The infant car restraint devices are a critical part of infant safety during transportation. The crash tolerance and the critical safety features of each seat are well established. Infant transportation may be via a car seat or car bed. The effect of the sitting position on the airway is a concern in an infant with poor head control. Because of this concern, car seat tests during which oxygen saturation is measured, are performed on many low birth weight infants before discharge from the nursery. Indeed, a number of deaths have occurred in car seats probably related to airway obstruction. The relative effects of position on the ventilation need to be established.

We propose to identify the relative changes in ventilation that are induced by position change during sleep. We will collect a broad array of high quality data that will identify these changes, and the most likely cause. Specifically, we will we screen 200 infants, with each infant assigned to the supine position, the car bed and the car seat. The order of these positions will be randomly assigned. Following data will be collected:

1. Relative changes in ventilation will be assessed by oxygen saturation measurement.
2. Respiratory movement will be measured in order to define the defect.
3. Once the data is collected, it will be sent for blind data analysis.
4. Once the data analysis is complete, the effect of position on ventilation will be established.