FIELD

The present invention is generally directed towards providing a low cost and easy to use device to measure essential health parameters and detect abnormal health conditions and in particular, towards a method and device for detecting hypothermia

BACKGROUND

Hypothermia and infection are among top health issues facing several patients including Indian newborns. Regular temperature monitoring is an effective means of prevention but it is very difficult to regularly practice in under-resourced clinics and uneducated homes

As an example, an estimated 4-12 million of India's newborns experience hypothermia yearly, often resulting in poor organ development, life-debilitating illness and death. Also, every year bacterial infections (sepsis) cause approximately 250,000 infant deaths in addition to millions of life-impacting illnesses. Hypothermia and infection are also among the top pain-points and the standard of care technologies and practices are presently inadequate.

Hypothermia and infection are especially significant neonatal concerns in India. 1 in 3 of India's infants is born under 2.5 kgs compared to rates of almost 1 in 12 in the developed world. These low birth weight infants are at much higher risk for hypothermia and sepsis. Whereas in developed countries, these babies are almost never discharged from hospitals until they reach a weight of 2.2kgs, it is not uncommon to see 1.4kg babies discharged in Indian clinics, assuming that the babies were born in a clinic in the first place. Furthermore, the majority of India's babies are born in government centers or homes often lacking adequate staff, equipment and central heating. And, with India's 65% female literacy rate, a large proportion of mothers are not educated impacting their ability to manage their newborn's health.

The WHO promotes the concept of "warm-chain management," a series of 10 interconnected steps, such as a warmed delivery room, delayed bathing, skin-to-skin warming, to prevent any opportunity for an infant to become cold. However, many aspects of "warm chain management" are impractical. Furthermore, there is almost no awareness of warm chain management in most Indian homes.

Regular temperature monitoring has the ability to prevent hypothermia and to catch infections, which often present as fever or hypothermia in newborns. In fact, regular temperature monitoring is the standard of care in developed countries. However,

1. In Indian clinics, there are few nurses and they often skip temperature readings in light of competing priorities.

2. In Indian homes, mothers cannot operate and interpret thermometers due to lack of awareness and education.

Current practices for temperature monitoring and maintenance are inadequate. As a "jugaad" solution for temperature monitoring, a person's body is felt to determine temperature and mothers are taught to feel their baby's arms for coldness and take action if necessary. But, using these techniques and even while practicing this method regularly, they still miss 25% of hypothermia cases. Similarly, mothers are often instructed to practice kangaroo mother care as a means to prevent an infant from becoming cold, but compliance, especially at home, is low.

SUMMARY

It is an objective of the present invention to provide a device for monitoring and detecting hypothermia, comprising of one or more temperature sensors configured to sense and measure body temperature and one or more physiological phenomena as parameters continuously or at regular intervals, one or more control units operatively connected to the one or more sensors and configured to determine if one or more parameters is outside an acceptable range and accordingly signal the alerting unit , and an alerting unit operatively connected to the one or more control units and comprising of one or more alarms configured to provide one or more alerts based on the signals received from the control unit.

It is another objective of the present invention to provide a method for monitoring and detecting hypothermia, comprising the steps of measuring the body temperature and one or more physiological phenomena as parameters continuously or at regular intervals; determining hypothermia based on the difference of the measured temperature and the ambient temperature and previous temperature measurements; and activating one or more alarms if hypothermia is detected

The key physiological phenomenon considered is that of peripheral temperature decrease (caused by peripheral vasoconstriction of blood vessels) of the human body prior to the subsequent decrease in temperature of the core body. Detection of this phenomenon can lead to early detection of hypothermia and enable intervention.

The primary goal of the invention is to be able to use this device to drastically reduce rates of death and illness due to detectable diseases such as hypothermia and sepsis. In a preferred embodiment, the device is a simple and low-cost wearable device capable of monitoring and detecting abnormalities in health parameters, such as temperature and heart rate, and intuitively providing an alert in case of abnormalities such as hypothermia or infection.

In a preferred embodiment, the device is a wearable monitoring wristband that continuously monitors a patient's health parameters. For example, if the infant becomes cold, intuitive and well- designed alarms alert a mother to warm her infant before the baby can become hypothermic. Repeated and more severe alarms signal that the infant is unable to stay warm implying that an underlying infection may be present. The more severe alarms alert the mother early to get skilled intervention before the infection worsens. These alarms can be set or programmed to be periodic and repetitive at desired time intervals and may be in the form of sound alarms or colour or light alarms. The type and duration of the alarm may signify the severity of the symptom or provide an indication of the problem

The device of the present invention is more accurate than touch-monitoring. Hand-touch monitoring, while low-cost and culturally acceptable, is shown to have low accuracy in detecting hypothermia. Furthermore, it is not de facto taught to everyone especially in settings with low staff. Furthermore, the practice is not complied to nor regularly practiced even when training is given.

The device of the present invention is cheaper than vital monitoring systems. These high end systems monitor multiple vital parameters and currently only exist for hospital use or use by skilled staff.

BRIEF DESCRIPTION OF DRAWINGS

The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the drawings to reference like features and components.

