RU2557904C1 - Diagnostic technique for chronic foetal hypoxia - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: technique involves foetus's middle cerebral artery Doppler ultrasonography prior to and after a pregnant woman holds her breath as much as possible at a depth of inhale. Diagnostically significant indices of blood velocity curves resistance in the foetus's middle cerebral artery that are a systolic/diastolic ratio, a resistance, a pulsation index are measured with a breath-holding test conducted and taking into account foetus's daily rhythmostasis. If the Doppler ultrasound measures are: the systolic/diastolic ratio at 12.00 prior to breath-holding 3.71±0.05, after breath-holding 4.56±0.08 and at 20.00 prior to breath-holding 3.92±0.06, after breath-holding 4.74±0.09; the resistance at 12.00 prior to breath-holding 0.69±0.03, after breath-holding 0.87±0.04 and at 20.00 prior to breath-holding 0.80±0.03, after breath-holding 0.91±0.04; the pulsation index at 12.00 prior to breath-holding 1.78±0.04, after breath-holding 1.92±0.03 and at 20.00 prior to breath-holding 1.84±0.04, after breath-holding 1.97±0.04, changes in the foetus's functional status are detected and chronic foetal hypoxia is diagnosed.

EFFECT: technique enables increasing the diagnostic accuracy in chronic foetal hypoxia by measuring the functional parameters taking into account the time variations of daily rhythmostasis.

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Description

The invention relates to medicine, namely to obstetrics and gynecology, and relates to a method for diagnosing chronic fetal hypoxia.

Early diagnosis of chronic fetal hypoxia is a prerequisite for the successful provision of medical care to pregnant women and their newborns, since ischemic damage to the central nervous system of the fetus in the structure of causes of perinatal mortality is 60-70% and 80% is the cause of childhood disability (A. Strizhakov , Lipatov I.S., Tezikov Yu.V. Placental insufficiency: pathogenesis, prognosis, diagnosis, prophylaxis, obstetric tactics. - Samara: LLC "Etching", 2014).

The application in practical work of knowledge about the temporal organization of the physiological systems of the mother, fetus, newborn and their relationship with the positions of biorhythmology, the spatio-temporal organization of the mother-fetus-newborn system allows you to get the most complete picture of the course of the gestational process, the state of the fetus. One of the effective approaches to solving the problem of monitoring the state of the fetus during pregnancy and childbirth is the biorhythmological approach to assessing cerebral hemodynamics, which makes it possible to identify a high perinatal risk group for cerebral ischemia (Tezikov Yu.V., Lipatov I.S., Dremlyuga N. M., Kozlova IV A biorhythmological approach to assessing the status of the fetoplacental complex and newborns. Ural Medical Journal. Perinatology. - 2008. - No. 12 (52). - P. 152-159).

A known method for the diagnosis of chronic hypoxia of the fetus by applying cardiotocographic examination of the mother and the fetus (Sidorova I.S., Makarov I.O. Research methods during pregnancy and childbirth. Standard and new technologies: a training manual. - M .: "MEDpress-inform" , 2005 .-- 128 s.).

In the known method for the diagnosis of chronic fetal hypoxia during cardiotocographic examination, a comprehensive assessment of the parameters of the fetal heartbeat is carried out, expressed from 0 to 5 points. The lower the score, the worse the condition of the fetus due to hypoxia.

The disadvantage of this method is the low accuracy of diagnosis of chronic fetal hypoxia in the early stages due to the good compensatory capabilities of the fetal cardiovascular system.

There is a method of evaluating the resistance of the fetus to hypoxia by recording the time from the beginning of the breath holding of the pregnant woman to the respiratory excursion of the ribs of the fetus (Urakova N.A., Gausknecht M.Yu. Fetal hypoxia: new diagnostic possibilities. Status Praesens. - 2012. - No. 3 (9 ). - S. 70-73).

In the known method for the diagnosis of chronic fetal hypoxia during an ultrasound examination of the fetoplacental complex, the time from the beginning of the holding of a pregnant breath to the respiratory excursion of the chest of the fetus is determined, and if the time is less than 15 seconds, the test result is interpreted as “reduced fetal resistance to hypoxia”.

The disadvantage of this method is the low information content due to the lack of consideration of other factors, in addition to hypoxia, affecting the motor activity of the fetus, including during the physiological course of gestation.

