Bradycardia of the newborn: causes, signs, treatments

Bradycardia or brachycardia consists of a reduction in heart rate to a level below (in adults) 60 beats per minute.

It is a disorder that quite often occurs in adults, especially in old age, but it is not rare even in newborns.

In this second case, bradycardic is defined as that heart rhythm of the newborn having a frequency lower than at least 30 beats/min with respect to the frequency of 100 beats/min considered normal in newborns. Bradycardia can occur

  1. either in the absence of a well-defined cause and may not even lead to any health problems,
  2. either (as also in the case of other types of arrhythmias) following an electrical anomaly concerning the heart muscle;
  3. either after taking certain medications,
  4. but also as a consequence of some pathologies.

Although it can sometimes be a symptom of a specific pathology, brachycardia in the newborn usually affects babies born prematurely. It is very important not to underestimate it in any case, and try to identify the causes in order to establish the relative treatment.

Especially in newborns from a premature birth, bradycardia is often accompanied by a state of apnea which can even last a few tens of seconds, causing in the baby:

  • of respiratory crises,
  • hypoxia (a lack of oxygen in the body),
  • a cyanosis.

If symptoms of this type should occur, it is advisable to consult your pediatrician immediately.

However, it must be taken into account that in most cases, neonatal bradycardia is not linked to any pathological condition, but is simply due to premature birth.

Signs of bradycardia in the newborn

As we have said, if we take into account that the normal heart rate of the newborn in this phase of his life is about 100 beats/min, we are in the presence of bradycardia in the case of a slowdown in heart rate of at least 30 beats /min.

The signs/symptoms of the bradycardia rhythm of the newborn are completely similar to those of the adult, and refer above all to the lack of correct oxygenation of his body which entails for the child,

  • a feeling of discomfort,
  • sleep disorders,
  • dizziness,
  • chest pains,
  • confusional state.

Obviously, such a young subject is not able to express himself or describe his discomfort and, for this reason, a correct diagnosis can initially be difficult.

Without taking into account that neonatal bradycardia is often completely asymptomatic and therefore cannot be detected without medical supervision.

To prevent bradycardia in the newborn, regular visits to a pediatrician are important. He normally evaluates the conditions of the respiratory tract in order to make sure that the newborn has correct spontaneous ventilation. Through these periodic checks, he is able to identify the existence of any cardiac disturbances and, when he deems it necessary, he can submit the child to the tests necessary to discover the causes.

Its most frequent causes

As we have said, bradycardia in newborns is linked in many cases to a premature birth, and therefore it is often a situation that is not linked to any pathology. In fact, being born ahead of schedule, the baby’s cardio-respiratory system may not yet be fully completed, thus causing a series of problems, including poor oxygenation, with consequent slowing of the heart rate.

In these cases, the younger the baby and the more prematurely it was born, the higher the chances of bradycardia and apnea episodes occurring.

However, premature birth is not the only cause of bradycardia in newborns. It could in fact be due to particular physical conditions, to some pathologies, to other disorders. It could be due, just to name a few,

  • to gastric reflux,
  • to lung problems,
  • to current infections,
  • to a lack of sugars,
  • to thyroid dysfunction,
  • to anomalies of thermoregulation.

Even the intake of some drugs by the mother, in particular beta-blockers, can cause bradycardia in the newborn.

This problem often occurs in children who have had open heart surgery.

To know exactly the reasons that have caused bradycardia in a newborn, as we have said, it is necessary to consult your trusted pediatrician, who will submit the baby to a series of tests and clinical checks.

How it is treated

In order to correctly diagnose bradycardia, the baby must undergo a cardiological visit, an electrocardiogram and, if deemed appropriate, the application of a holter.

Very often this is simply a transient anomaly, and the heart rate tends to stabilize on its own within a few days.

If, on the other hand, the baby shows signs of respiratory distress with a heart rate that is always too low, it may be necessary to resort to artificial ventilation using a face mask: if this proves to be ineffective, with intubation.

If, despite ventilation and intubation, the frequency should remain particularly low, a series of chest compressions should be performed and doses of adrenaline administered intravenously.

In the event that bradycardia causes total blockage of the heart, the use of a pacemaker may be necessary.

Bradycardia of the fetus: what can it be due to?

The heart rate of the fetus is around 110/160 beats per minute. A lower value is referred to as fetal bradycardia, which may or may not be related to hypoxia.

When fetal bradycardia is not of hypoxic origin, the most common causes are usually a heart defect in the baby, or a particular drug therapy followed by the mother. Very often fetal bradycardia,

  • is due to a not particularly worrying cause,
  • the fetus does not show signs of discomfort or suffering or particular anomalies,
  • so much so that caesarean delivery is only rarely necessary.

Katherine Johnson, M.D., is a board-certified obstetrician-gynecologist with clinical expertise in general obstetrics and gynecology, family planning, women’s health, and gynecology.

She is affiliated with the Obstetrics and Gynecology division at an undisclosed healthcare institution and the online platform,

Leave a Reply

Your email address will not be published. Required fields are marked *