A comparison of apparent life-threatening events before and after the back to sleep campaign.

OBJECTIVES: The incidence of the Sudden Infant Death Syndrome (SIDS) has decreased significantly in the United States since the 1992 recommendation that healthy term infants be placed on their backs or sides during sleep. However, little is known regarding the effect that this recommendation has had on the incidence and epidemiology of apparent life-threatening events (ALTEs) in this country. METHODS: To examine this, we completed a retrospective chart review study of all infants admitted to the Children's Hospital of Wisconsin with the diagnosis of an ALTE during two study periods before and after the back to sleep initiative: January 1, 1991 to December 31, 1992 and January 1, 1996 to December 31, 1997. RESULTS: There were 81 ALTEs in 1991-1992 vs. 102 in 1996-1997. Infants in both groups were similar with respect to gender, race, and age, with approximately 80% in each group < 4 months of age. ALTEs occurred equally throughout the year during both time periods. The majority of episodes occurred during sleep; 74% of the 1991-1992 cohort and 59% of the 1996-1997 infants did not have information in the medical record describing their position during the ALTE. Three infants (2 during 1991-1992) died during the hospitalization and were subsequently diagnosed with SIDS or probable SIDS.

Apnea and bradycardia due to anaphylaxis to tobacco glycoprotein in the infant rabbit.

Prenatal and postnatal exposure to cigarette smoke is associated with an increased incidence of the sudden infant death syndrome, although the cause(s) for this is unknown. Tobacco glycoprotein (TGP), a group of proteins purified from cured tobacco leaves and present in cigarette smoke, have been shown to cause anaphylaxis in excised hearts and lungs of adult rabbits that were neonatally sensitized to TGP and later rechallenged. We sought to determine whether anaphylaxis occurred in live infant rabbits who were neonatally sensitized to TGP. At the age of 1 day, 12 animals were sensitized to TGP (0.1mg in 0.25 cc alum) via intraperitoneal injection (i.p.i.) followed by a booster ipi at the age of 30 days (TGP-S). Seven animals received i.p.i. of antigen-free alum only (controls). All animals underwent an intravenous TGP challenge at age 42+/-2 days. Heart rate (HR) and respiratory rate (RR) were recorded for 2 min prior to and 5 min after the challenge. Baseline HR (approximately 260) and RR (approximately 120) were similar in all animals. Seven TGP-S animals developed apnea (1.9-4.7s) within 60s of the challenge while none of the controls did. The TGP-S also became bradycardic (the lowest HR over 50 consecutive beats), with the HR decreasing from 260 to 220 vs the controls, whose HR remained constant (approximately 250). We conclude that some rabbits neonatally sensitized to TGP develop apnea and bradycardia upon further intravenous TGP challenge. These studies suggest that cigarette smoke exposure may be associated with a higher rate of SIDS via an anaphylactic mechanism.