DE102010056478A1 - Apparatus for complex long-term monitoring of human autonomic regulation during sleep or falling asleep relaxation phases, has breathing mask comprising forehead pad with sensor unit to non-invasively register vegetative parameters - Google Patents

Abstract

The apparatus collects and analyzes the systemic coordination of interaction between heart and respiratory rates. A nasal mask (NM) produces breathing air over pressure-generation. A forehead pad (SP) of mask is integrated with sensor unit for non-invasive registration of the vegetative parameters such as heart rate, respiratory rate, oxygen saturation and dermal head movement in the forehead skin. An independent claim is included for device for complex long-term monitoring of human autonomic regulation during sleep or falling asleep relaxation phases.

Description

The invention relates to a respiration device with integrated sensors for the noninvasive detection of dermal perfusion dynamics of humans according to the preamble of patent claim 1.

For many years ventilation devices have been known which are used for the therapy of various symptoms of the so-called sleep apnea syndrome (SAS, respiratory arrest of about 10 seconds to a few minutes during sleep). The respiratory arrest leads to an insufficient supply of oxygen to all body organs, including the skin, and thus via a vegetative control of the body to accelerate the pulse and other wake-up reactions. The result of wake-up reactions is a non-restorative sleep; untreated SAS can cause other chronic health problems (high blood pressure, heart attacks and others).

The respiratory therapy devices according to the prior art usually consist of a mask to be applied to the nose, which is connected via a hose to a device with a fan. With this device, a permanent air pressure of about 5 to 20 millibars is generated during sleep in the airways. The cardiac activity does not affect the known ventilators, although this, as already explained, is very sensitive to the diminished oxygenation of the body. This disadvantage is to be eliminated according to the teaching of this invention. For this purpose, an optoelectronic sensor (Optrode) is inventively integrated into the respiratory mask, with the help of which the most important vital parameters such as heart rate, oxygen saturation of the skin and the respiratory rate can be monitored in a non-invasive way and completely unburdening for the patient. In its minimal configuration, the Optrode consists of two selective light sources (LEDs) with different wavelengths and a photodetector, which detects the backscattered by the dermal vessels light components.

Since the 1930s at the latest, it has been known that the dynamics of blood volume fluctuations in close-up vascular networks on the human body are subject to strong individual variations even under physiological conditions in their course and frequency-selective composition.

In recent decades, a whole range of devices for noninvasive optoelectronic detection of dermal hemodynamics has been developed. Devices which are assumed in the formulation of the preamble of claim 1 are, for example, from the patents DE 3100610.8 (Blazek and Wienert, 1981), DE 3609075.1 (Schmitt and Blazek, 1986) and DE 4226973.3 (Blazek and Schmitt, 1992). All of these devices have an optoelectronic sensor that includes at least one light source and a light detector. Incidentally, these documents are expressly referenced to explain all not described here in detail.

Most of these devices are methodically based on that of AB Hertzman in "The blood supply of various skin areas as estimated by the photoelectric plethysmograph" (Amer. J. Physiol., 124 (1938) ) first described principle of photoplethysmography (PPG short).

The PPG technique is based on the fact that the light in the near infrared range and much of the visible of hemoglobin or blood is absorbed much more than tissue. Since a vascular dilatation is always associated with an increase in the blood volume in the measurement scenario, inevitably increases the absorption volume. If selective light of low intensity is then transmitted into the tissue, a detector in the vicinity of the light coupling will receive less light as the blood volume in the measurement area increases. It is also known that the photoplethysmographic signals generally consist of a relatively large nonpulsatile signal component (d.c., d.c. signal) which is superposed by an amplitude-wise much smaller perfusion signal (a.c., alternating signal), which in turn is composed of different frequency components. Finally, optoelectronic sensors are known which use several wavelengths in the red and infrared regions of the spectrum, for example for determining dermal oxygen saturation (pulse oximetry).

The main object of the invention is to implement the above written for the first time in the form of a simple and inexpensive realizable respiratory mask, the signals of the integrated Optrode can be used to monitor the respiratory autonomic regulation of the body and the systemic interaction between the respiratory and heart rate. This can in turn be used z. For example, to optimize the ventilation regimen during sleep or to help you fall asleep.

An inventive solution to this problem is characterized in claim 1. Further developments of the invention are the subject of the following claims.

The invention will now be described by way of example without limitation of the general inventive concept using exemplary embodiments with reference to the drawings, to which reference is expressly made, moreover, with respect to the disclosure of all details of the invention not explained in detail in the text.

