Methods and systems for ventilation with unknown exhalation flow and exhalation pressure

• US 9,492,629 B2
• Filed: 02/14/2013
• Issued: 11/15/2016
• Est. Priority Date: 02/14/2013
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Sanchez, Gabriel, Nakai, Richard, Carter, Danis, Dong, Nancy
• Primary Examiner(s): Vasat, Peter S
• Application Number:
  US13/767,750
• Publication Number:
  US 20140224250A1
• Time in Patent Office: 1,370 Days
• Field of Search: 128/203.14, 128/204.21, 128/204.23, 128/200.24, 128/202.22, 128/203.12, 128/204.18, 128/204.26, 128/205.24
• US Class Current: 1/1
• CPC Class Codes: A61M 16/0063 Compressors
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 16/161 with means for measuring the humidity
• CPC Class Codes: A61M 16/204 used for inhalation control
• CPC Class Codes: A61M 16/205 used for exhalation control
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2016/0042 in the expiratory circuit
• CPC Class Codes: A61M 2205/16 with back-up system in case of failure
• CPC Class Codes: A61M 2205/17 with redundant control systems
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2205/505 Touch-screens; Virtual keyboard or keypads; Virtual buttons; Soft keys; Mouse touches

Abstract

This disclosure describes systems and methods for providing novel back-up ventilation. Further, this disclosure describes systems and methods for delivering ventilation when exhalation pressure and/or exhalation flow are unknown or unreliable by the ventilator.

Claims

1. A method for ventilating a patient with a ventilator, comprising:

monitoring inspiratory flow, expiratory flow, and expiratory pressure during ventilation of the patient with the ventilator;

monitoring features associated with at least one of an expiratory flow sensor, an expiratory pressure sensor, and a main driver;

delivering ventilation for any breath type during a predetermined or a selected mode of ventilation based at least on the expiratory flow and the expiratory pressure,

wherein the predetermined or the selected mode of ventilation includes a spontaneous mode, an assist mode, or a mandatory mode;

determining, with the ventilator, a malfunction in at least one of the expiratory flow sensor, the expiratory pressure sensor, and the main driver that makes at least one of the expiratory flow and the expiratory pressure unreliable based on the features associated with at least one of the expiratory flow sensor, the expiratory pressure sensor, and the main driver;

in response to the malfunction, automatically ceasing the delivering of the predetermined or the selected mode of ventilation based at least on the expiratory flow and the expiratory pressure and instead automatically delivering an exhalation backup ventilation mode based on at least one of the inspiratory flow and an inspiratory pressure by the ventilator;

controlling pressure delivered during the ventilation based at least on controlling an exhalation valve;

controlling the exhalation valve with the main driver;

in response to the malfunction, controlling the exhalation valve with a backup driver includes;

inputting the inspiratory flow and the inspiratory pressure during inspiration into an inspiratory control algorithm; and

inputting the inspiratory flow and the inspiratory pressure during exhalation into an expiratory control algorithm.

2. The method of claim 1, further comprising:

in response to the malfunction, determining an inspiratory phase;

wherein the pressure delivered to the patient is a set inspiration pressure during the inspiratory phase.

3. The method of claim 1, further comprising:

in response to the malfunction, determining an exhalation phase;

wherein the pressure delivered to the patient is a set PEEP during the exhalation phase.

4. The method of claim 1, wherein the main driver is malfunctioning.

5. The method of claim 4, wherein the exhalation valve relieves an over pressure established during inhalation to obtain a desired inspiration pressure.

6. The method of claim 1, wherein the expiratory control algorithm subtracts the inspiratory pressure from a set PEEP.

7. The method of claim 1, further comprising:

in response to the malfunction,

displaying use of the exhalation backup ventilation mode.

8. The method of claim 1, wherein the features include changes in at least one of voltages, temperatures, wattages, coefficients, and humidity.

