Patent Application
20240050674
The present disclosure generally relates to resuscitators, particularly relates to manual resuscitators. More particularly, the present disclosure relates to systems and methods for controlling breathing parameters of a manual resuscitator, such as breathing rate, tidal volume, minute ventilation, breathing pace, inspiratory pressure, and inspiratory to expiratory ratio.
Respiratory failure generally presents itself in the form of respiratory insufficiency or complete respiratory arrest. Acute respiratory failure may lead to high morbidity and mortality rate if not treated early. The mortality rate for people with acute respiratory failure is between to 83% among in-hospital patients and even higher for out of hospital patients. The morbidity caused by acute respiratory failure is mainly due to low blood oxygenation, which may lead to extensive and irreversible destruction to brain, heart, and other organs.
Acute respiratory failure usually responds very well to early intervention. Patients who are treated early using artificial breathing devices have a high rate of survival and a good prognosis. In this regard, a simple manual breathing device is usually readily available to begin artificial breathing in an emergency. Bag-Valve-Mask devices are one of the most efficient and readily available manual breathing devices. Although bag-valve-masks have saved lives of many patients, it has recently been revealed that improper use of bag-valve-masks may lead to a high rate of mortality and morbidity as discussed in further detail below.
According to the latest guidelines of the American Heart Association (AHA), the artificial breathing rate is an important parameter determining the survival of patients with respiratory or cardio-respiratory arrest. The AHA has determined the optimum target rate of artificial breathing for adults with respiratory arrest as 10-12 breaths per minute. In addition, the breathing rate should be 2-10 breaths per minute for adults with cardiorespiratory arrest. The breathing rate differs for infants, children, and people with underlying diseases.
However, several studies have shown significant non-compliance between guideline recommendations and real practice. This non-compliance not only happens by the general public, or inexperienced members of the medical team but also by experienced medical personnel. For example, in one study it was revealed that even highly experienced paramedics were consistently ventilating cardiac arrested patients with breathing rates significantly higher than guidelines (i.e., hyperventilating patients). No rescuer in that study ventilated patients according to the guidelines, and they usually tended to ventilate patients with rates triple times or more than the recommended rates which substantially decreases the survival rates of the patients or causes irreversible life-long brain injuries.
The mechanism of the detrimental effect of hyperventilation during a respiratory arrest is partly understood. Hyperventilation contributes to increased intrathoracic pressure and may eventually lead to decreased heart coronary vessels' perfusion pressure, decreased cerebral perfusion pressure, induction of respiratory alkalosis, decreased cardiac output, loss of cerebrovascular autoregulation, brain cell hypoxemia, and initial and/or rebound increases in intracranial pressure in traumatic brain injury patients. The major problem is that all these detrimental effects are being inadvertently caused by medical teams and are not related to the main disease of a patient.
Previous attempts for preventing hyperventilation problem in bag-valve-masks were based on “educational methods”, “systems for controlling breathing rate”, and “cardiopulmonary resuscitation (CPR) metronomes”. Despite educational training sessions, literature still shows the tendency of even experienced rescuers toward inappropriate hyperventilation. Researchers believe that some reasons that may cause rescuers to ignore the guidelines and hyperventilate patients are the high levels of stress in the setting of an emergency visit of a (cardio)pulmonary arrested patient, complex processes of resuscitation that may cause human error in counting the breathing, and an impacted mental state of a rescuer encountering unstable vital signs of an arrested patient despite extensive resuscitation efforts.
Efforts to develop systems for controlling breathing rate has led to the development of electronic control devices having sets of sensors being placed in the airway of bag-valve-masks and providing information via different types of displays. These electronic systems may include various sensors; such as pressure sensors, flow-rate sensors, oxygen sensors, carbon dioxide sensors, alcohol sensors, and sensors for detecting probable drugs in a patients' exhalation. These control devices may measure various respiratory parameters such as airflow rate, breathing rate, breathing air pressure, and other relevant parameters.
Since sensors of the prior art control devices are placed in an airway of a bag-valve-mask resuscitator, they need to be sterilized before being used for each patient, otherwise they may transmit diseases between patients. The sterilization could be accomplished by either making whole control device or at least the sensors single-use. However, this may lead to a significant increase in the price of a control device. Since bag-valve-masks are being largely used in prehospital and in-hospital emergencies, even a slight increase in their price due to new technology may face rejection by health system managers.
On the other hand, the whole control device or at least sensors of a control device may be made reusable. However, due to the sensitive electronic structures of these control devices, they cannot be autoclaved using common pressurized high-temperature water steam autoclaves. In this regard, they require advanced sterilization methods such as gamma-ray, plasma, or ethylene oxide sterilization. These methods are expensive and require specialized equipment, not readily available in many healthcare facilities. Apart from the method of sterilization, the collection, and processing of a large number of these control devices for sterilization require specific logistics which adds a burden to the already complex logistics of healthcare facilities.
It should also be noted that in routine practice, during the transfer of patients by ambulances, bag-valve-masks are usually moved along with patients into hospitals. Since ambulance units in many regions are independent of hospitals, management of the reusable control devices utilized in bag-valve-masks would be challenging. In one scenario, a control device may be transferred along with a bag-valve-mask and a patient to a hospital. However, returning such a large number of control devices to ambulance services would be a complex and costly practice.
In another scenario, a control device may be detached from a bag-valve-mask during the handover of a patient from an ambulance to a hospital. However, the detachment of an intra-airway sensor would require major manipulation of a bag-valve-mask and consequent pause of the breathing of a (cardio)respiratory arrested patient. There also needs to be another device (compatible with the type of the bag-valve-mask being used) to be connected to the bag-valve-mask at the hospital. This practice may be considered as an unnecessary interruption of the resuscitation of a critically ill patient and may even have legal consequences.
Apart from the aforementioned sterilization issue, most of the prior art control devices may require a completely new design for a manual resuscitation device. In this context, introducing a completely new resuscitation device would be challenging from various points of view, such as acquiring medical permissions, proving their efficacy, introduction of a new device to the healthcare systems, changing users' minds to accept them as a new standard for resuscitation procedures, educating a large number of people on how to use the new resuscitation devices, and amending regulatory guidelines to consider these new resuscitation devices as accepted systems for breathing.
Furthermore, producing such new resuscitation devices require a significant change in current production lines of manufacturers and the future state of current millions of bag-valve-masks in markets and healthcare systems is unknown. Therefore, although using prior art systems might improve the quality of patients' resuscitation, the costs of introducing them to the medical community may not justify their benefits.
As mentioned before, a CPR metronome may be utilized to prevent hyperventilation problem. A CPR metronome is basically a ticking clock that produces audio or visual indications. For example, to deliver 20 breaths per minute, a CPR metronome may tick every 3 seconds. A user who is performing an intervention such as a cardiac massage or resuscitation utilizing a manual resuscitator is supposed to perform a single massage or resuscitation with each indication made by an exemplary CPR metronome. However, if a user fails to do so, a CPR metronome cannot compensate for a missed intervention. In real practice, a resuscitation process may be far more complex and there is no guarantee that a user can adjust themselves with a CPR metronome indication. For example, while a CPR metronome is ticking, in a first exemplary scenario, a user may be engaged with tasks other than giving respiration. In a second exemplary scenario, a user may be stressed out due to unstable vital signs of an arrested patient and may be desperately delivering excess numbers of respirations. In the first exemplary scenario, a CPR metronome may not compensate for a missed breath, and in the second exemplary scenario a CPR metronome may not produce an alarm for a user to stop hyperventilating. Furthermore, a CPR metronome may not be capable of evaluate quality of given ventilations. In an exemplary scenario, a user may not adequately squeeze the bag due to being tired of performing CPR for a while. In this exemplary scenario, a CPR metronome may not detect an improperly delivered breathing.
There is, therefore, a need for a simple and cost-effective control device that may be utilized in a currently available bag-valve-mask resuscitator without being installed in an airway of such bag-valve-mask resuscitator. There is further a need for a device that may evaluate quality and quantity of resuscitation breathings and provide real-time guidance to a user or a caregiver to achieve proper resuscitation parameters.
This summary is intended to provide an overview of the subject matter of the present disclosure and is not intended to identify essential elements or key elements of the subject matter, nor is it intended to be used to determine the scope of the claimed implementations. The proper scope of the present disclosure may be ascertained from the claims set forth below in view of the detailed description and the drawings.
According to one or more exemplary embodiments, the present disclosure is directed to a resuscitation management system for a manual resuscitator. An exemplary system may include a flex sensor and a processing unit. In an exemplary embodiment, the flex sensor may be configured to be attached to a resuscitation bag of the manual resuscitator. In an exemplary embodiment, the flex sensor may further be configured to conform a shape of the resuscitation bag during compression/decompression of the resuscitation bag. In an exemplary embodiment, the flex sensor may further be configured to measures an amount of bending of the flex sensor and generate an output signal indicative of the amount of bending of the flex sensor.
