The collaborative home infant monitoring evaluation (CHIME) developed a research monitor (NIMS, Inc., Miami, FL) that detects breaths with RIP, and simultaneously records TTI. To assess the accuracy of measurement of apnea duration for RIP and TTI, we compared the duration of 108 apneas (median duration 12 s., extremes 10 - 31 s.) from 17 overnight PSG recordings with the duration based on independent measurement from synchronized, simultaneously recorded RIP and TTI. Subjects included 1 SIDS sibling, 4 infants with apnea of infancy, 7 preterm infants, and 5 healthy term infants; 1-22 wks of age. Based on the PSG, there were 59 central apneas (absent airflow, absent effort), 39 apneas with 1-3 obstructed breaths (continued respiratory efforts, no airflow by nasal end tidal carbon dioxide or nasal/oral thermistor) and 16 apneas with >3 obstructed breaths. The figure shows the differences in duration between RIP and TTI vs. PSG. Differences in duration increased with the number of obstructed breaths. RIP was reasonably close to PSG and was consistently closer than TTI regardless of event category. (NICHD HD 29067 29071 28971 29073 29060 29056 34625)

figure 1