oxygen saturation level. What is saturation and pulsometry, the essence of the methods, the norm and deviations. What is a sensor

The main indicator of the healthy functioning of the organs and systems of the body is the amount by which the arterial blood composition is saturated with oxygen molecules.

This index is reflected in the number of erythrocyte molecules and can be determined using the measurement technique of pulse oximetry.

What is naturation?

At the initial stage, the air inhaled by a person enters the lungs, where there is a powerful network of capillaries, which absorbs oxygen from the air, which is necessary for the operation of all systems and organs, as well as for the process of metabolism in the body, and the synthesis of molecules and substances in the body.

In order for oxygen ions to be delivered to the place of its consumption, erythrocyte molecules are provided for these purposes in the body, which are filled with molecules of red pigment (hemoglobin), which serves as an oxygen transporter throughout all cells of the body.

One molecule of red pigment (hemoglobin) in the composition of an erythrocyte is able to take 4 oxygen molecules “on board” with it.

The process of saturation of hemoglobin molecules in the composition of red blood cells, which are contained in the blood, is called the process of saturation.

If hemoglobin uses all its reserves in work and gains 4 oxygen molecules for each of its molecules, then the saturation is 100.0% in ensuring the vital activity of organ cells and in the efficiency of erythrocyte molecules.

For the normal functioning of all organs and cells of systems, it is enough to have a saturation level of 95.0% or more.

In medicine, saturation assesses the condition of the patient under the influence of anesthesia during the period of surgical intervention on the body.

When oxygen in the blood is normal, a person feels healthy, but if the saturation index begins to fall, then this is a clear sign of the development of a pathological disease in the body. It is necessary to immediately make a diagnosis of the body to detect pathology.

A sharp decrease in saturation occurs with diseases of the respiratory system and diseases of the bronchi and lungs.

The method of controlling oxygen in the blood - pulse oximetry

It is necessary to constantly monitor blood saturation, especially for people who suffer from pathologies of the blood flow system and the hematopoietic system. To control saturation, a device for measuring saturation was invented - a pulse oximeter.

The principle of operation of this pulse oximeter device is developed on the basis of differentiated light absorption by hemoglobin molecules and a light wave is obtained during measurement, which determines the saturation of hemoglobin with oxygen molecules.

The pulse oximeter device is based on the action of two wavelengths:

Wave length 660.0 nm - called the red wave;
The wavelength of 940.0 nm is called the infrared wave.

Algorithm for performing pulse oximetry

The pulse oximeter also contains a processor with a monitor and a photodetector, which:

Information is taken using a peripheral sensor having 2 waves for reading saturation information;
The degree of absorption of red and infrared waves comes from the level of saturation in the blood;
A stream of light that is not claimed by blood takes over the photodetector;
The data is transferred to the processor, it processes it, translates it into the required percentages and submits it to the monitor screen.

With the method of pulse oximetry, the saturation of the blood composition is determined no longer than 20 seconds after the procedure.

Types of pulse oximeter

The pulse oximeter determines the arterial component at the volume of blood during the pulse.

This pulse oximetry procedure has 2 types of work:

Transmission type of saturation determination;
Type of reflected saturation.

In the transmission type of analysis, a wave of light is used that passes through the tissues of the body.

The sensors that emit the wave and the sensors that receive the light wave flow are arranged parallel to one another. The meter for research and the photodetector is located on the finger, and you can also place them on the ear, or the wing of the nasal sinus.

With the reflected type of saturation determination, the sensors for receiving and emitting a wave are located side by side.

A device that is based on the working principle of reflection, can remove information on the saturation of the blood with oxygen from various parts of the body:

From the front;
On the stomach;
On the upper limb in the region of the forearm;
On the lower limb from the lower leg.

The coefficients of the two types of measurement of saturation with pulse oximetry are almost the same.

In clinics, stationary pulse oximeters are used, and at home, portable devices can be used, which are:

Determining readings using a device that is worn on the finger;
Oxypulsometer for children - can be used to determine the oxygen saturation of the blood in newborns;
Wrist pulse oximeter.

Before using a portable type of pulse oximeter, the instructions for use must be studied.

