Inspiratory pressure control in volume mode ventilation

A method to deliver a pressurized flow of breathable gas to the airway of a subject with a mechanical ventilator system, the mechanical ventilator system comprising a pressure generator, one or more sensors, a user interface, and one or more processors, the one or more processors configured to execute computer program modules, the computer program modules comprising a control module, a gas parameter module, an airway parameter module, and an inspiratory pressure module, the method comprising:

• generating the pressurized flow of breathable gas with the pressure generator;
• generating output signals conveying information related to one or more gas parameters of the pressurized flow of breathable gas with the one or more sensors;
• receiving entry and/or selection of control inputs that select a target tidal volume with the user interface;
• controlling operation of the pressure generator to generate the pressurized flow of breathable gas according to a volume control mode therapy regime that delivers the target tidal volume with the control module;
• determining one or more gas parameters of the pressurized flow of breathable gas based on the output signals with the gas parameter module, wherein the one or more gas parameters are determined multiple times per inhalation of the subject;
• determining one or more airway parameters of the airway of the subject with the airway parameter module, wherein the one or more airway parameters are determined multiple times per inhalation of the subject;
• and
• dynamically determining an inspiratory pressure level of the pressurized flow of breathable gas of the volume control mode therapy regime during an inhalation to achieve the target tidal volume, with the inspiratory pressure module, the determination based on the determined one or more airway parameters and the determined one or more gas parameters;
• determining, with the inspiratory pressure module, whether the target tidal volume is exceeded during the inhalation;
• and
• maintaining with the inspiratory pressure module, responsive to the target tidal volume being exceeded during the inhalation, the inspiratory pressure level during the inhalation so the inspiratory pressure level is not reduced to impede respiratory effort by the subject, wherein maintaining comprises adjusting the inspiratory pressure level with the inspiratory pressure module based on inner loop parameters and outer loop parameters, wherein the inner loop parameters comprise one or more of gas parameters determined multiple times during the inhalation by the subject, or airway parameters determined multiple times during the inhalation by the subject, and wherein the outer loop parameters comprise one or more of gas parameters determined based on an immediately previous inhalation by the subject, or airway parameters determined based on the immediately previous inhalation by the subject.

A mechanical ventilator system configured to deliver a pressurized flow of breathable gas to the airway of a subject, the mechanical ventilator system comprising:

• means for generating the pressurized flow of breathable gas;
• means for generating output signals conveying information related to one or more gas parameters of the pressurized flow of breathable gas;
• means for receiving entry and/or selection of control inputs that select a target tidal volume;
• and
• means for executing computer program modules, the computer program modules comprising:
• means for controlling operation of the means for generating the pressurized flow of breathable gas to generate the pressurized flow of breathable gas according to a volume control mode therapy regime that delivers the target tidal volume;
• means for determining one or more gas parameters of the pressurized flow of breathable gas based on the output signals, wherein the one or more gas parameters are determined multiple times per inhalation of the subject;
• means for determining one or more airway parameters of the airway of the subject, wherein the one or more airway parameters are determined multiple times per inhalation of the subject;
• means for dynamically determining an inspiratory pressure level of the pressurized flow of breathable gas of the volume control mode therapy regime during an inhalation to achieve the target tidal volume, the determination based on the determined one or more airway parameters and the determined one or more gas parameters;
• means for determining whether the target tidal volume is exceeded during the inhalation;
• and
• means for maintaining, responsive to the target tidal volume being exceeded during the inhalation, the inspiratory pressure level during the inhalation so the inspiratory pressure level is not reduced to impede respiratory effort by the subject by adjusting the inspiratory pressure level based on inner loop parameters and outer loop parameters, wherein the inner loop parameters comprise one or more of gas parameters determined multiple times during the inhalation by the subject, or airway parameters determined multiple times during the inhalation by the subject, and wherein the outer loop parameters comprise one or more of gas parameters determined based on an immediately previous inhalation by the subject, or airway parameters determined based on the immediately previous inhalation by the subject.