System and method of monitoring respiratory events

• US 8,025,052 B2
• Filed: 11/17/2006
• Issued: 09/27/2011
• Est. Priority Date: 11/21/2005
• Status: Active Grant

• Current Assignee: Philips RS North America LLC (Koninklijke Philips N.V.)
• Original Assignee: RIC INVESTMENTS LLC (Koninklijke Philips N.V.)
• Inventors: Baloa, Leonardo A., Matthews, Greg
• Primary Examiner(s): Yu; Justine
• Assistant Examiner(s): OSTRUP, CLINTON T
• Application Number:
  US11/600,981
• Publication Number:
  US 20070113849A1
• Time in Patent Office: 1,775 Days
• Field of Search: 128/200.24, 128/204.21, 128/204.22, 128/204.23, 128/920, 128/898, 128/204.24, 128/204.26, 600/529, 600/534
• US Class Current: 128/204.21
• CPC Class Codes: A61M 16/0051 with alarm devices
• CPC Class Codes: A61M 16/0066 Blowers or centrifugal pumps
• CPC Class Codes: A61M 16/0069 the speed thereof being controlled by respiratory parameters, e.g. by inhalation
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• 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 2016/0036 in the breathing tube and used in both inspiratory and expiratory phase
• CPC Class Codes: A61M 2016/0042 in the expiratory circuit
• CPC Class Codes: A61M 2230/40 Respiratory characteristics
• CPC Class Codes: A61M 2230/42 Rate

Abstract

A system and method of monitoring a patient, that in one embodiment, comprises determining a flow of gas generated by respiration of the patient, identifying a respiratory event entry and a respiratory event exit based on the flow of gas generated by respiration of the patient, and identifying a respiratory event when the identification of the respiratory event entry is followed by the identification of respiratory event exit.

Claims

1. A method of monitoring a patient, the method comprising:

monitoring flow of a flow of gas generated by respiration of a patient;

detecting occurrence of a respiratory event entry based on peak values of flow during inspirations by such a patient, the detection of the occurrence of the respiratory event entry being made responsive to a decline in the peak values of flow across a first set of successive inspirations;

detecting occurrence of a respiratory event exit based on peak values of flow during inspirations by such a patient subsequent to the first set of successive inspirations, the detection of the occurrence of the respiratory event exit being made responsive to an increase in the peak values of flow across a second set of successive inspirations; and

identifying a respiratory event responsive to the detection of the respiratory event entry being followed by the detection of the respiratory event exit.

2. The method of claim 1, wherein monitoring the flow of the gas comprises generating a signal that corresponds to the flow of the gas, and wherein identifying the respiratory event entry comprises monitoring a shape of the signal during an inspiration.

3. The method of claim 1, wherein the second set of successive inspirations includes an inspiration from the first set of inspirations.

4. The method of claim 1, wherein detecting a respiratory event entry, detecting a respiratory event exit, or both includes comparing the peak values of flow during the first series of inspirations and/or the second series of inspirations to at least a portion of a template.

5. The method of claim 1, wherein detecting the respiratory event exit comprises detecting a change in shape of the flow of the gas during consecutive inspirations in the second series of inspirations.

6. The method of claim 1, further comprising adjusting at least one aspect of treatment received by the patient based on the identification of a respiratory event.

7. The method of claim 6, wherein the aspect of treatment comprises a pressure of gas delivered to an airway of the patient, an operation performed by a pressure generating device providing a flow of gas to the patient, or both.

8. A method of monitoring a patient, the method comprising:

monitoring flow of gas generated by respiration of the patient;

detecting a respiratory event based on peak values of flow during a series of inspirations that includes a first set of successive inspirations and a second set of successive inspirations, the detection of the occurrence of the respiratory event being made responsive to first a decline in the peak values of flow across the first set of successive inspirations in the series of inspirations and then an increase in the peak values of flow across the second set of successive inspirations in the series of inspirations; and

adjusting one or more aspects of treatment received by the patient based on the identification of the respiratory event.

9. The method of claim 8, wherein the one or more aspects of treatment comprises a pressure of gas delivered to the airway of the patient.

10. A patient treatment system that delivers a pressurized flow of breathable gas to an airway of a patient, the system comprising:

a sensor monitor that monitors flow of a flow of gas generated by respiration of a patient;

an event entry module adapted to detect occurrences of respiratory event entries based on peak values of the flow monitored by the sensor, the event entry module being configured to detect an occurrence of a respiratory event entry responsive to a decline in the peak values of flow across a first set of successive inspirations;

an event exit module adapted to detect occurrences of respiratory event exits that are different from the entry events based on peak values of the flow monitored by the sensor, the detection of an occurrence of a respiratory event exit being made responsive to an increase in the peak values of flow across a second set of successive inspirations, the second set of successive inspirations corresponding to a period in time that is subsequent to a period of time corresponding to the first set of successive inspirations; and

a respiratory event module adapted to identify a respiratory event responsive to a detection of a respiratory event entry being followed by a detection of a respiratory event exit.

11. The patient treatment system of claim 10, wherein the sensor is adapted to generate a signal that corresponds to the flow of the gas, and wherein the event entry module monitors a shape of the signal during an inspiration to detect occurrences of respiratory event entries.

12. The patient treatment system of claim 10, wherein the event entry module is adapted to identify a change in shape of the flow of the gas during successive inspirations to detect respiratory event entries.

13. The patient treatment system of claim 12, wherein the event entry module is adapted to identify a change in shape of the flow of the gas during successive inspirations to detect respiratory event entries.

14. The patient treatment system of claim 10, wherein the event exit module is adapted to identify a change of shape of the flow of the gas during consecutive inspirations.

15. The patient treatment system of claim 10, further comprising a treatment adjustment module that adjusts one or more aspects of treatment received by the patient, an operation performed by a pressure generating device providing a flow of gas to the patient, or both based on the identification of a respiratory event.

16. The patient treatment system of claim 15, wherein the treatment adjustment module adjusts a pressure of gas delivered to the airway of the patient with the respiratory event module identifies a respiratory event.

17. The patient treatment system of claim 10, wherein (a) the event entry module is adapted to detect respiratory event entries by comparing peak values of flow during inspirations to at least a portion of a template, (b) the event exit module is adapted to detect respiratory event exits by comparing peak values of flow during inspirations at least a portion of a template, or (c) both (a) and (b).