Abstract: This invention discloses a modular system having a base module, a mid-section control module, and a display module for preparing and administering a gas-enriched bodily fluid. Gas-enrichment is achieved by a gas-enriching device which can be in the form of a disposable cartridge. During operation, the gas-enrichment device is placed in an enclosure within the control module. An electronic controller manages the various aspects of the system such as the production of gas-enriched fluid, flow rates, bubble detection, and automatic operation and shut down. The system includes a combination bubble detector/flow meter that uses a single ultrasonic probe for measuring both bubbles and fluid flow rate.