Abstract: The present invention discloses a method for improving control and detection precision of tidal volume by introducing R value, comprising the steps of: a plateau pressure Pplate is used to calculate a system compliance C with C=?V/(Pplate?PEEP); VT, the tidal volume obtained currently at patient terminal, is calculated with VT=?V×(C?Ctube)/C, wherein ?V is the variation of tidal volume, PEEP is the positive end expiratory pressure and Ctube is the compliance C of the line. Depending on the calculated VT, the tidal volume which is actually obtained by the patients during this period, the processing unit calculates the tidal volume VT?, which the airway is intended to reach during the next expiration period, by VT?=VT+?VT×K wherein K is a scaling factor for control and adjustment, VT is the tidal volume obtained by the patient during the current period, VTset is the presetted tidal volume, ?VT=VTset?VT.

Abstract: The present invention discloses a method for improving control and detection precision of tidal volume by introducing R value, comprising the steps of: a plateau pressure Pplate is used to calculate a system compliance C with C=?V/(Pplate?PEEP); VT, the tidal volume obtained currently at patient terminal, is calculated with VT=?V×(C?Ctube)/C, wherein ?V is the variation of tidal volume, PEEP is the positive end expiratory pressure and Ctube is the compliance C of the line. Depending on the calculated VT, the tidal volume which is actually obtained by the patients during this period, the processing unit calculates the tidal volume VT?, which the airway is intended to reach during the next expiration period, by VT?=VT+?VT×K wherein K is a scaling factor for control and adjustment, VT is the tidal volume obtained by the patient during the current period, VTset is the presetted tidal volume, ?VT=VTset?VT.

Abstract: The present invention discloses an airway system and operating method thereof in the medical equipments such as a ventilator and an anesthetic machine. The airway system comprises: a respiratory circuit (2) comprising an inspiratory branch (21) and an expiratory branch (22); a control unit (1) connected to the respiratory circuit (2) for controlling the opening and closing of the inspiratory and expiratory branches; an airway pressure sensor (7) located in the respiratory circuit (2) for measuring the airway pressure, wherein an ambient pressure sensor (5) is also located in the respiratory circuit (2), and wherein in the normal operating mode, the ambient pressure sensor (5) is used to measure the ambient pressure, while when failures occur in the airway pressure sensor (7) it is used to roughly measure the airway pressure.