An apparatus for providing backup ventilation to a patient comprising: a respirator adapted to generate and administer ventilatory support to a patient； and a controller (4) configured to control the ventilatory support provided by the respirator, the controller (4) being configured with a spontaneous mode in which the synchronized cyclic ventilatory support is initiated detecting the presence of a patient's respiratory cycle； the controller (4) being also configured with a timed mode in which a cyclic ventilatory support is administered according to a timing threshold in the absence of a detection of the patient's respiratory cycle, and characterized in that the controller (4) is configured to establish the timing threshold as a function of the normal respiratory timing expected for the patient, said function being chosen to deviate the timing threshold from the normal respiratory timing expected for the patient so that the timing threshold is associated with a respiratory rate that is lower than the patient's respiratory rate to promote patient-initiated synchronization of the ventilatory support but allowing backup ventilation in case of apnea.Un aparato para proporcionar ventilación de respaldo a un paciente que comprende: un respirador adaptado para generar y administrar soporte ventilatorio a un paciente； y un controlador (4) configurado para controlar el soporte ventilatorio proporcionado por el respirador, estando configurado el controlador (4) con un modo espontáneo en el que se inicia el soporte ventilatorio cíclico sincronizado detectando la presencia de un ciclo respiratorio del paciente； estando configurado además el controlador (4) con un modo temporizado en el que se administra un soporte ventilatorio cíclico según un umbral de temporización en ausencia de una detección del ciclo respiratorio del paciente, y caracterizado porque el controlador (4) está configurado para establecer el umbral de temporización en función de la temporización respiratoria n