• FIGURE 1 shows a low-weight infant being exposed to cold temporarily

• FIGURES 2A and 2B show block diagrams of a preferred embodiment of the device, defining the main components used, for example a temperature sensor, buzzer and microcontroller.

• FIGURE 3 depicts a flow-chart of the control method and how the device functions and can be used

• FIGURES 4A and 4B depict a preferred band embodiment of innovation with a skin sensor • FIGU RE 5 depicts an embodiment of the invention with an intuitive alert for hypothermia.

DETAILED DESCRIPTION OF THE DRAWINGS

Exemplary embodiments now will be described with reference to the accompanying drawings. The disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey its scope to those skilled in the art. The terminology used in the detailed description of the particular exemplary embodiments illustrated in the accompanying drawings is not intended to be limiting. In the drawings, like numbers refer to like elements.

The specification may refer to "an", "one" or "some" embodiment(s) in several locations. This does not necessarily imply that each such reference is to the same embodiment(s), or that the feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments.

As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless expressly stated otherwise. It will be further understood that the terms "includes", "comprises", "including" and/or "comprising" when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may be present. Furthermore, "connected" or "coupled" as used herein may include wirelessly connected or coupled. As used herein, the term "and/or" includes any and all combinations and arrangements of one or more of the associated listed items. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The figures depict a simplified structure only showing some elements and functional entities, all being logical units whose implementation may differ from what is shown. The connections shown are logical connections; the actual physical connections may be different. It is apparent to a person skilled in the art that the structure may also comprise other functions and structures.

In addition, all logical units described and depicted in the figures include the software and/or hardware components required for the unit to function. Further, each unit may comprise within itself one or more components, which are implicitly understood. These components may be operatively coupled to each other and be configured to communicate with each other to perform the function of the said unit.

The device is designed to improve health outcomes specifically in the Indian context. In preferred embodiments, key features of the device include:

• Intuitive and useable by uneducated persons; does not require skilled staff nor training time from hospital staff

• Useable in a home setting, in addition to a clinic

• Does not require a power supply

• Designed to look culturally acceptable and appealing

• Fits small (low birth weight or premature) babies as well as large patients

• Promotes Kangaroo Mother Care, a proven health intervention for low-resource settings In a preferred embodiment, the device is a simplified thermometer. A vast majority of people in India and other developing countries have never used a thermometer. Similarly, although doctors and nurses have tried training uneducated mothers to use thermometers, they cannot trust such a newly trained mother to now be able to maintain normo-thermia or detect infections in her newborn. In such situations, the device adds continuous monitoring, which is especially useful at night-time.

FIGURE 1 explains the physiological phenomenon of cold peripheries caused by vasoconstriction of peripheral vessels which enables the device to detect hypothermia earlier than other temperature monitoring devices. The figure shows a low-weight infant being exposed to a cold environment temporarily. This is illustrated by the bar at Time =14. The baby's core temperature (Tc) drops almost to hypothermia when the cold exposure is stopped. Accordingly there is a large drop in peripheral limb temperature (Tp) first which the device will alarm. This figure depicts the phenomenon of peripheral skin temperature, for example at the wrist, dropping significantly colder and earlier than the core (for example abdomen) temperature for a human. This is caused due to peripheral vasoconstriction of blood vessels at the peripheries causing warm blood to be conserved for the core organs and not the peripheries. Note that hypothermia is typically defined when the core body temperature goes below 36.5 C, however the peripheries will be colder than this due to the physiological phenomenon described. Since the present invention can monitor at the peripheries, this phenomenon can be detected early allowing intervention before core temperature decreases causing organ injury and other consequences.

FIGURES 2A and 2B show block diagrams of a preferred embodiment of the device. The device can be described as containing multiple subsystems contained in a physical embodiment. Figure 2A shows a simplified view of the subsystems. One or more sensors (101) are configured to sense and measure body temperature and one or more physiological phenomena as parameters at continuous or regular intervals. The one or more control units (102) use a technique as described later in Figure 3 to determine whether to signal the alerting unit (103). The control unit (102) has the ability to trigger another measurement if required to make a further evaluation of the health state. Figure 2B shows a basic example layout of the major components of the innovation. The temperature sensor (101) provides information to the control unit (102) which makes the decision to signal the alerting unit (103) a. The sensors (101) make contact with the skin of the patient. They measure the skin temperature and transfer this measurement to the control unit (102) at continuous, regular or scheduled intervals. In the preferred embodiment, this unit has a thermistor temperature sensor which is placed inside a steel cup. The cup is filled with conductive glue to hold the thermistor in place and to facilitate faster skin temperature measurement. The cup is placed at the bottom of the band and makes flush contact with the skin. A separate temperature sensor sits inside the body of the casing or just outside the casing and measures the "ambient" temperature. The ambient temperature and skin temperature may be compared by the control unit to determine if the device is on or off the wearer. This sensor can also be used to better interpret whether the patient has been exposed to a cold ambient temperature warranting an alert.