In an exemplary embodiment, the processing unit may be coupled to the flex sensor. In an exemplary embodiment, the processing unit may include at least one processor and at least one memory. In an exemplary embodiment, the at least one memory may be coupled to the at least one processor. In an exemplary embodiment, the at least one memory may store executable instructions to urge the processor to receive a plurality of output signals from the flex sensor.
In an exemplary embodiment, the processor may also associate each output signal from the plurality of output signals with a ventilation delivered to a patient responsive to the amount of deflection of the flex sensor being equal to or more than a predetermined threshold. In an exemplary embodiment, the at least one memory may also urge the processor to calculate a breathing rate by counting the delivered ventilations during a time interval.
In an exemplary embodiment, the flex sensor may be configured to be attached to an outer surface of the resuscitation bag of the manual resuscitator. In an exemplary embodiment, the flex sensor may be configured to be attached to an inner surface of the resuscitation bag of the manual resuscitator.
In an exemplary embodiment, the at least one memory may store further executable instructions to urge the one processor to calculate an extent of compression/decompression of the resuscitation bag at a first instance and an extent of compression/decompression of the resuscitation bag at a second instance, based on the output signal received from the flex sensor respectively at the first instance and the second instance. In an exemplary embodiment, the at least one memory may store further executable instructions to urge the at least one processor to calculate a speed of compression/decompression of the resuscitation bag as a function of time for a time interval based on the calculated extent of compression/decompression of the resuscitation bag at a first instance and the calculated extent of compression/decompression of the resuscitation bag at a second instance.
In an exemplary embodiment, the at least one memory may store further executable instructions to urge the at least one processor to associate each compression/decompression of the resuscitation bag with an adequate ventilation delivered to a patient responsive to the extent of compression/decompression of the resuscitation bag exceeding a predetermined threshold and calculate a breathing rate delivered to a patient in a time interval by counting adequate ventilations during the time interval.
In an exemplary embodiment, the at least one memory may further store executable instructions to urge the at least one processor to calculate an inspiratory to expiratory time (I:E) ratio and breathing pace based at least in part on the calculated speed of compression/decompression of the resuscitation bag as a function of time.
In an exemplary embodiment, the at least one memory may further store a calibration correlation between an extent of compression/decompression of the resuscitation bag at a given moment with a volume of breathing gases pushed out of the resuscitation bag at the given moment, the at least one memory further stores executable instructions to urge the at least one processor to calculate a tidal volume for each adequate ventilation delivered to the patient based on the calculated extent of compression/decompression of the resuscitation bag and the stored calibration correlation between the extent of compression/decompression of the resuscitation bag at a given moment with the volume of breathing gases pushed out of the resuscitation bag at the given moment.
In an exemplary embodiment, the at least one memory may further store executable instructions to urge the at least one processor to calculate a minute ventilation by calculating a sum of the calculated tidal volumes for the delivered ventilations in one minute. In an exemplary embodiment, the resuscitation management system may further include an input/output (I/O) interface. In an exemplary embodiment, the processing unit may further be coupled to the I/O interface. In an exemplary embodiment, the at least one memory may further store executable instructions to urge the at least one processor to provide information on the I/O interface based at least in part on a plurality of calculated breathing parameters. In an exemplary embodiment, the plurality of calculated breathing parameters may include the calculated breathing rate, the calculated I:E ratio, the calculated tidal volume, the calculated peak inspiratory pressure, and the calculated minute ventilation.
In an exemplary embodiment, the I/O interface may include at least one of a visual device, an audio device, a tactile device, and a mechanical device. In an exemplary embodiment, the information provided by the at least one of the visual device, the audio device, the tactile device, and the mechanical device may include one or more indications representing the plurality of calculated breathing parameters.
In an exemplary embodiment, the I/O interface may be configured to produce a plurality of indications. In an exemplary embodiment, the plurality of indications may include at least one of a visual indication, an audio indication, a tactile indication, and a mechanical indication.
In an exemplary embodiment, the mechanical device may include an attracting element and an attractable element. In an exemplary embodiment, the attracting element may include an electromagnet. In an exemplary embodiment, the attracting element may be configured to be mounted on the first side of the bag of the manual resuscitator. In an exemplary embodiment, the attractable element may include at least one of a permanent magnet, a ferromagnetic material, and an electromagnet. In an exemplary embodiment, the attractable element may be configured to be mounted on the opposite second side of the bag of the manual resuscitator. In an exemplary embodiment, the at least one memory may store executable instructions to urge the at least one processor to urge the attracting element to attract/repulse the attractable element by applying electrical currents of specific directions and strengths on at least one of the attracting element and the attractable element.
In an exemplary embodiment, the at least one memory may further store executable instructions to urge the at least one processor to urge the I/O interface to produce a first indication of the plurality of indications to guide a user to deliver a breathing at a certain instance.
In an exemplary embodiment, the at least one memory may further store a plurality of target breathing parameter ranges. In an exemplary embodiment, the plurality of target breathing parameter ranges may include a target breathing rate range, a target I:E ratio range, a target tidal volume range, a target peak inspiratory pressure, a target minute ventilation range, the at least one memory further storing executable instructions to urge the at least one processor to compare a calculated breathing parameter of the plurality of calculated breathing parameters with a corresponding target breathing parameter range of the plurality of target breathing parameter ranges.
In an exemplary embodiment, the at least one processor may further be urged to urge the I/O interface to produce a first indication of the plurality of indications responsive to the calculated breathing parameter being in the corresponding target breathing parameter range and urge the I/O interface to produce a second indication of the plurality of indications responsive to the calculated breathing rate being outside the target breathing parameter range.
In an exemplary embodiment, the at least one memory may store executable instructions to urge the at least one processor to determine an occurrence of hyperventilation based on at least one of the calculated breathing rate, calculated I:E ratio, calculated tidal volume, calculated peak inspiratory pressure, and calculated minute ventilation, the occurrence of hyperventilation corresponding to the calculated breathing rate, calculated I:E ratio, calculated tidal volume, calculated peak inspiratory pressure, and calculated minute ventilation being more than the target breathing rate range, target I:E ratio range, target tidal volume range, target peak inspiratory pressure, and target minute ventilation range, respectively, and urge the mechanical device to lock the bag by urging the attracting element and the attractable element to attract each other responsive to the occurrence of hyperventilation.
In an exemplary embodiment, the plurality of target breathing parameter ranges may further include subsets of the target breathing parameter ranges. In an exemplary embodiment, each subset of the subsets of the target breathing parameter ranges may be associated with at least one of an age group, a medical condition of a patient, a weight of a patient, and a patient type. In an exemplary embodiment, the I/O interface may further be configured to receive data from a user. In an exemplary embodiment, the data may include at least one of an age group, a medical condition of a patient, a weight of a patient, and a patient type.
In an exemplary embodiment, the at least one memory may further store executable instructions to urge the at least one processor to select a subset of the subsets of the target breathing parameters based on at least one of the received age group, the received medical condition of a patient, the received weight of a patient, and the received patient type, compare each calculated breathing parameter of the plurality of the calculated breathing parameters with a corresponding target breathing parameter range of the selected subset of the subsets of the target breathing parameter ranges, urge the I/O interface to produce a first indication of the plurality of indications responsive to each calculated breathing parameter of the plurality of calculated breathing parameters being in a respective target breathing parameter range of the selected subset of the subsets of the target breathing parameter ranges, and urge the I/O interface to produce a second indication of the plurality of indications responsive to each calculated breathing parameter of the plurality of the calculated breathing parameters being outside the respective target breathing parameter range of the selected subset of the subsets of the target breathing parameter ranges.
The novel features which are believed to be characteristic of the present disclosure, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following drawings in which a presently exemplary embodiment of the present disclosure will now be illustrated by way of example. It is expressly understood, however, that the drawings are for illustration and description only and are not intended as a definition of the limits of the present disclosure. Embodiments of the present disclosure will now be described by way of example in association with the accompanying drawings in which:
The novel features which are believed to be characteristic of the present disclosure, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following discussion.
The present disclosure is directed to exemplary embodiments of a system and method for resuscitation management that may be used for a manual resuscitator. An exemplary resuscitation management system may detect compression of a bag of a manual resuscitator and may associate each detected compression of the bag with a single breath delivered to a patient. An exemplary resuscitation management system may further generate an indication signal so as to provide information related to a breathing rate of a patient to a user. Such information may guide a user to achieve a target breathing rate. In an exemplary embodiment, achieving the target breathing rate may impact the survival chance of a patient and may prevent damages related to improper ventilation of a patient, such as brain damages. A user may be a rescuer or a caregiver who is utilizing a manual resuscitator to help a patient breathe. As used herein, air, gas, and breathing gases may be used interchangeably and may refer to gaseous materials that a person may inhale or exhale for the purpose of respiration and may either include a single chemical element or a combination of various chemical elements.