How to use a pulse oximeter at home?

After the instructions have been carefully studied, it is possible to measure the saturation and determine what saturation of the blood with oxygen molecules:

Oximetry in adults (measuring the oxygen content in the blood) is carried out in a poorly lit room;
When measuring saturation, a person should not be nervous;
The device must be fully charged, if it is powered by the mains, then plugged into the outlet;
Put the sensor of the device on a certain place, which is indicated in the instructions for use for a specific model of the heart rate monitor;
The result of pulse oximetry is determined and displayed on the display in a few seconds;
To measure at home, the patient must know how much oxygen should be in the blood. If the device shows too low an index, it is recommended to have a pulse oximetry test in the clinic in order to know your specific saturation values.

Indications for measurement of saturation by the method of pulse oximetry

An instrumental analysis is prescribed to check the saturation of the blood composition with oxygen molecules in the following conditions of the body and pathologies:

With insufficiency of the respiratory system and its organs, regardless of its etiology;
In the treatment of oxygen therapy;
During surgical interventions in the body;
During the rehabilitation period after vascular surgery;
With pathology of the blood circulation system;
During the treatment of diseases that are associated with the integrity of blood vessels;
With genetic hereditary pathologies of the hemostasis system;
With congenital pathology of the destruction of erythrocyte molecules;
With anemia of various etiologies;
With the development of sleep apnea;
With hypoxia of internal vital organs;
With hypoxia of brain cells;
In chronic pathology, hypoxemia.

Measurement of saturation by the method of pulse oximetry

Sometimes it is necessary to use pulse oximetry at night in order to measure the level of saturation during this time period. A person during sleep may develop sleep apnea, or other pathologies in which there is a possibility of a complete cessation of breathing.

This condition is very dangerous not only for the human body, but also for the life of the patient. Quite often, such pathologies cause death during sleep.

Sleep apnea attacks, in which breathing stops, can develop with the following pathologies in the body:

Obesity;
Diseases of the heart organ;
Insufficiency of the cardiac type;
Disease of the circulatory system;
In violation of the blood supply to brain cells, blood;
In case of failure in the endocrine system;
Thyroid diseases;
Pathology of myxedema;
With arterial hypertension;
Diseases of the lungs.

Such a violation of breathing during sleep may indicate oxygen starvation of organs at a time when a person is sleeping. Due to this oxygen starvation, apnea develops, which prevents a person from sleeping normally.

People who snore at the time of sleep complain of such symptoms after a night's rest:

To determine whether there is really a decrease in the oxygen content in the blood during sleep apnea, the measurement of saturation by the device with a pulse oximeter will help.

Computer type pulse oximetry, which is carried out at night, takes a long time period, in which saturation is constantly monitored. In addition to saturation, this type of pulse oximetry checks and controls the pulse of a sleeping person, the nature and type of the pulse wave.

The pulse oximeter device determines blood oxygen saturation more than 30.0 thousand times during the entire night's sleep period.

Computer pulse oximetry can also be used at home, it does not have to be in a hospital ward. In stationary conditions, pulse oximetry is performed only if the patient's condition is such that he needs to be treated in the clinic's hospital.

The algorithm of pulse oximetry operation during the patient's sleep:

The sensor of the device is worn on the wrist, or on the finger of one hand. With the computer type of pulse oximetry, the device turns on automatically and also automatically records all the information for the studied period of time;
The heart rate monitor must be on the arm throughout the entire period of time, it cannot be removed. Every time the patient wakes up from the sleep state, the pulse oximeter sensor detects this state;
The device is removed from the hand only in the morning, and the results of the study are studied by the attending doctor.

The patient undergoing pulse oximetry should go to bed in conditions that are conducive to comfortable sleep:

The temperature in the bedroom should be at least 20 degrees Celsius, and the maximum should not exceed 23 degrees;
Do not take sleeping pills before going to bed;
On the eve of sleep, do not take sedative drugs;
At night, do not drink tea, as well as caffeinated drinks;
Do not overeat for dinner and exclude fatty foods from the dinner menu.

If normal indicators are fixed, then it is necessary to look for the etiology of apnea, but if the saturation during night sleep decreases below 88.0%, then we can talk about oxygen starvation at night.

