[001] The present invention relates to the field of ventilator. The present invention in particular relates to a system and method for single ventilator for multiple patients.
DESCRIPTION OF THE RELATED ART:
[002] Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or novel coronavirus which causes disease called corona virus disease 2019 (COVID-19). COVID-19 has been reported to cause pneumonia like symptoms in patients 1. Likewise, patients are unable to breathe properly due to which the exchange of oxygen (O2) and carbon dioxide (CO2) gets affected inside the alveolar cells. To overcome this problem patients are needed to put on ventilator support to inflate the lungs and fill them with fresh O2 so that the process of forced respiration can be achieved inside patient’s alveolar cells. Besides drugs and medicines, it makes ventilators a key medical device in recovering from this disease. But due to the rampant increase in the cases of COVID-19 there is a huge shortage of ventilators all around the world.
[003] As we have witnessed the mortality and morbidity caused because of the COVID-19 all over the world, the demand of ventilators has increased more than 10 times the production rate. Manufacturing companies are trying their best to cope up with the need of ventilator supply in the market. New and innovative ideas for rapid manufacturing of this medical device have emerged in a very short period of time. The idea of low-cost ventilators came from this analogy was made, to avail the ventilator support to those people who cannot afford the high-cost ventilators in the hospitals. But despite of increasing production rate and manufacturing the need of this medical device is still in high demand. The main problem which we have observed is in usability which is a single ventilator is being used for only one patient. Ventilator sharing, or dividing the airflow from one ventilator into multiple patients, has been previously performed in a few emergency cases. By using readily available tubing and ventilatory equipment, using this method immediate support can be given to the patients to and it is all done by just expand the capacity of existing ventilators with which clinicians are familiar. For example, The Neyman and Babcock Irvin solution of ventilator splitting. It involves connecting four patients to one ventilator by four sets of tubes connected to the ventilator using two, two-way splitters as one for the inspiratory and another for the expiratory limb. The splitter is made of three T-tubes and connection adapters. Despite of having such a great potential of reducing the death rate due to the current pandemic, the concept of splitting of ventilator has received widespread criticism. On March 26, 2020, a number of medical societies, including the Society for Critical Care Medicine, published a “Consensus Statement on Multiple Patients Per Ventilator” advising against the use of the technique, citing inherent risks. The major disadvantages they considered were: (i). inability to match ventilatory variables such as VT (Tidal volume), Fio2 (Fraction of inspired oxygen), and positive end-expiratory pressure (PEEP) to individual patient needs, and (ii). a change in respiratory mechanics in one patient would adversely affect ventilation to the co-ventilated patient(s). To tackle these factors and provide a solution to all these problems that were faced by the earlier ventilator splitting techniques and methods we came-up with the idea of ‘Centralized Ventilator System’, that we named I-Vent. It is a semi-portable, low-cost, easy-to-operate ventilator system that can be functional with multiple patients simultaneously. To maintain the individuality of the patients and to cope-up with the risk of cross contamination we have used five parallel breathing circuits along with their dedicated inhalation and exhalation valves.
[004] As we know, when we are using a single device to monitor multiple patients, patient’s vital monitoring becomes an important factor, therefore to accommodate this feature we have also used a dedicated sensor to track the heart rate (HR) and breathing rate (BR) along with the tidal volume (TV) of each patients individually. Also, we have designed an user interface with the help of a LCD display module to set and examine the different parameters of the patient’s vitals and variables. The initial current prototype can measure and regulate BR between 5-30 per minute, HR (Heart Rate), TV (Tidal Volume) of 200-800 mL, inspiratory and expiratory time ratio, i.e. I: E.
[005] Reference may be made to the following:
[006] IN Publication No. 202021025671 relates to a flow control multiplier system connectible to a contemporary medical ventilator so as to provide ventilation to multiple patients at the same time, characterized by flow control apparatus comprising a flow control multiplier unit a flow multiplier chamber and a control circuitry; a piping arrangement having a set of primary piping arrangement and a plurality of secondary flow piping arrangements consisting of a first flow piping arrangement, a second flow piping arrangement, a third flow piping arrangement, and at least up to a fourth flow piping arrangement; and a plurality of patient units. An operator sets ventilation parameters of individual patients. A sanitizing arrangement provided between the inhalation flow multiplier pipe unit and the exhalation flow multiplier pipe unit with a purge connector having a non-return valve.
