RU2412644C1 - Method for determination of indications for polysomnography in patients with obstructive sleep apnea syndrome - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: group of inventions refers to medicine, namely to cardiology. A first invention describes anthropometric data: height, weight, waist circumference (WC) and hip circumference (HC). A body weight index (BWI) and a WC/HC ratio are calculated. The presence of sleep apnea is proven, and if the BWI is more than 30 kg/m², the WC/HC ratio is more than 1.0, age over 30 years old in men and over 50 years old in women, as well as if observing proven sleep apnea, pulseoxymetry study is required, and if pulseoxymetry data show evident desaturation - less than 80% and/or frequent desaturation episodes - more than 20 per 1 hour of sleeping, polysomnography is considered to be indicated. A second invention describes anthropometric data: height, weight, waist circumference (WC) and hip circumference (HC), the body weight index (BWI) and WC/HC ratio are calculated, while the following criteria are detected, including: 1 criterion - loud broken night snore, 2 - more frequent night urination, 3 - long-run nocturnal sleep disturbance - more than 6 months, 4 - excessive daytime sleepiness, 5 - a patient considers to have overweight or obesity, 6 - arterial hypertension, and if the BWI is more than 30 kg/m², the WC/HC ratio is more than 1.0, age over 30 years old in men and over 50 years old in women, as well as if observing the presence of at least three criteria of those mentioned above, pulseoxymetry study is performed, and if pulseoxymetry data show evident desaturation - less than 80% and/or frequent desaturation episodes - more than 20 per 1 hour of sleeping, polysomnography is considered to be indicated.

EFFECT: method enables higher detectability of said pathology and as a result provides pathogenetic therapy in the patients.

2 cl, 1 ex

Description

The invention relates to medicine, namely to cardiology. The following types of breathing disorders during sleep are distinguished: obstructive sleep apnea syndrome (OSAS), central sleep apnea syndrome, hypoventilation / hypoxemia syndrome, and unclassified respiratory disorders during sleep.

Data from a number of large population studies have shown that the incidence of OSAS in men depends on age and ranges from 0.4% in younger age groups to 9.1% in older groups; in women, these indicators are 0.4 and 4.4%, respectively. It was found that if the frequency of OSAS in the general population varies between 0.3-1.1%, then among men over 60 it reaches 15-73%; in women, this figure is much lower. According to generalized data, the frequency of OSAS among the population varies from 2 to 10%, increasing with age. It is higher in men, and in patients with arterial hypertension (AH) it is 26-40% (0-12% in the control group). It has been established that the so-called natural sudden death of older people in a dream is often caused by COAC manifestations (Young T., Peppard R.E., Gottlieb DJ Epidemiology of obstmctive sleep apnea: a population health perspective. Am. J. Respir. Crit. Care Med . 2002; 165: 1217-1239).

According to the recently updated International Classification of Respiratory Disturbances during Sleep, published by the American Academy of Sleep Medicine, a diagnosis of OSA can be made if the index of respiratory distress (IND) is ≥ 15, regardless of whether the patient has clinical manifestations, or an IND> 5 in combination with the following clinical manifestations: 1) paroxysmal sleep; severe daytime sleepiness; non-refreshing sleep; weakness or insomnia; 2) sudden awakenings at night with a sense of shock; 3) loud snoring, often in combination with intermittent respiratory arrest, as noted by the patient's relatives (American Academy of Sleep Medicine (AASM). International Classification of Sleep Disorders. Westchester, AASM, 2005). The definition and classification of the various types of breathing disorders associated with sleep have been clarified in recent decades. In particular, apnea of both central and obstructive genesis, hypopnea and awakening caused by respiratory efforts and some others were highlighted.

The gold standard for diagnosing OSAS and related respiratory disturbances during sleep is polysomnography (PSG) throughout the night. (Belov A.M. Analysis of the sleep process in polysomnography, Moscow, 2000).