For recovery, it is necessary to carry out oxygenation at night in a sick person.

How to prepare the body for a study using pulse oximetry?

The method of pulse oximetry is safe and is used even during pregnancy and during breastfeeding. A pulse oximeter measures oxygen saturation in newborns.

In order for the device to give normal readings, it is necessary to prepare the body for this procedure the day before:

Do not take any stimulants the day before;
Do not take tranquilizers during the last day;
Do not drink alcoholic beverages 2 days before the procedure;
Limit the intake of sedatives for a couple of days;
Do not smoke for at least a few hours before the pulse oximetry;
Do not eat 2-3 hours before manipulation;
Do not use cream in the places where the sensor will be attached.

Benefits of pulse oximetry

This method of instrumental diagnostics of blood composition has many advantages:

Non-invasive method for determining the concentration of oxygen in the blood, as well as the frequency and wave of the pulse;
The most accurate way to determine the functionality of the respiratory system;
Pulse oximetry can be used once for a preventive study, as well as for a long period of time in the treatment of hypoxia;
The procedure does not require professional medical knowledge;
Pulse oximetry is a simple yet reliable way to monitor oxygen in the body.

Pulse oximetry

Normative indicators of saturation in the composition of the blood and its deviations

The method of determining pulse oximetry is aimed at detecting the concentration of oxygen in hemoglobin, as well as at establishing the frequency and rhythm of the pulse. The saturation rate for children and adults is identical.

In order for the patient to correctly understand the indicators of saturation (SpO2), you can convert these data into an indicator of the partial pressure of oxygen molecules (PaO2):

At a normal level in arterial blood, saturation of venous blood can be 75.0%.

The indicator of venous blood with pulse oximetry is not so important, because the saturation of the cells of the body with oxygen occurs with the help of arterial blood molecules.

Learn - venous blood

When the oxygen concentration in the biological fluid drops to 94.0%, the doctor must take urgent measures to restore this indicator, because the critical figures for the development of hypoxia are 90.0%.

When the oxygen concentration is low, the patient needs emergency care in a hospital.

Saturation readings for pulse oximetry

If the saturation index is less than 90.0%, it is necessary to prescribe treatment with oxygen therapy;
At SpO2 85.0% and below, cyanosis of tissue cells develops;
At SpO2 of 90.0%, the pathology of cyanosis develops in newborns;
SpO2 70.0% is a sign of severe anemia;
Saturation of 80.0% is a sign of congenital heart disease and the development of cyanosis;
Pathology of obstruction of the aortic arch can be determined if SpO2 on the arms and legs has different indicators;
In a serious condition of the patient, the sensor shows the most correct index when it is installed on the earlobe.

The main etiology of the decrease in the saturation index is the occurrence of pathology in the body - arterial hypoxemia.

Causes of the development of arterial type hypoxemia

Hypoxemia can develop with such pathologies and disorders in the body:

With a reduced concentration of oxygen in the inhaled air;
In case of violation of hypoventilation of the lungs - night apnea, temporary cessation of breathing;
During surgery, shunting;
In case of pneumonia;
Pathology obstruction of the ways of the respiratory system;
lung collapse disease;
TELA;
Pathology fibrosis of the membrane of the alveoli and capillaries;
Atelectasis in multiple form;
Pathology Tetrad Falo;
heart defects;
Abnormal Structure of the Cardiac Organ, in which there is a single cardiac ventricle.

Complications of low concentration of oxygen molecules in the blood

The lack of qualified treatment of a low saturation index leads to hypoxemia, as well as to such pathologies in the body:

Convulsions of the whole body;
To damage to brain cells;
Decreased blood pressure index;
to myocardial hypoxia; During pregnancy, the development of hypoxia leads to an artificial interruption of the intrauterine formation of the fetus.
If a child has suffered hypoxemia in utero, then he has deviations in physical development and in intellectual abilities.