[007] IN Publication No. 202027014950 provides system for monitoring spontaneous breathing of a mechanically ventilated target individual comprising: a feeding tube for insertion into a distal end of an esophagus of the individual, sensor(s) disposed on the feeding tube at a location such that the sensor(s) is located at the distal end of the esophagus of the individual when the feeding tube is in use, wherein the sensor(s) is positioned for sensing values by contact with the tissue of the esophagus including a lower esophageal sphincter (LES) and/or tissue in proximity to the LES, and code for computing an indication of a frequency band of diaphragm movement of the individual according to an analysis of values sensed by the sensor(s), and for adjustment of parameter(s) of a mechanical ventilator for mechanically ventilating the individual, wherein the instructions for adjustment are computed while the feeding tube is in use.
[008] IN Publication No. 202041036386 relates to internet of things based multi-functional ventilator. The ventilator comprises of a novel system of ambubag compression unit comprising of a set of movable compressor arms actuated in response to set I: E (inspiratory: expiratory) ratio. The present invention gives a multi-functional ventilator system integrated with IR sensor, ECG sensor and SpO2 sensor with a controller operably connected between the user interface and the ventilator system to communicate the detected sensor values in real time.
[009] Publication No. US2021299395 relates to an airflow switching valve allowing a single ventilator to sequentially ventilate multiple patients, each patient being ventilated through a respiratory cycle. The airflow switching valve includes an outer housing, an inner housing, and a spring. Each of the outer and inner housings have a plurality of apertures that, when aligned in different positions, direct airflow to different patients. The inner housing rotates within the outer housing into different positions. The rotational movement is guided by a track of the outer housing. Extensions on the inner housing engage the track of the outer housing and translate along the track, thereby directing the movement of the inner housing between varying positions. Movement of the inner housing is initiated by either a spring force caused by the spring of the airflow switching valve or by air pressure caused by an inspiratory breath flowing into the airflow switching valve from the ventilator.
[010] Publication No. WO2021189138 relates to a ventilator adaptor for converting a ventilator having an inspiratory port and an expiratory port from single patient use to multiple patient use is disclosed. The ventilator adaptor includes an inspiratory splitter, and expiratory splitter and a controller. The inspiratory splitter is attachable to the inspiratory port of the ventilator, and at least two inspiratory branches which are each connectable to a different patient. The expiratory splitter is attachable to the expiratory port of the ventilator, and at least two expiratory branches which are each connectable to the respective different patient. The controller separately controls at least one inspiratory parameter of an inspired fluid in each of the at least two inspiratory branches and/or at least one expiratory parameter of an expired fluid in each of the at least two expiratory branches. A ventilator system having the ventilator adaptor, and methods for ventilating at least two patients.
[011] Publication No. US2021322707 relates to a splitter module is configured to connect a single medical ventilator to multiple intubated patients. The splitter module is configured to independently control at least one ventilation parameter for each of the patients, such that modifying a ventilation parameter of one of the patients does not significantly affect the ventilation parameters of the other patients.
[012] IN Publication No. 202021015507 relates to a ventilator system and method for providing respiratory assistance to a patient. The system comprises an inspiratory manifold an inspiratory pump coupled to the inspiratory manifold for supplying gas to the patient. The system further comprises an expiratory manifold and an expiratory valve coupled to the expiratory manifold for allowing gas to expire from the patient. A pressure transducer is coupled to the inspiratory manifold for measuring a pressure of the gas inside the inspiratory manifold. A control unit is configured to continuously receive the measured pressure of the gas inside the inspiratory manifold and during an inspiratory cycle, control revolutions per minute (rpm) of the inspiratory pump; and during an expiratory cycle: control the expiratory valve to allow air to expire from the patient and at the same time control the revolutions per minute (rpm) of the inspiratory pump based on the received pressure of the gas inside the inspiratory manifold.
[013] IN Publication No. 202011019936 relates to discloses a ventilator device, including a ventilator supply system having a ventilator mask, two ambu bags, an air/oxygen source and an air/oxygen regulator system. A device of ventilator comprises the essential components: Two ambu bags, Linear Accelerators, A motor, Plurals of Drive, a Power supply, Stainless steel covers, Aluminum Base Plate, Rings; and a Aluminum Frame. A ventilator is a machine that provides mechanical ventilation by' moving breathable air into and out of the lungs, to deliver breaths to a patient who is physically unable to breathe, or breathing insufficiently.
