The method of determining the functional capacity of the cardiorespiratory regulation system
The invention relates to medicine. Record the heart rhythm on the ECG. Record the velocity of capillary blood flow of the finger. Register the speed of the air flow during breathing. Eat the above parameters is carried out in three stages: at rest, at a given rate of breathing, equal to 6 breaths per minute, while samples with a maximum delay of breath on the inhale and the exhale, or when the sample of Valsalva. The obtained parameter values of all measurements analyzed with obtaining time series of these indicators. Determine the degree of mutual correlation of these series. On the obtained cross-correlation coefficients calculate the degree of synchronization parameters of cardiac activity and respiration. The method allows to diagnose premorbid States, prior to development of diseases of the cardiovascular and respiratory systems. 3 Il., 4 table.
The invention relates to the field of applied physiology, preventive and rehabilitation medicine, in particular to methods of early diagnostics of premorbid conditions prior to the development of diseases of the cardiovascular and respiratory system.
Known SPO is a graphical curve recorded during exhalation (SU, A. S. No. 1833714, class. And 61 In 5/08 from 04.03.1991).
Thus cardiorespiratory reserve is determined by the ratio videoholica air volume and total lung capacity at the time of registration the maximum stroke volume. The reserve is higher, the higher the amount of videoholica air.
However, this method evaluate essentially the spare capacity of the respiratory system as one of the parts of the mechanism cardiorespiratory regulation and it is impossible to assess the reserves of the cardiovascular system.
Also there is a method of assessing the functional state of regulatory systems of the organism biological object in heart rhythm, allowing on the basis of histographical and spectral analysis of time series of ECG to determine the degree of tension of regulatory systems of the body and be divided into four main functional status (normal, psycho-physiological status, premorbid status, pathological condition), (RU, patent No. 2103911, class. And 61 In 5/04 from 10.02.1998).
However, the judgment about the functional reserves of the body is held indirectly by the degree of tension of regulatory systems (the higher it is, the less functional reserves).
In addition, the assessment of functional status is not taken into account the role of the respiratory system is ATM, the known method does not allow a sufficiently reliable to determine the functional reserves of the regulation of the cardiovascular and respiratory systems.
The closest technical solution is a way of Express-analysis of cardiac rhythm, including registration of ECG, which build a histogram of RR-intervals, determining the maximum and minimum duration of the R-interval, their difference, fashion histogram, registration pulsogram (RU, patent No. 2077864, class. And 61 In 5/04, 5/0402 from 27.04.1997).
However, in the known method for obtaining pulsogram use only ECG signals and the doctor analyzes only the data time series of RR-intervals. With fingers record the electrocardiogram, which is used to build the series of RR-intervals, and for this recording can not be concluded pulse blood filling of the finger (the state of the vessels of the finger).
In addition, registration of ECG and measurement of RR-intervals is produced at rest without any stress tests.
All this is not enough for judgments about the functional reserves of the cardiac activity and cardiorespiratory reserve, including the joint activity of the heart, blood vessels and respiratory system.
Task iteka, consequently there is a possibility of judgments about the functional reserves of the organism and timely actions required to ensure normal functioning of the body.
This is achieved by a method for determining the functional reserves of the cardiorespiratory system by recording heart rhythm ECG registration and velocity of capillary blood flow of the thumb, at the same time register the speed of the air flow during breathing, the obtained parameter values of all measurements analyzed with obtaining time series of these indicators - the duration of the R-interval, pulse wave velocity, the duration of the respiratory cycle, determine the degree of mutual correlation of these series and the computed cross-correlation coefficients calculate the degree of synchronization parameters of cardiac activity and respiration and module average correlation coefficient, and eat the above parameters is carried out in three stages, the first of which is at rest on the second stage at a given rate of breathing, equal to 6 breaths per minute, and the third is when samples with a maximum delay of breath on the inhale and the exhale, or when the sample of Valsalva (deep VD is then and compare their values at rest and functional respiratory tests and dynamic series of these metrics compute the power spectrum in the ranges breathing of 0.4 to 0.15 Hz and vasomotor of 0.15 to 0.04 Hz waves and compare their values at rest and during the sample with a fixed rate of breathing 6 breaths per minute, and with the breath on the inhale and exhale.
To accomplish the task, use the monitor complex diagnostic equipment for studies of reactions of the cardiovascular and respiratory systems, comprising a housing container, inside of which is placed a block of reception and processing of information, providing registration of the electrocardiogram, be noticed, and for additional registration pneumotachography it is equipped with standard headband installed on the last under the nose of the subject operator on the flexible holder of the microphone capsule, which is made with a meter air flow rate in the form of a thermistor element connected to the unit receiving and processing information, and a unit for receiving and processing information supplied connectors, located in its upper end portion for connection of sensors and electrodes placed in wear on the belt of the subject operator housing container having posted his side of the connector to the computer.