An exemplary resuscitation management system may include a sensor assembly that may be configured to detect a state of a resuscitation bag between a compressed state and a decompressed state. An exemplary sensor assembly may further be configured to detect an extent of compression of an exemplary resuscitation bag at any given moment during a resuscitation procedure. An exemplary resuscitation management system may be configured to receive a detected state of an exemplary resuscitation bag and data regarding the extent of compression of an exemplary resuscitation bag from an exemplary sensor assembly and associate each adequate compression of an exemplary resuscitation bag with a ventilation delivered to a patient. An exemplary adequate compression of an exemplary resuscitation bag may correspond to an extent of compression of an exemplary resuscitation bag that may allow for pushing out an adequate volume of breathing gases out of an exemplary resuscitation bag. An exemplary adequate volume of breathing gases may be determined based on the age, type, weight, and medical condition of a patient and relevant guidelines such as the latest guidelines of the American Heart Association (AHA).
An exemplary sensor assembly may include at least one of a flex sensor, and a pressure/tension sensor. An exemplary sensor assembly may be configured to generate an output signal indicative of a state of an exemplary resuscitation bag between a decompressed state and a compressed state, an extent of compression of an exemplary resuscitation bag, and a speed at which an exemplary state of an exemplary resuscitation bag changes between an exemplary decompressed state and an exemplary compressed state.
An exemplary resuscitation management system may further include a processing unit that may be coupled with an exemplary sensor assembly. An exemplary processing unit may be configured to receive an exemplary output signal from an exemplary sensor assembly and calculate breathing parameters such as a breathing rate, an inspiratory pressure, a minute ventilation, a tidal volume, and an inspiratory to expiratory time (I:E) ratio, based at least in part on an exemplary output signal or a plurality of exemplary output signals received form an exemplary sensor assembly. In other words, an exemplary processing unit may be configured to calculate breathing parameters such as a breathing rate, an inspiratory pressure, a minute ventilation, a tidal volume, and an I:E ratio, based at least in part on at least one of number of compressions in a given time interval, pressure of delivered air during inspiration, volume of delivered air during a given time interval, extent of each compression performed during a given time interval, and a speed at which an exemplary resuscitation bag is compressed.
An exemplary sensor assembly may be mounted on an outer surface of an exemplary resuscitation bag without any contact with contents of the bag. Such isolation of breathing gases from an exemplary sensor assembly may eliminate risks of improper sterilization of a sensor assembly. In practice, no contamination may enter a flow of breathing gas from an exemplary sensing assembly since there is no contact between the breathing gases and an exemplary sensor assembly. Furthermore, an exemplary sensor assembly mounted on an outer surface of a resuscitating bag may allow for an easy and quick removal or change of an exemplary sensor assembly, which may be beneficial from a practical standpoint. For example, an exemplary resuscitation management device may be mounted around an outer surface of an exemplary resuscitation bag by utilizing a flexible band. Such utilization of an exemplary flexible band to mount an exemplary resuscitation management device on an exemplary resuscitation bag may allow for easily and quickly mounting an exemplary resuscitation management device on resuscitation bags of various sizes. Furthermore, such flexible band mount may allow for easily and quickly removing an exemplary resuscitation management device by simply taking off an exemplary flexible band from around an exemplary resuscitation bag. In an exemplary scenario, such easy and quick removal of an exemplary resuscitation management device may be beneficial when an ambulance crew are handing over a (cardio)respiratory arrested patient to a hospital crew and need to quickly unmount their exemplary resuscitation management device from an exemplary resuscitation bag.
In an exemplary embodiment, an exemplary sensor assembly may include at least one flex sensor that may be mounted on an outer surface of an exemplary resuscitation bag. An exemplary flex sensor may be configured to sense a state of an exemplary resuscitation bag between a decompressed state and a compressed state based at least in part on an extent of bending of an exemplary flex sensor. An exemplary flex sensor may be bent at a first angle in an exemplary decompressed state of an exemplary resuscitation bag and at a second angle in an exemplary compressed state of an exemplary resuscitation bag. Consequently, an exemplary flex sensor may be configured to determine a state and an extent of compression of an exemplary bag based at least in part on the angle of an exemplary flex sensor at any given instance. An exemplary flex sensor may further be configured to calculate a compression speed of an exemplary resuscitation bag based on detected amount of change in the angle of an exemplary flex sensor for a given time interval.
In an exemplary embodiment, an exemplary sensor assembly may further include at least one pressure/tension sensor that may be mounted on an outer surface of an exemplary resuscitation bag. An exemplary pressure/tension sensor may be configured to sense the pressure inside bag 104 of manual resuscitator 102. An exemplary pressure/tension sensor may be configured to sense a state of an exemplary resuscitation bag between a decompressed state and a compressed state based at least in part on an amount of pressure exerted by a user's hand on an exemplary resuscitation bag during compression of an exemplary resuscitation bag. An exemplary pressure/tension sensor may be mounted on an exemplary resuscitation bag such that a user may press on an exemplary pressure/tension sensor to compress an exemplary resuscitation bag. An exemplary pressure/tension sensor may be configured to generate an output signal indicative of at least the amount of pressure sensed. An exemplary processing unit may then receive the output signal of an exemplary pressure/tension sensor and may utilize a calibration data to associate the amount of pressure with a state of compression of an exemplary resuscitation bag.
As mentioned before, such implementation of an exemplary sensor assembly that may be mounted on an outer surface of an exemplary resuscitation bag may allow for determining the compression/decompression of an exemplary resuscitation bag and then utilizing the determined compression/decompression state of an exemplary resuscitation bag by an exemplary processing unit to calculate breathing parameters, such as breathing rates. An exemplary resuscitation management system and device may utilize such calculated breathing parameters to help a user deliver correct amount of ventilation to a patient at appropriate time intervals so that any risks of hyperventilation or hypoventilation may be avoided.
In an exemplary embodiment, bag 104 may receive air or other breathing gases from a posterior flow channel 112 that may be connected to bag 104 via a posterior valve assembly 114. In an exemplary embodiment, posterior valve assembly 114 may include a diaphragmatic or a shutter valve that may be a one-way valve allowing air or other breathing gases into bag 104. In an exemplary embodiment, a reservoir bag (not illustrated) may further be connected to posterior flow channel 112 and may provide a large volume of air or other breathing gases to bag 104 via posterior valve assembly 114. As mentioned before, in an exemplary embodiment, a user, such as a rescuer or a caregiver may squeeze bag 104 to deliver air or other breathing gases to a patient via mask 106. When bag 104 is released by a user, bag 104 may be decompressed or self-inflated and fresh air or other breathing gases may refill bag 104 either through posterior flow channel 112 or other inlet tubes, such as inlet tube 116.
In an exemplary embodiment, manual resuscitator 102 may include any other type of patient airway interface other than mask 106, for example, an endotracheal tube or a laryngeal mask may further be used instead of mask 106. As used herein, a patient airway interface may refer to any kind of device that may connect manual resuscitator 102 to a patient's airway.
In an exemplary embodiment, each time bag 104 is squeezed by a user, one positive pressure flow of a breathing gas may be provided to a patient and may be counted as a single respiration or breath. In an exemplary embodiment, bag 104 may be squeezable or compressible by a user along axes perpendicular to a longitudinal axis 105 of bag 104. In an exemplary embodiment, longitudinal axis 105 may be an axis associated with the longest dimension of bag 104. For example, longitudinal axis 105 may extend along bag 104 between anterior valve assembly 110 and posterior valve assembly 114. As used herein, a positive pressure flow of air, a respiration, a breath, and an adequate ventilation delivered to a patient may be used interchangeably and may refer to delivering an adequate volume of breathing gases into a patient's lungs.
In an exemplary embodiment, manual resuscitator 102 may be of different sizes to fit different age groups, such as infants, children, and adults. For each age group, a proper range of breathing rate, inspiratory time to expiratory time (I:E) ratio, tidal volume, peak inspiratory pressure, and minute ventilation should be provided to a patient, where such proper breathing rate, I:E ratio, tidal volume, peak inspiratory pressure, or minute ventilation, are referred to herein as a target breathing rate, a target I:E ratio, a target tidal volume, a target peak inspiratory pressure, or a target minute ventilation, respectively. As used herein, a breathing rate range may refer to a number of respirations or breaths provided by manual resuscitator 102 per minute or other reference time periods. For example, 10 to 12 respirations per minute in an adult and 12 to 20 respirations per minute in a child may be considered as a target respiratory or breathing rate range.
In an exemplary embodiment, inspiratory pressure may refer to a pressure of air delivered to lungs of a patient with each breath by an exemplary manual resuscitator, conditional to no leak or block in manual resuscitator 102, and/or no leak or block in the interface between manual resuscitator 102 and the patient, during the operation of manual resuscitator 102. In an exemplary embodiment, peak inspiratory pressure may refer to the maximum pressure of air delivered to lungs of a patient during each breath by an exemplary manual resuscitator. For example, an inspiratory pressure of 25 to 30 cmH2O in an adult, or an inspiratory pressure of 20 to 25 cmH2O in a child may be considered as a target peak inspiratory pressure.
