What is Neonatal Asphyxia?
Newborn asphyxia is a pathological condition of newly born children, in which the baby’s breathing is disturbed, and oxygen deficiency develops. This condition threatens the life and full development of the child. Asphyxia may occur during childbirth or in the first few days after birth.
Asphyxiation in modern medicine can be divided into moderate (moderate) and severe. The division is on the Apgar scale, which will be described in detail below.
Causes of Newborn Asphyxia
Asphyxia can not be causeless. It is divided by origin into primary and secondary. Primary appears in the process of childbirth. It is caused by acute or chronic intrauterine hypoxia of the fetus. Also among the possible causes are:
- malformations of the fetus, which are reflected in his breathing, making breathing difficult;
- intracranial injury in a child that he receives during childbirth;
- obstruction of the baby’s respiratory tract with amniotic fluid or mucus;
- immunological incompatibility of mother and fetus.
With extragenital diseases, a pregnant woman may experience signs of primary asphyxiation in the fetus. For example, a child may suffer from diabetes, heart and blood vessel diseases, and iron deficiency anemia in his mother. With late toxicosis (or gestosis) in a mother with high blood pressure and swelling of the hands and feet, the child is likely to have a lack of oxygen.
The causes of asphyxia of newborns can be hidden in the pathological morphology of the umbilical cord, placenta, membranes surrounding the fetus. Among the risk factors, early placental abruption and other causes, which are described in detail in the article Hypoxia of the fetus, are most relevant.
Typical causes of secondary asphyxia in newborns:
- cerebrovascular accident in a newborn;
- heart defects;
- damage to the central nervous system.
Secondary asphyxia can be caused by pneumopathies:
- hyaline membranes;
- edematous hemorrhagic syndrome;
- lung hemorrhage;
- polysegmental atelectases;
- scattered atelectasis.
They can develop both during the baby’s stay in the mother’s stomach, and during childbirth. With them, the development of respiratory distress syndrome occurs.
Pathogenesis during Asphyxia of the Newborn
Regardless of what the cause of asphyxiation of the newborn was, there is a restructuring of metabolic processes, hemodynamics and microcirculation. The extent to which they are expressed depends on the duration of the lack of air. Metabolic acidosis develops, which goes away with azotemia, hypoglycemia, hyperkalemia, which then evolves into a lack of potassium.
The result of the described processes is cell hyperhydration. The volume of circulating blood increases due to an increase in the volume of circulating red blood cells. With asphyxia, which developed against a background of chronic fetal hypoxia, hypovolemia occurs. Blood thickens, blood viscosity increases, and the aggregation ability of red blood cells and platelets increases.
As a result of microcirculation disorders in the heart, brain, kidneys, liver and adrenal glands, edema appears, as well as areas of ischemia, hemorrhage, tissue hypoxia. There is a violation of the peripheral and central dynamics of the blood, therefore, the stroke and minute volume of the heart is reduced. Blood pressure is getting lower. urinary function of the kidneys is impaired.
Symptoms of Asphyxia of the Newborn
As already noted, the severity of hypoxia and asphyxia of the newborn is measured on the Apgar scale.
Symptoms of moderate asphyxia of the newborn:
- lethargy at birth
- condition can be assessed as moderate
- poor response to examination and irritants
- spontaneous physical activity
- almost no emotion scream, short in duration
- physiological reflexes are weak
- spontaneous reflex Moro
- skin cyanosis
- with oxygenation, the skin quickly turns pink (but acrocyanosis may remain)
- fine hand tremor
- hyper excitability
- positive symptom ilpo
- too much spitting up
Auscultatory methods with moderate asphyxia make it possible to identify muffled heart sounds or their increased sonority, tachycardia. Breathing after prolonged apnea is rhythmic, with sighs. There is a chance of repeated apnea. Over the lungs, the doctor can fix wet rales, weakened breathing, boxed percussion tone.
The violations listed above, as doctors put it, are functional in nature. That is, they manifest themselves with metabolic disorders and intracranial hypertension, with proper timely treatment, they will pass, the child’s condition will become normal on the fifth day of life.