[014] Publication No. PH22020050148 discloses a portable multi-patient medical ventilator that could be used simultaneously by multiple patients requiring assistance in breathing without cross contamination and is embodied by an enclosure, a low speed motor that drives a plurality of cams that alternately pushes a plurality of compressing plates that squeezes a plurality of medical breathing bags contained in individual compartments in said enclosure, a flow control valve disposed on a hose, wherein one end of said hose is disposed on the outlet of said medical breathing bag and the other end having a medical mask to cover the mouth and nose of a patient to facilitate his breathing.
[015] Publication No. US2013074844 discloses a mode of ventilation that makes an automatic determination of an appropriate mandatory breath type in response to one or more patient based criteria. Specifically, the ventilator during the delivery a mandatory breath type determines whether predetermined ventilatory criteria have been met. Based on the determination, the ventilator may deliver one of any number of mandatory breath types. Further, the present disclosure also combines the advantages of a hybrid mode of ventilation with this automatic determination of an appropriate mandatory breath type in response to one or more patient based criteria.
[016] Patent No. US6394089 relates to a patient ventilator oxygen concentration system advantageously utilizes an existing suitable air supply and provides a modular oxygen concentrator that uses the existing air supply and a medical grade air filtration package for providing medical grade using the existing air supply. The oxygen concentrator has multiple bed pairs which can be selectively activated. If one of the multiple bed pairs is not activated, the excess air provided by the existing air supply is filtered and medical grade air is supplied instead of oxygen gas for use with patient ventilators. Advantageously, the present invention obtains a large increase in medical grade air flow at the expense of very little oxygen flow while maintaining oxygen purity using the existing air supply. The present invention provides a pneumatic circuit which is capable due to a modular bed design. Each bed pair uses approximately three SCFM (80 SLPM) to produce five SLPM of oxygen. Shutting down a bed pair reduces the oxygen flow but increases the available compressed air to be converted into medial grade air. The remaining bed pair maintains their oxygen purity because the compressed air supply is not reduced.
[017] IN Publication No. 202241002660 provides noninvasive intermittent positive pressure ventilation. The apparatus includes a flow control unit including a first flow meter to provide a first predefined volume of medical air. The flow control unit includes a second flow meter to provide a second predefined volume of the medical air. The apparatus includes an inspiratory unit including a first valve to provide the first predefined volume of the medical air to a patient to assist an inspiration. The inspiratory unit includes a second valve to provide the second predefined volume of the medical air to the patient to assist expiration. The apparatus includes an expiratory unit to generate a peak inspiratory pressure. The expiratory unit is to generate a peak expiratory pressure. The apparatus includes a control unit to control the peak inspiratory pressure, the peak expiratory pressure thereby providing noninvasive intermittent positive pressure ventilation to the patient.
[018] IN Publication No. 202031050296 relates to a mechanical ventilator device. The mechanical ventilator device comprises, a bag valve mask (BVM), a stepper motor, a motor driver, a power source and a control unit coupled with the power source. The BVM delivers air into lungs of a patient, wherein the steeper motor periodically squeezes and releases the BVM in to deliver air into lungs of the patient. The motor driver modulates various operations of the stepper motor. The control unit coupled with the power source is configured to modulate the motor driver, wherein the stepper motor and the motor driver both run on power transmitted from the power source. The control unit is configured to dynamically trigger a control signal to the motor driver based on detected pressure by a flow sensor, wherein the motor driver in response to the triggered control signal automatically sets the rate of the stepper motor.
[019] IN Publication No. 4209/KOLNP/2015 relates to a modular ventilator the ventilator has modular flow control devices, which are connected to fluid inlet adapters. The modular flow control devices have sensors for controlling fluid flow through the modular flow control devices. The fluid inlet adapters are removable, and can include magnetic indicators, and the ventilator can identify the fluid from the magnetic indicator. The ventilator can also contain or be connected to a device having a low-noise blower.
[020] IN Publication No. 201711041445 provides a portable ventilator system for sensing respiratory phases and controlling the air supply from the integrated air ventilating module for a patient. The system is having a pressure sensor to sense the respiratory activities vis-à-vis an inhalation and exhalation respiratory phase of the patient, on sensing these phases, the patient needs to be provided the air supply according to that, which is further delivered by the integrated air pump under the controlled mechanism by a control module, this control module under supervision of a microcontroller. The microcontroller is also adapted to receive the input from a machine learning interface to deliver controlled air supply to the patient, which works in case the microcontroller is not able to receive the input values from the pressure sensing device. In addition, a portable computing device for keeping records of the respiratory phases in graphical form and can also interact with the microcontroller to determine the plurality of parameters for controlling air supply to the patient is also used.