In an exemplary embodiment, I:E ratio may refer to the ratio between an inspiratory time and an expiratory time. For example, I:E ratio of 1:2 to 1:3 in an adult, or I:E ratio of 1:1.5 to 1:2 in an infant may be considered as a target I:E ratio. In an exemplary embodiment, tidal volume may refer to a volume of air delivered to lungs of a patient with each breath by an exemplary manual resuscitator. For example, a tidal volume of 500 to 600 ml in an adult, or a tidal volume of 100 to 200 ml in a child may be considered as a target tidal volume. In an exemplary embodiment, a minute ventilation may refer to a volume of gas inhaled or exhaled from a person's lungs per minute, or a volume of air delivered to lungs of a patient by an exemplary manual resuscitator per minute. For example, a minute ventilation of 5 to 8 liter in an adult, or a minute ventilation of 240 to 360 mL/kg in a child may be considered as a target minute ventilation.
In an exemplary embodiment, resuscitation management device 100 that may be mounted on an outer surface of bag 104 of manual resuscitator 102, may be configured to manage at least one of a respiration or breathing rate, an I:E ratio, a tidal volume, an inspiratory pressure, or a minute ventilation that may be provided by a user to a patient by utilizing manual resuscitator 102. In other words, resuscitation management device 100 may help a user to deliver at least one of a target respiratory or breathing rate, a target I:E ratio, a target tidal volume, a target peak inspiratory pressure, or a target minute ventilation to a patient, based at least in part on age group and medical condition of that patient. To this end, in an exemplary embodiment, resuscitation management device 100 may be configured to calculate at least one of a respiration rate or breathing rate, or an I:E ratio by counting the number of times and measuring the speed at which bag 104 is compressed by a user, and calculate at least one of a tidal volume, an inspiratory pressure, or a minute ventilation by measuring the extent of compression of bag 104 by a user, and then based at least in part on one of the calculated breathing rate, the calculated I:E ratio, the calculated tidal volume, the calculated inspiratory pressure, or the calculated minute ventilation may provide a user with audio, visual, tactile, or mechanical guidance as to how to proceed with the resuscitation process.
In an exemplary embodiment, resuscitation management device 100 may include a sensor assembly 101 that may be mounted on an outer surface of bag 104 of manual resuscitator 102. In an exemplary embodiment, sensor assembly 101 may include at least one of a flex sensor, and a pressure/tension sensor. In an exemplary embodiment, resuscitation management device 100 may further include a processing unit 118 and an input/output (I/O) interface 119 that may be coupled with sensor assembly 101. In an exemplary embodiment, resuscitation management device 100 may further include a flexible band 128, on which sensor assembly 101, processing unit 118, and I/O interface 119 may be attached. In an exemplary embodiment, flexible band 128 may be wearable around bag 104, such that sensor assembly 101 may be positioned on an outer surface of bag 104. In an exemplary embodiment, sensor assembly 101 may be attached on an inner side of flexible band 128 or an outer side of flexible band 128. In an exemplary embodiment, flexible band 128 may be made of at least two or more separate layers and sensor assembly 101 may be positioned between the at least two or more separate layers.
In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a speed of compression of the resuscitation bag based on the amount of change in the compression extent of the resuscitation bag over time and calculate an I:E ratio based at least in part on the calculated speed of compression of the resuscitation bag. In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a volume of breathing gases delivered to a patient in a single compression of the resuscitation bag (tidal volume) based at least in part on the determined extent of compression of the resuscitation bag. In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a minute ventilation based at least in part on the calculated breathing rate multiplied by calculated volume of breathing gases delivered to a patient in a single compression of the resuscitation bag. In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a minute ventilation based at least in part on the accumulation of calculated volumes of breathing gases delivered to a patient during a one-minute interval.
In an exemplary embodiment, resuscitation management system 200 may further include an input/output (I/O) interface 214 that may further be coupled to processing unit 204. In an exemplary embodiment, memory 212 may further store executable instructions to urge processor 210 to provide information on I/O interface 214 based at least in part on at least one of the calculated breathing rate, the calculated I:E ratio, the calculated tidal volume, the calculated inspiratory pressure, and the calculated minute ventilation. In an exemplary embodiment, I/O interface 214 may include a display, where the information provided on the display may include one or a combination of numbers representing the calculated breath rate and target breathing rate. In an exemplary embodiment, the information provided on the display may further include the calculated I:E ratio and the target I:E ratio, the calculated tidal volume and the target tidal volume, the calculated peak inspiratory pressure and the target peak inspiratory pressure, or the calculated minute ventilation and the target minute ventilation, alarm notifications, and a timeline showing the past, and upcoming breathing timepoints according to the calculated breathing rate.
In an exemplary embodiment, the I/O interface may include an alarm that may be configured to produce a plurality of one or more audio, visual, tactile, or mechanical indications. In an exemplary embodiment, memory 212 may further store a target breathing rate range and executable instructions to urge processor 210 to compare the calculated breathing rate and the target breathing rate range, urge the alarm to produce at least one of a first audio indication, a first visual indication, a first tactile indication, and a first mechanical indication responsive to the calculated breathing rate being in the target breathing rate range, and urge the alarm to produce at least one of a second audio indication, a second visual indication, a second tactile indication, and a second mechanical indication responsive to the calculated breathing rate being outside the target breathing rate range.
In an exemplary embodiment, memory 212 may further store a plurality of target breathing rate ranges, where each breathing rate range of the plurality of target breathing rate ranges may be associated with at least one of an age group, a medical condition of a patient, a weight of a patient, and a patient type. I/O interface 214 may further be configured to receive data from a user, where the data may include at least one of a user-defined target breathing rate, target I:E ratio, target tidal volume, target peak inspiratory pressure, target minute ventilation, age group, medical condition of patient, weight of a patient, and a patient type. In an exemplary embodiment, memory 212 may further store executable instructions to urge processor 210 to select a breathing rate range based on the received data from the user, compare the calculated breathing rate and the selected target breathing rate range, urge the alarm to produce at least one of a first audio indication, a first visual indication, a first tactile indication, and a first mechanical indication responsive to the calculated breathing rate being in the selected target breathing rate range, and urge the alarm to produce at least one of a second audio indication, a second visual indication, a second tactile indication, and a second mechanical indication responsive to the calculated breathing rate being outside the selected target breathing rate range.
In an exemplary embodiment, memory 212 may further store a target I:E ratio, a target tidal volume, a target peak inspiratory pressure, or a target minute ventilation associated with various patient types (human or animal), age groups, patient weights, and medical conditions. In an exemplary embodiment, memory 212 may further store executable instructions to urge processor 210 to select at least one of a target I:E ratio, a target tidal volume, a target peak inspiratory pressure, and a target minute ventilation based at least in part on at least one of the received age group, the patient type, the weight of the patient, and the medical condition of a patient, calculate at least one of an I:E ratio, a tidal volume, a peak inspiratory pressure, and a minute ventilation based on the received output signals from sensor assembly 202, compare at least one of the calculated I:E ratio, the calculated tidal volume, the calculated peak inspiratory pressure, the calculated minute ventilation with the selected target values of I:E ratio, tidal volume, peak inspiratory pressure, minute ventilation, and urge the alarm to produce at least one of an audio indication, a visual indication, a tactile indication, and a mechanical indication responsive to the calculated values being within selected target range or not.
In an exemplary embodiment, resuscitation management device 300 may include a sensor assembly similar to sensor assembly 202 that may include a plurality of sensors (301a-301d) that may be attached to a flexible band 306 similar to flexible band 128. In an exemplary embodiment, resuscitation management device 300 may further include a processing unit 310 similar to processing unit 204 and an I/O interface 312 similar to I/O interface 214. In an exemplary embodiment, processing unit 310 and I/O interface 312 may also be mounted on or attached to flexible band 306. In an exemplary embodiment, flexible band 306 may be mounted around resuscitation bag 308, such that plurality of sensors (301a-301d) may be positioned on an outer surface of resuscitation bag 308. In an exemplary embodiment, flexible band 306 may be mounted around resuscitation bag 308 to form a round enclosure around resuscitation bag 308 with a plane of the round enclosure perpendicular to a longitudinal axis 302 of resuscitation bag 308. As illustrated in
In an exemplary embodiment, as mentioned before, resuscitation bag 308 may be squeezed or compressed by a user along axes perpendicular to longitudinal axis 302 of resuscitation bag 308. For example, resuscitation bag 208 may be squeezed or compressed along axis 304a, axis 304b, or any similar axis perpendicular to longitudinal axis 302. For example, resuscitation bag 308 may be compressed along axis 304a to a compressed state 308′. In an exemplary embodiment, sensors (301a-301d) may be positioned on the outer surface of resuscitation bag 308 along such axes that are perpendicular to longitudinal axis 302. For example, sensors 301a and 301c may be mounted along axis 304a and sensors 301b and 301d may be mounted along axis 304b. In an exemplary embodiment, each sensor of plurality of sensors (301a-301d) may include a flex sensor, and a pressure/tension sensor. In an exemplary embodiment, sensors (301a-301d) may be similar or of different types.
