IT201900001915A1 - - Google Patents

Description

SYSTEM FOR THE DIAGNOSIS OF THE SYNDROME OF OSTRUCTIVE APNEE IN SLEEP (OSAS), PARTICULARLY OF THE TYPE

WITH POSITIONAL TREND

The present invention refers to a system for the diagnosis of obstructive sleep apnea syndrome (OSAS, from the English acronym "Obstructive Sleep Apnea Syndrome"), and in particular for the diagnosis of obstructive sleep apnea syndrome with positional tendency, defined P-OSAS (from the English acronym “Positional Obstructive Sleep Apnea Syndrome”).

Obstructive sleep apnea syndrome is characterized by the presence of repeated episodes of complete and / or partial and / or prolonged obstruction of the upper airways during sleep, associated with less oxygenation of the blood, which then results in multiple associated risks, what cardiovascular risks.

In addition, the obstructive sleep apnea syndrome manifests itself in the so-called excessive daytime sleepiness (also known as EDS from the English acronym "Excessive daytime sleepiness").

To date, the diagnosis of OSAS is based on a nocturnal polysomnographic study, also called polysomnography. The term polysomnography indicates a diagnostic study that involves the simultaneous recording of several vital parameters during night sleep, such as heart rate, blood oxygenation (oximetry saturation), nasal and / or oral airflows, expansion thoracic and abdominal, brain traces, etc.

The polysomnography is carried out by means of an instrument, called polysomnograph, which integrates a plurality of different sensors connected to the patient, for the detection of one or more of the aforementioned vital parameters.

Currently, 4 types of polysomnography can be identified, based on the type of diagnosis required:

• Type I - Complete polysomnography in the laboratory: it requires one night in hospital and a technician who supervises the instrumentation, the patient and the vital signs that are recorded throughout the night. In this type of polysomnography, a wide range of vital parameters are detected, including, in particular, the electroencephalogram (EEG). With this examination all sleep disorders can be thoroughly investigated, mostly in the neurological field with particular attention to the hypnic structure of sleep. By requiring hospitalization and the presence of a specialized technician, this type of diagnosis has limited use and indications, and high costs.

• Type II - Complete outpatient polysomnography: this type of polysomnography uses essentially the same sensors as type I polysomnography, but does not require hospitalization or a specialized technician to supervise the instrumentation. It can also be performed at home. The areas of investigation are the same as for type I, that is, all sleep disorders, with particular attention to the neurological area.

• Type III - Cardiorespiratory polysomnography:

it is currently the most used and the most widespread for the diagnosis of OSAS, snoring and obstructive apnea. This type of polysomnography does not require hospitalization and is performed at home. It has a reduced number of sensors compared to types I and II, since it does not investigate or study the neurological and / or hypnic structure of sleep, in fact, electroencephalographic derivations are not used. The sensors generally include a nasal cannula for detecting nasal airflow, a pulse oximeter on the finger that records the oximetry saturation and obtains the heart rate, a chest expansion sensor and an abdominal expansion sensor, consisting respectively of a chest strap. and an abdominal band, for the detection of the respiratory phases. This is a night study aimed at highlighting obstructive respiratory problems, such as snoring associated with obstructive apnea - OSAS, but not of a neurological type.

• Type IV - Pulse oximetry: in this case, only the heart rate and oximetry saturation are recorded, by means of a sensor on the patient's finger. To date, however, as can be clearly seen from the scientific literature, this survey cannot and must not be used for the diagnosis of OSAS or obstructive apneas, but only for monitoring and / or screening purposes.

Within OSAS, obstructive sleep apnea with positional tendency (P-OSAS) can be considered a very frequent subgroup of OSAS, in which the patient significantly varies vital parameters and polysomnographic indices, often in a pejorative sense. in relation to the position taken during sleep (hence the name of "positional syndrome").

The patient with P-OSAS therefore suffers from a "dynamic" nocturnal respiratory disorder, which can be triggered or worsened depending on the position assumed during sleep.

It is therefore clear how important it is in these cases to define the exact position taken by the patient during sleep, especially during the polysomnographic study.

In fact, it is only on the basis of a precise definition of the position taken by the patient, correlated to the polysomnographic severity indices, such as the AHI (from the English acronym "Apnea Hypopnea Index") that defines the number of apneas and hypopneas per hour of sleep, that the medical problem can be precisely diagnosed and a correct treatment of the P-OSAS syndrome can be set up.

