity to be fed into the battery. Wireless charging arrangements other than Qi charging may be used. Wired charging arrangements may also be used.
The power module also includes a battery cover 190. Screws 192 threaded into posts 166 secure the battery cover to the chassis so that battery 184, spacer 186, Qi receiver 180, and Qi receiver adhesive 182 are contained with a space defined by the battery cover and chassis. When cover 140 and base 138 are sealed to each other at cover flange 152, the battery cover 190, battery 184, spacer 186, Qi receiver 180, Qi receiver adhesive 182, chassis 158 and chassis adhesive 156 are all contained in the interior space defined by the base and cover. A band of adhesive 194 between archway 154 and archway seat 170, in combination with the housing adhesive along perimeter flange 152, helps seal against ingress of water and other contaminants into the housing interior.
Magnetic electrode couplers 210S−, 210D− reside in chassis recesses 174. “Magnetic”, as used in the phrase “magnetic electrode coupler” indicates that the coupler is magnetic. This is in contrast to magnetic snaps 76 of electrodes 50 which, as previously noted, are ferrous but not magnetic. The locations of the couplers are referred to as connection sites and are identified with reference numeral 212. As described in more detail below, when the component suite is being employed to monitor the patient, magnetic attraction between the magnetic couplers 210S−, 210D− and snaps 76 of electrode snap assembly 74 cause power module 132 to be removably engaged with the ECG electrodes. The couplers also serve as impedance plethysmography (IPG) negative drive and sense electrodes, hence the D− and S− suffixes. The unsuffixed reference numeral 210 may be used herein when the text is referring to the coupling function of the couplers but not to their plethysmography function.
The illustrated host also includes a second module 232 which is referred to herein as a processor module 232. Features of the processor module which are the same as or analogous to features of the power module are or may be identified with the reference numerals of the power module incremented by 100. The processor module chassis adhesive 256, chassis 258, magnetic couplers 310S+, 310D+ (analogous to couplers 210S−, 210D− of power module 132), and adhesive band 294 are the same as their counterpart elements of the power module. (Unsuffixed reference numeral 310 may be used herein when the text is referring to the coupling function of the couplers but not to their plethysmography function.) The processor module housing cover 240 is the same as the power module housing cover 140 except that the processor module has a heart shaped emblem 320, and the power module is either plain as in
The processor module also includes a temperature sensing assembly 330 comprised of a sensor housing 332, a temperature sensor 334 and temperature sensor circuitry 336. The illustrated temperature sensor is an infrared sensor, i.e. it is responsive to infrared wavelengths. The illustrated sensor circuitry is a printed circuit assembly (PCA). As seen best in
The processor module also includes a foam spacer layer 340 with a center hole 342, and a main circuit board or main PCA 346. Wires, not shown, pass through center hole 342. A foam plug 344 also occupies the hole. Together, foam layer 340 and plug 344 provide thermal and electrical insulation between main PCA 346 and temperature sensor 334.
Referring additionally to
Processor module 232 also includes a PCA cover 360 with a heart shaped opening 362. When the module is assembled as seen in
In summary, the processor module includes at least one sensor. These may include IPG sensors for estimating the patient's respiratory rate, temperature sensor 334 for estimating the patient's skin temperature, and an acceleration sensor 352. Readings from the accelerometer may be used to monitor for accelerations that might indicate a health related problem (e.g. tremors, shivering, coughing) or might indicate that the patient in moving in an undesirable way (e.g. attempting to make an unauthorized exit from his bed). The accelerometer readings may also be integrated or double integrated over time to establish an estimate of the speed of patient movement and the patient's present position.
Host 130 also includes a conduit 370. Each end of the conduit circumscribes one of the tube segments 172, 272 that extend from the chassis of the power and processor modules. An adhesive, not shown is applied to the outside surface of the tube segments to help secure the connection. The tubes may also be barbed to resist separation of the conduit. The conduit has a length such that when the ECG electrodes are correctly positioned on the patient and engaged with modules 132, 232, the conduit will accommodate a patient size range from a 5th percentile female to a 95th percentile male. Wiring, not shown, extends through the conduit. The wiring includes two wires from the battery, two wires connecting the Qi charger to the Qi charger circuitry, one wire from the IPG sense electrode and one wire from the IPG drive electrode.