In an exemplary embodiment, flex sensor 400 may have a first bend angle 406 and bent flex sensor 400′ may have a second bend angle 408. In an exemplary embodiment, an exemplary flex sensor may be structures as an elongated band that may be attached to an outer surface of resuscitation bag 308. In an exemplary embodiment, flex sensor 400 may conform to the shape of the outer surface of decompressed resuscitation bag 308 and may have a bend angle equal to first bend angle 406. In an exemplary embodiment, bent flex sensor 400′ may be bent in response to the outer surface of resuscitation bag 308 being bent due to the compression of resuscitation bag 308. In other words, bent flex sensor 400′ may conform to the shape of the outer surface of compressed resuscitation bag 308′ and may have a bend angle equal to second bend angle 408.
In an exemplary embodiment, an exemplary flex sensor may be configured to generate an output signal corresponding to a bend angle of an exemplary flex sensor. In an exemplary embodiment, when an exemplary flex sensor is bent, the resistance of the flex sensor may be changed. In an exemplary embodiment, the output signal may be generated as a function of the resistance of the flex sensor. For example, an exemplary flex sensor may be configured to generate a first output signal corresponding to an exemplary flex sensor being bent at first bend angle 406 and to generate a second output signal corresponding to an exemplary flex sensor being bent at a second bend angle 408. In an exemplary embodiment, an exemplary flex sensor may be configured to generate a plurality of output signals responsive to an exemplary flex sensor being bent between first bend angle 406 and second bend angle 408. Each output signal of the plurality of output signals may correspond to a bending extent of an exemplary flex sensor at a given moment during bending of an exemplary flex sensor between first bend angle 406 and second bend angle 408. In an exemplary embodiment, a rate at which a bend angle of an exemplary flex sensor changes between first bend angle 406 and second bend angle 408 in a given time interval may correspond to a speed of compression of an exemplary resuscitation bag. Furthermore, in an exemplary embodiment, bending extent of an exemplary flex sensor may be calibrated and correlated with a compression extent of an exemplary manual resuscitation bag.
In an exemplary embodiment, sensor assembly 202 may include a flex sensor that may be configured to generate an output signal indicating an extent of bending of an exemplary flex sensor. In an exemplary embodiment, memory 212 may store a calibration curve or a look up table that may correlate an extent of bending of sensor assembly 202 with an extent of compression of a resuscitation bag at any given moment. In an exemplary embodiment, memory 212 may include executable instructions to urge processor 210 to receive a plurality of output signals generated by sensor assembly 202 for a time interval, associate each output signal of the plurality of output signals at a given moment to an extent of compression of the resuscitation bag at the given moment utilizing the stored calibration curve or the look up table.
Different types of manual resuscitators used for infants, children, and adults may have resuscitation bags with different volumes at an uncompressed state. In an exemplary embodiment, memory 212 may store a lookup table to attribute each specific volume range of resuscitation bags with a specific type of manual resuscitators; for example, a bag volume range of 1400 ml to 2000 ml may be attributed to an adult manual resuscitator, and a bag volume range of 150 ml to 300 ml may be attributed to an infant manual resuscitator. In an exemplary embodiment, processor 210 may be configured to receive a first output signal from flex sensor 400 corresponding to the exemplary flex sensor being bent at first bend angle 406 that is mounted on an uncompressed bag 308 of a first manual resuscitator. In an exemplary embodiment, processor 210 may be configured to correlate first bend angle 406 with an extent of compression/decompression of bag 308. In an exemplary embodiment, memory 212 may further store a lookup table to correlate the extent of compression/decompression of a resuscitation bag with an estimate of the volume of the resuscitation bag. In an exemplary embodiment, processor 210 may be configured to estimate the volume of bag 308 of a first manual resuscitator at an uncompressed state and compare it with the volume ranges of different types of resuscitation bags in the lookup table in memory 212, and determine the type of the first manual resuscitator (i.e., infant-sized, child-sized, and adult-sized) based at least in part on the estimated volume of bag 308 of the first manual resuscitator at an uncompressed state being within the volume range of a specific type of resuscitation bags in the lookup table in memory 212.
In an exemplary embodiment, sensor assembly 602 may include a pressure/tension sensor that may be attached to an outer surface of resuscitation bag 608. In an exemplary embodiment, pressure/tension sensor as sensor assembly 602 may be configured to sense a state of resuscitation bag 608 between a decompressed state (designated by 608) and a compressed state (designated by 608′) based at least in part on an amount of pressure exerted by a user's hand on resuscitation bag 608 during compression of resuscitation bag 608. In an exemplary embodiment, sensor assembly 602 may be mounted on resuscitation bag 608 such that a user may press on sensor assembly 602 to compress resuscitation bag 608. In an exemplary embodiment, sensor assembly 602 may be configured to generate an output signal indicative of at least the amount of pressure sensed.
In an exemplary embodiment, memory 212 may further store calibration data to associate the amount of pressure within the time interval of exerting the amount of pressure, with an extent of compression of an exemplary resuscitation bag and executable instructions that may urge processor 210 to receive an output signal of sensor assembly 602 at a given moment and then may utilize the stored calibration data to calculate the extent of compression of resuscitation bag 608 at the given moment.
In an exemplary embodiment, memory 212 may further store a lookup table or calibration data related to the amount of pressure that is required to compress bag 104 of manual resuscitator 102 while it is not connected to a patient. In an exemplary embodiment, such compression of bag 104 of manual resuscitator 102 may refer to the extent of the compression of bag 104 that may deliver an adequate ventilation to a patient responsive to an extent of compression of the resuscitation bag exceeding a predetermined threshold. In an exemplary embodiment, the predetermined threshold may correspond to a 90±10% of the resuscitation bag being compressed, such that a volume of breathing gas equal to 90±10% of an internal volume of the resuscitation bag may be pushed out of the resuscitation bag. In an exemplary embodiment, the predetermined threshold may correspond to a volume of breathing gas in each inspiration that may be required for sustaining the life of a patient, corresponding to at least one of an age group, a medical condition of a patient, a weight of a patient, and a patient type. For example, a volume of breathing gas of 500 to 600 ml in each inspiration in an adult, or a volume of breathing gas of 100 to 200 ml in each inspiration in a child may be considered as the predetermined threshold. In an exemplary embodiment, such amount of pressure that is required to compress bag 104 of manual resuscitator 102 while it is not connected to a patient, may be referred to as a bag pressure constant.
In an exemplary embodiment, the bag pressure constant may be related to one or a combination of material of bag 104, shape/diameter of mask 106, shape/diameter of anterior flow channel 108, and shape/diameter of anterior valve assembly 110 of manual resuscitator 102. In an exemplary embodiment, the bag pressure constant may be related to the brand and/or model of a given manual resuscitator.
In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to self-measure a bag pressure constant for a specific resuscitation bag and store the self-measured bag pressure constant of the specific resuscitation bag in the lookup table in memory 212.
In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to retrieve the bag pressure constant from the lookup table based at least in part on one of a brand and/or model of a manual resuscitator 102, a self-measured bag pressure constant for a specific resuscitation bag, an age group, a medical condition of a patient, a weight of a patient, and a patient type. In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to receive a plurality of output signals from sensor assembly 602 indicative of at least the amount of pressure sensed during the operation of the resuscitation management device 100 for ventilating a patient. In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to select the highest value within the received plurality of output signals from sensor assembly 602 during a single inspiration, and correspond it to a measured peak compression pressure.
In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to deduct the bag pressure constant from the measured peak compression pressure, and associate the result of the deduction with a calculated peak inspiratory pressure which corresponds to the air pressure inside bag 104 of manual resuscitator 102 during an inspiration.
In an exemplary embodiment, memory 212 may store a lookup table to relate at least one of an age group, a medical condition of a patient, a weight of a patient, and a patient type with a target peak inspiratory pressure. In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to retrieve the target peak inspiratory pressure from the lookup table based at least in part on one of an age group, a medical condition of a patient, a weight of a patient, and a patient type, and compare the calculated peak inspiratory pressure with the target peak inspiratory pressure, and associate the result of the comparison with at least one of a lower-than-normal pressure, a normal pressure, and a higher-than-normal pressure of air delivered to a patient, responsive to the calculated peak inspiratory pressure being lower than, equal to, or higher than the target peak inspiratory pressure, respectively.
In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to associate the lower-than-normal pressure with a leak in manual resuscitator 102, and/or a leak in the interface between manual resuscitator 102 and the patient. In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to associate the higher-than-normal pressure with a block in manual resuscitator 102, and/or a block in the interface between manual resuscitator 102 and the patient. In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to associate the normal pressure with a normal integrity of the manual resuscitator 102 and/or a normal integrity in the interface between manual resuscitator 102 and the patient. In an exemplary embodiment, sensor assembly 602 may be a pressure/tension sensor unit that may be wrapped around resuscitation bag 608 as illustrated schematically in
In an exemplary embodiment, sensor assembly 602 may include a plurality of pressure/tension sensors that may be attached on different parts of an outer surface of resuscitation bag 608. For example, sensor assembly 602 may include pressure/tension sensors (601a-601c). In an exemplary embodiment, pressure/tension sensors (601a-601c) may include at least one of force-sensitive resistor pressure sensor, a linear soft potentiometer pressure sensor, a load cell, a capacitive trackpad, a capacitive touchpad, a piezoresistive strain gauge including a polysilicon thin film, bonded metal foil, thick film, silicon-on-sapphire, and sputtered thin film, a capacitive pressure sensor, an electromagnetic pressure sensors, a piezoelectric pressure sensor, an optical pressure sensor, and a potentiometric pressure sensor.