Preventive measures for hypoxemia
In order to prevent a decrease in saturation in the blood composition, and to prevent the development of hypoxemia in the body, simple preventive measures should be followed:
- Timely diagnose pathologies of the respiratory system;
- In bronchial asthma, diagnostic checks should be regular;
- Systematically undergo diagnostics of the cardiac organ and the system of blood vessels;
- If a pathology is detected that can reduce the concentration of oxygen in the composition of hemoglobin, it is necessary to begin immediate treatment;
- Control the level of iron in the body, and prevent the development of anemia;
- Follow the culture of food;
- Eat more fresh fruits, as well as vegetables and herbs;
- Take vitamins systematically for prevention;
- Do not drink alcohol;
- Give up nicotine addiction;
- Daily walks in the fresh air;
- Do therapeutic exercises of the respiratory system;
- Go in for sports - go to the pool, or on a treadmill;
- Adequate physical activity on the body;
- Do not stay in a dusty and smoky room.
Conclusion
The method of pulse oximetry is an opportunity to timely prevent many pathologies in the body, including pathologies that lead to death.
Pulse oximetry is gaining popularity in many countries, and the use of a portable pulse oximeter is also necessary for monitoring health, as is the use of a tonometer for fluctuations in blood pressure, and a glucometer for monitoring blood glucose index.

This is a method for measuring indicators: blood saturation, pulse rate and pulse wave amplitude.
The term oxygen saturation means the oxygen saturation of hemoglobin, or more precisely, it is the percentage of oxyhemoglobin to total hemoglobin.
Devices that measure blood saturation are called pulse oximeters.

For the first time, the method of pulse oximetry began to be used in intensive care units. Over time, the method improved, the quality of the equipment improved, and this study became publicly available. Currently, it is used even on an outpatient basis.

Benefits of pulse oximetry:

Non-invasive, painless method for determining saturation, pulse rate and pulse wave amplitude;
Sufficiently accurate method for determining the function of respiration;
Can be used for both single examination and long-term monitoring;
Does not require special medical knowledge, calibration and special maintenance;
The method is quite simple and reliable to use.

The method of pulse oximetry is based on the ability of hemoglobin to absorb light of a certain length, and this degree of absorption depends on the percentage of oxyhemoglobin. That is, pulse oximert is able to distinguish between oxyhemoglobin and reduced (deoxygenated) hemoglobin. In addition, the pulse oximeter is able to determine oxyhemoglobin in the arterial blood (by the pulsation of the light flux), and not in the venous.

The pulse oximeter will also be determined by filling the arterioles (during the pulse wave) - the pulse rate and the amplitude of the pulse wave.

The sensor of the device is equipped with two LEDs (one of them emits red light rays, and the other infrared) and a photodetector, which receives the rays passing through the tissues. Infrared light adsorbs oxygenated hemoglobin, and red light adsorbs deoxygenated hemoglobin.

To conduct a study, a sensor is put on the finger. LEDs emit light, which, passing through the tissues and blood capillaries of the finger, is perceived by the photo sensor. The sensor registers a change in the color of hemoglobin depending on its saturation with oxygen and displays the result on the monitor display.

Pulse oximeters are:

Transmission - which work in the light through the tissue.
Refractive - work by reflecting light from the tissue. Unlike transmission ones, they have a number of advantages: they can be used with painted, false nails, the sensors do not have to be opposite each other.

Denote the saturation determined by the pulse oximeter with such symbols - SpO2.
If the saturation was determined by the laboratory (invasive) way, the so-called true saturation, then it is denoted by the symbols - SaO2.

Saturation rate (SpO2) - 95-98%.

To correctly understand the saturation figures, you can compare them with the partial pressure of oxygen in the blood (PaO2).

So saturation (SpO2) 95-98% corresponds to - 80-100 mm Hg. Art. (PaO2).

Saturation (SpO2) 90% corresponds to - 60 mm Hg (PaO2).

Saturation (SpO2) 75% corresponds to - 40 mm Hg (PaO2).

