Sudden Infant Death Syndrome

By Edward James, MD

Sudden Infant Death Syndrome (SIDS) is a devastating problem affecting one to two infants per 2,000 born. It is the number one cause of death among infants during the first year of life.

SIDS is the sudden and unexpected death of an infant, usually between two weeks and six months of age, with no identifiable cause. The conclusion that there is no identifiable cause can be reached only after obtaining a thorough history, performing an autopsy and investigating the scene where the infant was found. The vast majority of the victims were born full-term and were healthy prior to the event.

There are numerous theories to explain the phenomenon; however, none has been successfully proven. It is most likely that SIDS is more than one disease. There are likely many paths leading to death in these healthy-looking infants.

Some factors are known to affect the risk of SIDS. Breastfeeding, for example, has been associated with a decrease in the risk. On the other hand, cigarette smoking in the house increases the risk of SIDS six times. In addition, over-clothing, especially during the winter months, is also associated with somewhat increased risk. Infants who are kept too warm have difficulties controlling their breathing. Infants have a good ability to control their body temperature; thus, the number of layers of clothing when dressing an infant should not be different than the number of layers adults in the household are wearing.

The bed in which the infant is sleeping should be free of fluffy pillows, comforters and stuffed animals. These can cover the infant’s face and obstruct the airway.

Since the cause for SIDS is not known there are no tests that can be used to identify infants at risk. Fortunately, though, there is information available which has led to the development of guidelines that should be applied when caring for infants.

Studies have shown that the risk of SIDS is higher when infants sleep on their stomach (prone). This is most likely because infants have weak neck muscles, which reduces their ability to lift and turn their heads if they end up in a face down position. As a result, when placed prone the risk of smothering is higher than when placed on the back (supine). It is the recommendation of the American Academy of Pediatrics that infants be put to sleep in the supine position (“Back To Sleep”). This is especially important when the infant is unsupervised. When the caregiver is in the room with the infant, the infant can be put in any position. It is only when the caregiver leaves the room that the supine position should be used.

The worry about increased spitting and choking when lying on the back was not substantiated in numerous studies. In some cases, though, when the infant has a significant degree of spitting (gastro-esophageal reflux), a discussion should take place with the physician to evaluate which sleep position is better for that specific infant.

SIDS is an extremely tragic event that may be prevented when using the above mentioned precautions. Parents should educate themselves and the other people who take care of their infants during the first months of life.

Additional information can be obtained from Family Practitioners, Pediatricians, the American Academy of Pediatrics at www.aap.org or the SIDS Alliance (800/221-SIDS).

Dr James is the director of the Newborn Services at the Danbury Hospital and can be reached at 203/797-7150.