In an exemplary embodiment, resuscitation management system 700 may include a processing unit 702 similar to processing unit 204. In an exemplary embodiment, processing unit 702 may include at least one memory 704 similar to memory 212, and at least one processor 705 similar to processor 210 that may be coupled with memory 704. In an exemplary embodiment, processing unit 702 may further include a timer 706, an output assembly driver 708, an analog to digital (A/D) converter 710, a peripheral control interface driver 712, and a communication module driver 714. In an exemplary embodiment, resuscitation management system 700 may further include a sensor assembly 716 that may be similar to sensor assembly 202 and may be coupled to processing unit 702 via A/D converter 710. In an exemplary embodiment, resuscitation management system 700 may further include an output assembly 718 that may be coupled to output assembly driver 708, a peripheral control interface 720 that may be coupled to peripheral control interface driver 712, a communication module 722 that may be coupled to communication module driver 714. In an exemplary embodiment, elements of resuscitation management system 700 may be coupled with each other via a wired, wireless, or a combination of wired and wireless network, which is represented by connecting solid lines in
In an exemplary embodiment, memory 704 may be a computer-readable media or a volatile memory unit or a non-volatile memory unit. In an exemplary embodiment, memory 704 may be a hard disk, a floppy disk, a tape device, a flash memory data storage device, a thumb drive, a solid-state memory (SSD), a read-only memory (ROM), or an optical disk device, or any other similar memory devices or storage devices.
In an exemplary embodiment, memory 704 may be configured to store software, codes, or other forms of executable instructions that may be retrieved by processor 705 or other components of processing unit 702 to enable them to perform various functions. In an exemplary embodiment, each of the various components of processing unit 702, such as processor 705 may include internal storages to store their software instructions or codes to enable them to perform various functions without requiring memory 704.
In an exemplary embodiment, memory 704 may further contain reference tables including the limits of target values that may be used to compare or interpret the measurements received from sensor assembly 716. For example, memory 704 may include a target number of breaths per certain time intervals according to the determined type of patient (human or animal), target range of certain breathing parameters, such as I:E ratio, tidal volume, peak inspiratory pressure, or minute ventilation according to the determined type of a patient and medical condition of a patient. As used herein, determining a type for a patient may refer to determining if a patient is adult, child or infant and if a patient is a human or animal.
In an exemplary embodiment, memory 704 may further contain information and/or executable instruction to control the operation of the various components of processing unit 702, for example running various components of resuscitation management system 700, testing various components of resuscitation management system 700, such as testing the battery capacity, or calibrating various components of resuscitation management system 700.
In an exemplary embodiment, processing unit 702 may store all or part of the measured values throughout a resuscitation event performed by a manual resuscitation bag similar to manual resuscitator 102. In an exemplary embodiment, the stored values may include one or a combination of multiple parameters, such as the age of the patient (infant, child, adult), the type of the patient (human, animal), the time and date of the resuscitation event, the total number of breaths delivered to the patient, the total number of proper breaths delivered to the patient, the total number of improper breaths delivered to the patient, breathing rate at each time point; average breathing rate per certain time interval, retrieved values from a reference table that may be stored in memory 704, squeezing or compressing speed of bag 104 of manual resuscitator 102, duration of inspirations, duration of expirations, time interval between any inspiration and expiration, peak inspiratory pressure, mean inspiratory pressure during a certain time interval, or any other similar measured parameters by sensor assembly 716 or calculated parameters by processor 705.
In an exemplary embodiment, processing unit 702 may transfer the stored parameters on memory 704 to an external system, such as a computer, a tablet, or a mobile phone via communication module driver 714, or directly via communication module 722. Such stored history of measured and calculated data may be used for further evaluation of the quality of a given resuscitation event, or performance of a user during a resuscitation event. In certain cases, where a resuscitated patient may not survive, the history may provide evidence of an acceptable performance of artificial breathing, which may later be used to rule out hyperventilation or hypoventilation as a cause of death.
In an exemplary embodiment, peripheral control interface driver 712 may be connected to peripheral control interface 720 of resuscitation management system 700. In an exemplary embodiment, peripheral control interface 720 may be configured similar to I/O interface 214 of resuscitation management system 200 and may include touchscreens, buttons, switches, keypads, or potentiometers to let a user, such as a caregiver interact with processing unit 702 to initiate, continue or stop desired functions, or to input, alter, or delete at least one of the target values, the calculated values, or the calculated derivative values. In an exemplary embodiment, peripheral control interface 720 may be used to turn on or off resuscitation management system 700.
In an exemplary embodiment, memory 212 may further store a database of commercially available manual resuscitators and their associated parameters, such as their respective volumes, their respective bag pressure constant. In an exemplary embodiment, adjustment buttons (806a and 806b) may further be utilized to select a specific manual resuscitator from the stored database of commercially available manual resuscitators. In an exemplary embodiment, memory 212 may further store volumetric data for one-handed and two-handed compression of each respective commercially available manual resuscitators. Each commercially available manual resuscitator may have a specific internal volume and compressing an exemplary bag of a manual resuscitator by one hand or two hands may push out different volumes of breathing gases out of an exemplary bag. In an exemplary embodiment, such volumetric data for commercially available manual resuscitators and volumetric data for one-handed and two-handed compression of each respective commercially available manual resuscitator may allow for calculating various volumes of breathing gases delivered to a patient in various scenarios created due to utilizing different manual resuscitators and different types of compression (one-handed or two handed).
In an exemplary embodiment, memory 212 may further store executable instructions to urge processor 210 to calculate an extent of compression of an exemplary resuscitation bag 308 based at least in part on the amount of bending extent of an exemplary flex sensor mounted on exemplary resuscitation bag 308 at a given moment during bending of an exemplary flex sensor between first bend angle 406 and second bend angle 408, which correspond to a decompressed state and a compressed state of bag 308, respectively. In other words, for a given change in the bending extent of an exemplary flex sensor mounted on exemplary resuscitation bag 308 at a given moment between a decompressed state of exemplary resuscitation bag 308 with first bend angle 406, and a compressed state of exemplary resuscitation bag 308 with second bend angle 408, processor 705 may be configured to calculate how much an internal volume of bag 308 may change, based at least in part on volumetric data stored in memory 704 for each commercially available manual resuscitator.
In another exemplary embodiment, where there are more than one exemplary sensing elements such as sensing elements (301a and 301c or 601a and 601c), memory 212 may further store executable instructions to urge processor 210 to calculate an extent of compression of an exemplary resuscitation bag 308 based at least in part on the amount of relative displacement of the exemplary sensing elements (301a & 301c or 601a & 601c) mounted on exemplary resuscitation bag 308 between a decompressed state and a compressed state.
In an exemplary embodiment, memory 212 may further store a ‘bag compression-breathing volume’ curve that may provide information regarding a volume of a delivered ventilation based at least in part on an extent of compression of bag 104. As used herein, a bag compression-breathing volume curve may be obtained for each available manual resuscitator by calibration measurements. An exemplary bag compression-breathing volume may correlate an extent of compression of a bag to a volume of breathing gases pushed out of the bag for that extent of compression. For example, an exemplary compression-breathing volume may show how much breathing gas will be pushed out of a specific commercially available bag for a 50% compression of that specific commercially available bag. In an exemplary embodiment, memory 212 may further store two ‘bag compression-breathing volume’ curves for each commercially available manual resuscitator, one curve for a one-handed compression of a bag of the manual resuscitator and one curve for a two-handed compression of the bag of the manual resuscitator. For example, a bag compression-breathing volume curve for a one-handed compression of a commercially available adult Ambu Spur II manual resuscitator may show that a 50% one-handed compression of a bag of the adult Ambu Spur II manual resuscitator with a 1475 ml volume may deliver 500 ml of air into a patient's airways. In another example, a bag compression-breathing volume curve for a two-handed compression of a commercially available adult Ambu Spur II manual resuscitator may show that a 50% two-handed compression of a bag of the adult Ambu Spur II manual resuscitator with a 1475 ml volume may deliver 1100 ml of air into a patient's airways.
In an exemplary embodiment, memory 212 may further store executable instructions to urge processor 210 to calculate a tidal volume based at least in part on the stored ‘bag compression-breathing volume’ curves. In an exemplary embodiment, memory 212 may further store executable instructions to urge processor 210 to calculate a minute ventilation based at least in part on the calculated tidal volume and the calculated breathing rate.
In an exemplary embodiment, output assembly 718 may include one or a combination of multiple displays (810a, 810b, and 810c), at least one audio device 812, at least one tactile device, such as a vibrator (not illustrated), and at least one mechanical actuator. In an exemplary embodiment, multiple displays (810a, 810b, and 810c) may refer to two-dimensional monochrome displays, color displays, touch screens, liquid crystal displays, electronic paper, electrophoretic displays, electroluminescent displays, seven-segment displays, organic light-emitting diode (OLED or organic LED), or any other relevant visual device. In an exemplary embodiment, display 810a may display an optimal value for the breathing per minute based at least in part on the age group, patient weight, patient type, or a desirable breathing rate selected by a user.