Rules for conducting pulse oximetry:

The sensor needs to be installed correctly. Fixation should be reliable, but without excessive pressure;
The sensors must be located opposite each other, symmetrically, otherwise the path between the sensors will be unequal and one of the wavelengths will be "overloaded". In this case, changing the position of the sensor leads to a change in saturation. This only applies to transmission pulse oximeters;
After attaching the sensor to the patient, you need to wait a little (about 5-20 seconds), after which the device will show the result;
The nail must be clean (no polish). Various contamination of the nail reduces the percentage of saturation (this does not apply to refractive pulse oximeters);
Any movements, tremors distort the result of saturation;
Bright external light also affects the readings of the instrument;
You should know that in case of carbon monoxide poisoning, saturation will be within the normal range (carboxyhemoglobin is mistakenly perceived by the device as oxyhemoglobin);
With anemia, saturation will, on the contrary, be increased (compensatory), because it does not depend on the amount of hemoglobin, but on the percentage of oxyhemoglobin to all hemoglobin;
If the microcirculation is disturbed (vasospasm), when the pulse wave is not detected on the device, the pulse oximeter will show inaccurate results. If the pulse oximeter is of high quality, it will indicate that it is impossible to determine the result, and if it is not of high quality, it can show a saturation of -100%;
If during the determination - the saturation changes rapidly (for example, from 95% to 80% and vice versa), then you need to think about the error of the device;
When the saturation is lowered below 70%, the error of the method increases;
In case of heart rhythm disturbances, the perception of the pulse signal by the pulse oximeter is disturbed;
Jaundice, dark skin, gender, age have practically no effect on the performance of the pulse oximeter.

The main reason for the decrease in saturation is the development of arterial hypoxemia.

Arterial hypoxemia may occur:

With a decrease in oxygen in the inhaled gas. This is possible with an excessive concentration of nitrous oxide during anesthesia. Also when breathing rarefied air in the highlands;
In conditions that lead to hypoventilation (apnea, during tracheal intubation with the use of muscle relaxants);
With shunting of blood in the lungs (respiratory distress syndrome RDS);
With hypoventilation of individual lung zones (airway obstruction, pneumonia, macro and microatelectasis of the lungs);
In violation of the diffusion of oxygen through the alveoli into the blood (extensive pneumonia, lung collapse, multiple atelectasis, pulmonary embolism, edema or fibrosis of the alveolocapillary membrane);
With congenital heart defects, when there is a discharge of blood from right to left (Fallot's tetrad), or a general mixing of blood (a common arterial trunk, a single ventricle of the heart).

For a practitioner, you need to know:

When saturation is less than 90%, oxygen therapy is indicated;
Cyanosis occurs when SpO2 is less than 85%, in newborns already at SpO2 - 90%;
With anemia, even with a saturation of 70%, there may not be cyanosis (anemia hides cyanosis);
Saturation of 80% occurs with congenital heart defects, which are accompanied by cyanosis;
A saturation difference between the arms and legs may indicate obstruction of the aortic arch (at the isthmus of the aorta);
In critical conditions, an ear-mounted sensor is preferred over a finger-mounted sensor;
To check the operation of the pulse oximeter, first determine the saturation in a sitting position (the hand is on the table). Then they stand up, raise their hand and again determine the saturation. Saturation should be the same. If it does not match, this means that the pulse oximeter is not suitable for monitoring patients;
If the pulse oximeter shows 100% when the patient breathes atmospheric air, then this is a sign that it is not of high quality;
Pulse oximetry characterizes only oxygenation and is not an indicator of ventilation;
Using a pulse oximeter, you can determine the decrease in tissue perfusion (by reducing the amplitude of the pulse wave on the photoplethysmogram). Moreover, if there is no pulmonary pathology, the saturation will be normal.

In conclusion, I would like to note that the pulse oximeter does not provide information on the oxygen content in the blood, the amount of oxygen dissolved in the blood, respiratory rate, tidal volume, blood pressure, cardiac output. Therefore, it is necessary to use additionally other research methods to determine the complete clinical picture.