[021] IN Publication No. 201827033958 relates to a ventilator system for providing respiratory support in cases of acute respiratory failure or severe trauma is described. The ventilator system comprises a ventilator and a tubing system. The system is characterized in that the ventilator comprises a continuous bleed valve configured to be open to air flow from the blower at all times when the blower is operating during both inspiration and expiration; thereby providing a minimal amount of pressure within a patient’s lungs at the end of each exhalation - positive end expiratory pressure (PEEP). In an embodiment of the invention the system comprises a manifold block configured to hold the main operating elements of ventilator.
[022] IN Publication No. 201711043364 provides a portable ventilator system for a patient. The system is having a pressure sensor to sense the respiration phase vis-à-vis an inhalation and exhalation respiratory phase of the patient, on sensing these phases, the patient needs to provide the air supply according to that, which is further delivered by the air integrated module under the controlled mechanism by a microcontroller. The microcontroller is also adapted to receive the input from a portable user device to deliver controlled air supply to the patient. In addition, the portable user device for keeping records of the respiratory phases in graphical form and can also interact with the microcontroller to determine the plurality of parameters for controlling air supply to the patient.
[023] IN Publication No. 202021016052 relates to a ventilator system comprising an oxygen delivery cylinder, an air delivery unit, connecting tubes, digital display unit. The system comprises a Y connector configured to mix air and oxygen, to form a gas and pass said gas towards an outlet of the system. A water manometer is configured to monitor a pressure of the gas in the system and blow off the excess pressure of the gas. A solenoid valve is configured to adjust an end respiratory pressure obtained from a breathing device connected to the outlet of the system. The pressure of the gas being instantly delivered to the breathing device is measured by water manometer from a dead space near the outlet, thereby enabling a dual monitoring of the gas pressure being delivered to the breathing device.
[024] Publication No. CN112691268 discloses a medical ventilator which comprises a plurality of air pump assemblies, each air pump assembly includes an air pump body and a second supporting base for supporting the air pump body, each air pump body comprises a pump body and a piston arranged in the pump body, a piston rod is connected to each piston, and when the piston rod acts, the piston is driven to pump air into the body of a patient; a drive mechanism; a transmission mechanism; wherein a one-way air inlet and a one-way air outlet which are controlled by a one-way valve are respectively formed in the air pumping end of the pump body, and the one-way air outlet is connected with a breathing mask worn on the mouth and nose of the patient through a connecting pipeline. The medical ventilator is simple in structure, the basic functions of a common mechanical ventilation type ventilator can be achieved, and the multiple air pump assemblies can be driven by one motor to be used by multiple patients.
[025] IN Publication No. 202017036338 relates to a medical tube transports gases to and/or from a patient. The medical tube includes a bead wrapped around a longitudinal axis of the medical tube. The bead forms a first portion of a lumen wall of the medical tube. The medical tube also includes a film wrapped around the longitudinal axis of the medical tube. A first portion of the film overlies the bead, and a second portion of the film forms a second portion of the lumen wall. The lumen wall, formed by the bead and the second portion of the film forms a substantially smooth bore. The medical tube can be reusable or reprocess able.
[026] Patent No. US7066173 relates to a system and method for monitoring the ventilation support provided by a ventilator and automatically supplying a breathing gas to a patient via a breathing circuit that is in fluid communication with the lungs of the patient.
[027] The article entitled “A single ventilator for multiple simulated patients to meet disaster surge” by Greg Neyman, Charlene Babcock Irvin; prolongedfieldcare.org; March 3, 2006 talks about the ventilator available in an emergency department that could quickly be modified to provide ventilation for four adults simultaneously. Using lung simulators, readily available plastic tubing, and ventilators human lung simulators were added in parallel until the ventilator was ventilating the equivalent of four adults. Data collected included peak pressure, positive end-expiratory pressure, total tidal volume, and total minute ventilation. Any obvious asymmetry in the delivery of gas to the lung simulators was also documented. The ventilator was run for almost 12 consecutive hours (5.5 hours of pressure control and more than six hours of volume control). Using readily available plastic tubing set up to minimize dead space volume, the four lung simulators were easily ventilated for 12 hours using one ventilator. In pressure control (set at 25 mm H2O), the mean tidal volume was 1,884 mL (approximately 471 mL/lung simulator) with an average minute ventilation of 30.2 L/min (or 7.5 L/min/lung simulator). In volume control (set at 2 L), the mean peak pressure was 28 cm H2O and the minute ventilation was 32.5 L/min total (8.1 L/min/lung simulator). A single ventilator may be quickly modified to ventilate four simulated adults for a limited time. The volumes delivered in this simulation should be able to sustain four 70-kg individuals.