A known method for the diagnosis of chronic fetal hypoxia by analyzing the heart rate variability of a pregnant woman (Piskunova L.V., Chekhonatskaya M.L., Arenina N.Yu. Diagnostic and prognostic value of the analysis of heart rate variability of a pregnant woman in assessing the severity of fetal hypoxia. Saratov Journal of Scientific and Medical Journal . - 2010. - No. 3 (6). - S. 540-543).

In the known method for the diagnosis of chronic fetal hypoxia, with an increase in the tone of the sympathetic section of the autonomic nervous system, chronic fetal hypoxia is diagnosed.

The disadvantage of this method is the indirect relationship between the variability of the heart rhythm of the mother and the development of intrauterine hypoxia, which leads to low information content of this method for the diagnosis of chronic hypoxia of the fetus.

Closest to the claimed is a method for the diagnosis of chronic fetal hypoxia by ultrasonic Dopplerographic estimation of blood flow velocity curves in the middle cerebral artery of the fetus during a test with a pregnant woman holding her breath (Smolyaninov G.V., Orlov A.V. Complex diagnostics of hypoxic lesions of the fetal brain. Russian Bulletin obstetrician-gynecologist. - 2008. - No. 3. - S. 15-17).

In this method for the diagnosis of chronic fetal hypoxia, ultrasound Doppler blood flow in the middle cerebral artery of the fetus is performed before and after holding the breath of a pregnant woman. With an increase in the indices of resistance indices in the middle cerebral artery of the fetus after a pregnant woman holds her breath, indicating a reaction, with cerebral ischemia, the middle cerebral artery of the fetus on maternal apnea in the form of spasm, chronic fetal hypoxia is diagnosed.

The disadvantage of this, closest to the claimed method is the low accuracy of diagnosis of chronic fetal hypoxia due to the lack of information of a single, without taking into account temporary fluctuations in daily rhythmostasis, measurements of functional indicators.

The problem solved by the invention is the diagnosis of chronic fetal hypoxia.

The technical result is to increase the accuracy of diagnosis. The specified technical result is achieved by the fact that in the method for diagnosing chronic intrauterine hypoxia, the fetus is examined by ultrasound Dopplerography of the blood flow in the middle cerebral artery before and after the maximum possible breath holding of the pregnant woman with a deep breath and this examination is additionally carried out taking into account the fetal rhythmostasis at 12:00 and 20:00 hours when the diagnostically significant minimum and maximum values of the resistance indices of the curves of blood flow velocity curves in the mean traction artery fetus. With an increase in the indices of peripheral resistance: systolic-diastolic ratio, resistance index, pulsation index of blood flow velocity curves in the middle cerebral artery of the fetus after holding the breath compared to the initial ones, before holding the breath, the values of the ultrasound dopplerography performed at 12:00 and 20:00 are diagnosed chronic fetal hypoxia.

A method for diagnosing chronic fetal hypoxia is as follows.

The pregnant woman and the fetus are examined taking into account the diurnal rhythmostasis of the peripheral resistance indices of the peripheral resistance curves of the blood flow velocities in the middle cerebral artery of the fetus, which was revealed for the physiological and complicated by chronic hypoxia of the fetus: at 12:00 and 20:00 ultrasound dopplerography of the blood flow in the middle cerebral artery of the fetus with a quantitative assessment of systole diastolic ratio, resistance index, pulsation index before and after the maximum breath-holding of a pregnant woman at deep airway ooh.

With physiological and complicated by chronic hypoxia of the fetus of pregnancy, the above parameters have the following meanings.

In the physiological course of the third trimester of pregnancy, the indices of peripheral resistance indices of the blood flow velocity curves in the middle cerebral artery of the fetus during a breath-holding test, obtained using ultrasound dopplerography on an Acuson Simens apparatus (Germany), have the following quantitative characteristics:

- systolic-diastolic ratio

at 12.00 hours before breath holding 3.86 ± 0.06,

after holding the breath 3.45 ± 0.07 and

at 20.00 hours before breath holding 3.65 ± 0.06,

after breath holding 3.39 ± 0.05;

- resistance index

at 12.00 hours before breath holding 0.77 ± 0.04,

after holding the breath 0.63 ± 0.05 and

at 20.00 hours before breath holding 0.72 ± 0.03,

after holding the breath 0.61 ± 0.04;

- ripple index

at 12.00 hours before the breath holding 1.82 ± 0.03,

after holding the breath 1.73 ± 0.04 and

at 20.00 hours before holding the breath 1.76 ± 0.03,

after holding the breath 1.61 ± 0.05.