The body's main stimulus for respiration is an increase in carbon dioxide (CO2) levels. The brain controls ventilation. With the help of muscle contractions, air (usually composed of 79% nitrogen and 21% oxygen) enters the lungs through the respiratory tract and fills the alveoli, where gas exchange occurs. It is done by a process called "diffusion" - the movement of molecules from an area of high concentration to an area of low concentration. This diffusion occurs across the alveolar capillary membrane, where CO2 in the blood is exchanged for oxygen (O2) from the air. The oxygen binds to hemoglobin molecules in red blood cells. Oxygenated blood travels from the lungs to the heart, from where it travels through the arteries throughout the body. The saturation of arterial hemoglobin with oxygen is called saturation (SaO2). SaO2 values > 94% are considered normal. At lower values, oxygen therapy is used. A modern oxygen concentrator is a small, easy-to-operate device.

How pulse oximetry works

Pulse oximetry is performed using a pulse oximeter. The pulse oximeter is a non-invasive means of measuring both pulse rate and arterial hemoglobin oxygen saturation at the peripheral capillary level. It consists of a portable monitor and a photoelectric probe that is attached to the patient's finger, finger, toe, or earlobe. The probe measures the amount of red color in the capillary during systole and diastole. The monitor calculates the time between peaks and shows the pulse rate in beats per minute. The device also calculates a value based on the light absorption coefficient in systole and diastole and shows the peripheral percentage of oxygen saturation (SpO2).

If the pulse oximeter shows a saturation below 92%, then this is cause for concern. Its fall below 90% is suggestive of hypoxemia. This means that the concentration of oxygen in the bloodstream is lower than in the cells. This makes it difficult for oxygen to diffuse out of the cells and back into the bloodstream, leading to tissue hypoxia and eventually death. A saturation of 94-99% is ideal, but be aware of factors that can affect the pulse oximeter reading. Conditions that can make readings unreliable include poor peripheral perfusion, including those caused by shock, vasoconstriction (narrowing of the blood vessels), and hypotension (low blood pressure). Do not attach a sensitive probe to an injured limb. Do not use the device on the same arm on which blood pressure is measured. Keep in mind that the pulse oximeter reading will go down while the blood pressure cuff is inflating. It will close the arterial blood flow, affecting the readings,

The changes taking place in the field of medicine, as well as the electronic portable devices associated with them, can be called truly revolutionary. Devices that were previously only found in hospitals are now available for home medical use. A good example is the home oxygen concentrator. Accordingly, pulse oximeters are used by nurses in hospitals, outpatients at home, fitness enthusiasts at the gym, and even pilots on airplanes. the most informative method for determining the oxygen content in the blood.

Pulse oximetry. Degrees of oxygen deficiency relative to saturation (SpO2) - pulse oximeter readings

Recommendations, the required flow of oxygen, the mode and duration of oxygen therapy, are prescribed by the attending physician! Oxygen therapy at home is carried out using a pulse oximeter under the control of indications.

By the level of blood oxygen saturation, one can judge the metabolism in tissues and the function of the main organ systems. To measure this indicator, a non-invasive method of pulse oximetry is also used.

The principle of operation of pulse oximetry and the method of conducting pulse oximetry using a sensor - what is the difference between the transmission method and the reflected one

- a method for determining the amount of oxygen associated with hemoglobin in arterial blood. Up to four oxygen molecules can attach to each hemoglobin molecule. The average percentage of saturation of hemoglobin molecules is the oxygen saturation of the blood. 100% saturation means that each hemoglobin molecule in the studied volume of blood carries four oxygen molecules.

How a pulse oximeter works is based on the differentiated absorption of light with different wavelengths by hemoglobin, depending on the degree of oxygen saturation.

The pulse oximeter consists of a light source of two wavelengths (660 nm "red" and 940 nm "infrared"), a photodetector, a processor, and a monitor.

Pulse oximeter software Allows the device to extract the pulse volume of blood (arterial component).

Most models provide audio and graphic representation of the degree of oxygen saturation. It takes 5-20 seconds to calculate the saturation.

There are two types of pulse oximetry:

Transmission.

For analysis, a light wave is used that passes through the tissues of the body. The emitting and receiving sensors are located opposite each other. For research, the light source and the photodetector are fixed on the finger, earlobe, wing of the nose.

reflected.

The reflected light wave is used for analysis. The emitting and receiving sensors are located side by side. The device can measure oxygen saturation in different parts of the body (forearm, face, lower leg, abdomen, etc.).