[028] The article entitled “Single ventilator for multiple patients during COVID19 surge: matching and balancing patients” by Lonnie G. Petersen, James Friend & Sidney Merritt; Critical Care volume 24; 18 June 2020 talks about the potential COVID19-induced ventilator shortage, supporting multiple patients on a single ventilator seems a simple solution to maximize resources. Described by Neyman et al. this practice has anecdotally been used in the 2017 Las Vegas mass shooting and more recently in Italy and New York during the COVID-19 pandemic. However, a recent consensus statement from relevant medical associations discouraged the practice based on safety concerns. Beyond cross-contamination and increased dead space, matching patients to ensure appropriate individual ventilation peak pressures (Ppeak), tidal volumes (Vtidal), and positive end-expiratory pressures (PEEP) is a concern, especially given the dynamic clinical presentation of the COVID19 patients with complicated acute respiratory distress syndrome (ARDS). Frequent or constant monitoring of patients and shuffling when a mismatch arises is recommended. Asthma or COPD may increase the rate of fatal mismatch, making the method even more unpredictable. Finally, each class of ventilators requires a specific set up; if the method is considered, use the calm before the patient surge to familiarize, and ameliorate the many risks associated with sharing a ventilator.
[029] In order for a ventilator to be used for multiple patients there are many parameters that needs to be addressed. Such as, the PEEP, output volume, input volume, output pressure, input pressure, lung compliance, concentration of oxygen and carbon dioxide, to name a few.
[030] Conventionally many other attempts have already been done. A group in a hospital had tried to convert a CPAP machine into a positive pressure ventilator and used it to deliver fresh air to two patients at the same time by maintaining the pressure between the two distribution valves 4. Similar attempt was done by another group of people where they 3D printed a distribution valve and used the mechanical ventilators on a single pressure control mode and maintained respiration of four patients at the same time. But these attempts are not for longer duration of time and fails at critical cases where patients need intensive care or high ventilator support.
[031] In order to overcome above listed prior art, the present invention aims to provide a single ventilator for multiple patients which is low cost, portable and centralized ventilator system. In present system, every patient connected with the ventilator system is given a separate input and output respiration valves, pressure and volume of the input mixture of oxygen and air can be maintained according to the need of all the 5 patients connected to the system, individualized PEEP measurement and control, etc. With our system we are also providing SIMV, CPAP and BIPAP mode, which is till now not available in any other multi-patient ventilator in the market.
[032] This is achieved with the help of readily available assembly of valve and sensors. Sensors such as, pressure sensor, oxygen sensor, flow sensor, to name a few. The system can be modified into a multipatient ventilator according to the need. The breathing rate is sensed and controlled with two methods. First, with the help of flow sensors and verified with the help of the patients heartbeat rate.
OBJECTS OF THE INVENTION:
[033] The principal object of the present invention is to provide a single ventilator for multiple patients.
[034] Another object of the present invention is to provide a low cost, portable and centralized ventilator system to be used for more than one patient.
[035] Yet another object of the present invention is to provide centralized ventilator which can easily accommodate new modules and provide healthcare operators more information regarding a patient's breathing.
SUMMARY OF THE INVENTION:
[036] The present invention relates to a low cost, portable and centralized ventilator system to be used for more than one patient. The ventilator is capable of safely meeting the diverse ventilation requirements of COVID-19 patients because its parameters are adjustable over the broad ranges required for ARDS (Acute Respiratory Distress Syndrome) patients. The system focuses upon patient safety, simplicity of manufacturing and modularity. The system, can easily accommodate new modules that enable more sophisticated features, such as flow monitoring, which can enable additional ventilation modes and provide healthcare operators more information regarding a patient's breathing.
BREIF DESCRIPTION OF THE INVENTION
[037] It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments.
