RU2440024C2 - Method of testing human brain response to hypoxia - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention is related to physiology and medicine. Electroencephalography (EEG) is preceded by measuring alpha band and beta band wave amplitude in quiet breathing and in breath holding. The brain response to hypoxia is measured by formula: RH=(EEG₂ - EEG₁)/EEG₁*100, where RH is the response to hypoxia, %, EEG₁ is the wave amplitude in quiet breathing, mkV, EEG₂ is the wave amplitude in breath holding, mkV, 100 is a data conversion constant, %.

EFFECT: method extends the range of products for testing the brain response to hypoxia.

1 tbl

Description

The invention relates to physiology and medicine, in particular to functional diagnostics, and can be used to assess the general condition of a person under normal and pathological conditions.

The reaction to hypoxia is due to the large dependence of the brain on oxygen delivery. It is known that in an adult, to maintain normal life, the brain uses up to 20% of the oxygen consumed by the body [1]. Delayed oxygen delivery (hypoxia) is accompanied by a reaction of the brain in the form of changes in its electrical activity, recorded using electroencephalography.

A known method of studying the reaction of the human brain to hypoxia by electroencephalography [2].

In accordance with a known method, the state of an EEG of a human operator is studied in acute hypoxia. The disadvantage of this method is that it uses a situation in which a person undergoes psychological stress during the work shift, which can lead to the development of an acute lack of oxygen, which makes hypoxia pathological.

There is also a method of studying the reaction of the human brain to hypoxia by electroencephalography [3].

In accordance with the known method, the subject breathes for 15 minutes through a special mask with a gas mixture with an oxygen content of 8%.

The disadvantage of this method is that it uses a pre-prepared gas mixture with 8% oxygen content, the mask method and the EEG recording time of up to 15 minutes

The proposed method for studying the reaction of the human brain to hypoxia is characterized in that the subject holds his breath on inhalation for a time convenient for him, which lasts for an adult without special training within 2 minutes. This time is 7 times shorter than by the method [3] and hundreds of times shorter than by the method [2]. There is no need to prepare a gas mixture, a clinical condition does not occur, because the subject himself controls the length of breath holding convenient for him. EEG recording is carried out with calm breathing of the subject and during breath holding.

The reaction of the human brain to hypoxia in accordance with the proposed method is determined by the formula.

The proposed method is implemented as follows. After preliminary hyperventilation (three maximum breaths and exhalations), the subject is asked to determine the time during which he is able to hold his breath on inhalation. Then begins the EEG recording, during which the subject breathes calmly, and then holds his breath for maximum breath. The study of the reaction of the human brain to hypoxia is carried out according to the formula:

RG = (EEG ₂ -EEG ₁ ) / EEG ₁ * 100,

where RG is the reaction to hypoxia,%,

EEG ₁ - the amplitude of the waves with calm breathing, μV,

EEG ₂ - the amplitude of the waves during breath holding, μV,

100 - coefficient for data conversion,%.

The results protocol is shown in the table.

The test
being Age,
years Body mass,
kg Height,
cm Delay
source
from The amplitude of the waves in the alpha range, μV The amplitude of the waves in the beta range, μV Background Delay Change-
% Background Delay % Changes TO 22 45 152 65 94 39 58.5 41 72 43.1 L 22 59 176 45 84 56 33.3 39 61 36.1 Ts 23 54 168 55 87 45 48.3 38 66 42,4

As can be seen from the table, the individual reaction of the brain to hypoxia in terms of EEG differs in the subjects by 1.5-2 times. At the same time, breath holding on inspiration leads, as can be seen from the protocol (table), to a decrease of 33-58% of the wave amplitudes in the alpha range and to an increase of 36-43% of waves in the beta range.

Information sources

1. Human physiology. Under. ed. G.I.Kositsky. M .: Medicine. 1985.420 s.

2. Shekhovtsev I.K., Shpatenko V.M., Timofeeva T.V. Change in the electroencephalogram of a human operator in acute hypoxia // Nur. Med. J. 1997. v.5, N1, p. 11-13.

3. Brown E.A. The relationship of changes in local and spatio-temporal spectral characteristics of EEG under hypoxic exposure in humans // Ros. fiziol. g. 2005.V. 91. No. 11, p. 1260-1279.

Claims (1)

A method for studying the reaction of the human brain to hypoxia by electroencephalography (EEG), characterized in that the amplitude of the alpha or beta waves of the EEG is measured first with calm breathing and breath holding on inspiration, and the brain response to hypoxia is studied by the formula:
RG = (EEG ₂ -EEG ₁ ) / EEG ₁ · 100,
where RG is the reaction to hypoxia,%;
EEG ₁ - wave amplitude with calm breathing, μV;
EEG ₂ - the amplitude of the waves when holding the breath, µV;
100 - coefficient for data conversion,%.