A method for performing a medical procedure requiring effective, reliable and foolproof delivery of controlled amounts of a medical grade gas to a patient includes providing a compressed gas cylinder having a weight with medical grade gas sealed therein of at least twelve grams and not greater than fifty grams. The method also includes connecting the compressed gas cylinder to an integrated compressed gas unit including a regulator valve assembly positioned between an outlet port and an inlet port, wherein the regulator valve assembly includes a press button actuator and regulator adjustment dial. A flow control system is secured to the compressed gas unit and the medical grade gas is delivered in precisely controlled amounts by actuating the compressed gas unit and operating the flow control system to deliver the medical grade gas to vasculature of the patient.
