Breath-Alert Breath Detection System

Vanderbilt University, 2001 - $10,440

Approximately 2,500 infants suffered Sudden Infant Death Syndrome (SIDS) in 1998. Although decreasing, the numbers of SIDS cases is still quite large. Caregivers typically discover the occurrence of SIDS when they check on a sleeping infant. Closely monitoring an infant's breathing gives warning when a problem arises. Breath monitoring is also necessary in other medical cases, such as post-operative patients who have received anesthesia and sleep apnea patients.

The Breath-Alert device, developed by an E-Team of two MBA students and two graduate students in biomedical engineering, is a general purpose breath monitoring system appropriate for post-operative patients, sleep apnea patients, and infants at risk of SIDS. The device measures carbon dioxide levels to determine whether or not the patient is breathing. Carbon dioxide absorbs light in the 4.2 to 4.4 bandwidth, so the device uses infrared (IR) light to detect carbon dioxide in the ambient air around the patient. Breath-Alert positions an IR source tuned to the appropriate wavelength and power to shine its beam through the exhaled volume of gas. A parabolic reflector placed opposite the source concentrates the IR light at its focal point, and an IR sensor at the focal point detects the transmitted light. A simple algorithm processes the IR transmission data and signals an alarm when breathing ceases.