The main advantage of reflected pulse oximetry is its ease of use. The part of the body for attaching the sensors is selected depending on the patient's condition, the presence of a forced position of the body. The accuracy of reflected and transmission pulsometry is approximately the same.

When to do computerized pulse oximetry - indications

Applications of pulse oximetry:

The decision on the need for research is made by the attending physician.

Main indications for pulse oximetry:

Respiratory failure (including probable).
oxygen therapy.
Postoperative period (after restoration of the vascular wall, orthopedic operations, interventions on the distal parts of the body).
Severe chronic diseases accompanied by a high risk of hypoxia.
Suspicion of obstructive sleep apnea syndrome, central sleep apnea syndrome and chronic nocturnal hypoxemia.

How is pulse oximetry done at night?

Pulse oximetry at night indicated for suspected sleep disturbances. Such disorders are likely in patients with II-III degree obesity, diabetes mellitus, hypothyroidism, as well as in metabolic syndrome, arterial hypertension.

Symptoms of disturbed breathing during sleep are often snoring, arrhythmia, nocturia, daytime sleepiness, headaches and weakness in the morning, gastroesophageal reflux at night.

Pulse oximetry at night is a long-term monitoring of oxygen saturation, pulse rate, pulse wave amplitude. During sleep, the pulse oximeter records indicators 10-30 thousand times. The data is processed by software and stored in the instrument's memory.

For the study, a portable device is used. Night sleep can be monitored both at home and in a medical facility.

Principles of diagnostic research:

Regular research hours are 22.00-8.00.
In the sleeping room, the normal temperature regime (18-25 degrees Celsius) should be observed.
Avoid sleeping pills and caffeine before nighttime pulse oximetry.
The patient is given a "study diary" form to record the time of awakening, medication, headache, etc.

Night pulse oximetry algorithm:

A receiving unit with a microprocessor is fixed on the left wrist, and a device sensor on one of the fingers of the left hand.
After installing the sensor, the device automatically turns on, the values of the indicators appear on the display of the receiving unit.
Further, the patient does not remove the sensor from the phalanx of the finger throughout the night. All night awakenings are recorded in the “research diary”.
After waking up in the morning, the patient removes the transducer and the receiving unit, passes the "study diary" to the doctor.

Basic indicators and norms of pulse oximetry

Pulse oximetry measures arterial hemoglobin saturation with oxygen and pulse rate (heart rate).

Norma arterial hemoglobin saturation with oxygen say 95-98%. Higher numbers may be with oxygen therapy. Values below 95% indicate hypoxia.

In pediatric practice, saturation values above 95% are most often considered the norm.

Pulse rate at rest in adults should normally be 60-90 per minute.

In children, this indicator is assessed according to the age norm (the younger the child, the higher the pulse rate).

Where can I get high-quality computer pulse oximetry?

In Moscow, pulse oximetry can be done in several institutions, including:

Night pulse oximetry is performed in:

Sleep Laboratories on the basis of the Department of Systemic Hypertension of the Institute of Clinical Cardiology. A. L. Myasnikova Federal State Budgetary Institution "Russian Cardiological Research and Production Complex".
Department of Sleep Medicine, Federal State Budgetary Institution Clinical Sanatorium "Barvikha".
Children's consultative and diagnostic center.
Consultative and diagnostic center "Arbatsky".

Pulse oximetry price:

The minimum pulse oximetry costs from 100 rubles (Southern Clinic).
Computer monitoring costs from 1500 rubles (FGBU Clinical Hospital).
Night pulse oximetry will cost at least 2,500 rubles (Children's Consultative and Diagnostic Center, Arbatsky Consultative and Diagnostic Center).

In most major cities, pulse oximetry is available in private and public hospitals. You can find out exactly where to undergo the study from your doctor.

The well-established method of monitoring computer pulse oximetry is a non-invasive examination technique that is needed to determine the amount of oxygen in the blood. During the study, the values of oxyhemoglobin are revealed, on the basis of which the result is based.

The procedure is based on the examination of arterial blood. A decrease in oxygen in it leads to a deterioration in the condition, a decrease in vitality. The pulse oximeter is intended only to determine the amount, without changing it. Additionally, it measures and records every change in the pulse wave. In this article, you will find detailed information about the method of pulse oximetry and its technique.

