Pressure support system with machine delivered breaths

Patent metadata

Field	Value
Publication number	US-9259544-B2
Application number	US-201013201937-A
Country	US
Kind code	B2
Filing date	Jan 22, 2010
Priority date	Feb 25, 2009
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

A method of operating a ventilator or pressure support system that automatically determines a timed back up rate for the patient based on the patient's spontaneous breathing patterns. The aggressiveness of the determined rate increases as the patient takes less spontaneous breaths. Also, a method wherein one or more mechanisms are used to determine whether a machine breath should be issued. Each mechanism consists of a basic timing element coupled with one or more logical permits. Both the timing element and each of the one or more logical permits must be satisfied to allow the timing mechanism to trigger a machine breath.

First claim

What is claimed is:

1. A method of providing pressure support to a patient, comprising:
monitoring data relating to respiratory activity of the patient;
monitoring a timer;
determining that the timer has expired;
after determining the timer has expired, determining whether all of one or more logical permits are satisfied based on the data relating to respiratory activity of the patient; and
providing a machine breath to the patient if it is determined that all of the one or more logical permits are satisfied, wherein the one or more logical permits include a first logical permit relating to expiration of the patient and wherein the first logical permit will be determined to be satisfied if expiration of the patient is deemed to be complete, and wherein expiration of the patient is deemed to be complete in response to analyzing patient flow over a predetermined period and observing a point in time wherein both a derivative of the patient flow and an absolute value of the patient flow are less than a predetermined value.

2. The method according to claim 1 , wherein the analyzing comprises integrating the patient flow into tidal volume data, and creating a plurality of tidal volume groups each corresponding to a predetermined duration from the tidal volume data, each tidal volume group comprising a sum of the tidal volume data of the tidal volume group, wherein at any particular point in time the derivative is determined by determining an absolute value of a difference between the sum for the tidal volume group associated with the particular point in time and the sum for the tidal volume group immediately preceding the tidal volume group associated with the particular point in time, and wherein the absolute value of the patient flow at the particular point in time is equal to the absolute value of the sum for the tidal volume group associated with the particular point in time.

3. The method according to claim 2 , wherein the predetermined value is 100 ml.

4. The method according to claim 1 , further comprising integrating the patient flow into tidal volume data, and creating a plurality of tidal volume groups each corresponding to a predetermined duration from the tidal volume data, each tidal volume group comprising a sum of the tidal volume data of the tidal volume group, wherein expiration of the patient is deemed to be complete in response to both: (i) determining that an absolute value of a difference between the sum for the tidal volume group associated with a particular point in time and the sum for the tidal volume group immediately preceding the tidal volume group associated with the particular point in time is less than a predetermined value, and (ii) determining that an absolute value of the sum for the tidal volume group associated with the particular point in time is less than the predetermined value.

5. The method according to claim 4 , wherein the predetermined value is 100 ml.

6. A method of providing pressure support to a patient, comprising:
monitoring data relating to respiratory activity of the patient;
monitoring a timer;
determining that the timer has expired;
after determining the timer has expired, determining whether all of one or more logical permits are satisfied based on the data relating to respiratory activity of the patient; and
providing a machine breath to the patient if it is determined that all of the one or more logical permits are satisfied, wherein the one or more logical permits include a first logical permit relating to expiration of the patient and wherein the first logical permit will be determined to be satisfied if expiration of the patient is deemed to be complete, wherein expiration of the patient is deemed to be complete in response to analyzing patient flow over a breath, the method further comprising determining a volume throughout the breath, and wherein exhalation is deemed complete where a first portion of the volume associated with expiration matches a second portion of the volume associated with inspiration immediately preceding the first portion.

7. A method of providing pressure support to a patient, comprising:
monitoring data relating to respiratory activity of the patient;
monitoring a timer;
determining that the timer has expired;
after determining the timer has expired, determining whether all of one or more logical permits are satisfied based on the data relating to respiratory activity of the patient; and
providing a machine breath to the patient if it is determined that all of the one or more logical permits are satisfied, wherein the one or more logical permits include a first logical permit relating to expiration of the patient and wherein the first logical permit will be determined to be satisfied if expiration of the patient is deemed to be complete, wherein the timer is a conservative timer that is triggered when an inspiration to expiration transition is detected, and wherein the one or more logical permits include only the first logical permit; and
setting the timer to a timer value whenever an inspiration to expiration transition is detected, the timer value being the lesser of: (i) an average time of expiration of the patient multiplied by a constant, and (ii) a portion of a predetermined minimum breath period.

8. The method according to claim 7 , wherein the constant is 1.66 and the portion is two-thirds.

9. A method of providing pressure support to a patient, comprising:
monitoring data relating to respiratory activity of the patient;
monitoring a timer;
determining that the timer has expired;
after determining the timer has expired, determining whether all of one or more logical permits are satisfied based on the data relating to respiratory activity of the patient; and
providing a machine breath to the patient if it is determined that all of the one or more logical permits are satisfied, wherein the one or more logical permits include a first logical permit relating to expiration of the patient and wherein the first logical permit will be determined to be satisfied if expiration of the patient is deemed to be complete, wherein the timer is an aggressive timer that is triggered when an expiration to inspiration transition is detected, and wherein the one or more logical permits are a plurality of logical permits; and setting the timer to a timer value whenever an expiration to inspiration transition is detected, the timer value being the lesser of: (i) an average breath period of the patient multiplied by a constant, and (ii) a predetermined minimum breath period.

10. The method according to claim 9 , wherein the constant is 1.33.

11. A method of providing pressure support to a patient, comprising:
monitoring data relating to respiratory activity of the patient;
monitoring a timer;
determining that the timer has expired;
after determining the timer has expired, determining whether all of one or more logical permits are satisfied based on the data relating to respiratory activity of the patient; and
providing a machine breath to the patient if it is determined that all of the one or more logical permits are satisfied, wherein the one or more logical permits include a first logical permit relating to expiration of the patient and wherein the first logical permit will be determined to be satisfied if expiration of the patient is deemed to be complete, wherein the timer is an aggressive timer that is triggered when an expiration to inspiration transition is detected, and wherein the one or more logical permits are a plurality of logical permits, wherein the plurality of logical permits includes a second logical permit relating to a percent of timed breaths over a predetermined number of prior breaths, and where

Assignees

• Kane Michael T
• Matthews Gregory
• Shelly Benjamin Irwin
• Ressler Heather Dawn
• Koninkl Philips Nv

Inventors

• Kane Michael T
• Matthews Gregory
• Shelly Benjamin Irwin
• Ressler Heather Dawn

Classifications

• A61M16/00 Primary

  Devices for influencing the respiratory system of patients by gas treatment, e.g. ventilators (iron lungs A61H31/02); Tracheal tubes · CPC title

• A61M2016/0015

  inhalation detectors · CPC title

• A61M16/026 Primary

  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 title