Pathophys:Etiology unknown. URI and nasal obstruction precipitate some events. Some may be assoc w long QTc >0.44 on EKG (Jama 2001;286:2264; Nejm 1998;338:1709), may be mutation in cardiac voltage-gated Na channels (J Clin Invest 2006;116:297), or medullary 5-HT deficiency (Jama 2010;303:430). Correlates w maternal 2nd trimester -fetoprotein levels (Nejm 2004;351:978)

1.4 deaths/1000 live births in US. Runs in families; no association w DPT immunizations (J Peds 1991;119:411); increased incidence by sleeping prone and by deformable mattress, swaddling, warm room, URIs (Nejm 1993;329:377, 425), and children exposed to passive cigarette smoke (Jama 1995;273:795); link w Munchausen’s (Lancet 2004;328:1309)

Incidence decreased by 40% to <1/1000 w public education against sleeping prone (Pediatr Ann 1995;24:350) but message hardest to get to lower socioeconomic groups (Jama 1998;280:329, 336, 341)

r/o trauma/smothering asphyxia (Nejm 1991;324:1858; 1986;315:100, 126), Munchausen by proxy

Lab: May be associated with elevated Hgb F levels (Nejm 1987;316:1122 vs 1989;321:1359), and some subset of cases w long QT interval (Nejm 2000;343:262; 1987;317:1501)

Rx:

Prevent by positioning children supine (on back; “back to sleep” campaigns) (Jama 2001;285:2244; 1995;273:818; 1994;272:1646) for 1st 6 mo of life (BMJ 1991;303:1209), doing so reduced incidence in Tasmania from 3.8 to 1.5 deaths/1000 (Jama 1995;273:783) and by 90% in Norway (J Ped 1998;132:340) but no difference found in southern California (Jama 1995;273:790); avoid soft bedding under infant. Apnea monitors not effective (Jama 2001;285:2199, 2244)

Temperature control in newborn is poor; higher ambient temperature may precipitate apnea (Nejm 1970;282:461); hypothermia immediately postpartum decreases with plastic swaddle in both newborn premie and term babies (Nejm 1971;284:121).