Cardiotocography, auscultation of cardiac activity, staining of amniotic fluid
Last reviewed: 23.04.2024
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In the process of normal delivery in the fetal physiological state a gradual increase in the frequency of meconium in the amniotic fluid occurs, but there are no significant differences between the groups.
Auscultation of cardiac fetal activity with an obstetrical stethoscope was performed at each parturient in the process of birth at least once a hour in the first period and after every attempt in the second stage of labor. The results of the determination of auscultatory fetal heart rate at physiological births indicate the stability of the studied parameter and even in the II period the average fetal heart rate does not significantly differ from single-valued indices in other groups. The auscultatory fetal heart rate was in the 1 st group - (135.1 ± 0.31) bpm; in the second - (135.9 ± 0.45); in the third - (135.3 ± 0.67); in the 4th - (137.7 ± 0.53); in the 5th - (137.2 ± 0.83); in the 6th group - (136.9 ± 0.4) bpm.
Cardiotocography, being a safe and accessible method, found wide application in obstetrical practice for the diagnosis of fetal status and in this study was performed at all births at least 3 times during childbirth.
The results of cardiotocography show that in the process of physiological births, the average heart rate is within the normal range and practically does not differ from the auscultation data. Changes in heart rate during the first stage of labor do not differ significantly between groups.
The index of decrease in intramuscular fluctuations in the process of opening the uterine pharynx gradually increases, although there are no significant differences between the groups in the course of the mathematical analysis, and a tendency to increase of the trait is traced. Similar changes occur with the index of the myocardial reflex. At the same time, myocardial reflex and deceleration indices less often indicate fetal suffering in the absence of hypoxia than intra-minute fluctuations. The increase in the amount of decleration in the 4th group significantly differs from those of the 3rd group. Between the 2 nd and 3 rd groups there were no significant differences.
Thus, despite the physiological condition of the fetus, CTG data in some cases indicated its intrauterine suffering. Obviously, we should agree with L. Lampe, who believes that changes in cardiac activity are related to the group of functional signs of asphyxia and the assessment of fetal status based on them is possible only under certain conditions and requires a critical analysis.
The prognostic value of changes in fetal heart rate can be summarized as follows:
- in most cases, these changes precede the formation of fetal acidosis, so they should be considered as early warning signs:
- the CTG constant makes it easier to recognize typical deviations;
- continuity of registration is the main requirement, since experience shows that even with severe acidosis, the fetal heart rate remains normal for a long time;
- even with the continuous recording of heartbeats and the recognition of characteristic changes, the degree of fetal hypoxia can not be quantified.
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