Automated inspiratory muscle training for patients receiving mechanical ventilation

Abstract

A system and method for automated inspiratory muscle strength exercise includes software for setting a mechanical ventilator for a pressure regulated breath with an initial pressure target that is at the highest pressure setting a patient can tolerate and increasing the pressure target as tolerated.

1 . An inspiratory muscle strength training system comprising:
 a gas delivery assembly configured to provide inspiratory air flow to a patient during spontaneous patient inhalations;   a patient interface comprising an airway, the patient interface configured for delivering inspiratory air flow from the gas delivery assembly to the patient via the airway;   a sensing assembly comprising one or more sensors configured to sense one or more patient respiratory parameters, the one or more patient respiratory parameters including an airway pressure within the airway of the patient interface; and   a microcontroller assembly in communication with the gas delivery assembly and the sensing assembly, wherein the microcontroller assembly is configured to execute an inspiratory muscle strength training mode in which the microcontroller assembly causes inspiratory air flow to be delivered from the gas delivery assembly to the patient in response to the airway pressure falling below an inspiratory training pressure threshold and, in response to the airway pressure exceeding the inspiratory training pressure threshold, temporarily decreasing supply of inspiratory air flow from the gas delivery assembly to the patient.   
     
     
         2 . The system according to  claim 1 , wherein the microcontroller is configured such that temporarily decreasing supply of inspiratory air flow from the gas delivery assembly to the patient comprises ceasing the supply of inspiratory air flow from the gas delivery assembly to the patient. 
     
     
         3 . The system according to  claim 1 , wherein the microcontroller assembly is further configured to execute the inspiratory muscle strength training mode in training sets each having a duration comprising a defined number of spontaneous patient inhalations. 
     
     
         4 . The system according to  claim 3 , wherein the defined number of spontaneous inhalations is between six and ten spontaneous inhalations. 
     
     
         5 . The system of  claim 3 , wherein the microcontroller assembly is further configured to execute between two and five training sets over a twenty-four hour period. 
     
     
         6 . The system according to  claim 1 , wherein the microcontroller assembly is further configured to execute the inspiratory muscle strength training mode for a duration of 15 minutes, repeated every three hours for five days a week. 
     
     
         7 . The system according to  claim 1 , wherein the microcontroller assembly is further configured to cause the inspiratory air flow to be delivered from the gas delivery assembly to the patient by actuation of a valve in the gas delivery assembly, wherein the valve is configured to restrict inspiratory air flow to the patient to impose negative pressure during the spontaneous patient inhalations. 
     
     
         8 . The system according to  claim 7 , wherein the valve is a positive end-expiratory pressure (PEEP) valve that is used in a reverse direction. 
     
     
         9 . The system according to  claim 1 , wherein the patient interface comprises an endrotracheal tube operatively connected to the gas delivery assembly. 
     
     
         10 . The system according to  claim 1 , wherein the one or more respiratory parameters comprise one or more measures indicative of inspiratory effort or inspiratory strength. 
     
     
         11 . The system according to  claim 1 , wherein the one or more sensors comprise pressure sensors or flow sensors. 
     
     
         12 . The system according to  claim 1  wherein the inspiratory training pressure threshold is an amount of pressure targeted during an entirety of patient inhalation to elicit delivery of inspiratory air flow. 
     
     
         13 . The system of  claim 1 , wherein the inspiratory training pressure threshold corresponds to between 30% to 60% of a maximal inhalation strength. 
     
     
         14 . The system of  claim 1 , wherein the inspiratory training pressure threshold corresponds to between 60% to 80% of a maximal inhalation strength. 
     
     
         15 . The system according to  claim 1  wherein the microcontroller assembly is further configured to determine, based at least in part on the one or more patient respiratory parameters and a machine learning model, the inspiratory training pressure threshold for the patient. 
     
     
         16 . The system according to  claim 1  wherein the microcontroller assembly is further configured to cause inspiratory air flow to be delivered to maintain the airway pressure between 1 to 80 cm of H 2 O below the baseline pressure of the gas delivery assembly while executing the inspiratory muscle strength training mode. 
     
     
         17 . The system according to  claim 1  wherein the microcontroller assembly is further configured to cause inspiratory air flow to be delivered to maintain the airway pressure between 1 to 20 cm of H 2 O below the baseline pressure of the gas delivery assembly while executing the inspiratory muscle strength training mode. 
     
     
         18 . The system according to  claim 1  wherein the microcontroller assembly is further configured to retrofit operations for delivering supply of inspiratory air flow in a processor-controlled mechanical ventilator. 
     
     
         19 . The system according to  claim 1 , wherein the microcontroller assembly is further configured to execute the inspiratory muscle strength training mode in which the microcontroller assembly causes inspiratory air flow to be delivered from the gas delivery assembly to the patient in response to the airway pressure meeting or exceeding an inspiratory training pressure threshold and, in response to the airway pressure sustaining the inspiratory training pressure threshold, temporarily supplying inspiratory air flow from the gas delivery assembly to the patient. 
     
     
         20 . The system according to  claim 1 , wherein the microcontroller assembly is further configured to:
 receive a second set of one or more patient respiratory parameters while in inspiratory muscle strength training mode;   determine, based at least in part on the second set of one or more patient respiratory parameters, a second inspiratory training pressure threshold for the patient; and   adjust the delivery of inspiratory air flow from the gas delivery assembly to the patient according to the second inspiratory training pressure threshold for the patient.   
     
     
         21 . The system according to  claim 1 , wherein the microcontroller assembly is further configured to execute a normal mode in which the microcontroller assembly causes inspiratory air flow to be delivered from the gas delivery assembly to the patient to restore the patient's breathing to a range of 4 Joules/minute to 8 Joules/minute. 
     
     
         22 . The system according to  claim 1 , wherein the microcontroller assembly is further configured to execute a normal mode operation to restore supply of inspiratory air flow from the gas delivery assembly to the patient upon completion of the inspiratory muscle strength training mode.