Description:Field of Invention
This invention is related to the contactless monitoring and alerting systems for sick persons. In the recent times, the primary cause of increased mortality rate is because of the lack of oxygen availability to the respiratory system, as with COVID-19. Many people are also suffering from lungs and airway disorders. The patients with these diseases require continuous monitoring of oxygen saturation level, which is a tedious task in hospitals with many patients. This enables the need for a centralized contactless continuous monitoring system.
The objectives of this invention
The aim of this invention is to develop a contactless Oxialert device which detects the oxygen levels and informs the care taking person if the levels are at critical values through a message and phone call. This helps the person (caretaker) to know the health position of a person without being in direct contact. Therefor to invent a non-contact monitoring and alerting device, that is what we all need, especially during the pandemic situation.
Background of the invention
Measuring and monitoring the oxygen level in a patient's blood is an important parameter, as if the oxygen saturation level is low, then an immediate action is needed. Hence, a non-invasive device for detecting the oxygen contents in blood can be very useful. The authors in (P. Jalan, B. R. Bracio, P. J. Rider and H. Toniolo, [2006], Rapid Prototyping of Pulse Oximeter. International Conference of the IEEE Engineering in Medicine and Biology Society, pp. 5579-5582.), have investigated to find-out the suitable hardware and software components for developing an effective pulse oxygen meter. They performed simulated experiments for both hardware and software components to generate results. In (G. Pang and C. Ma, [2014], A Neo-Reflective Wrist Pulse Oximeter. IEEE Access, 2, pp. 1562-1567.), a wrist wearable pulse oxygen measuring device is developed, which can replace the traditional finger pulse oximeters. In another useful contribution in (S. H. Liu, H. C. Liu, W. Chen and T. H. Tan, [2020], Evaluating Quality of Photoplethymographic Signal on Wearable Forehead Pulse Oximeter With Supervised Classification Approaches. IEEE Access, 8, pp. 185121-185135.), a wearable forehead pulse oximeter is developed, which uses support vector machine and convolution neural network techniques for getting accurate readings.
Description of Prior Art
The past decade has witnessed the development of various devices to measure oxygen saturation ratio (SpO2). With the availability of advanced technologies, the current scenario is to manufacture devices which are more accurate, low cost and easy to use. A wireless, disposable method and apparatus is developed in (US11109783B2), for pulse oximeter sensor technology. A method for reducing consumption of power in a pulse oximeter device and its sensors is invented in (US8571622B2). A body-worn device is invented to measure the oxygen saturation levels, the information can be transmitted to the remote receiver for further processing (US11134857B2). The invention presented in (JP2018538038A), talks about the effects of different environmental conditions and parameters which can affect the readings of pulse oximeter.

Summary of the invention
The invented oxialert device can be very effective in continuous monitoring of blood oxygen saturation and providing needed actions when the critical situation arises. This system enables to evaluate the performance of the doctors in the hospital and also the patients can be treated or monitored remotely and that too in contactless mode.
Detailed description of the invention
The main motive behind the patient monitoring system is to diagnose the health condition of the patients effectively. Providing care and health assistance to the bed ridden patients at critical stages with advanced medical equipments and facilities have become one of the major problem of health sector in the modern world. In hospitals where a large number of patients whose physical conditions have to be monitored frequently as a part of continuous diagnostic procedures, the need for a cost effective and fast responding alert mechanism is in extream demand. Proper implementation of such alerting systems can provide timely warnings to the medical staffs and doctors regarding critical situations. The present-day systems have started to install and use various sensor networks that are hardwired to a PC next to the bed. The use of these sensors is to moniter the conditions of the patient and the generated data is collected and transferred using a dedicated microcontroller unit. Doctors and nurses need to visit the patient frequently to examine his/her current condition. In addition to this, use of multiple microcontroller based intelligent system provide high level applicability in hospitals where a large number of patients have to be frequently monitored.
The invented device will operate in the following manner:
When power supply is switched on the MAX 30100 (oxygen sensor) initializes . The sensor has two light emitting diodes, one emits red light with the wavelength of 650nm and other emits near infrared radiation with a wavelength of 950nm . When the patient puts the sensor on his fingre, both infrared and red light passes through the tissues of a finger and the absorption of these lights can be measured by a photodiode. Depending on the quantity of oxygen in blood the ratio of absorbed red light and infrared light will be different and this ratio can be calibrated to measure the oxygen level in blood. The average value of every 10 samples is calculated and this is displayed on a LCD display. The actual measured redings can simultaneously transmitted using GSM module, to the remote caretaking person so that suitable actions can be taken on right time and many lifes can be saved.