Symptoms of severe asphyxia of the newborn:
- at birth, the child is in a serious or very serious condition
- physiological reflexes are practically reduced to zero
- active oxygenation in most cases causes a pinkish tint to the skin of the baby
- deafness of heart sounds
- probable systolic murmur
- hypoxic shock is likely (pallor of the skin with an earthy tint, no spontaneous breathing, no reaction to pain, eyes closed, etc.)
In the worst case, the child has impaired functioning of many organs and systems. May be myosis or mydriasis. Pupils do not react to light. Areflexia and muscle atony are observed.
Complications of Asphyxia in Children
A group of early complications is observed in the first few hours of life (up to 24 hours):
- intracranial hemorrhage
- cerebral edema
- brain necrosis
- periventricular lesions
- pulmonary hypertension
- acute tubular renal necrosis
- myocardial ischemia
- surfactant synthesis deficiency
- renal vascular thrombosis
- hydrocephalic syndrome
- pneumonia, etc.
Diagnosis of Asphyxia of the Newborn
Asphyxia is not difficult to determine. It is recognized by breathing disorders in the very first minutes after birth, by heart rate, reflexes, muscle tone, and shade of the skin of the baby. Indicators of the acid-base state also indicate the severity of the disease. Normally, the pH of the blood from the umbilical vein is in the range of 7.22-7.36 BE, the base deficit is from -9 to -12 mmol / l. These indicators with asphyxia of light and medium reach 7.19-7.11 and from – 13 to – 18 mmol / l. With severe asphyxia of the newborn, a pH of less than 7.1 BE from – 19 mmol / l or more.
Hypoxic from traumatic damage to the nervous system can be distinguished by a neurological examination of a recently born child and an ultrasound of the brain. If the lesion is mainly hypoxic, then focal neurological symptoms are not manifested, there is a development of a syndrome of increased neuro-reflex excitability. In severe form, there is a syndrome of depression of the central nervous system.
With the traumatic nature of the lesion with extensive ventricular and other hemorrhages after birth, hypoxemic vascular shock with a spasm of peripheral vessels is detected. The diagnosis is made on the basis of such manifestations as hyper-excitability, pallor of the skin, convulsive syndrome 2-4 hours after delivery, focal neurological symptoms, etc.
A differential diagnosis should be made with acute blood loss, conditions that cause cardiorespiratory depression, respiratory distress syndrome, and intracranial hemorrhage.
Treatment of Asphyxia of the Newborn
In the United States, a system of primary resuscitation of newborns was developed. Its stages are called ABC steps. Step A – Ensure airway. B – stimulate or restore breathing. Step C – maintain the baby’s blood circulation. After his birth, it is necessary to establish whether or not meconium is present in the amniotic fluid, the nature of further resuscitation measures depends on this.
If meconium is not present in the amniotic fluid, take the following steps:
- carry the baby under an infrared heater
- soaking his skin through the diaper with wetting movements, the wet diaper is thrown away
- provide the greatest airway: a child is placed on his back, his head is moderately unbent, a roller is placed under his shoulders
- the baby’s nasopharynx and mouth are cleaned of contents, without touching the back of the throat, so as not to provoke bradycardia and apnea through excitation of the parasympathetic nervous system
- if there is no spontaneous breathing, tactile stimulation is performed (easily clap on the heel, on the sole, rub the skin with the palm of your hand along the line of the spine)
What can not be done with a child with asphyxiation:
- give a stream of oxygen to the face
- splash or pour cold / hot water
- clap buttocks
- compress the chest
If meconium is detected in the amniotic fluid (there is meconium aspiration), it should:
- from the upper respiratory tract after the birth of the head, the contents should be sucked
- place your baby under a radiant heat source
- do not dry the baby, but lay on the back so that the head is slightly tilted back and there is a roller under the shoulders
- intubate the trachea
- repeatedly remove with suction everything that is in the upper respiratory tract of the baby
The contents of the trachea tree are aspirated without a catheter using an endotracheal tube. If it contains meconium residues, then intubation and suction should be repeated. The events listed above are held in 20 seconds. After this, you need to evaluate three signs of the condition of the newborn:
- skin tone
If spontaneous breathing is not present or it is too small, then they carry out artificial ventilation of the lungs with 90-100% oxygen – a mask and Ambu bag are used. Respiratory rate 40 / min., Pressure 20-40 cm water column. If mechanical ventilation is performed for a duration of 2 minutes or more, a probe is inserted into the stomach to decompress and prevent regurgitation. In the absence of the effect of mask ventilation, endotracheal intubation is performed and ventilation is continued.
