Infantile bradycardia describes a slow heart rate of below 100 beats per minute in an infant, often a premature infant.
In premature infants, the bradycardia is often accompanied by pauses in breathing or apnea.
This break in breathing may occur for 20 seconds or more and cause the baby to gasp, gag, or even turn pale or blue.
Infants usually have bradycardia for the same reasons they have apnea, which is most commonly seen in premature infants.
In babies born before term, the nervous system has not finished developing and the respiratory center in the brain, that instructs the lungs to inhale, may not be fully functional.
About 45% of babies with a birthweight of less than 5.5 pounds will have at least some degree of apnea and about 85% of those weighing less than 2.5 pounds at birth will have sleep apnea.
However, other medical problems can sometimes be the cause of apnea, especially if the baby is full-term. Examples of these other factors include:
- Infection, meningitis or pneumonia
- Low blood sugar
- Temperature instability
- Hypoxia (insufficient blood oxygen)
- Seizure or convulsion
- Mechanical obstruction of the airways
- Necrotizing enterocolitis
- Intracranial hemorrhage or bleeding within the brain
- Hydrocephalus or fluid accumulation in the brain
- Patent ductus arteriosus (a form of patency or hole in the heart)
- Atelectasis or collapsed lung
- Gastroesophageal reflux
- Maternal drug addiction and withdrawal symptoms
- Congenital hypoventilation syndrome
Certain drugs such as caffeine and theophylline may be used to stimulate breathing and correct the heart rate.
Gentle stroking or tickling of the feet may also stimulate breathing.
Mechanical ventilation using a breathing machine or CPAP (continuous positive airways pressure) may also prevent apnea and bradycardia.
Reviewed by Sally Robertson, BSc