When recording a full polysomnography, the following parameters are recorded:

1. Electroencephalogram using surface bipolar leads (C3 / A2, C4 / A1, O2 / A1 and O1 / A2).

2. Electrooculogram (EOG).

3. Electromyogram from the chin muscles.

4. Rotonosal air flow, determined using a thermocouple.

5. Respiratory movements of the chest and abdominal wall by induction plethysmography.

6. The body position of the subject.

7. Blood saturation with oxygen (SpO ₂ ) by pulse oximetry (photoplethysmographic sensor on the finger).

8. Electrocardiography (ECG).

9. Myogram from the anterior tibial muscles.

10. The presence and duration of periods of snoring using vibration sensors.

However, there are a large number of difficulties, primarily associated with the complexity and high cost of PSG. In this regard, increased attention has recently been paid to the development of simpler diagnostic methods for OSA, as well as respiratory disorders during sleep in general, for clinical practice.

The saturation of arterial blood with oxygen is one of the fundamental parameters, which is an integral part in the diagnosis of certain breathing disorders during sleep. With OSAS, a single episode can be diagnosed as significant when it is followed by a decrease in blood oxygen saturation - desaturation. The severity of desaturation is also an indicator of the severity of these disorders. In this connection, the measurement of this parameter should be an integral part of the clinical examination of the patient, along with such routine examination methods as measuring respiratory rate, blood pressure and pulse, and the doctor should have a pulse oximeter in addition to a stethoscope and tonometer. In developed countries, pulse oximeters for single measurements are widely used not only by pulmonologists and cardiologists, but also by general practitioners. In recent years, portable computer pulse oximeters have also become widespread in the world, which allow you to monitor the saturation of arterial blood with oxygen for many hours, including the period of night sleep. Unfortunately, only resuscitation and intensive care units are equipped with pulse oximeters in Russia. Outside of these departments, the pulse oximetry technique has not been widely used. Moreover, the problem is not so much in the cost of equipment (currently the price of a pulse oximeter for single measurements is about 10,000 rubles, for monitoring - about 40,000 rubles), but in the lack of awareness of doctors about the benefits that the use of pulse oximeters can bring in everyday clinical practice. Pulse oximetry is a non-invasive method for measuring the percentage of oxyhemoglobin in arterial blood (SpO ₂ ). A quantitative assessment of the frequency of desaturation per hour (desaturation index) allows you to indirectly judge the frequency of episodes of apnea / hypopnea per hour (apnea / hypopnea index). Since the apnea / hypopnea index is the main criterion for the severity of OSAS and central sleep apnea syndrome (SCAS), in fact, pulse oximetry makes it possible to predict with a high degree of certainty the severity of obstructive and central respiratory disorders in sleep. The use of pulse oximetry for the diagnosis of respiratory disorders in sleep, on the one hand, is highly effective, and on the other, economic feasibility. Given the ease of use and ease of use, pulse oximetry can be recommended for use both in specialized dispensaries in outpatient practice and in hospitals as a screening method.

At the same time, the clinic has a large number of patients who complain similar to obstructive sleep apnea syndrome, for example, with primary snoring, or patients who do not have clinically significant respiratory disorders during sleep, which leads to the need for expensive research methods. This determines the feasibility and relevance of developing simple approaches to the diagnosis of OSAS, including those based on questionnaires and questionnaires. Our questionnaire was based on patient complaints proposed in the monograph by J.R. Stradling in 1991. This questionnaire consisted of 7 questions and looked like this:

1. Indications of respiratory arrest during sleep (no / yes) 2. Loud or intermittent night snoring (no / yes) 3. Rapid night urination (no / yes) 4 Long-term disturbances of night sleep (> 6 months) (no / yes) 5. Increased daytime sleepiness (no / yes) 6. Obesity (no / yes) 7. Arterial hypertension (no / yes)

A positive answer to the first question or at least 3 positive answers from questions 2 to 7 are enough to make a diagnosis of OSAS. Based on our experience, we began to note that, despite the criteria described for this questionnaire, false-positive and false-negative results are often obtained. In this regard, we added a number of anthropometric indicators to these clinical signs, such as height, weight, body mass index, which was calculated using the Ketle formula as the ratio of body weight (kg) to height (m) squared, waist circumference (OT ) and hips (OB) and their relationship, as well as age with different thresholds. Moreover, BMI was considered an indicator of normal body weight of less than 25 kg / m ² , and threshold values of BMI of more than 30 kg / m ^{2 as a} criterion for the diagnosis of obesity. An RT / OB ratio of more than 1.0 was considered a threshold value for this indicator. It is known that in men older than 30 years and in women older than 50 years, the incidence of OSA increases, which was taken in the indicator age for threshold values.