Host 130, represented in
Continuing to refer to
The magnetic attraction between electrode snaps 76 and housing magnetic couplers 210, 310 is strong enough to hold the module and its sensors in a fixed position relative to the ECG electrodes, and therefore in a fixed position relative to the patient's anatomical features. The magnetic attraction is strong enough to achieve this state of securement even if the module is bumped or otherwise exposed to actions or conditions that might dislodge it from the electrodes. However the magnetic attraction is weak enough that if the module needs to temporarily removed, such removal can be easily accomplished without special tools and with a force well within the capabilities of a human caregiver. As already explained such temporary removal might be required to avoid subjecting the module, or the components contained within it, to a degrading influence such as radiation. Moreover, the required separation force is also small enough that its application will break the magnetic bond at the snap/coupler interface rather than separating the securement component from the patient's skin.
In view of the foregoing, certain variations and generalizations can now be better appreciated.
In general, the host can be a single module or can be comprised of three or more modules, rather than the two modules described so far. Each module may include fewer or more than the two connection sites described above. Moreover the quantity of connection sites need not be the same on all the modules. If the quantity of connection sites is the same on two or more modules, is it not necessary for the spatial distribution pattern of those connection sites to be the same.
In a more specific example in which the host is comprised of exactly two modules, a first of the two modules is adapted to be removably connected to M ECG electrodes. The first module includes exactly N electrode connection sites, one for each of the N ECG electrodes. The N electrode connection sites are spatially distributed in a first connection site pattern. “Connection site pattern” means the spatial relationships amongst the N connection sites, A second module is adapted to be removably connected to N ECG electrodes. The second module includes exactly N electrode connection sites, one for each of the N ECG electrodes. The N electrode connection sites are spatially distributed in a second connection site pattern. The set of electrodes includes exactly N+N electrodes. In one specific embodiment N=N.
Referring to
The set of N electrodes may be packaged similarly to the way just described in connection with the set of N electrodes so that they are spatially distributed in a second electrode pattern which matches the second connection site pattern. The above example of the N electrode arrangement suffices for the reader to understand the N electrode arrangement. The first and second connection site patterns may be replicas of each other or may differ from each other. N may be equal to N or N may differ from N. In one embodiment N=N=2.
As seen in
The method includes the step, at block 400, of installing the electrodes 50 in the module 132 thereby forming an electrode/module subassembly 394.
The method also includes the step, at block 408, of placing subassembly 394 at a monitoring site on a patient. The adhesiveness of the adhesive surface causes the electrodes to adhere to the patient, e.g. to his skin.
The method also includes the step, at block 410, of disconnecting the module from the adhered electrodes. In other words a caregiver lifts up the module, breaking the magnetic connection between the snap assemblies of the electrodes and the magnetic coupler of the host. The adhesiveness of the adhesive surface causes the electrodes to remain adhered to the patient.
The method also includes the step, at block 412, of adhering the securement component to the patient so that each snap assembly 74 projects through one of holes 96 in the securement component.
The method also includes the step, at block 414, of reconnecting the module to the adhered electrodes. In other words the caregiver places the module over the electrodes so that the magnetic connection between each electrode and its companion magnetic coupler is re-established.
At the conclusion of reconnecting step 414 the monitor is secured to the patient, with the module removably secured to the electrodes. Securement of the electrodes to the patient is enhanced by the presence of securement layer 90. The caregiver may then press the ON/OFF switch on the module to commence patient monitoring.
The method shown in
As noted in the Background section of this application, certain of the monitor's sensors must be accurately positioned on the patient in order to achieve the best possible readings. In other words the caregiver needs to identify a location on the patient's body that will be clinically satisfactory for the monitor. To do so the caregiver can position the monitor on or near the patient's body with patient side release liner 100 still covering the adhesive layer 56 of the electrodes. However when the caregiver lifts the monitor away from the patient in order to peel off the protective liner, he may lose track of the identified satisfactory location.
Therefore, the monitor may include one or more features to address the above described difficulty. Examples of such features are the progressive release feature illustrated in FIGS. 25-26 of U.S. patent application Ser. No. 16/150,572, and registration notches illustrated in FIGS. 27-28 of that application.
In the foregoing description, securement component 90 is described as a component separate from the host component 130 (power module 132 and processor module 232) and from EKG electrodes 50. In another embodiment the securement component is part of an assembly that includes an electrode or a set of electrodes.
Although this disclosure refers to specific embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the subject matter set forth in the accompanying claims.
| Number | Date | Country | |
|---|---|---|---|
| 62818271 | Mar 2019 | US |