9. A ventilator system comprising:

a pressure generating system adapted to generate a flow of breathing gas;

a ventilation tubing system including a patient interface for connecting the pressure generating system to a patient;

an exhalation valve connected to the ventilation tubing system;

a plurality of sensors operatively coupled to at least one of the pressure generating system, the patient, and the ventilation tubing system, wherein the plurality of sensors include an inspiratory pressure sensor for monitoring inspiratory pressure, an inspiratory flow sensor for monitoring inspiratory flow, an expiratory pressure sensor for monitoring exhalation pressure, and an expiratory flow sensor for monitoring expiratory flow;

a main driver, the main driver controls the exhalation valve to deliver ventilation for any breath type during at least one of an assist mode, a spontaneous mode, and mandatory mode of ventilation to the patient based at least on at least one of the exhalation pressure and the expiratory flow monitored by the plurality of sensors;

a backup driver, the backup driver controls the exhalation valve to deliver backup ventilation to the patient during an exhalation backup ventilation mode based on at least one of the inspiration pressure and the inspiration flow monitored by the plurality of sensors; and

a controller, the controller determines a malfunction in at least one of the expiratory flow sensor, the expiratory pressure sensor, and the main driver making the expiratory flow and the expiratory pressure unreliable based on features associated with at least one of the expiratory flow sensor, the expiratory pressure sensor, and the main driver and switches from the main driver to the backup driver in response to the malfunction;

wherein the backup driver controls the exhalation valve during inspiration by utilizing an inspiratory control algorithm; and

wherein the backup driver controls the exhalation valve during exhalation by utilizing an exhalation control algorithm.

10. The ventilator system of claim 9, wherein the backup driver is on a circuit isolated from the main driver.

11. The ventilator system of claim 9, wherein the main driver is a differential driver.

12. The ventilator system of claim 9, wherein the backup driver is a pulse modulated driver.

13. The ventilator system of claim 9, further comprising:

a display that displays utilization of the exhalation backup ventilation mode.

14. The ventilator system of claim 9, wherein in response to the malfunction, the controller determines delivery of inspiration and exhalation based on a set inspiratory time and respiration rate;

wherein a pressure delivered to the patient is a set PEEP during exhalation, and

wherein the pressure delivered to the patient is a set inspiration pressure during inspiration.

15. The ventilator system of claim 9, wherein the controller detects the malfunction in the main driver.

16. The ventilator system of claim 9, wherein the expiratory control algorithm subtracts the inspiratory pressure from a set PEEP.

17. The ventilator system of claim 9, wherein the features include changes in at least one of voltages, temperatures, wattages, coefficients, and humidity.

18. The ventilator system of claim 9, wherein the exhalation valve is controlled to relieve an over pressure established during inhalation to obtain a desired inspiration pressure.

19. A ventilatory system, comprising:

at least one processor; and

at least one non-transitory memory, communicatively coupled to the at least one processor and containing instructions that cause the ventilatory system to;

monitor inspiratory flow, inspiratory pressure, expiratory flow, and expiratory pressure during ventilation of a patient based on data from a plurality of sensors;

monitor changes in at least one of voltages, temperatures, wattages, coefficients, and humidity in at least one component of the ventilatory system;

deliver the ventilation for any breath type during at least one of a spontaneous mode, an assist mode, or a mandatory mode of ventilation based at least on the expiratory flow and the expiratory pressure;

determine a malfunction that makes at least one of the expiratory flow and the expiratory pressure unreliable, wherein the malfunction is determined based on the changes;

in response to the malfunction, switching the mode of ventilation from being based at least on the expiratory flow and the expiratory pressure to an exhalation backup ventilation mode that is based on at least one of the inspiratory flow and the inspiratory pressure; and

in response to the malfunction, displaying the malfunction;

controlling a pressure delivered during the ventilation based at least on controlling an exhalation valve;

controlling the exhalation valve with a main driver;

in response to the malfunction, controlling the exhalation valve with a backup driver;

wherein the step of controlling the exhalation valve with the backup driver includes;

inputting the inspiratory flow and the inspiratory pressure during inspiration into an inspiratory control algorithm; and

inputting the inspiratory flow and the inspiratory pressure during exhalation into an expiratory control algorithm.