This invention relates to an artificial breathing apparatus comprising a patient circuit (1) carrying gas comprising an inspiratory branch (2), and at least one pressure sensor arranged so as to operate at least one pressure measurement within the patient circuit (1), characterised in that it comprises a differential pressure sensor (4) and an absolute pressure sensor (5) located on the inspiratory branch (2), and control means cooperating with the differential pressure sensor (4) and the absolute pressure sensor (5) to detect a failure or malfunction of one or other of the said differential pressure (4) and absolute pressure sensor (5). The apparatus covered by the invention can be used in the treatment of chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS) or in post-operative care.