Who is pulse oximetry for?

Diagnostics is used in different areas. So at the appointment with a cardiologist, you can be assigned pulse oximetry during:

Plastic and vascular surgery. The technique is necessary for oxygen saturation and pulse control.
Resuscitation and anesthesiology. Here, the device is needed when transporting the patient, to confirm cyanosis.
In obstetrics, it is needed to diagnose fetal oximetry.
Neonatology. In this case, the device is connected to premature babies, which helps to identify various abnormalities (damage to the lungs, retina, etc.).
Therapy. Indispensable for determining the effectiveness of drug treatment, helps to identify apnea and respiratory failure.
In pediatrics, pulse oximetry is used as a non-invasive monitoring method.

This video in English tells quite thoroughly about the method of pulse oximetry:

What is she for?

Pulse oximetry should be done for a number of diseases, the list of which includes:

obesity,
severe COPD,
metabolic Syndrome,
hypothyroidism.

The procedure is important for determining the amount of oxygen in the blood. In the presence of cyanosis, respiratory arrest during sleep, apathy, drowsiness and sweating, you should consult a doctor. Deviations detected by pulse oximetry can be eliminated in time, which is important for health.

You can repeat the examination every year, and if there are indications, it is better to do pulse oximetry once a month or two.

Types of procedure

There are the following types of pulse oximeters:

waist,
shoulder,
stationary,
sleep monitors.

The study itself is of 2 types:

Reflected. The analysis is subject to the luminous flux, which is reflected from the tissues. If this type of study is performed, then the sensor can be placed anywhere on the body.
transmission. The light flux that passes through the tissues is analyzed. The device must be fixed on the wing of the nose, ear or finger.

Indications and contraindications for

Indications for pulse oximetry are:

oxygen therapy;
respiratory failure;
risk of hypoxia (including in various chronic processes);
prolonged anesthesia;
chronic hypoxemia;
postoperative period (especially with distal interventions, operations to restore the wall of blood vessels or orthopedic surgery);
different types of apnea or suspicion of it.

The procedure has no contraindications.

Is the method safe

Pulse oximetry is completely safe and painless, which distinguishes it favorably from invasive examination methods.

Preparation for the procedure

You can not use any stimulant before the study.
The ban includes drinks with caffeine, as well as sedatives, tranquilizers.
A couple of hours before bedtime, they completely refuse food, and then a bad habit should be excluded for this time.
Cream should not be applied to the hands if the pulse oximeter will be attached in this area.

How it goes

You can install the sensor yourself, following the instructions:

The pulse oximeter is put on the finger at the time of preparation for sleep. The retainer should be located above the nail plate.
The end of the finger must not be further than the stopper limit.
Once the instrument is installed, the oximeter will automatically turn on. In the next 20 seconds, a study of the level of oxygen saturation is carried out, after which the result will be displayed on the screen. It will be indicated as a percentage, and there will be heart rate data nearby.
Next, you need to go to bed. Data recording will continue continuously for another 16 hours. After waking up, the device must be turned off, and then it is handed over to doctors to decrypt the data.

Read below about the norm indicators in adults and children according to pulse oximetry.

For more information on how pulse oximetry is performed, see the video below:

Deciphering the results

The somnologist conducts decoding.

The norm is considered to be blood saturation with hemoglobin up to 98%, and if the values are close to 90%, then this indicates hypoxia. Saturation indicators should be more than 95%.
If we talk about children, then here at each age there will be a norm. If the data shows 100% oxygen saturation, then deep breathing is inferred during sleep. The same result is obtained when using oxygen mixtures.
With obstructive sleep apnea, saturation can be 80%, which is a critical mark. The indicator indicates that during sleep there are significant difficulties in respiratory activity. This often requires respiratory support at night.

The price of pulse oximetry is discussed below.

Average cost of the procedure

The procedure at night will cost about 2500 rubles, and sometimes less. Your doctor will tell you where to get pulse oximetry done.

The role of pulse oximetry in the treatment of sleep disorders will be discussed in this video: