Abstract: This disclosure provides a method for evaluating volume responsiveness and a medical device. The medical device includes a respiratory assistance device for providing respiratory support for a patient, and a first sensor for collecting physiological parameters of the patient and a processor. When volume responsiveness evaluation is needed, the processor controls ventilation parameters to switch to a second ventilation parameter that may increase the variation of the intrathoracic pressure of the patient, and then uses a parameter variation capable of reflecting the heartbeat of the patient to evaluate whether the patient is volume responsive.

Abstract: The disclosure provides a respirator, which includes a ventilation device, configured for providing ventilation airflow to a patient. The respirator further includes a first monitor, configured for monitoring a pressure or a flow velocity with which the ventilation device ventilates the patient, and a second monitor, configured for measuring a pressure change that reflects a self-respiratory effort of the patient. The respirator also includes a processor, configured for identifying an inspiratory trigger moment or an expiratory trigger moment of the patient according to the pressure change that reflects the self-respiratory effort of the patient.