Known polysomnographs consist of a portable device that can be fixed to the patient's chest, to which the devices for detecting the vital parameters mentioned above are connected (e.g., pulse oximeter, nasal cannula, thoracic belt, abdominal belt). Often known polysomnographs also include a position sensor integrated in the device itself, and therefore applied to the patient's chest, just below the pectoral muscles.

These position sensors are configured to distinguish, on the basis of the rotation position of the chest, only a limited number of patient positions: supine decubitus, right or left lateral decubitus at 90 ° or standing position.

Known polysomnographs are not free from drawbacks, including the fact that they are able at most to detect only the position of the patient's chest, and in any case they only allow to know if the patient is supine or in lateral decubitus. At a diagnostic level this is a major limitation, in particular for the diagnosis of OSAS with a positional tendency, as explained below.

Apneas and hypopneas are developed at the level of the "upper" respiratory tract, ie at the level of the head and neck, and not at the thoracic level. In addition, the thorax is anatomically free, in its movements, from the movements that can independently assume both the neck and the head.

Detecting the position of the chest alone does not in any way provide information on the position that both the head and the neck can assume at the same time during sleep.

With the current polysomnographs, up to now only the position of the chest has been detected as representative of the real position of the patient, also for the purpose of diagnosing P-OSAS which, as mentioned, are also strongly dependent on the position of the head and neck.

The current diagnostic mode with detection of the thoracic position alone can lead to diagnostic errors which are therefore currently significantly underestimated. For example, the patient may have the thorax in the supine position, but the head rotated in the lateral position: in this position, during a polysomnographic recording, an erroneous signal of the patient's supine position is obtained when the head and neck are instead in position. of lateral decubitus.

Taking into account, as mentioned before, that obstructive apneas do not develop at the level of the thorax, but in the upper anatomical regions, contained in the head and neck, the absence of information relating to the independent position assumed by the head and neck during Obstructive apnea episodes inevitably leads to diagnostic errors and subsequently to the definition of therapeutic treatments that are not completely effective.

The aim of the present invention is to provide a system for diagnosing obstructive sleep apnea syndrome (OSAS), particularly of the type with a positional tendency, which overcomes the limits of the known art, allowing more reliable and repeatable diagnoses to be obtained.

Within the scope of this aim, an object of the present invention is to provide a diagnostic system for OSAS which allows to carry out diagnoses which suitably take into account the different position assumed by the patient during sleep, with particular attention to the specific and independent movements of the three body segments: chest, neck and head.

A further object of the invention is to provide a system for diagnosing OSAS which is capable of giving the greatest guarantees of reliability and safety in use.

Another object of the invention is to provide a system for diagnosing OSAS which is easy to set up and to use, if compared to the known art.

The aforementioned aim, as well as the aims mentioned and others which will appear better later, are achieved by a system for the diagnosis of obstructive sleep apnea syndrome (OSAS), particularly of the type with a positional tendency, as stated in claim 1.

Other features are provided in the dependent claims.

Further characteristics and advantages will become clearer from the description of a preferred, but not exclusive, embodiment of a system for the diagnosis of obstructive sleep apnea syndrome (OSAS), particularly of the type with a positional tendency, illustrated for illustrative and non-limiting purposes. with the aid of the attached drawings in which:

Figure 1 schematically illustrates an embodiment of a system for diagnosing obstructive sleep apnea syndrome (OSAS), particularly of the type with a positional tendency, according to the invention, applied to a patient;

Figure 2 schematically illustrates the main components of the system of Figure 1, according to the invention;

figure 3 shows a representative table of all the positions of the thorax detectable by the system according to the invention;

Figure 4 shows a table representing all the positions of the garment which can be detected by the system according to the invention;

figure 5 shows a representative table of all the positions of the package detectable by the system according to the invention;

Figures 6 and 7 illustrate two examples of different positions that the neck and head can assume with respect to the chest.

The system for the diagnosis of obstructive sleep apnea syndrome (OSAS), particularly of the type with a positional tendency, is globally indicated with the reference number 1.

According to the invention, the system 1 comprises at least three position sensors 2, 3, 4 applicable respectively to the following three body segments of a patient P: the head H, the neck N and the chest C. These at least three position sensors 2, 3, 4 are suitable for detecting the position of the aforementioned three body segments H, N, C during the sleep of patient P.

The term "position sensor" generally refers to a device capable of carrying out a measurement, direct or indirect, of position, absolute or relative, of linear and / or angular type, according to one or more axes.

Advantageously, therefore, the system 1 is able to simultaneously detect the position and movement of the head H, the neck N and the thorax C.