[038] Figure 1 shows statistics showing the number of COVID-19 cases and death around the world;
[039] Figure 2 shows working of the I-Vent;
[040] Figure 3 shows internal components of I-Vent; (a) Second prototype model of I-Vent and the; (b) Internal organization of components inside air and oxygen supply unit; (c) and exhalation or decontamination unit of I-Vent;
[041] Figure 4a ,4b, 4c and 4d shows working of controller unit and power supply unit.
DETAILED DESCRIPTION OF THE INVENTION:
[042] The present invention provides ventilator splitting by making a ventilator which can minimize the risk of cross-contamination and along with that maintain individuality of the patient by giving a centralized solution. The breathing rate (BR) is sensed by the breathing sensor and accordingly the ventilator delivers a certain volume of mixed O2 to the patient and takes the exhaled CO2 from him. Which is basically mimicking the functioning of the lungs of the body.
[043] The breathing rate is calculated using Photoplethysmogram (PPG) sensor and heart monitoring sensor. First the heart rate is calculated with the help of this sensor, and from that heart rate the breathing rate of the patient is calculated.
[044] With increase in heart rate there is significant change in the breathing rate also. So the difference factor between the HR and BR came out to be around 1/5 time the HR.
[045] For example, Let, HR = x beats per minute than,
BR = y ……….. eq.1
Then BR can be written as, y = x/5 per minute ………eq.2
[046] Now to calculate the inspiratory and expiratory time then needed to further elaborate these equations by calculating the time in seconds for one cycle of respiration, let it be represented by ‘z’.
From eq.2 z = 60/y ……….eq.3
[047] Now, eq.3 gives us the time in seconds for a single cycle of respiration.
Therefore, IT = z/2 ……..eq.4
ET = z/2 ……..eq.5
[048] Eq.4 and eq.5 gives the inspiratory time (IT) and expiratory time (ET) respectively within the single cycle of respiration.
[049] In present ventilator, solenoid valves play a very important role as they work both as control valve and flow valve in the ventilator. These valves work on a 12 volt of DC power supply and are controlled by a 5 volt low-power triggered relay module. The relay module controls the valve by switching the voltage according to the set BR in the form of digital signal fed by the Arduino Microcontroller.
[050] The system developed for the single patient can be seen in Figure.2. According to the test results it delivered mixed oxygen at a constant and set pressure between 10–50 cm H2O. It can sense the BR and it is also responding according to the change in the pressure at the end of the breathing circuit. This system works as expected, the necessary vitals like the body temperature, pressure inside the air cylinder and the relay rate can be seen on the LCD module attached in the front. The air compressor delivers a fresh amount of air with a pressure reading of 1 – 2 bar, which are measured inside the air compression cylinder with the help of a BMP180 barometric pressure sensor attached inside the cylinder. This air is channeled to the outlet cylinder with the help of a 12-volt Generic solenoid valve, and the valve itself is controlled by a 5-volt relay module. To replicate the working of a human lung, an extra valve for exhaled CO2 is also added on the other side of the breathing circuit. The BR rate as described earlier is sensed with the help of a SpO2 sensor. The output pressure of the inhaled air was 32cm H2O and can be changed according to need of the patient. The results gained from the first prototype was satisfying and we moved onto our next phase of the system that is making the system centralized.
[051] The ventilator comprises four main units:
1. Air and oxygen supply unit (1)
2. The exhalation unit (2)
3. Power supply unit (3)
4. Controller unit (4)
[052] The air and oxygen supply unit (Figure.3) consists of high-pressure air compressor (101), and an oxygen compressor cylinder (102), air and oxygen mixing chamber (103) and a couple of control valves (104) and check valves (105) in portable mode,
[053] The air compressor works as the air supply unit and fills the air compressor chamber with fresh air through a check valve, which is then pressurized to a certain pressure point. Similarly, oxygen is pressurized in the oxygen compressor chamber up to a certain pressure point. It is important to pressurize the oxygen and air in their separate chambers up to a certain level before mixing them in the outlet cylinder to get the exact amount of volume and pressure of mixed oxygen for each patient that is 35cm H2O, which is required for the process of respiration. From the Outlet cylinder, with the help of an outlet valve, which in our case is the Solenoid valve, mimics the respiration rate of the patient set by the operator and gives out a mixture of oxygen and air that is delivered to the patients' lungs using a ventilator air circuit through a CPAP (Continuous positive airway pressure) mask.