Probe Insertion Procedure
The probe is inserted to a depth equal to the distance from the nose to the earlobe and from the earlobe to the epigastric region. After that, the gas is aspirated by a syringe from the stomach, the probe is left open and fixed with an adhesive plaster to the cheek. Artificial ventilation continues over the probe. After 15-30 seconds, you need to assess the condition of the newborn, measure the heart rate in 6 seconds and multiply by 10. During the counting period, ventilation must be stopped.
If the heart rate is 100 or more, see if there is spontaneous breathing. If so, they evaluate skin tone by stopping ventilation. With a heart rate of 60-100 and an increasing frequency, you need to continue to artificially ventilate the lungs. With a heart rate of 60-100 and a non-increasing frequency, an indirect heart massage is performed (with a heart rate of 80 or less). With a heart rate of less than 60, an indoor heart massage and mechanical ventilation are performed. Heart rate monitoring is carried out after 10-15 seconds until the frequency is more than 100, and until spontaneous respiration is restored.
In order to resuscitate with asphyxia of the newborn, an indoor heart massage is performed if heart beats per minute are 60-80 without progress. Tracheal intubation is effective. Among resuscitation drugs, a 0.01% solution of adrenaline in a dose of 0.1-0.3 mg / kg is effective. It is administered intravenously or endotracheally quickly. Recovering the volume deficit is carried out using a 0.9% solution of sodium chloride, 5% albumin, the dose is 10 ml per 1 kg of the baby’s body. Intravenous administration should take 5 to 10 minutes.
Sodium bicarbonate (4.2% solution) is administered to the baby at a dose of 2-4 ml / kg. A 0.05% solution of nalorfin is administered intravenously quickly or subcutaneously at a dosage of 0.1-0.2 ml per 1 kg of the child’s body. A 0.5% dopamine solution is administered at a dose of 5-20 mct / kg / min intravenously. In this case, control of blood pressure and heart rate is important.
If necessary, begin routine infusion therapy at the 40-50th minute of the baby’s birth. On the first day, the volume should be 60-65 ml / kg / 24 hours in the form of an isotonic Ringer’s solution, a solution of sodium chloride, reopoliglyukin.
Prognosis for Asphyxia of the Newborn
Children born on time, with severe asphyxia, die in 10-20 cases out of 100, they have a high frequency of deviations from the neuropsychiatric system. The prognosis is worsened by the preservation of very low (3 points or less) ratings on the Apgar scale 15 and 20 minutes after birth, the presence of posthypoxic encephalopathy of 1 and 2 degrees and other complications.
Baby care after fetal asphyxiation
After asphyxia, proper child care is important. He is provided with the need to ensure complete peace. Its head should be in a raised position. Doctors often prescribe oxygen therapy. After a mild form of asphyxiation, infants are placed in a special tent with a high oxygen content. The time spent in it is individual in each case.
After asphyxiation of a severe or moderate form, the child must be placed in a couvez where oxygen is supplied. If there is no special equipment, nasal cannulas or breathing masks are used. The newborn after any asphyxiation is observed. Need control diuresis, bowel function, body temperature. When a child is undergoing mild or moderate asphyxia, it should be fed no earlier than 16 hours after birth.
Prevention of Asphyxia of the Newborn
Prevention of newborn asphyxiation helps to avoid many critical conditions and complications. Among the risk factors are called:
- age from 35 years
- infectious and somatic diseases of the pregnant
- hormonal changes
- endocrine disruption
- stressful situations
- bad habits
Intrauterine monitoring of the state of the placenta and the fetus should be carried out. It is needed for the timely detection of various violations. A pregnant woman should visit a gynecologist regularly. Long, relaxing walks in the fresh air are recommended.
Among the effective preventive measures are:
- daily routine
- enough rest
- taking vitamins and minerals as directed by a doctor
- maintaining a positive mood and calm in any situation
- communication with positive people
- rejection of bad habits of the expectant mother and her environment