Systems and methods for triggering and cycling a ventilator based on reconstructed patient effort signal

A ventilation system, the ventilation system comprising:

• a processor communicably coupled to a computer readable medium, wherein the computer readable medium includes instructions executable by the processor to:
• receive a pressure value;
• determine a net flow based on an inlet flow value and an outlet flow value;
• use a relationship between a first value related to the pressure, a second value related to the net flow, and a third value related to patient effort to calculate an estimated patient effort, wherein the third value related to patient effort represents at least one unknown value, and wherein the estimate of patient effort is determined based on the unknown value being characterized by a smooth signal;
• update an interim value used to calculate a previous computed patient effort based at least in part on the estimated patient effort, wherein the interim value is represented by a composite parameter that does not directly correspond to a particular respiratory parameter;
• calculate a computed patient effort based at least in part on the updated interim value;
• and
• initiate a ventilation cycle based at least in part on the computed patient effort.

A patient ventilator, the ventilator comprising:

• a gas inlet;
• a gas outlet;
• a tube coupling the gas inlet and the gas outlet;
• a pressure sensor, wherein the pressure sensor is operable to provide a measured pressure indicating a pressure in the tube;
• a first flow sensor, wherein the first flow sensor is operable to provide an inlet flow value indicating a flow associated with the gas inlet;
• a second flow sensor, wherein the second flow sensor is operable to provide an outlet flow value indicating a flow associated with the gas outlet;
• and
• a processor communicably coupled to a computer readable medium, wherein the computer readable medium includes instructions executable by the processor to:
• receive the measured pressure;
• calculate a net flow based at least in part on an inlet flow value and an outlet flow value;
• use a relationship between a first value related to the measured pressure, a second value related to the net flow and a third value related to patient effort to provide an estimated patient effort, wherein the third value related to patient effort represents at least one unknown value, and wherein the estimate of patient effort is determined based on the unknown value being characterized by a smooth signal;
• update an interim value used to calculate a previous computed patient effort based at least in part on the estimated patient effort, wherein the interim value is represented by a composite parameter that does not directly correspond to a particular respiratory parameter;
• calculate a computed patient effort based at least in part on the updated interim value;
• and
• initiate a ventilation cycle based at least in part on the computed patient effort.