[054] The exhalation unit (2) having inlet cylinder (201) with inlet (202) and control (203) valves, takes the exhaled carbon dioxide from the patients through the inlet valve (Solenoid valve) (202), which is then collected in the inlet cylinder (201) and transferred safely outside through a bacteria-virus filter using a control valve (203) as shown in Figure.3. It doesn’t have a lot of components like the air and oxygen supply unit.
[055] Figure 4a shows the master (4) and slave controllers (401, 402) transferring and receiving data with the help of trans-receiver module (406). The power supply unit (3) as shown in figure 4b consists of the power supply circuits and other backup power systems with some alarms and indicators. The components used in this ventilator, the controller (301), valves, indicators (302), alarm systems (302), all of them work on a certain amount of voltage reading that is to be supplied in that specific amount only, otherwise the system may get faulty.
[056] Controller unit controls all the units and ensures the proper working of the ventilator. The system isbased on microcontroller device having sensor and relay module. This unit controls the pressure, temperature, and humidity of the supplied oxygen mixture and exhaled carbon dioxide with the help of some pressure, temperature, and humidity sensors (table 1). The relay module is a key component in the overall functioning of the system. Basically, a relay is an electromagnetic switch that turns ON and OFF when a certain control signal is given to its input terminal. The control signal, in our case, is the BR that is given by the microcontroller in the form of a digital pulse. This relay controls the inlet and outlet valves according to the digital signal given by the microcontroller. This makes the whole system to mimic the breathing of the patient.
[057] To prevent the system from excessive heating, proper ventilation of air is maintained. To prevent the failure of microcontroller, an additional microcontroller communication is provided. Dedicated microcontroller sets are provided for each patient and they are all synchronized with the master processor. There are many more changes and modifications has been done to prevent the ventilator from any kind of failures.
[058] Alarm and alert management system ensures patients safety. The system is capable of delivering 5-30 breaths per minute (bmp), peak inspiratory pressure between 10-100 cm H2O, inspiratory time between 1-4 seconds and a tidal volume between 200-800 ml. the volume alarms can be set for minima and maxima readings according to the patient’s health condition, age, weight, etc. The alert is displayed on the LCD module whenever there is a large fluctuation in the measured readings of the patient or if the reading crosses the set threshold value. There are volume and display alarm mounted on the device for any type of electrical or mechanical failure, gas sensor for any gas leakage, overheating, disconnection of any sensor, power leakage or disconnection alert. The alarm is audio, visual or can be send on user’s hand held device using communication media.
[059] As the BR is set by the doctor or examiner the set reading is stored in the microcontroller, where it waits for some microseconds. After this the BR that has been measured by the breathing sensor is sent to that location where both the readings are compared. If the comparison of BR fluctuates above or below the threshold than an alert is activated.
[060] The system is capable of delivering a set breathing rate (BR) between 5 – 30 beats per minute which can be set according to the physical condition of the patient. This set BR is crossexamined with the help of a SpO2 sensor, that senses the HR and according to which BR is calculated as shown in eq.3. The microcontroller compares these values and if the sensed BR is above or below the set BR the system is programmed to give alarms to the user. The whole system is tested on some test lungs and the results can be seen in Table.3. It shows the Heart rate (HR), calculated BR, inspiratory time, expiratory time for each test lung. Table.1 (fig 5).
[061] The tidal volume is calculated with the help of known air velocity, cross-sectional area of the valves and the inspiratory and expiratory time ratio. The system is able to deliver a tidal volume ranging between 200 to 800 mL for each patient with an inspiratory pressure ranging between 10 – 100 cm H2O.
[062] In an aspect the ventilator is especially for the patients with COVID-19 hence initially it only works on a single ventilator mode that is Pressure Control Volume (PCV) mode. In this mode, the pressure of the inspiratory mixed O2 is constant and volume of air and O2 mixture is regulated according to breathing rate of the patient.
[063] This is done because patients with COVID-19, needs an immediate amount of gas to be forced inside their lungs so as to maintain the respiration rate. This is called forced respiration.
[064] There is extra power backup mode which gets activated in case of any power cut. In case of any air supply failure or leak, the pressure sensor senses the drop or rise and give alerts to the controller which ultimately gives an alert to the user by flashing a message on the LCD module. Based on the current result analysis generated, the ventilator prototype can support ventilation of five patients and is reliable and safe to use after further testing in the hospitals and medical professionals.