b. The control unit (102) commands the sensors (101) to take a temperature measurement. It then receives the temperature measurement value and applies a technique that is specifically designed to be sensitive and specific for hypothermia in the target population. The technique is designed specifically to rely on the physiological phenomenon of peripheries becoming cold as an early sign of hypothermia. Based on the result of the technique the control unit (102) then commands the alerting unit (103) to give the appropriate alert to the user. If the device alerts the user to take action (such as warm the baby), the device monitors for the result of the action (a warmer temperature) or else sounds a subsequent alarm. This subsystem consists of a PCB with a microchip and several ports. The ports are connected to the 2 thermistors, a buzzer and an LED.

c. The alerting unit (103) interfaces and communicates with the user. Upon receiving a command from the control unit (102), the alerting unit (103) may turn of or on a light, or sound a sequence of tones or audio recordings to inform the user that the patient is normotheric or hypothermic. In a preferred embodiment this unit consists of a single multi-color LED and a magnetic buzzer. There are different alert states for the patient being normothermic, the patient being hypothermic, the patient being still hypothermic, and for the band being removed from the wrist.

In a preferred embodiment, the device may also comprise of a storage unit for storing data regarding one or more alerts provided by the alerting unit i.e. previous detections of hypothermia, data about the device wearer, predetermined acceptable ranges and thresholds etc. In another preferred embodiment, the device may also comprise of a display unit for displaying the stored data or measured values of one or more parameters

The device may have all the units located within the same small casing to enable portability. The device may be embodied as a bracelet, anklet, shoe, armband, thigh band or a mitten.

Physiologically, if an infant is becoming hypothermic, the body first conserves heat by restricting blood flow (vasoconstriction of vessels) to the arms and legs. This causes the limbs to become significantly colder as an early sign of hypothermia. Based on this, in a preferred embodiment, the device of the present invention uses a technique based on a temperature threshold and drop in temperature rate at the wrist to sound an early the alarm to take action.

FIGURE 3 depicts a flow-chart of the control method and how the device functions and can be used. The technique begins by measuring the skin temperature (at a peripheral location) and an ambient temperature location (201). The technique is defined by two decision stages: first to determine if the band is being worn and another to determine if the baby is hypothermic. To determine if the band is worn, the algorithm compares the skin temperature and the ambient room temperature. If the difference is significant, the device can expect the device is being worn (202A) and the technique can move to the second stage of looking for hypothermia. However, if the difference is not significant, the device may not be worn on the patient (202B) and the algorithm will wait for another measurement after some time.

In the second stage of the technique, the skin temperature measurement is used to determine if the baby is at risk for hypothermia (203A, 203B). The technique will consider several previous temperature measurements and calculate a parameter, in the form of the mean, median, min or max of the measurements (204) and compare to a predetermined threshold. Should the threshold be exceeded, this would imply that the baby is hypothermic (205A). In a preferred embodiment, core hypothermia is detected when the core temperature (rectal, intra-esophogeal or similar) is below 36.5. However, the threshold for hypothermia as measured by the device will be different since a peripheral skin temperature is being interpreted. Also, the threshold may be raised or lowered depending on the age of the patient or the sensitivity required. If the technique determines the patient is hypothermic, the device activates an alarm sequence (206) and then waits for a predetermined time (207) to measure temperature again (208). The time before measurement again may be shorter if hypothermia is present. If the patient is not hypothermic (205B), no alarm or a normothermic indication is triggered and the device waits for another period of time before repeating the evaluation again.

FIGURES 4A and 4B depict a preferred band embodiment with a skin sensor. They depict a preferred embodiment of the device as a wristband as shown. In the left image, the front face of the embodiment is shown. A single light is visible in the centre of the device which has the ability to change colours and blink indicating normal or abnormal temperature for the wearer. The device also contains a buzzer or speaker inside the casing which gives an audio alert if needed. The control unit is contained within the body of the device. The right image shows the skin-facing side of the device. A sensor assembly is located on this surface as shown by the metal cup which comes in contact with the skin to measure temperature. The metal cup contains a temperature sensor which conveys the measurement to the control unit contained in the body of the device.

FIGURE 5 depicts an embodiment of the invention with an intuitive alert for hypothermia. A preferred embodiment of the device is a wrist band with a simple and intuitive interface for a parent to understand the health status of their infant. As described in the left image, the device may blink an indication at regular intervals (in this case a blue light every 30 seconds) to indicate that the infant's temperature is normal. As described in the right picture, the device could have a different sound and visual alarm (in this case an orange blinking light with sound) indicating that the baby is hypothermic.

It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. Instructions may also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function/act specified in the flowchart and/or block diagram block or blocks.

Instructions may also be loaded onto a computer or other programmable data processing apparatus like a scanner/check scanner to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

The flowchart and schematic diagrams of Figures 1 to 3 illustrate the architecture, functionality, and operations of some embodiments of methods, systems, and computer program products for time related interaction of a user with a handheld device. In this regard, each block may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that in other implementations, the function(s) noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending on the functionality involved.

In the drawings and specification, there have been disclosed exemplary embodiments of the invention. Although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined by the following claims.