The chest C, the neck N and the head H have in fact the possibility of making independent movements. During sleep, the patient P can assume, with reference to these three body segments mainly involved in respiratory acts, a position defined by any combination of positions that can be assumed by said three body segments.

The anatomical regions contained in the head and neck are precisely those where obstructive nocturnal apneas take place anatomically and mechanically. Although obstructive nocturnal apneas do not occur in the chest, it is still useful to detect the position and / or movement of the chest as well, since the position of the chest can affect the position in the space of the head and neck, regardless of the movements of the latter.

Advantageously, the system 1 comprises at least one sensor 5 suitable for obtaining the heart rate and / or the oximetry saturation of the patient P during sleep.

This sensor 5 can be a pulse oximeter applied non-invasively to a finger of patient P. The pulse oximeter is capable of obtaining both information on the heart rate of the patient P and on the oximetry saturation of the blood.

Advantageously, the system 1 can comprise at least one vibrating device 20, 30, 40 applicable to at least one of the three body segments (head H, neck N, thorax C). This vibrating device 20, 30, 40 can be activated according to the position of at least one of the three body segments H, N, C detected by one or more of the three position sensors 2, 3, 4 during the sleep of the patient P.

In this way, starting from a diagnosis of OSAS with a positional tendency, it is possible to use system 1 also for therapeutic purposes.

For example, if it is found that a certain position of one or more of the three body segments H, N and C of the patient P, or even a certain position of the patient given by a specific combination of positions of the three body segments H, N and C , is associated with pathological positional apneas, it is possible to provide a disturbing signal to patient P, for example a vibration of progressive intensity, to dissuade patient P from maintaining that position.

Preferably, the vibrating device 40 is applied to the chest C of patient P.

To dissuade the patient P from maintaining an unwanted position, it is possible to provide for the presence of a plurality of vibrating devices 20, 30, 40 arranged respectively on the head H, on the neck N and on the chest C.

In this way, it is possible to select which of the three body segments H, N, C to stimulate, according to the detected position of the same.

In fact, in some positions of patient P it may be more useful to stimulate only the head H or the neck N of patient P, to force him to change the relative position of the body segments H, N, C without the patient P waking up.

Furthermore, in this way it is also possible to stimulate the patient P, by means of a localized vibration, precisely in correspondence with the body segment H, N, C which is assuming an undesired position.

Advantageously, the three vibrating devices 20, 30, 40 can be integrated in the position sensors 2, 3, 4.

The system 1 therefore also assumes a therapeutic function as it detects in real time an undesirable situation for the patient, such as a pathological position of the head or neck, and stimulates him to get out of this undesirable situation, for example by moving his head or neck. neck.

The system 1 can advantageously comprise a thoracic belt 6 suitable for detecting the thoracic expansion of the patient P and an abdominal belt 7 suitable for detecting the abdominal expansion of the patient P. In this way it is possible to trace the trend of the inspiratory and expiratory acts. of patient P.

Advantageously, the system 1 can comprise a sensor 8 for detecting the nasal and / or oral airflow of patient P.

This sensor 8 can be a nasal cannula or a gold / nasal cannula.

Advantageously, the system 1 can comprise a plurality of electrodes for detecting the electrical signals of the patient P.

For example, the system 1 may comprise an electroencephalograph adapted to detect the brain electrical trace of the patient P (electroencephalogram - EEG). In this case the system 1 therefore also includes electroencephalographic leads.

Advantageously, the system 1 can also include an electromyograph (EMG) to detect the muscle activation of appropriate muscle groups of patient P.

Advantageously, the system 1 can also include electrocardiographic leads for the detection of the electrocardiogram (ECG) of patient P.

The system for the diagnosis of obstructive sleep apnea syndrome (OSAS), in its basic embodiment, ie provided with only the three position sensors 2, 3, 4, can be suitably used in nocturnal polysomnographic studies. In fact, this system can be suitably integrated into existing polysomnographs, after their hardware and software reconfiguration.

Similarly, the system for the diagnosis of obstructive sleep apnea syndrome (OSAS), in its basic embodiment, i.e. equipped with only the three position sensors 2, 3, 4, can be associated with existing pulse oximeters for purposes monitoring and / or screening of patients, also in this case after hardware and software reconfiguration of the pulse oximeters.

In other words, the system for the diagnosis of obstructive sleep apnea syndrome (OSAS), in its basic embodiment, i.e. equipped with only the three position sensors 2, 3, 4, can be integrated into existing diagnostic solutions, possibly with appropriate adjustments or additions or software and hardware updates of the tools already available today.