A non-invasive technique for checking someone's oxygen saturation is pulse oximetry. Values of peripheral oxygen saturation (SpO2) are normally within 2% accuracy (within 4% accuracy in 95% of instances) of readings of arterial oxygen saturation (SaO2) from arterial blood gas analysis, which are more accurate (and intrusive). However, the correlation between the two is strong enough that the safe, practical, non-invasive, and affordable pulse oximetry approach is useful for determining oxygen saturation in clinical settings.

Transmissive pulse oximetry is the most popular method. In this method, a sensor device is applied to a narrow area of the patient's body, typically an infant's foot or an earlobe or fingertip. Heat transfer is facilitated by the greater blood flow rates in fingertip and earlobe tissues than in other tissues. Two wavelengths of light are sent from the device through the bodily part to a photodetector. It determines the absorbances caused by the pumping arterial blood alone, eliminating venous blood, skin, bone, muscle, fat, and, in most cases, nail polish, by measuring the changing absorbance at each of the wavelengths. A less popular alternative to transmissive pulse oximetry is reflectance pulse oximetry. This technique has several restrictions but works well for universal applications like the feet, forehead, and chest because it doesn't require a thin part of the subject's body. Vasodilation and venous blood pooling in the head as a result of impaired venous return to the heart can produce a mixture of arterial and venous pulsations in the area of the forehead and produce false SpO2 readings. Such circumstances can develop in patients in the Trendelenburg position or when under anaesthesia with endotracheal intubation and mechanical ventilation.A pulse oximeter is a medical device that measures changes in skin blood volume and the oxygen saturation of a patient's blood indirectly rather than directly through a blood sample. This results in a photoplethysmogram, which can then be processed to produce further readings. A multiparameter patient monitor may include a pulse oximeter. The majority of monitors also show pulse rate. There are also battery-powered, portable pulse oximeters available for use at home or while travelling.

In order to assess blood oxygen saturation continuously without invasive procedures, pulse oximetry is particularly practical. In contrast, a laboratory must analyse a blood sample before determining blood gas levels. Any setting where a patient's oxygenation is unstable can benefit from pulse oximetry, including intensive care, operating, recovery, emergency, and hospital ward settings, as well as pilots in unpressurized aircraft. It can assess any patient's oxygenation and determine whether additional oxygen is effective or necessary. A pulse oximeter can measure oxygenation, but it cannot assess how much oxygen a patient is using or how their metabolism of oxygen works.

Pulse oximeters are crucial in emergency medicine due to their ease of use and capacity to provide continuous and immediate oxygen saturation values. They are also extremely helpful for patients with respiratory or cardiac issues, especially COPD, as well as for the diagnosis of some sleep disorders like apnea and hypopnea. For the majority of the time spent trying to fall asleep, patients with obstructive sleep apnea will have pulse oximetry readings in the 70–90% range. Without losing the flow of patient data back to bedside monitors and centralised patient surveillance systems, connectivity developments now allow patients to have their blood oxygen saturation continually monitored without a cabled link to a hospital monitor. Pulse oximetry aids in the early identification of silent hypoxia in COVID-19 patients, a condition in which the patient appears to be comfortable but has a dangerously low SpO2. Patients either in the hospital or at home experience this. A severe COVID-19-related pneumonia with low SpO2 may necessitate a ventilator.

Brief description of Drawing
Figure 1 Block diagram of Oxialert device
Figure 2 Photograph of Oxialert device
Detailed description of the drawing
The details of the drawings are as follows:
Figure 1 gives the basic block diagram of the invented system, where different units of the invented device are presented.
Figure 2 shows the actual physician view of the invented oxialert device. Different functional units like measuring elements, display device, processing unit, GSM transmitter unit etc are included.
4 Claims & 2 Figures , Claims:The scope of the invention is defined by the following claims:

Claims:
1. The operation of the oxialert device comprises the following steps:
a) A predefined SpO2 is fed in the system and the health of the patient is continuously monitored.
b) The measured readings are continuously monitored and compared with the threshold level.
c) A GSM based alert system will be activated, if the SpO2 level falls below a pre-defined value
2. As per claim 1, the physical contact can be avoided by using the invented device for measuring the oxygen level in patients.
3. According to claim 1, the monitoring is continuous, where the concerned person’s oxygen level will be regularly observed.
4. As per claim 1, in a situation when the paitient having low blood oxygen readings the GSM based alert system will immediately inform the caretakers through SMS or Phone call.