METHODS AND SYSTEMS FOR AN OPTIMIZED PROPORTIONAL ASSIST VENTILATION

• US 20130284172A1
• Filed: 04/27/2012
• Published: 10/31/2013
• Est. Priority Date: 04/27/2012
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Nellcor Puritan Bennett LLC (Medtronic Plc)
• Inventors: Doyle, Peter, Jafari, Mehdi M.
• Granted Patent: US 9,993,604 B2
• Time in Patent Office: Days
• US Class Current: 128/204.23
• CPC Class Codes: A61M 16/0051 with alarm devices
• CPC Class Codes: A61M 16/0063 Compressors
• CPC Class Codes: A61M 16/026 specially adapted for predicting, e.g. for determining an information representative of a flow limitation during a ventilation cycle by using a root square technique or a regression analysis
• CPC Class Codes: A61M 16/0833 T- or Y-type connectors, e.g. Y-piece
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/0033 electrical
• CPC Class Codes: A61M 2205/502 User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 2230/46 Resistance or compliance of the lungs

Abstract

This disclosure describes systems and methods for providing an optimized proportional assist breath type during ventilation of a patient. The disclosure describes a novel breath type that delivers a target airway pressure calculated based on a desired patient effort range to a triggering patient.

Claims

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

retrieving a desired patient effort range;

estimating an initial percent support setting based on the desired patient effort range;

calculating a target airway pressure based at least on the initial percent support setting; and

delivering the target airway pressure to a patient.

2. The method of claim 1, further comprising:

calculating a current patient effort;

determining that the current patient effort is outside of the desired patient effort range; and

calculating an adjusted percent support setting based on the step of determining that the current patient effort is outside of the desired patient effort range.

3. The method of claim 2, further comprising:

calculating an adjusted target airway pressure based at least on the adjusted percent support setting; and

delivering the adjusted target airway pressure to the patient.

4. The method of claim 3, further comprising:

calculating the current patient effort;

determining that the current patient effort is within the desired patient effort range; and

delivering a previously delivered target airway pressure to the patient based on the step of determining that the current patient effort is within the desired patient effort range.

5. The method of claim 4, further comprising:

receiving a desired treatment metric range from an operator;

determining the desired patient effort range based on the desired treatment metric range;

determining that a current treatment metric is not within the desired treatment metric range; and

adjusting at least one ventilator parameter until the current treatment metric is within the desired treatment metric range.

6. The method of claim 5, wherein the at least one ventilator parameter is at least one of oxygen percentage, rise time, trigger sensitivity, peak flow rate, peak inspiratory pressure, tidal volume, and PEEP.

7. The method of claim 5, wherein the desired treatment metric range is at least one of a trend and a weighted combination of at least one of RSBI, SpO₂, P₁₀₀, Oxygen index, ETCO₂, tidal volume, VCO₂, respiratory rate, spontaneous I:

E ratio, and a minute volume.

8. The method of claim 5, wherein the desired treatment metric range is a range of at least one of RSBI, SpO₂, P₁₀₀, Oxygen index, ETCO₂, tidal volume, VCO₂, respiratory rate, spontaneous I:

E ratio, and a minute volume.

9. The method of claim 1, further comprising:

receiving a desired treatment metric range from an operator; and

determining the desired patient effort range based on the desired treatment metric range.

10. The method of claim 1, wherein the target airway pressure is calculated utilizing a following equation:

Target Pressure(t)=k[E_p∫

Q_pdt+Q_pR_p].

11. The method of claim 1, wherein the desired patient effort range is received from at least one of an operator via operator selection from a group of desired patient effort ranges, the operator via an input of a desired patient effort parameter, the ventilator calculated based on at least one of an at least one monitored patient parameter and ventilator parameters, and the ventilator via a selection from a group of predetermined patient efforts ranges based on at least one of the at least one monitored patient parameter and the ventilator parameters.

12. The method of claim 1, wherein the desired patient effort range is from about 5 cm of H₂O to about 10 cm of H₂0.

13. 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;

one or more sensors operatively coupled to at least one of the pressure generating system, the patient, and the ventilation tubing system, wherein the one or more sensors generate output indicative of an inspiration flow;

a support module that estimates an initial percent support setting based at least on a desired patient effort range and calculates at least one adjusted percent support setting based at least on the desired patient effort range, and a current patient effort; and

an OPA module, the OPA module calculates an initial target airway pressure based at least on the initial percent support setting, calculates at least one adjusted target airway pressure based at least on an adjusted percent support setting, and utilizes the output indicative of the inspiration flow to determine a patient trigger for delivery of a breath to the patient.

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

a treatment module, the treatment module determines the desired patient effort range based on a desired treatment metric, range received from operator input and adjusts at least one ventilator parameter if a current treatment metric is not within the desired treatment metric range while the current patient effort is within the desired patient effort range for at least two consecutive breaths.

15. The ventilator system of claim 14, wherein the at least one ventilator parameter is at least one of oxygen percentage, rise time, trigger sensitivity, peak flow rate, peak inspiratory pressure, tidal volume, and PEEP.

16. The ventilator system of claim 14, further comprising a display that displays at least one of the current patient effort, the desired patient effort range, the desired treatment metric range, a current treatment metric range, a RSBI, a SpP₂, a P100, a tidal volume, a VCO₂, a respiratory rate, a spontaneous I:

E volume, a minute volume, the initial percent support setting, and the adjust percent support setting.

17. The ventilator system of claim 14, wherein the support module calculates the at least one adjusted percent support setting when the current patient effort is outside of the desired patient effort range.

18. A computer-readable medium having computer-executable instructions for performing a method of ventilating a patient with a ventilator, the method comprising:

repeatedly retrieving a desired patient effort range;

estimating an initial percent support setting based on the desired patient effort range;

repeatedly calculating a target airway pressure based at least on the initial percent support setting; and

repeatedly delivering the target airway pressure to a patient.

19. The method of claim 18, further comprising:

repeatedly calculating a current patient effort;

repeatedly determining if the current patient effort is above the desired patient effort range; and

repeatedly calculating an adjusted percent support setting that is greater than the initial percent support setting.

20. The method of claim 18, further comprising:

repeatedly calculating a current patient effort;

repeatedly determining if the current patient effort is below the desired patient effort range; and

repeatedly calculating an adjusted percent support setting that is less than the initial percent support setting.

21. A ventilator system, comprising:

means for retrieving a desired patient effort range;

means for estimating an initial percent support setting based on the desired patient effort range;

means for calculating a target airway pressure based at least on the initial percent support setting; and

means for delivering the target airway pressure to a patient.