Abstract: A system (100) and method for delivering oxygen to, and preventing hypercapnic respiratory failure in, a patient (1) include an oxygen dosing unit (10) and a sensor arrangement (40), the oxygen dosing unit adapted to provide an oxygen flow (12) to a port (13) fluidly connectable to an oxygen delivery unit (30) attached to the patient, the oxygen dosing unit further adapted to regulate parameters of the oxygen flow based upon a first input signal indicating an oxygen status of the patient and a second input signal indicating a carbon dioxide status of the patient, wherein the sensor arrangement includes sensing means (42, 43) adapted to obtain a first sensor value corresponding to the oxygen status via a non-invasive transcutaneous measurement and a second sensor value corresponding to the carbon dioxide status via a non-invasive transcutaneous measurement, the sensor arrangement adapted to provide the first and second input signals on the basis of the first and second sensor values, and the oxygen dosing unit