A respiratory assistance apparatus (1) for delivering a flow of gas to a patient (P) comprises a gas delivery conduit (2) for conveying a flow of gas, measuring means (6) designed to measure at least one parameter representative of the flow of gas and to supply at least one signal corresponding to said parameter, signal-processing means (8) designed to process said signal coming from the measuring means and to deduce from said signal at least one item of information relating to performaace and/or discontinued performance of chest contractions (CT), calculating means designed to calculate at least one duration of discontinuation or absence of chest contractions (tNCT), and storage means (12) configured to register said duration of discontinuation or absence of chest contractions.