As illustrated in Figures 1 and 2, the system 1 can comprise a central unit 9 configured to receive the data detected by said at least three position sensors 2, 3, 4. Said central unit 9 also comprises a memory unit 90 configured to store the detected data, and / or a data transmission unit 91 configured to transmit the detected data to an external terminal 10, such as for example a personal computer or a smartphone.

Advantageously, the central unit 9 can also comprise an electric battery 92 for powering the central unit 9 itself, the sensors 2, 3, 4, and possibly also for powering the additional sensors or instruments of which the system 1 can be provided, such as, for example, the sensor 5 suitable for obtaining the heart rate and / or the oximetry saturation of the patient P, the chest belt 6, the abdominal belt 7, the sensor 8 for detecting the nasal airflow and / or oral and electroencephalograph.

In fact, as illustrated in figure 1, the central unit 9 can be contained in a box-like body 93 which can be fixed to the chest C of the patient P thanks to an elastic band 94, and therefore portable, from which the electrical connections for the various sensors and instruments depart. mentioned above.

Figure 2 schematically illustrates the arrangement of the sensors 2, 3, 4 respectively on the head H, on the neck N and on the chest C of the patient P. These position sensors 2, 3, 4 are connected by means of electrical connections 95 , to the central unit 9 of the system 1. If the system 1 also includes the vibrating devices 20, 30, 40, possibly integrated in the position sensors 2, 3, 4, these vibrating devices 20, 30, 40 are also they are connected, by means of electrical connections 96, to the central unit 9.

The aforementioned electrical connections 95 and 96 to the central unit 9 can be of the wired type or of the "wireless" type, such as wifi or bluetooth.

Advantageously, each of the at least three position sensors 2, 3, 4 is configured to detect the left / right rotation, the flexion / extension and the left / right inclination of the body segment H, N, C to which it is associated.

In fact, each of the three position sensors 2, 3, 4 can in turn comprise three single-axis position sensors or a single triaxial sensor.

Advantageously, the position sensors 2, 3, 4 can be accelerometers.

Advantageously, each of the three position sensors 2, 3, 4 is able to detect a plurality of intermediate positions between a maximum position and a minimum position, with respect to a reference axis.

For example, a left rotation of a body segment between 0 ° and 90 ° can be detected at intermediate values of 30 ° and 60 °. The same is true for right rotation, flexion, extension, left tilt, and right tilt measurements.

Advantageously, each of the three position sensors 2, 3, 4 is able to continuously detect the position assumed by a body segment, with respect to a reference axis, with an accuracy equal to or greater than -1 °.

In this way it is not only possible to discriminate for example with reference to the position of the chest C between a supine decubitus and a right or left lateral decubitus at 90 °, but it is possible to know exactly which intermediate position is taken by the patient, or even individually by one. more of the body segments monitored, between the extreme maximum and minimum positions.

The three tables illustrated in figures 3, 4 and 5 show all the positions detectable by system 1 of chest C, head H and neck N respectively.

The three rows of the tables of figures 3, 4 and 5 illustrate the possible positions assumed by the body segment and detectable by the relative position sensor, with reference respectively to the left / right rotation movement components (component A), flexion / extension (component B) and left / right inclination (component C) of the body segment.

For example, the first row of the table in figure 3 shows the positions of the thorax C detectable by the thoracic position sensor 4 with reference to the left / right rotation of the thorax C with respect to the longitudinal anatomical axis, that is, with respect to the axis passing through the head. feet. The second line shows the positions of the chest C detectable by the thoracic position sensor 4 with reference to the flexion / extension of the chest C with respect to the longitudinal anatomical axis. The third line shows the positions of the chest C detectable by the thoracic position sensor 4 with reference to the right / left lateral inclination of the chest C with respect to the longitudinal anatomical axis.

The table of figure 3 illustrates the various positions that the patient P can assume by varying the position of the chest C but keeping head H and neck N in the same position.

Similarly, the table of figure 4 illustrates the various positions that the patient P can assume by varying the position of the head H but keeping the chest C and neck N in the same position, obviously only where possible.

Similarly, the table of figure 5 illustrates the various positions that the patient P can assume by varying the position of the neck N but keeping the chest C and head H in the same position, obviously only where possible.

On the basis of the above it is therefore evident that the system 1 for the diagnosis of obstructive sleep apnea syndrome (OSAS), particularly of the type with a positional tendency, is able to detect all possible combinations of relative positions of chest C, head H and N neck of a patient P during sleep. Just to give an example, with a known type of polysomnograph, equipped only with a thoracic position sensor, the two positions assumed by patient P and illustrated in figures 6 and 7 would not have been distinguished and would have both been classified as a "patient in supine position ". Instead, as illustrated in the figures, head H and neck N can assume different relative positions with respect to chest C, more or less impacting the obstruction of the airways during sleep, and therefore more or less impacting both in terms of correctness of the diagnosis and subsequently. at the level of therapy efficiency.