For fetal chronic hypoxia in the third trimester of pregnancy, the following indices of peripheral resistance of the blood flow velocity curves in the middle cerebral artery of the fetus during a breath-holding test are characteristic:

- systolic-diastolic ratio

at 12.00 hours before breath holding 3.71 ± 0.05,

after breath holding 4.56 ± 0.08 and

at 20.00 hours before holding the breath 3.92 ± 0.06,

after holding the breath 4.74 ± 0.09;

- resistance index

at 12.00 hours before breath holding 0.69 ± 0.03,

after holding the breath 0.87 ± 0.04 and

at 20.00 hours until breath holding 0.80 ± 0.03,

after breath holding 0.91 ± 0.04;

- ripple index

at 12.00 hours before breath holding 1.78 ± 0.04,

after holding the breath 1.92 ± 0.03 and

at 20.00 hours before holding the breath 1.84 ± 0.04,

after holding the breath 1.97 ± 0.04.

Example. Pregnant K., 32 years old, was in antenatal hospitalization at the Department of Pregnancy Pathology, City Clinical Hospital No. 2 named after ON. Semashko with a diagnosis of:

Pregnancy I, 39 weeks.

Head presentation.

Nulliparous older.

Chronic placental insufficiency, compensated form.

Chronic pyelonephritis in remission.

A "ripening" cervix.

From the anamnesis: in childhood, she suffered from rubella, mumps, chickenpox; SARS is sick annually. Chronic pyelonephritis from 28 years of age, inpatient treatment due to exacerbation of the disease - once at 28 years. Menstrual function without features. Gynecological diseases: candidal colpitis treated three years ago. The husband is healthy. I got into the dispensary registration in connection with pregnancy for a period of 8 weeks of gestation. The antenatal clinic was observed regularly. The first half of pregnancy was uneventful. The diagnosis of “compensated chronic placental insufficiency” was made at 36 weeks of gestation according to an ultrasound examination of the fetoplacental complex. Examination results at 36 weeks: CTG - without features, UZDG - uterine-placental and fetal-placental blood flows are normal. She received 1200 mg per day os diosmin treatment for two weeks. A comprehensive examination was carried out in the department of pregnancy pathology to develop obstetric tactics by the timing and method of delivery. Survey results: ultrasound examination of the fetoplacental complex - without features, CTG - no fetal distress, UZDG - uterine-placental and fetal-placental blood flow are normal. The results of a single, without taking into account daily rhythmostasis, dopplerographic examination with determination of the resistance indices of the blood flow velocity curves in the middle cerebral artery of the fetus during the test with breath holding: systolic-diastolic ratio before holding the breath 3.84, after holding the breath 3.48; resistance index before breath holding 0.79, after holding the breath 0.66; the pulsation index before breath holding 1.84, after holding the breath 1.75 - deviations from the standards characteristic of physiological gestation were not detected. Given that the pregnant woman belongs to the high-risk group for impaired fetal condition, it was decided to conduct an ultrasound Dopplerographic examination of the blood flow in the middle cerebral artery of the fetus according to the developed method for the diagnosis of chronic fetal hypoxia. Survey results: systolic-diastolic ratio at 12.00 hours before holding the breath 3.73, after holding the breath 4.59 and at 20.00 hours before holding the breath 3.95, after holding the breath 4.81; resistance index at 12.00 hours before holding the breath 0.71, after holding the breath 0.90 and at 20.00 hours holding the breath 0.82, after holding the breath 0.94; the pulsation index is at 12.00 hours before holding the breath 1.81, after holding the breath 1.94 and at 20.00 hours holding the breath 1.87, after holding the breath 1.98.

Analysis of the results of the survey on the proposed method for the diagnosis of chronic fetal hypoxia showed an increase in all three resistance indices of the blood flow velocity curves in the middle cerebral artery of the fetus during examination both at 12.00 hours - the time of the minimum daily values of these indicators, and at 20.00 - the time of the maximum daily values of these indicators . Based on the results of the examination, a diagnosis of chronic fetal hypoxia was made. Considering that pregnant K. is a primiparous older with extragenital pathology and belongs to the high risk group for perinatal mortality, a careful method of delivery by cesarean section was chosen. The operation went without features. A full-term girl was born with an Apgar score of 1 minute - 6 points, 5 minutes - 7 points (mild asphyxiation), body weight 2900 grams, long body - 52 cm. Determination of the gas composition of the blood of a newborn child confirmed the state of mild asphyxia at birth. In the period of early adaptation, manifestations of conjugated jaundice were noted. The postpartum period in the mother proceeded without complications. The postpartum woman and the newborn were discharged home on the 6th day after delivery in a satisfactory condition. The result of a histological examination of the placenta: placental insufficiency of the II degree of severity.

