Patent RU-2712843-C2 (RU)
Title: Systems and methods for detecting disconnection of artificial pulmonary ventilation apparatus from patient using assessment of lung compliance of patient's lungs on respiratory phases of inhalation and exhalation
Inventor: ISAZA Fernando Khose
IPC: A61M16/00
Filed: 2015-12-17
Granted: 2020-01-31
Abstract: FIELD: medicine. 
     SUBSTANCE: group of inventions relates to medical equipment, specifically to a ventilating circuit of an artificial ventilation apparatus for delivering a respiratory mixture to a patient having a respiratory cycle, comprising an inhalation phase and an exhalation phase, method of determining patient disconnection from respiratory circuit of ALV machine and non-volatile computer-readable data medium. Respiratory circuit comprises a gas supply device. Respiratory circuit has a system of patient tubes connected to said gas feed device. Respiratory circuit includes a gas monitoring system connected to said patient tube system and configured to monitor flow rate and pressure. Respiratory circuit comprises a control unit connected to the above monitoring system and configured to determine the patient's disconnection from the respiratory circuit of the ventilator by assessing the degree of compliance of the patient's lungs on the basis of certain volumes of gas delivered during the inhalation phase of the respiratory cycle and released during the breathing cycle respiration, and measured pressures in said patient tube system during respiratory cycle inhalation and exhalation phases. Control unit is designed to assess a degree of compliance of the patient's lungs by evaluating compliance of the patient's lungs during inhalation during the inhalation phase of the respiratory cycle, and assessing flexibility of the patient's lungs during exhalation during the breathing cycle exhalation phase; wherein degree of compliance of patient's lungs is equal to value (C inh / C exh ); where C inh  - compliance of patient's lungs during inhalation, evaluated during inhalation phase and calculated as C inh = V inh / (P eoi  - P boi ); C exh  - pliancy of patient's lungs during exhalation, evaluated during the phase of exhalation and calculated as C exh = V exh / (P eoi  - P eoe ); where V inh  = volume of gas delivered during inhalation phase, V exh  = volume of gas released during the phase of exhalation, P boi  = pressure measured in the patient's tube system at the beginning of the inhalation phase, P eoi  = pressure measured in patient tube system at end of inhalation phase, P eoe  = pressure measured in the patient's tube system at the end of the exhalation phase. Control unit is configured to determine the patient's disconnection from the respiratory circuit of the ventilator by comparing the assessed degree of compliance of the patient's lungs with the threshold value. Method includes monitoring of gas flow rate and pressure in said system of patient's tubes. Method involves assessing the degree of compliance of the patient's lungs on the basis of certain volumes of gas delivered during the inhalation phase of the respiratory cycle and released during the expiration phase of the respiratory cycle, and measured pressures in the patient's tubes system during the inhalation and exhalation phases of the respiratory cycle. Method involves determining a patient's disconnection by comparing the assessed degree of compliance of the patient's lungs with a threshold value. Non-volatile computer-readable data medium contains computer-readable instructions stored thereon and configured to be executed by a processor for controlling the respiratory circuit of the ventilator to deliver the respiratory mixture to the patient. 
     EFFECT: technical result is a reliable hardware-independent approach for determining patient disconnection in the respiratory circuit of the pulmonary ventilation system. 
     18 cl, 2 dwg