The invention discloses a ventilation method for ensuring volume and limiting pressure of an
anesthesia machine and a
breathing machine. The method comprises the following steps of: self-detecting the pipeline compliance of the
anesthesia machine and the
breathing machine in the startup process; in the process of starting
breathing control, when the air resistance (R) value and the compliance (C) value of a patient are not monitored correctly, using a volume
ventilation mode and monitoring the R value and the
C value of the patient in the ventilation period; if the R value and the
C value of the patient are correctly monitored, monitoring the suction volume of the patient in a suction period by a compliance compensated volume ensuring method, and performing volume ensuring
processing after a set volume is achieved; and calculating a standard control pressure value P of a
system, performing suction valve and expiration valve cooperative
pressure control according to the value P, calculating the expiration
tidal volume of the patient, a volume difference value and a
pressure difference value
Delta P at an expiration stage, and performing feedback compensation control on the calculated value P according to the
Delta P so as to ensure the volume and the pressure.