Comparison of Apnea Identified by Respiratory Inductance Plethysmography with That Detected by End-tidal CO2 or Thermistor

As part of the Collaborative Home Infant Monitoring Evaluation (CHIME) we compared apnea identified by a customized home monitor using respiratory inductance plethysmography (RIP) with simultaneously recorded polysomnography-acquired nasal end-tidal CO2 (Pet CO2 ) and nasal/oral thermistor in 422 infants during overnight laboratory recordings to determine concordance between techniques, sources of disagreement, and capacity of RIP to detect obstructed breaths within an apnea. Among 233 episodes of apnea identified by at least one method as ⩾ 16 s, 120 were observed by the CHIME monitor, 219 by Pet CO2 , and 163 by thermistor. The positive predictive value of the CHIME-identified apnea was 89.2% (95% CI 83, 95) and 73% (95% CI 65, 81) for Pet CO2 and thermistor, respectively. However, the sensitivity of the CHIME monitor in identifying events detected by the other methods was only ∼ 50%. Among 87 apnea events identified by all three techniques, no two methods showed high agreement in measurement of apnea d...