The functioning of the system for the diagnosis of obstructive sleep apnea syndrome (OSAS), particularly of the type with a positional tendency, is clear and evident from what has been described.

In particular, the system can be used to conduct a nocturnal polysomnographic study integrated with the detection of the possible positions of the three body segments (head, neck and thorax) primarily involved in breathing in order to obtain diagnosis of OSAS, and in particular of P- OSAS, which takes into account the positions assumed by the patient in sleep.

With the system according to the invention it is therefore possible to identify the exact chest / neck / head position combinations associated with the genesis or aggravation of pathological obstructive apneas and hypopneas.

In practice it has been found that the system for the diagnosis of obstructive sleep apnea syndrome (OSAS), particularly of the type with a positional tendency, according to the present invention, achieves the intended aim and objects as it allows to improve the diagnosis of OSAS. , and in particular of the P-OSAS.

Another advantage of the system, according to the invention, consists in the fact that it can also be used to perform treatment therapies for OSAS, and in particular for P-OSAS, on the basis of the detected position data, through the emission of vibrations which dissuade the patient to maintain a position that aggravates the obstructive pathology.

A further advantage of the system, according to the invention, consists in the fact that it can be introduced in the nocturnal polysomnographic studies that are currently already being conducted, to improve its diagnostic efficiency. For this purpose, in fact, the system according to the invention lends itself to being integrated with existing polysomnographs, or with existing pulse oximeters, after suitable software and hardware preparation.

In particular, the system, according to the invention, can be used for carrying out type I, II, III and IV polysomnographic studies, depending on the vital parameters of the patient that it is decided to detect.

The system for diagnosing obstructive sleep apnea syndrome (OSAS), particularly of the type with a positional tendency, thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept.

In practice, the materials employed, so long as they are compatible with the specific use, as well as the contingent shapes and dimensions, may be any according to requirements.

Claims (10)

CLAIMS 1) System (1) for the diagnosis of obstructive sleep apnea syndrome (OSAS), particularly of the type with positional tendency, characterized by the fact of including at least three position sensors (2, 3, 4) applicable respectively to the following three segments body (H, N, C) of a patient (P): head (H), neck (N) and thorax (C), called at least three position sensors (2, 3, 4) being able to detect the position of said three body segments (H, N, C) during the sleep of said patient (P). 2) System (1), according to claim 1, characterized in that it comprises at least one sensor (5) suitable for obtaining the heart rate and / or oximetry saturation of said patient (P) during sleep. 3) System (1), according to claim 1 or 2, characterized in that it comprises at least one vibrating device (20, 30, 40) applicable to at least one of said three body segments (H, N, C), said at least one vibrator device (20, 30, 40) being activated according to the position of at least one of said three body segments (H, N, C) detected by one or more of said at least three position sensors (2, 3, 4) during the sleep of said patient (P). 4) System (1), according to one or more of the preceding claims, characterized in that it comprises a thoracic belt (6) suitable for detecting the thoracic expansion of said patient (P) and an abdominal belt (7) suitable for detecting the abdominal expansion of said patient (P). 5) System (1), according to one or more of the preceding claims, characterized in that it comprises a sensor (8) for detecting the nasal and / or oral airflow of said patient (P). 6) System (1), according to one or more of the preceding claims, characterized in that it comprises an electroencephalograph suitable for detecting the brain electrical trace of said patient (P). 7) System (1), according to one or more of the preceding claims, characterized in that each of said at least three position sensors (2, 3, 4) is configured to detect left / right rotation, flexion / extension and left / right inclination of the body segment (H, N, C) to which it is associated. 8) System (1), according to one or more of the preceding claims, characterized in that each of said at least three position sensors (2, 3, 4) comprises at least one accelerometer. 9) System (1), according to one or more of the preceding claims, characterized in that it comprises a central unit (9) configured to receive the data detected by said at least three position sensors (2, 3, 4), said central unit (9) comprising a memory unit (90) configured to store said data, and / or a data transmission unit (91) configured to transmit said data to an external terminal (10). 10) System (1), according to one or more of the preceding claims, characterized in that each of said at least three position sensors (2, 3, 4) is able to detect a plurality of intermediate positions between a maximum position and a position minimum, with respect to a reference axis.