Non-invasive Tidal Volume Monitoring Using the Linshom Respiratory Monitoring Device

Volunteers will breathe through a continuous positive airway pressure (CPAP) face mask fitted wth the Linshom device. The volunteers will be instructed to breathe normal through the CPAP mask on room air. The excursions of the thermistor tracings (from valley to peak) will be recorded by the Linshom device and displayed continuously on a laptop monitor in a waveform. The tidal volume will also be measured by the ventilator and the data downloaded in a Compact Flash card.