In addition, the monitor complex diagnostic equipment for studies of reactions of the cardiovascular and respiratory systems unit receiving and processing information may include internal memory.
the reaction of the cardiovascular and respiratory systems of the human operator; in Fig.2 is an external view of a standard headband with microphone capsule, which houses thermistor capnography the respiration sensor of Fig.3 is a block diagram for implementing the method.
The scheme includes a housing container 1, worn on the belt of the subject operator. Wearable device-the container is responsible for receiving and processing information of three biological parameters (electrocardiogram, sphygmogram and pneumotachograph) and save them in memory or transferred to the computer 2 for further processing and analysis, and also contains special software that implements the original algorithm, which allows to study the interaction of regulatory mechanisms of respiration and circulation while performing a series of special functional tests. thermistor element 3 to register pneumotachography, sphygmography sensor 4, a single adhesive ECG electrodes 5 are placed on the body so that it does not interfere with the professional activities of the operator. Standard headband 6 has a flexible holder 7 with the microphone capsule 8, in which is placed a meter air flow rate in the form of a thermistor element 3 connected through the plug 9 with a container 1. The last and in the side of the connector (on the drawing is not specified) to the computer 2. The bands 10, 11, 12 serve to secure the cables of the sensors 4 and thermistor element 3.
The proposed method is as follows. Registration signals produced initially at rest at the position of the subject should be sitting for 10 minutes, then the screen display set the pace of breathing 12 breaths per minute and 6 breaths per minute (each mode for 3 minutes); then start the breath on the inhale, which continue as long as possible, the same test carried out on the exhale.
The recordings in digital form remain in the computer's memory (or internal memory) unit for receiving and processing information, and after the end of the study (or studies) are automatically analyzed by the detection of characteristic points on the curves and the calculation of the following key indicators:
1) the duration of RR intervals,
2) the velocity of propagation of pulse wave (from the top of the R-wave of the ECG before lifting anekdoty SFG (R-a)
3) the duration of the respiratory cycle (eEx-In).
These figures are calculated in each cardiac cycle. On the obtained values of the indicators form 3 dynamic range of numerical values, then for each set of values calculate the standard is AI) and compute the cross-correlation coefficients between the values of 3 series performance. Based on these factors determine the structure of the functional system of the heart-vascular-light".
Three of the correlation coefficient to determine the interaction (vzaimodeistvie) regulatory mechanisms, and their average value (modulo) indicates the current functional state of the cardio-respiratory system. You may be given a differential assessment of each of the components of the regulatory mechanism and, thus, identified the weakest link, which is important for predicting functional status and development of preventive measures.
Changes of the coefficients of correlation between the different indicators in the experiment with long-term isolation (test K.).
Table 1 shows data obtained from one of in the experiment with long-term isolation. Here are the modules of the cross-correlation coefficients for each of the components of the regulatory mechanism, and the average correlation coefficients at different stages of the experiment. You can see that the increase in the average correlation coefficient, which corresponds to the development of the condition expressed functional tense in this system there is no voltage, either due to its high resistance to factors, or because the voltage in other systems compensates for the preservation of the most important for an organism of the relationship between vascular tone and respiratory cycle.
Along with the cross-correlation time series indicators calculate the coefficients of variation for each series. As you know, the work of regulatory mechanisms is manifested in the "features of variation", i.e. the more active the process of regulation, the higher the coefficient of variation of the studied parameters.
Changes of coefficients of variation of various parameters in the experiment with long-term isolation (test K.).
Table 2 shows the coefficients of variation of the three parameters in the experiment with long-term isolation. From these data it is seen that on the 1st month of the experiment the activity of regulatory mechanisms is growing, which is explained by the necessity of readjustment of the organism to new conditions in a limited volume (in isolation). Moreover, the coefficient of variation of the breathing cycle is not changed, that confirms compensatory changes in other systems aimed at maintaining stability in the respiratory si the regulatory mechanisms, to reduce their activity. The most stressful part is the regulation of vascular tone (lower coefficient of variation of the indicator pulse wave velocity). The least stressful part is the respiratory system in which there is the least degree of reduction of the coefficient of variation.
The proposed method provides for functional load tests with different modes of breathing, which aimed to assess the functional reserves of the regulatory mechanism.
Changes of coefficients of variation of different parameters during functional load tests (test Century).
Table 3 presents the changes of coefficients of variation (activity of regulatory systems in different functional tests. At a fixed rate of breathing stimulates the activity of parasympathetic regulation, which leads to an increase related to breathing variations in the duration of the R-interval. This variability indices of pulse wave velocity increases to a lesser extent, because vascular tone is regulated through the sympathetic division of the autonomic nervous system. Noknot indicators of vascular tone decreases to a greater extent than the variability of the R-interval.
