A device and method for deploying a mechanical closure device for closing a passageway in a body, for example a patent foramen ovale in a heart. An inverter circuit converts a DC voltage from a DC power source into a voltage having a determined frequency, and supplies the converted voltage to the discharge lamp inserted between a pair of output ends of the inverter. The measured pressure drop is then used by the gauge to determined the rate of air flowing through the line. Z1 represents one of formula to, and Z2 represents hydrogen or one of formula to or a group the same as Z1.