Show it:

1 the basic structure of the device in which the Optrode has been integrated in the forehead pad of the respiratory mask;

2 the basic structure of the Optrode;

3 and 4 one of the possible embodiment of the device, photographed from two viewing directions;

5a typical signal at the output of the Optrode (dermal perfusion change as a function of time)

5b Presentation of the individual skin perfusion rhythm 4a in the frequency domain after a Fourier transform.

1 1 schematically shows an exemplary embodiment of the measuring arrangement according to the invention and also indicates the application of the "intelligent" nasal mask (NM) to the patient's face (P) in its preferred application in the context of medical sleep disorder diagnosis and therapy. The Optrode ( 1 ) is installed in the forehead pad (SP) of the mask and is connected via an electrical cable connection ( 2 ) with the preferably in the ventilator (BG) integrated evaluation ( 3 ) connected; the sensor signals (vital parameter characteristics) evaluated here are, according to the teachings of the invention, used for the first time to control the ventilator continuously or with a time-selective effect. With a flexible hose (LA), the mask is airtight connected to the ventilator.

A preferred embodiment of the Optrode ( 1 ) shows 2 , It contains two LEDs ( 1a . 1b ) with different wavelengths and a photodetector ( 1c ), whereby these components by optical barriers ( 1e and 1f ) are spatially separated from each other so that direct reflections on the skin surface (HO) and thus interference signal coupling can be suppressed. For example, the Optrode can be coated with a double-sided, light-transparent film ( 1g ) on the inside of the likewise transparent wall ( 1h ) of the support pad of the mask and works in this case in the reflection mode and is square or rotationally symmetrical and also includes a motion sensor ( 1d ) for detecting the head movements whose signal can be used to detect the movement artifacts. To minimize the number of electrical conductors in the cable connection ( 2 ), the Optrode can also contain necessary electronic circuits in highly integrated form.

3 and 4 show one of the possible embodiments of the "intelligent" nasal mask from two different viewing directions and attached to a head phantom.

The curves in 5 , clearly show a typical perfusion signal in the forehead, shown in the time and frequency domain. There are various cardiac and respiratory coupled perfusion rhythms, but also slower rhythms independent of these central oscillators of the body. Also indicated in the figure is a period of about 5.5 seconds during which 5 heart periods and 1 respiratory period were registered, corresponding to a heart rate of 1.05 Hz and a respiration rate of 0.21 Hz. This corresponds to the physiological, systemic interaction between heartbeat and respiration (coupling 1: 5). By correspondingly synchronous regulation of the air overpressure in the respiratory passages with, for example, one fifth of the heart rate, optimized operations for falling asleep for the mask wearer can be created for the first time. In addition, the "two-wavelength measurement principle" of the Optrode allows a transcutaneous determination of the oxygen saturation in the blood during the entire wearing time of the mask.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 3100610 [0005]
• DE 3609075 [0005]
• DE 4226973 [0005]

Cited non-patent literature

• AB Hertzman in "The blood supply of various skin areas as estimated by the photoelectric plethysmograph" (Amer. J. Physiol., 124 (1938) [0006]

Claims (7)

Apparatus and method for the complex long-term monitoring of the human autonomic regulation during sleep or dormant relaxation phases and for the detection and analysis of the systemic coordination interaction between the cardiac and respiratory rate, consisting of a respiratory mask and an overpressure in the respiratory tract, characterized in that in the forehead pad Mask a sensor unit for noninvasive registration of the vegetative parameters in the area of the forehead skin is integrated (heart frequency, respiration frequency, dermal oxygen saturation and head movement). Apparatus according to claim 1, characterized in that the signals of the sensor unit for controlling the air pressure in the pneumatic system of the device and the respiratory passages are used. Apparatus according to claim 1 or 2, characterized in that the sensor unit is designed as an optoelectrode with at least two light sources and a light detector, wherein the light sources emit light of different measuring wavelengths. Device according to one of claims 1 to 3, characterized in that the sensor unit additionally includes a motion sensor whose signal is used for detection and pattern recognition of the head movement. Device according to one of claims 1 to 4, characterized in that the optrode is integrated into the respiratory mask such that only a slight and reproducible contact pressure is exerted on the scalp and the skin perfusion is not hindered. Device according to one of claims 1 to 5, characterized in that the control and evaluation unit monitors the working regime of the Optrode, the measurement signals independently analyzed and correlated with each other. Device according to one of claims 1 to 6, characterized in that as light sources selected light emitting diodes (LEDs) or laser diodes (LD's) are used, which selectively point and focus or diffuse and illuminate the selected area of tissue over a large area.

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