A good indicator of the activity of the parasympathetic regulation during tests with a fixed rate of breathing are indicators of spectral analysis. The higher the functional reserves of the regulation, the greater the power of the harmonic components of the spectrum at a frequency with a period of 10 s (see table 4). Especially clearly these reactions occur in the analysis of heart rhythm.
Changes in the power spectrum of heart rate variability in the range of 0.15 to 0.04 Hz (period 7-25 C) when conducting functional load tests with a fixed rate of respiration (test Century).
According to the results of spectral analysis calculates the ratio of the average power of vasomotor waves to the average power of the respiratory waves (LFav/HFav). This indicator characterizes the autonomic balance, and what its value is greater, the greater the predominance of sympathetic regulation over the parasympathetic. The example shows that when the delays are clearly marked sympathetic activation. At a fixed rate of breathing at 6 breaths per minute (slow breathing) the appearance in the spectrum of slow waves with this artificially imposed kitomo reflects the degree of activation of the parasympathetic division, backup capabilities parasympathetic regulation.
The proposed method is carried out by bringing a subject person of functional tests with different modes of breathing and in the analysis of the obtained metrics calculation
a) coefficients of cross-correlation time series;
b) coefficients of variation for each dynamic range;
C) power spectrum of heart rate variability in the ranges of the respiratory and vasomotor waves (HF and LF).
The initial functional state of the organism is determined by the cross-correlation coefficients. When this average value is usually in the range of 0.4 to 0.7. The most stable element of regulation is determined by the lowest correlation coefficient. The most stressful element of regulation is determined by the highest correlation coefficient.
Functional reserves of the mechanism of regulation of the cardio-respiratory system is determined by the reaction on the required functional tests with different mode of breathing. When this functional reserve is higher, the more actively included some sections of the regulatory mechanism in the process of adapting to a new mode of breathing. At a fixed rate of breathing is actually the major-R-interval, pulse wave velocity and power spectrum of heart rhythm. The greater the increase in these parameters in response to the requirements of the impact, the higher the functional reserves of the parasympathetic division of the autonomic nervous system.
When breath tested mainly sympathetic division of the autonomic nervous system. Reserves of sympathetic regulation of the higher, the stronger when this is expressed in the reduction of heart rate variability and indicators of vascular tone and the higher LFav/HFav.
Thus, the proposed method allows to estimate the functional reserves of the mechanism of regulation of the cardio-respiratory system of a person and early to identify possible deficiencies in health status.
Complex monitor diagnostic equipment that implements the specified method is a placed on the belt of the subject miniature body-size container HH mm with connectors for connecting the electrodes and sensors are installed in the upper front part of the building that creates convenience for fixing and increases the immunity, the cable connection to the computer is located in the lower front part of the building, and also the possible operation of the unit without regard to the backgrounds and microphone where to place a microphone installed thermistor changes its resistance depending on the changes in the speed of the air flow during inhalation and exhalation.
Thus, the complex that implements the method of determining the functional reserves of the cardiorespiratory system, can be used in surveys of persons at the workplace at different stages of their activities, including conducting research in space flight.
The method of determination of the functional reserves of the cardiorespiratory system, including registration of heart rate on ECG and the recording speed of capillary blood flow of the finger, wherein simultaneously register pneumotachograph, all parameters recorded in three stages: at rest, at a given rate of breathing, equal to 6 breaths per minute, while samples with a maximum delay of breath on the inhale and the exhale or Valsalva's test, all of these parameters are analyzed to obtain time series of indicators that determine the degree of mutual correlation of these series, and the correlation coefficient is normally 0.4 to 0.7, the most robust level of regulate is given by the highest correlation coefficient, calculate gain coefficients of variation of the duration of the R-interval, pulse wave velocity and power spectrum of heart rhythm at a fixed rate of breathing, while the functional reserves of the parasympathetic division of the ANS is the higher, the greater the gain coefficients of variation of the duration of the R-interval, pulse wave velocity and power spectrum of heart rate, sampling breath reveal the reserves sympathetic, dynamic series of these metrics compute the power spectrum in the ranges breathing of 0.4 to 0.15 Hz and vasomotor of 0.15 to 0.04 Hz waves, the higher the functional reserves of the regulation, the greater the power of the harmonic components at a frequency with a period of 10 s (0.1 Hz) in comparison with its power alone, calculate the ratio of the power of vasomotor waves to the average power of the respiratory waves when conducting functional load tests with a fixed rate of breathing, the value of which is greater, the greater the predominance of sympathetic regulation over the parasympathetic.
SUBSTANCE: method involves measuring cardio- and hemodynamic values, calculating estimates of the values and displaying the estimates on monitor. Measuring and calculating each cardio- and hemodynamic value is carried out during basic periods of their oscillations corresponding to heart contraction cycle and respiratory cycle related to absolute time.
EFFECT: high accuracy of estimation.
4 dwg, 1 tbl