The Stradling profile we modified is as follows:

FULL NAME. Date of completion Slave tel. House. tel. Mobile phone Age Height The weight Waist Hips No. Sign Yes No one Indications of respiratory arrest in a dream (e.g. from relatives) 2 Loud intermittent night snoring 3 Rapid night urination four Prolonged disturbance of night sleep (more than 6 months) 5 Increased daytime sleepiness 6 Overweight or obesity 7 Arterial hypertension (especially night and morning)

Subsequently, we compared the results of our modified questionnaire with the data of PSG and / or cardiorespiratory monitoring, as a result, we received a greater diagnostic value of our modified questionnaire compared to the Stradling questionnaire. The modified Stradling questionnaire makes it possible to take into account not only the main complaints of patients with OSAS, but also additionally identify risk factors for the development of OSAS, such as obesity, metabolic syndrome, age, which allows to increase the predicted frequency of diagnosis of respiratory disorders during sleep and to provide a greater number of patients with pathogenetic therapy. Therefore, an additional study of patients over the age of 30 for men and over 50 for women with a BMI of more than 30 kg / m ² , RT / OB of more than 1.0 increases the detection of respiratory disorders during sleep of an obstructive type.

Thus, when contacting a patient with suspected OSA, the diagnostic search algorithm should include the following steps:

If OSAS is suspected during the initial visit to a doctor (clinic, hospital, etc.), the patient will be asked to fill out a questionnaire, which was modified by us and was first validated as part of the work.

With a high suspicion of the presence of OSA according to the questionnaire, the next step in the diagnosis should be a screening non-invasive study of the oxygen content in capillary blood - pulse oximetry. If a pronounced desaturation is detected - less than 80% and / or frequent episodes of desaturation - more than 20 for 1 hour of sleep, the patient should be sent to a hospital (sleep center, sleep laboratory) equipped for polysomnography or cardiorespiratory studies. We believe that such a continuity between primary care (polyclinic) and specialized medical care (sleep laboratory) will not only increase the detection rate and provide timely specialized treatment of OSAS, but will also be cost-effective by reducing the number of false positive cases of OSAS diagnosis.

After the diagnosis of OSA and the patient’s presence of moderate (more than 20 episodes of respiratory arrest per 1 hour of sleep) or severe (more than 40 respiratory arrests per 1 hour of sleep), the patient should be selected for pathogenetic treatment.

Thus, for the verification of OSAS, there is a “gold standard” for diagnosis - polysomnographic research or its possible equivalent cardiorespiratory monitoring. However, these studies can only be carried out in a hospital: a sleep center or a specialized laboratory with special equipment and trained medical personnel, which, in turn, due to the high level of time and financial costs does not allow the use of these methods as screening tests, leading to the main paradox of the problems under consideration: the high prevalence of pathology in the population and at the same time its low detectability. This makes it necessary to develop simple and time-saving financing screening methods that can allow doctors to identify patients with this pathology during initial contact, for subsequent referral to specialized institutions. The proposed method of phased examination, i.e. determination of indications for polysomnographic studies in patients with respiratory disorders during sleep, allows to increase the detection of this pathology and, as a result, providing patients with pathogenetic therapy.

Stradling's modified questionnaire has proven high sensitivity and specificity for the diagnosis of obstructive sleep apnea during sleep of varying severity.

Example 1

Patient A., 55 years old, height - 180 cm, weight - 128 kg, BMI - 39 kg / m ² , OT - 100 cm, OB - 100 cm, OT / OB - 1.0. Office HELL 176/112 mm Hg Heart rate (HR) - 90 beats. in minutes He complained of snoring, a refreshing dream, pronounced daytime sleepiness.