[065] Thus the ventilator is capable of safely meeting the diverse requirements of COVID-19 patients because its parameters are adjustable over the broad ranges required for ARDS (Acute Respiratory Distress Syndrome) patients. The system focuses upon patient safety, simplicity of manufacturing and modularity. The system, can easily accommodate new modules that enable more sophisticated features, such as flow monitoring, which can enable additional ventilation modes and provide healthcare operators more information regarding a patient's breathing.
[066] Further any low cost ventilation system must take great care regarding providing clinicians with the ability to closely control and monitor tidal volume, inspiratory pressure, bpm, and I/E ratio, and be able to provide additional support in the form of PEEP, PIP Monitoring, filtration, and adaptations to individual patient parameters.
[067] To be used in intensive care units, mechanical ventilators must comply with the following three guidelines; they should allow users to set (i) the respiratory frequency (FR); (ii) the ratio of inspiration-to-expiration at each respiratory cycle (I:E); and (iii) the air volume supplied to the patient (Vt). When clinicians increase the I:E ratio in mechanical ventilators, they indeed increase the inspiration time within the respiratory cycle, which means that the lung receives more oxygen. Prolonged high levels of oxygen can cause alveolar overstretching, which triggers trauma. Pressure sensor can measure maximum differential pressure of up to 70 cm H2O. The clinician can set the I:E value through a rotary switch positioned at either 1:2 or 1:3. All experiments performed in the laboratory were taken for the I:E fixed at 1:2, Vt at about five breaths per minute, and FR at about 350 mL. It was noticed that there is about 0.02 Volts variability between consecutive breaths. From the engineering point of view, this variability may be related to a low frequency response to a periodic excited elastic-system like lung. This also validates the sensitivity of the used pressure sensor. If real-time measurements show values diverging from the reference value, fixed at 0.5 V, the system would trigger an alarm to alert clinicians for stopping the abnormal condition at earliest.
[068] Numerous modifications and adaptations of the system of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the true spirit and scope of this invention.

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WE CLAIM:

1. A single ventilator for multiple patients comprises-
a) Air and oxygen supply unit (1) characterized in that high-pressure air compressor (101), and an oxygen compressor cylinder (102), air and oxygen mixing chamber (103) and a couple of control valves (104) and check valves (105) in portable mode,
b) The exhalation unit (2) consist of inlet cylinder (201) with inlet (202) and control (203) valves, takes the exhaled carbon dioxide from the patients through the inlet valve (202) characterizing control and flow valve, which is then collected in the inlet cylinder (201) and transferred safely outside through a bacteria-virus filter using a control valve (203) K,
c) Power supply unit (3) with backup power system and power module for different voltage supply. There are many different voltage components that are used in this system and to maintain the proper voltage supply into the system this unit is used.Controller unit (4) having master (4) and slave controllers (401,402..) transferring and receiving data with the help of trans-receiver module (406) characterized in that sensors and relay module to control the pressure, temperature, and humidity of the supplied oxygen mixture and exhaled carbon dioxide with the help of some pressure, temperature, and humidity sensors wherein when the breathing rate (BR) is given by the controller in the form of a digital signal, relay controls the control valves, the inlet and outlet valves according to the digital signal given by the controller and makes the whole system to mimic the breathing of the patient.
2. The ventilator, as claimed in claim 1, wherein the air compressor works as the air supply unit and fills the air compressor chamber with fresh air through a check valve, which is then pressurized to a certain pressure point and oxygen is pressurized in the oxygen compressor chamber up to a certain pressure point and mixed them in the outlet cylinder to get the exact amount of volume and pressure of mixed oxygen for each patient that is 35cm H2O, which is required for the process of respiration and outlet valve, mimics the respiration rate of the patient set by the operator and gives out a mixture of oxygen and air that is delivered to the patients' lungs using a ventilator air circuit through continuous positive airway pressure mask.
3. The ventilator, as claimed in claim 1, wherein the controller compares the values and if the sensed breathing rate (BR) is above or below the set BR the system is programmed to give alarms to the user through controller.
4. The ventilator, as claimed in claim 3, wherein the alarm is audio, visual or can be send on user’s hand held device using communication media.
5. The ventilator, as claimed in claim 3, wherein the ventilator can easily accommodate new modules that enables additional ventilation modes and provide healthcare operators more information regarding a patient's breathing.