In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to calculate time-intervals between compressions of bag 104 based at least in part on the target breathing parameters, such as the target breathing rate. For example, for a target breathing rate of 12 breaths per minute, processor 210 may calculate the time interval between each pair of consecutive compressions to be 5 seconds. In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to readjust time-intervals between compressions of bag 104 based on the performance of a user. For example, for a target breathing rate of 12 breaths per minute, responsive to a user having delivered only 5 breaths in seconds instead of 6 breathes, processor 210 may be configured to readjust the time interval between the remaining 7 breaths to achieve the target breathing rate of 12 breaths per minute. For example, the time interval between the remaining breaths for the next 150 seconds may be readjusted to ˜4.84 seconds to gradually achieve the target breathing rate of 12 breaths per minute within the next 2.5 minutes. In an exemplary embodiment, memory 212 may further store executable instructions to urge output assembly 718 to provide alarms corresponding to readjusted time intervals to guide a user to achieve target breathing parameters.
In an exemplary embodiment, display 900 may further display one or a combination of multiple values, such as an indication to show if the user is hypo-ventilating, normo-ventilating, or hyperventilating the patient, an indication to show the compression, or decompression of bag 104, an indication to show if the squeezing of bag 104 has been adequate to deliver a proper breathing; duration of compression or decompression of bag 104, compression/decompression speed, compression rate per minute or any arbitrary time interval, occurrence or non-occurrence of inspiration or expiration, calculated I:E ratio, target I:E ratio, elapsed time from the beginning of a resuscitation event, calculated tidal volume, target tidal volume, calculated minute ventilation, target minute ventilation, calculated peak inspiratory pressure, and target peak inspiratory pressure.
In an exemplary embodiment, display 900 may display a value, such as an exemplary value of current breathing rate per minute that is being delivered to a patient, and maybe an average of the number of the delivered breaths per certain time interval.
In an exemplary embodiment, output assembly 718 may further include one or more of monochrome light-emitting diodes (LEDs), multicolor LEDs, incandescent bulbs, surface mounted device (SMD) electroluminescent diode, or any other light-emitting elements. In an exemplary embodiment, audio device 712 may include a speaker, buzzer, piezo, or tone generator. In an exemplary embodiment, the tactile device may include one or a combination of pneumatic vibrators, electric vibrators, and hydraulic vibrators. In an exemplary embodiment, the vibrator may be an electric motor with an unbalanced mass on its driveshaft.
In an exemplary embodiment, output assembly 718 may provide alarms including one or a combination of multiple visual indications, such as light-emitting elements that are selectively turned on or turned off; audio indications that are generated by a speaker, buzzer, piezo, or tone generator; tactile indications that are generated by a vibrator; and mechanical indications that are generated by a mechanical actuator. In an exemplary embodiment, the alarm may be a lack of one or a combination of multiple visual indications, audio indications, tactile indications, or mechanical indications. For example, a visual, audio, or tactile signal may be generated continuously when there is no alarm, such as playing an audio signal of a certain frequency or a combination of various frequencies, when the user is using the bag-valve-mask in a target range of breathing parameters, such as delivering the target rate of breathing. In an exemplary embodiment, the alarm may be presented as a change in one or a combination of multiple visual indications, audio indications, or tactile indications. For example, a visual, audio, or tactile signal may change when there is an alarm, such as playing an audio signal of a different frequency, or a combination of various frequencies, when the user is not using the bag-valve-mask in a target range of breathing parameters (such as delivering a non-target rate of breathing).
In an exemplary embodiment, processing unit 702 may be configured to urge attracting element 1002 and attractable element 1004 to attract or repulse each other by sending command signals in the form of electric currents to attracting element 1002 and attractable element 1004. In an exemplary embodiment, processing unit 702 may be configured to manipulate polarities and strengths of magnetic fields generated by attracting element 1002 and attractable element 1004 by manipulating directions and amounts of the electric currents applied to attracting element 1002 and attractable element 1004. In an exemplary embodiment, attractable element 1004 may further include a magnetic element, such as a permanent magnet or a ferromagnetic material.
As mentioned before, in an exemplary embodiment, output assembly 718 may provide alarms by generating mechanical indications. In an exemplary embodiment, such mechanical indications may be generated by mechanical actuator 1003. For example, when a user is hyperventilating a patient, processing unit 702 may urge attracting element 1002 or attractable element 1004 to generate a magnetic field with a certain polarity and strength, such that attracting element 1002 and attractable element 1004 may attract each other to retain resuscitation bag 1006 in a compressed state (designated by dash lines and referred to by 1006′). In an exemplary embodiment, attracting element 1002 and attractable element 1004 attracting each other and thereby forcing resuscitation bag 1006 to remain in a compressed state in response to a user hyperventilating a patient, may allow for locking resuscitation bag 1006 and mechanically preventing the user to continue hyperventilation.
In an exemplary embodiment, peripheral control interface 720 may further be used to adjust other parameters and functions relevant to the operation of resuscitation management device 800, such as adjusting the target breathing rate, I:E ratio, tidal volume, peak inspiratory pressure, or minute ventilation, calibrating the sensor assembly, or muting output assembly 718. In an exemplary embodiment, the adjustments via peripheral control interface 720 may retrieve certain values from a reference table that may be stored in a memory of resuscitation management device 600, which may be configured similar to memory 704.
In an exemplary embodiment, processing unit 702 may further be configured to receive output signals of sensor assembly 716 and based at least in part on the received signals, initiate certain functions, such as turning on and off certain elements of resuscitation management system 700. For example, processing unit 702 may be configured to detect inactivity of the resuscitator, based at least in part on the received output signals of sensor assembly 716 and may initiate certain functions of resuscitation management system 700, such as presenting an alarm or turning off resuscitation management system 700, or even putting certain elements of resuscitation management system 700 to a low-power mode.
In an exemplary embodiment, utilizing such resuscitation management systems and devices similar to resuscitation management devices (100 and 800) or resuscitation management systems (200 and 700) may allow for determining if a manual resuscitator, such as manual resuscitator 102 is compressed or not, the duration of the compression, or the duration of lack of compression of bag 104; the speed of compression, or the speed of decompression of bag 104, number of compressions of bag 104, number of decompression of bag 104, rate of breathing per minute, rate of breathing during any arbitrary time intervals; measured peak inspiratory pressure; or occurrence or non-occurrence of an inspiration or an expiration during a certain time interval.
In an exemplary embodiment, processing unit 702 may further be configured to store all or part of the measured values throughout a resuscitation event in memory 704. As used herein, the measured values throughout a resuscitation event may be one or a combination of multiple parameters, such as the age group of a patient, type of a patient, time and date of the resuscitation event, total number of breaths delivered to the patient, total number of proper breathing delivered to the patient, total number of improper breathing delivered to the patient, breathing rate at each time point, the average breathing rate per certain time interval, the speed of the squeezing of a resuscitating bag, such as bag 104, duration of any inspirations, duration of any expirations, time interval between any inspiration and expiration, measured peak inspiratory pressure, target peak inspiratory pressure, and other similar parameters.
In an exemplary embodiment, processing unit 702 may further be configured to calculate a user's score, based at least in part on the relative percentage of a number of properly given breaths divided by a total number of the given breaths within a certain time interval. For example, if a total of 100 breaths are given within a 600 second time interval, and in which 90 breaths are counted as properly given breaths, then the processing unit 702 may calculate a 90% user's score. In an exemplary embodiment, processing unit 702 may be configured to count the number of the properly given breaths, based at least in part on the number of the given breaths with one or a combination of their calculated breathing parameters being within a certain range of their counterpart target breathing parameters. In an exemplary embodiment, the calculated breathing parameters being within a range of counterpart target breathing parameters may mean that the calculated breathing parameters being a certain amount larger than or smaller than their counterpart target breathing parameters. For example, the target peak inspiratory pressure may be 25 cmH2O for an adult, and the processing unit 702 may be configured to count any breaths with calculated peak inspiratory pressure being within 20% larger than or 20% smaller than the target peak inspiratory pressure, as the properly given breath; in which any breaths with calculated peak inspiratory pressure within 20 to 30 cmH2O may be counted as the properly given breath. In an exemplary embodiment, breathing parameters may include at least one of the breathing rate, the I:E ratio, the tidal volume, the peak inspiratory pressure, and the minute ventilation. Such calculation of the user's score may improve the training of users and may also enable healthcare systems to perform quality control of the resuscitation events.
In an exemplary embodiment, processing unit 702 may further be configured to transfer the aforementioned stored parameters to an external system, such as a computer, a tablet, or a mobile phone via the communication module driver 714, or directly via communication module 722. In an exemplary embodiment, such stored parameters may be used for further evaluation of the quality of a resuscitation event, or the performance of a caregiver during a resuscitation event. For example, in case a patient dies during a resuscitation event, the stored parameters may provide evidence that may be utilized in an investigation for cause of death.