The patient was asked to fill out our modified questionnaire, a variant of which is given below:

Age 55 years Height 180 cm The weight 128 cm Waist 100 cm Hips 100 cm No. Sign Yes No one Indications of respiratory arrest in a dream (possibly from relatives) + 2 Loud intermittent night snoring + 3 Rapid night urination + four Prolonged disturbance of night sleep (more than 6 months) + 5 Increased daytime sleepiness + 6 Overweight or obesity + 7 Arterial hypertension (especially nocturnal and / or morning) +

A positive answer to the 1st question or at least 3 positive answers from 2 to 7 points are usually enough to solve the question of referral for further examinations. At the same time, given the likelihood of false positive answers, it was additionally possible to evaluate anthropometric data in the submitted questionnaire. So, this patient had a 2nd degree of obesity, BMI was 39 kg / m ² , and he was older than 50 years. Thus, according to the results of the questionnaire, it was possible to assume with a high degree of certainty that this patient has some kind of obstructive respiratory failure during sleep. Moreover, to confirm this assumption, the patient underwent a pulse oximetric screening examination. We found that arterial oxygen saturation decreased to 76%, and the number of desaturation episodes per 1 hour of sleep was 34.6 episodes. These changes correspond to severe manifestations of obstructive sleep apnea, however, to confirm the diagnosis and make a final decision on the appointment of pathogenetic therapy, the patient was recommended to conduct cardiorespiratory monitoring. As a result of the interpretation of this study, the following results were obtained: the apnea-hypopnea index was 56 events per hour. The longest respiratory arrest was 47 seconds. The desaturation index was 57 events per hour, the minimum saturation was 74%. These changes correspond to severe OSAS. The patient was offered CPAP therapy with the selection of optimal parameters in the automatic mode and assessment of clinical significance the day after the study. After deciphering the results of CPAP therapy from the device’s memory, we received: YAG became 4.7 sob. per hour, which corresponds to normal values during sleep (the norm is up to 5 sob per hour). Thus, the consistent use of all stages of the examination, followed by the appointment of pathogenetic CPAP therapy, has shown the effectiveness, safety and therapeutic value of using our algorithm.

After 7 days of using CPAP therapy, the patient was invited to the clinic to assess the clinical significance, effectiveness and adequacy of the parameters of the selected treatment. When reading the treatment parameters from the memory of the apparatus of the treatment results in automatic mode, we received a decrease in YAG to 3.3 sob. in hour. Blood pressure decreased to 144/90 mm Hg, heart rate - 72 beats. in min., without changing the drug therapy during the use of CPAP therapy. In the future, we observed this patient for a long time (more than 3 years). We noted that the patient reduced weight by 12 kg, against the background of the same dietary recommendations that the patient had observed earlier, but without significant weight loss before the start of CPAP therapy, almost normal blood pressure and heart rate figures remained, without changing the antihypertensive therapy. The patient himself noted the disappearance of daytime sleepiness, increased efficiency, improved memory and potency. The described positive changes testify to the adequacy of our proposed examination algorithm and the effectiveness of the selected treatment.

This scheme of examination and treatment is actively used in the systemic hypertension department of the Cardiology Institute. A.L. Myasnikov RKNPK MZ and SR of the Russian Federation. In total, at this point more than 700 patients were successfully examined according to the proposed algorithm.

Claims (2)

1. A method of determining indications for a polysomnographic study in patients with respiratory disorders during sleep, characterized in that they determine anthropometric indicators: height, weight, waist circumference (OT) and hips (OB), calculate the body mass index (BMI) and OT / OB ratios determine the presence of respiratory arrest in a dream, and with a BMI of more than 30 kg / m ² , OT / OB of more than 1.0, over 30 for men and over 50 for women, and also if there are respiratory arrest a pulse oximetric study is carried out in a dream, and when According to pulse oximetry data of expressed desaturation - less than 80% and / or frequent episodes of desaturation - more than 20 per 1 hour of sleep, polysomnography is considered to be indicated. 2. A method for determining indications for a polysomnographic study in patients with respiratory disorders during sleep, characterized in that they determine anthropometric indicators: height, weight, waist circumference (OT) and hips (OB), calculate the body mass index (BMI) and OT / OB ratios determine the presence of the following indicators: 1 indicator - loud intermittent night snoring, 2 - frequent nightly urination, 3 - prolonged disturbance of night sleep - more than 6 months, 4 - increased daytime sleepiness, 5 - the patient believes that he has I'm overweight or obese, 6 - arterial hypertension, and BMI over 30 kg / m ^2, OT / OB greater than 1.0, the age of 30 for men and over 50 for women, as well as the presence of at least three indicators from among 1-6 indicators, a pulse oximetric study is carried out, and if pulmonary oximetry shows a pronounced desaturation of less than 80% and / or frequent episodes of desaturation - more than 20 for 1 hour of sleep, polysomnography is indicated.