Date of Award



Biomedical and General Engineering


Lily Laiho


The focus of this thesis was to capture and measure carbon dioxide concentrations upon exhalation to determine if an apnea event is occurring. Research in the fields of respiratory physiology and apnea built the foundation for the design of the standoff infant apnea monitor. The monitor is designed to track infant respiration using carbon dioxide and sound signatures of breath without touching the infant. Each detection system, audio and carbon dioxide, were designed separately and brought together for a final proof-of-concept device. The software was developed using LabView and run on a Netbook. Testing was conducted on healthy adults to fine tune the carbon dioxide sensor and measure its response during simulated apnea events. Overnight testing showed that the combined system detected fewer false alarms than either system alone. Infant testing was conducted to determine if the proof-of-concept standoff monitor could detect infant breath at specified distance. The results showed that both detection systems can detect infant breath consistently at distances less than one foot from the infant and poorly at distances exceeding one foot. Finally, conclusions were drawn and interpreted to aid in the design of future generations of the standoff infant apnea monitor. Other research avenues where this technology may be useful were also discussed.