Abstract: Apparatus and process for injection of a gas, preferably carbon dioxide, comprising a source of the gas connected to at least two conduits (C) each provided with a control valve (EV) and a control (Q) of the gaseous flow rate. All of the conduits (C) open into a single channel (B), provided with a three-way control valve (V). The control (Q) of the gaseous flow rate is a calibrated orifice. The control valve (EV) and three-way control valve (V) are electrovalves. The channel (B) is connected to a catheter for injection of the gas into a body. The controls (Q) each permit a different flow rate through the associated control valve (EV), whereby a range of total flow rates of gas into the channel can be achieved by opening and closing selected ones of the controls.

Abstract: A duct opening close to the patient's respiratory passages provides a supply of additional oxygen from a source.The device comprises a heat sensor element exposed to the temperature changes between the air inhaled and the air exhaled which cause corresponding voltage changes across its terminals; a coupler supplying signals which are a function of these voltage changes; an electromagnetic valve in the duct and controlled by a control element during the patient's various stages of respiration.The invention is applicable more particularly to oxygen therapy devices worn on the person e.g. in the fashion of spectacles.