The conclusion of this example: this clinical example demonstrates the diagnostic capabilities of the proposed method for the diagnosis of chronic fetal hypoxia. When examining pregnant K. high-risk group for violation of the fetus using single measurements (ultrasound, CT, ultrasound) characterizing the status of the placental complex, there was no change in the functional state of the fetus. Examination according to this method for the diagnosis of chronic fetal hypoxia using ultrasound Dopplerography of blood flow in the middle cerebral artery of the fetus during a breath-holding test, taking into account the fetal rhythmostasis at 12.00 and at 20.00, when diagnostically significant minimum and maximum values of the resistance indices of the curves of blood flow velocity curves are detected in the middle cerebral artery of the fetus, revealed chronic fetal hypoxia and gently deliver a woman with favorable perinatal outcome.

Analysis of the effectiveness of the proposed method for the diagnosis of chronic fetal hypoxia was carried out in a randomized study of 424 pregnant women at high risk for severe forms of chronic placental insufficiency. The control group consisted of 42 pregnant women with a physiological course of gestation and normal fetal development. Of 424 pregnant women at high risk for severe forms of chronic placental insufficiency, 208 pregnant women were diagnosed with chronic fetal hypoxia by measuring ultrasound dopplerography of blood flow velocity curves in the middle cerebral artery of the fetus, and 216 pregnant women were examined in accordance with the rules of the International Society of Chronobiologists ( 1995). According to the results of mathematical processing of chronograms (216 pregnant high-risk groups and 42 pregnant women with physiological gestation), according to F.I. Komarov et al. (2000), biorhythms of indices of resistance indices of blood flow velocity curves in the middle cerebral artery of the fetus (systolic-diastolic ratio, resistance index, pulsation index) were identified acrophase - the time of the highest value of the indicator, and bathyphase - the time of the lowest value of the indicator for the studied parameters characterizing blood flow in the middle cerebral artery of the fetus. In the physiological course of pregnancy and the normal state of the fetus, the acrophase corresponded to 12.00 hours, the bathyphase corresponded to 20.00 hours for all three fixed indices of peripheral resistance. In chronic fetal hypoxia, the acrophase of the resistance indices of the blood flow velocity curves in the middle cerebral artery of the fetus, on the contrary, corresponded to 20.00 hours, and the bathyphase - 12.00 hours. Of the 216 pregnant women at high risk for severe forms of chronic placental insufficiency, 78 (36.1%) in the period 34-39 weeks of pregnancy were diagnosed with chronic fetal hypoxia according to this method (main group). Of 208 pregnant women at high risk for severe forms of chronic placental insufficiency, in which intrauterine hypoxia was diagnosed by single measurements of ultrasound dopplerography, a diagnosis of chronic fetal hypoxia was made in 43 (20.7%) - comparison group. All pregnant women with a diagnosis of “chronic fetal hypoxia” were delivered by caesarean section. The Apgar score for 1 and 5 minutes of life in newborns with diagnosed chronic fetal hypoxia during pregnancy by the proposed method (main group) was 6.1 ± 0.35 points and 6.9 ± 0.44 points, respectively, in newborns with diagnosed with chronic fetal hypoxia during pregnancy by single measurements of ultrasound dopplerography indicators (comparison group) - 7.8 ± 0.26 points and 8.0 ± 0.29 points, respectively, in the control group - 8.1 ± 0.21 points and 8.5 ± 0.32 points, respectively. The state of asphyxia was confirmed by determining the gas composition of the blood (determination of blood pH from the umbilical artery taken before the first breath of the newborn, less than 7.18 indicates hypoxemia). A correlation analysis between the Apgar score and the pH of arterial blood taken before the first breath in the group of women examined taking into account the fetal circadian rhythmostasis showed a strong positive correlation (k = 0.96), which indicates the correct diagnosis of “chronic hypoxia” fetus ”by the proposed method in the vast majority of observations. In this (main) clinical group, perinatal mortality and severe complications of the early neonatal period were absent, due to the timely diagnosis of chronic fetal hypoxia and adequate obstetric tactics. In the group of women with single measurements, a similar correlation analysis showed a weak positive correlation (k = 0.39), which indicates that the diagnostic method for diagnosing chronic fetal hypoxia is insufficiently informative, using single measurements of ultrasound Dopplerography of the blood flow velocity curves in the middle cerebral artery of the fetus.

