Sudden Infant Death Syndrome

– The sudden, unexplained death of an infant under 1 year of age that remains unexplained after a complete postmortem examination.

Causes and Incidence

The cause of sudden infant death syndrome (SIDS) is unknown. One widely accepted hypothesis is that it is related to a brainstem abnormality in the neurologic regulation of cardiorespiratory control. Risk factors include prematurity, multiple births, low Apgar scores, central nervous system or respiratory disturbances, poverty, prone sleeping position, overheating, and maternal smoking. SIDS is the most common cause of death in infants 2 weeks to 1 year of age. Distribution is worldwide, and the incidence in the United States is 1.5 in 1,000 live births. More than 7,000 infants die each year in the United States alone. Males are affected more often than females, as are Native Americans and blacks. The incidence is higher in the winter, with January the peak month of occurrence.

Disease Process

The pathophysiology is unknown, but pathology results on autopsy are consistent and include findings of pulmonary edema and intrathoracic hemorrhages.


The infant is usually found dead in the bed or crib. The bedclothing tends to be disheveled, and the infant is often huddled in a corner face down with the covers over the head. The infant’s hands are often clutching the sheets. Frothy, blood-tinged fluid is in the mouth and nose, and stool and urine fill the diaper.

Potential Complications

The syndrome is fatal.

Diagnostic Tests

The diagnosis is confirmed by postmortem examination, including examination of the site of death.


Management focuses on helping the family to cope and on preventing the disorder in infants seen as high risk.


Respiratory stimulant medications for high-risk infants to prevent SIDS.

Intensive psychologic and emotional support of the family from the time of health care contact for at least 1 year, including time to say goodbye to the infant at the emergency center, arranging transportation home, an immediate home visit to allow family to talk and to discuss SIDS (written supplemental material is desirable), support group and counseling referrals, follow-up home visits Preventive measures: identification of infants with high-risk profiles (one or more previous apparently life-threatening events, preterm, SIDS history of two siblings in family, episode of apnea, excessive periodic breathing, central hypoventilation); use of home monitoring devices; nonprone sleeping position for all infants.