Sudden infant death syndrome and apnea of infancy

An abnormality in brainstem maturation of cardiorespiratory control continues to be the most compelling hypothesis for sudden infant death syndrome (SIDS). An arousal or gasping deficit appears to be a necessary but not necessarily sufficient factor. Due to these uncertainties as to the cause or causes of SIDS, prospective identification studies have not been helpful in at-large infant groups and have not been systematically performed in any of the asymptomatic groups at increased epidemiologic risk. Since prospective identification is of limited benefit in the absence of an effective intervention, a major priority now is to conduct home intervention studies in asymptomatic at-risk infants to determine if a comprehensive home intervention program can significantly reduce infant mortality. Documented monitoring (in-home cardiorespiratory monitoring with computer memory analysis, see discussion later in this article) is a powerful diagnostic tool that should provide substantial and important clinical information regarding the cardiorespiratory abnormalities causing clinical events and monitor alarms. Documented monitoring during the actual occurrence of SIDS will, for the first time, yield firsthand evidence of the cardiorespiratory pattern abnormalities causing or associated with the terminal event. Documented monitoring will identify and permit further avoidance of excessive or unimportant alarms and should thus maximize parental compliance. Prospective studies to determine the efficacy of comprehensive home interventions, including electronic surveillance, are thus a major clinical research priority. Documented monitoring will be invaluable in successful surveillance programs and is thus a major clinical research priority as well. Documented monitoring should prove invaluable in the successful conduct of such studies, in interpreting the cardiorespirtory events so obtained, and in analyzing the cardiorespiratory changes associated with sudden death. The following sections summarize the current status of our knowledge in regard to pathophysiology of SIDS, risk groups, intervention strategies, clinical management of apparent life-threatening events (ALTEs) and apnea of infancy, and documented monitoring.