Based on the verification of the diagnosis of “chronic fetal hypoxia”, confirmed by the gas composition of the blood at birth and the clinical evaluation of newborns in the early adaptation period, the sensitivity, specificity, accuracy, and prognostic value of the positive and negative results of this method for diagnosing chronic fetal hypoxia during pregnancy, which are respectively 91%, 87%, 90%, 92% and 94%, which indicates high information content and reliability of the proposal the proposed diagnostic method.

Thus, the use of a dopplerographic assessment of blood flow velocity curves in the middle cerebral artery of the fetus for the diagnosis of chronic fetal hypoxia, taking into account its daily rhythmostasis, significantly expands the diagnostic capabilities of the method, allows timely detection of deviations from the physiological state of the fetus, and the development of optimal obstetric tactics. The reduced accuracy of the diagnosis of chronic fetal hypoxia by evaluating the blood flow velocity curves in the middle cerebral artery of the fetus without taking into account its daily rhythmostasis is due to the fact that this does not take into account diagnostically significant indicators of blood flow velocity, which can be recorded against the background of fluctuations in the daily biological rhythms of the mother-placenta functional system -fetus".

The rhythmometry of the resistance indices of the blood flow velocity curves in the middle cerebral artery of the fetus provides a timely opportunity to judge the intrauterine condition of the fetus, the presence or absence of chronic intrauterine hypoxia; can be used to monitor the effectiveness of the treatment of chronic fetal hypoxia.

A change in the indicators proposed to characterize the condition of the fetus indicates a breakdown in the adaptive capabilities of the fetus and the need for their intensive correction up to early delivery.

The positive effect of the proposed diagnostic method is a fundamentally new opportunity for the timely diagnosis of chronic fetal hypoxia due to the assessment of previously unused parameters. The method is non-invasive, safe for the health of the pregnant woman and the fetus, widely available for modern obstetric institutions.

At the filing date, the applicants did not find a diagnostic method with the claimed combination of features, as a result of which we conclude that the claimed technical solution meets the criteria of the invention of “novelty”.

According to the results of a comparative analysis, the totality of the features of the proposed diagnostic method provides it with new properties in the form of increasing the accuracy of diagnosis, that is, according to the applicants, the proposed method meets the criterion of "inventive step".

The criteria of the invention "industrial applicability" is confirmed by the fact that the inventive diagnostic method can be successfully applied in mass examinations of pregnant women and their fetuses as screening with the identification of accurate and early signs of fetal hypoxia.

Claims (1)

A method for diagnosing chronic fetal hypoxia, including determining the indices of resistance indices of blood flow velocity curves in the middle cerebral artery of the fetus during ultrasound dopplerography before and after the maximum possible breath holding of a pregnant woman at a depth of inspiration, followed by analysis of the data, characterized in that diagnostically significant indices of resistance indices of the curves are determined blood flow velocities in the middle cerebral artery of the fetus - systolic-diastolic ratio, resistance index, bullets Sation index during the test with breath holding taking into account the fetal circadian rhythmostasis, and with the values of Dopplerography: systolic-diastolic ratio at 12.00 hours before holding the breath 3.71 ± 0.05, after holding the breath 4.56 ± 0.08 and 20.00 hours before holding the breath 3.92 ± 0.06; after holding the breath 4.74 ± 0.09; the resistance index at 12.00 hours before holding the breath 0.69 ± 0.03, after holding the breath 0.87 ± 0.04 and at 20.00 hours before holding the breath 0.80 ± 0.03, after holding the breath 0.91 ± 0, 04; the pulsation index at 12.00 hours before holding the breath 1.78 ± 0.04, after holding the breath 1.92 ± 0.03 and at 20.00 hours before holding the breath 1.84 ± 0.04, after holding the breath 1.97 ± 0, 04, detect a change in the functional state of the fetus and diagnose chronic fetal hypoxia.