Sudden infant death syndrome is defined as a death in an infant or young child that is unexpected and unexplained by history, thorough autopsy, and investigation of the death scene. At the present time there are no known screening tests to predict SIDS.

Epidemiology

1. SIDS is the leading cause of death in infants between 1-6 months. Rare <1 month
2. 95% of infants are < 6months old. 85% are between 2-4 months of age
3. In the United States the incidence is 1.3/1000 live births with a higher incidence in males
4. The incidence is higher in Native Americans>African Americans> Caucasians> Asians
5. Incidence is highest in winter.
6. Increased incidence with mothers who smoke during pregnancy and passive smoke exposure postnatally. 
7. Relationship to Acute Life Threatening Events (ALTE) unclear
8. Higher incidence if sib died from SIDS. This suggests a genetic or metabolic role and possible child abuse. 
9. 2000 grams at birth have higher incidence
10. Prenatal exposure to "street" drugs increases risk of SIDS
11. Recent epidemiological studies have demonstrated a fall in incidence with supine sleep position compared to prone and sleeping on the side.
12. A recent NEJM article discussed the relationship between the prolonged QT interval and SIDS.

1. At postmortem, consistent findings include pulmonary edema, intrathoracic petechiae, and findings consistent with chromic hypoxia. 
2. Areas of study include brainstem dysfunction, temperature regulation, cardiorespiratory control, sleep abnormalities, and arousal patterns.
3. Recent study (NEJM) demonstrated prolonged QTc on ECG at 4 days of age associated with increased incidence of SIDS

1. "Back to Life". Campaign started by AAP to promote sleeping in supine position
2. Decrease smoke exposure during and after pregnancy
3. Firm mattress
4. No pillow or stuffed animals in the crib
5. No relationship between SIDS and immunizations must be emphasized to parents.

1. There are few things more devastating to a family than the sudden unexpected death of an infant. It is important for the pediatrician to be in contact with the family soon after the event to obtain a thorough history and permission for an autopsy. It is imperative that the death scene is investigated. Parents must be reassured that they did not contribute to the death of the infant and it was not preventable. Avoid accusations.
2. As soon as the autopsy results are known, the parents must be informed of the findings
3. 4-6 weeks after the death, the parents should visit the pediatrician to discuss any questions that the family may have.
4. The parents and family can be directed to organizations that are available for parents of SIDS victims. Not all parents are interested in joining groups, so do not force this upon them.
5. If the mother becomes pregnant again, make yourself available for questions. In addition, after the birth of the next child, be prepared for the mother to be very anxious until the high incidence periods of SIDS has passed or until the new infant live past the time the previous child died. The family may request a monitor, sleep/apnea studies, refuse immunizations, and call often. Be patient.

1. American Academy of Pediatrics Changing Concepts of Sudden Infant Death Syndrome: Implications for Infant Sleeping Environment and Sleep Position Pediatircs Vol 105 No. 3  pg. 650- 654 March 2000.
2. Barness, Eric Gilbert and Barness, Lewis. Sudden infant death: A reappraisal. Contemporty Pediatrics. April 1995.
3. Leach CEA et al. Epidemiology of SIDS and Explained Sudden Infant Death. Pediatrics. 1999; 104(4):e43.
4. American Academy of Pediatrics. Apnea, Sudden Infant Death Syndrome, and Home Monitoring.. Pediatrics Vol.111 April 2003
5. Task Force on Sudden Infant Death Syndrome The Changing concept of Sudden Infant Death Syndrome.  Pediatrics Nov 2005
6. Hauck FR. Do Pacifers Reduce the Risk of SIDS? Pediatrics Nov 2005 e716