In an exemplary embodiment, processing unit 702 may further be configured to receive new executable instructions, for reconfiguring the built-in operating system (BIOS), or the firmware, or the software of the components of resuscitation management system 700. Such new executable instructions may temporarily or permanently be stored on memory 704.
In an exemplary embodiment, LCR meter 1102 may continuously measure the inductance of inductive coil 1101 and generate an output signal indicative of the inductance of inductive coil 1101. In an exemplary embodiment, LCR meter 1102 may send the output signal to processor 210. In an exemplary embodiment, LCR meter 1102 may generate a plurality of output signals indicative of the inductance of inductive coil 1101 at different instances and send the plurality of output signals to processor 210. In an exemplary embodiment, memory 212 may store a lookup table or calibration curve to relate the inductance of inductive coil 1101 with area of inductive coil 1105 and thus with the area of a cross section of bag 104. In an exemplary embodiment, memory 212 may store a lookup table or calibration curve to relate the area of a cross section of bag 104 in a given instance with the volume of bag 104 at that given instance, which may also correspond to an extent of compression/decompression of a resuscitation bag at the given instance.
Different types of manual resuscitators used for infants, children, and adults may have resuscitation bags with different volumes at an uncompressed state. In an exemplary embodiment, memory 212 may store a lookup table to attribute each specific volume range of resuscitation bags with a specific type of manual resuscitators; for example, a bag volume range of 1400 ml to 2000 ml may be attributed to an adult manual resuscitator, and a bag volume range of 150 ml to 300 ml may be attributed to an infant manual resuscitator. In an exemplary embodiment, processor 210 may be configured to receive a first output signal from LCR meter 1102 corresponding to the inductive coil 1101 conforming to a shape of bag 104 of a first manual resuscitator, when bag 104 is in an uncompressed state. In an exemplary embodiment, processor 210 may be configured to correlate the received first output signal from LCR meter 1102 with the volume of bag 104 of the first manual resuscitator in the uncompressed state. In an exemplary embodiment, processor 210 may be configured to compare the volume of bag 104 of the first manual resuscitator in the uncompressed state, with the volume ranges of different types of resuscitation bags in the lookup table in memory 212, and determine the type of the first manual resuscitator (i.e., infant-sized, child-sized, and adult-sized) based at least in part on the estimated volume of bag 104 of the first manual resuscitator at an uncompressed state being within the volume range of a specific type of resuscitation bags in the lookup table.
In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to receive a plurality of output signals from LCR meter 1102, determine the extent of compression/decompression of a resuscitation bag at a given instance based on the received output signal at the given instance, associate a compression of a resuscitation bag with an adequate ventilation delivered to a patient responsive to the determined extent of compression of the resuscitation bag exceeding a predetermined threshold. In an exemplary embodiment, the predetermined threshold may correspond to a 90±10% of the resuscitation bag being compressed, such that a volume of breathing gas equal to 90±10% of an internal volume of the resuscitation bag may be pushed out of the resuscitation bag. In an exemplary embodiment, memory 212 may store a lookup table to relate at least one of an age group, a medical condition of a patient, a weight of a patient, and a patient type with the predetermined threshold. In an exemplary embodiment, memory 212 may store executable instructions to urge processor 210 to retrieve the predetermined threshold from the lookup table based at least in part on one of an age group, a medical condition of a patient, a weight of a patient, and a patient type, and may compare the extent of compression of the resuscitation bag with the predetermined threshold, and associate a compression of a resuscitation bag with an adequate ventilation delivered to a patient responsive to the determined extent of compression of the resuscitation bag exceeding the predetermined threshold. In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a breathing rate by counting the adequate ventilations delivered to a patient in one minute or any other reference times.
In an exemplary embodiment, processor 210 may be configured to receive the plurality of output signals form LCR meter 1102 and when the inductance of inductive coil 1101 is equal to or less than a predetermined threshold, processor 210 may associate the related output signal from the plurality of output signals to a ventilation delivered to a patient. In an exemplary embodiment, when bag 104 is compressed adequately and a ventilation delivered to the patient, area of inductive coil 1105 may become less than a first threshold and then the inductance of inductive coil 1101 may become less than a second threshold. In an exemplary embodiment, when inductance of inductive coil 1101 becomes less than the second threshold, it may mean that area of inductive coil 1105 may become less than the first threshold which may mean that bag 104 is compressed adequately and a ventilation delivered to the patient.
An exemplary adequate compression of an exemplary resuscitation bag may correspond to an extent of compression of the exemplary resuscitation bag that may allow for pushing out a volume of breathing gases from the exemplary resuscitation bag such that the volume of breathing gases may be adequate to sustain the life of a patient. The exemplary adequate volume of breathing gases may be determined based on the age, type, weight, and medical condition of a patient, and relevant guidelines such as the latest guidelines of the American Heart Association (AHA).
In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a breathing rate by counting the adequate ventilations delivered to the patient in one minute or any other reference time intervals.
In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a speed of compression of the resuscitation bag based on the amount of change in the compression extent of the resuscitation bag over time and calculate an I:E ratio based at least in part on the calculated speed of compression of the resuscitation bag. In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a volume of breathing gases delivered to a patient in a single compression of the resuscitation bag (tidal volume) based at least in part on the determined extent of compression of the resuscitation bag in a single compression of the resuscitation bag. In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a minute ventilation based at least in part on the calculated breathing rate multiplied by calculated volume of breathing gases delivered to a patient in a single compression of the resuscitation bag. In an exemplary embodiment, memory 212 may store further executable instructions to urge processor 210 to calculate a minute ventilation based at least in part on the accumulation of calculated volumes of breathing gases delivered to a patient during a one-minute interval.
In an exemplary embodiment, processing unit 702 may further allow to help train a trainee or an apprentice. In an exemplary embodiment, processing unit 702 may do so by being configured to provide feedback associated with different parameters of manual resuscitator 102 including, but not limited to, number of proper ventilations delivered to the patient, breathing rate, I:E ratio, tidal volume, calculated peak inspiratory pressure, and minute ventilation. In an exemplary embodiment, when processing unit 702 provides these feedback, the skill level of the trainee can be measured more easily and more precisely. Similarly, in an exemplary embodiment, processing unit 702 may further be configured to implement quality control on a real resuscitation process. In an exemplary embodiment, when processing unit 702 provides these feedback, quality control can be implemented on a resuscitation process that is done by a user.
In an exemplary embodiment, resuscitation management device 100 may be made in such a way that it could be put on the user's wrist like a watch, and when needed to be used for resuscitation of a patient, it could be taken off from the user's wrist and be mounted on bag 104 of a manual resuscitator.
In an exemplary embodiment, various frequencies may be used to excite the inductive coil 1101 and measure the inductance with LCR meter 1102. In an exemplary embodiment, to increase accuracy, a specific frequency could be selected having the least sensitivity to noise/interference in a given environment. For example, a first frequency may be used for resuscitation management device 100 that is intended to be used in ambulances, a second frequency may be used for resuscitation management device 100 that is intended to be used in an intensive care unit, and a third frequency may be used for resuscitation management device 100 that is intended to be used globally. In an exemplary embodiment, a range of excitation frequencies may be used, which might help further reduction of sensitivity to environmental noise/interference. In an exemplary embodiment, a fixed induction loop could be added to the circuit that can be used to remove noise/interference using some form of adaptive filter, relatively similar to the principle that may be used in commercial noise-cancelling headphones. In an exemplary embodiment, an electromagnetic shield may be used to reduce the sensitivity of LCR meter 1102 to environmental noise/interference.
The embodiments have been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed.
The foregoing description of the specific embodiments will so fully reveal the general nature of the disclosure that others can, by applying knowledge within the skill of the art, readily modify and/or adapt for various applications such specific embodiments, without undue experimentation, without departing from the general concept of the present disclosure. Therefore, such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It is to be understood that the phraseology or terminology herein is for description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in light of the teachings and guidance.
The breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments but should be defined only in accordance with the following claims and their equivalents.
Throughout this specification and the claims which follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not to the exclusion of any other integer or step or group of integers or steps.
Moreover, the word “substantially” when used with an adjective or adverb is intended to enhance the scope of the particular characteristic, e.g., substantially planar is intended to mean planar, nearly planar and/or exhibiting characteristics associated with a planar element. Further use of relative terms such as “vertical”, “horizontal”, “up”, “down”, and “side-to-side” are used in a relative sense to the normal orientation of the apparatus.
This application is a continuation-in-part of U.S. patent application Ser. No. 17/210,848, filed Mar. 24, 2021, and entitled “RESUSCITATION MANAGEMENT SYSTEM FOR MANUAL RESUSCITATORS”, which takes priority from U.S. Provisional Patent Application Ser. No. 62/993,728, filed on Mar. 24, 2020, and entitled “MANAGEMENT DEVICE FOR BAG-VALVE-MASK RESUSCITATORS,” which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62993728 | Mar 2020 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17210848 | Mar 2021 | US |
| Child | 18362544 | US |
