 This clinical study has been designed to compare the ProSeal, ETC and LTS-D as to the ease of placement and ventilation during controlled ventilation, proper positioning, the seal pressure with each placement, the patency of the drain tube by suctioning and measuring stomach contents, and finally, any complications with their use. Fiberoptic observations through each device will provide information in relation to the epiglottis and the distal opening of the device. 