Filtering patient signal also for ventilation artifacts

• US 10,039,497 B2
• Filed: 08/30/2017
• Issued: 08/07/2018
• Est. Priority Date: 09/24/2012
• Status: Active Grant

• Current Assignee: Physio-Control Incorporated (Stryker Corporation)
• Original Assignee: Physio-Control Incorporated (Stryker Corporation)
• Inventors: Sullivan, Joseph L., Walker, Robert G.
• Primary Examiner(s): Holmes, Rex R
• Application Number:
  US15/691,518
• Publication Number:
  US 20170360375A1
• Time in Patent Office: 342 Days
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/0836 Measuring rate of CO2 production
• CPC Class Codes: A61B 5/087 Measuring breath flow
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/361 Detecting fibrillation
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/7207 of noise induced by motion artifacts
• CPC Class Codes: A61B 5/721 using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured
• CPC Class Codes: A61B 5/7217 of noise originating from a therapeutic or surgical apparatus, e.g. from a pacemaker
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61H 2201/501 connected to external computer devices or networks
• CPC Class Codes: A61H 2201/5043 Displays
• CPC Class Codes: A61H 2201/5097 wireless
• CPC Class Codes: A61H 2230/045 used as a control parameter for the apparatus
• CPC Class Codes: A61H 2230/206 used as a control parameter for the apparatus
• CPC Class Codes: A61H 2230/208 used as a control parameter for the apparatus
• CPC Class Codes: A61H 2230/305 used as a control parameter for the apparatus A61H2230/045 takes precedence
• CPC Class Codes: A61H 2230/505 used as a control parameter for the apparatus
• CPC Class Codes: A61H 31/005 : with feedback for the user
• CPC Class Codes: A61M 16/0057 : Pumps therefor
• CPC Class Codes: A61M 16/0069 : the speed thereof being controlled by respiratory parameters, e.g. by inhalation
• CPC Class Codes: A61M 16/021 : operated by electrical means A61M16/202 – A61M16/205 take precedence
• CPC Class Codes: A61N 1/39044 : in combination with cardiopulmonary resuscitation [CPR] therapy
• CPC Class Codes: A61N 1/3925 : Monitoring; Protecting

Abstract

In embodiments, an external medical device is intended to care for a patient. If it receives an input that signifies that ventilation artifact is present in a signal of the patient, it transmits a corrective signal responsive to the received input. In further embodiments, a patient signal is received, which is generated from a patient while the patient is or was receiving chest compressions at a frequency Fc, and also receiving ventilations at frequency Fv. At least one filter mechanism may be applied to the patient signal to substantially remove artifacts at a) frequency Fc, b) a higher harmonic of frequency Fc, and c) a third frequency substantially equaling frequency Fc plus or minus frequency Fv, while substantially passing other frequencies between them. As a result, the patient signal can be cleaner, for diagnosing the patient'"'"'s state more accurately.

Claims

1. A system for treating a patient, comprising:

a mechanical chest compression device configured to deliver chest compressions to the patient at a frequency Fc;

a ventilator configured to deliver ventilations to the patient at a frequency Fv; and

an external device having a housing and a processor within the housing, the processor configured to;

receive a signal from the patient, and

apply at least one filter mechanism to the patient signal to substantially remove from the patient signal artifacts at the frequency Fc, at a higher harmonic of the frequency Fc, and at a third frequency substantially equaling the frequency Fc minus the frequency Fv, while substantially passing other frequencies between the frequency Fc and the higher harmonic, and between the frequency Fc and the third frequency.

2. The system of claim 1, in which

the patient signal is an ECG signal.

3. The system of claim 1, in which

the patient signal is an impedance signal.

4. The system of claim 1, further comprising:

an energy storage module within the housing for storing an electrical charge, and

a defibrillation port for guiding via electrodes the stored electrical charge to the patient.

5. The system of claim 1, further comprising:

a display in connection with the housing.

6. The system of claim 5, in which

the processor is further configured to cause the display to present visually to a user the patient signal with the artifacts substantially removed.

7. The system of claim 1, further comprising:

a memory, and

in which the processor is further configured to store in the memory the patient signal with the artifacts substantially removed.

8. The system of claim 1, in which

the filter mechanism substantially rejects additionally at least two more frequencies that are additional higher harmonics of the frequency Fc.

9. The system of claim 1, in which

the frequency Fc is looked up from an inputted identification of the mechanical chest compression device.

10. The system of claim 1, in which

an indication of the frequency Fc is received by the processor.

11. The system of claim 1, in which

the processor is further configured to detect the chest compressions.

12. The system of claim 1, in which

the frequency Fv is looked up from an inputted identification of the ventilator.

13. The system of claim 1, in which

an indication of the frequency Fv is received by the processor.

14. The system of claim 1, in which

the processor is further configured to detect the ventilations.

15. The system of claim 1, in which

the filter mechanism comprises a comb filter, a plurality of notch filters, or both.

16. The system of claim 15, in which

the filter mechanism has a Q value of no less than 4.

17. The system of claim 15, in which

the plurality of notch filters has a 3 dB notch width of no more than approximately 0.5 Hz.

18. The system of claim 1, in which

the filter mechanism includes a non-adaptive filter.

19. The system of claim 1, in which

the processor is configured to apply the filter mechanism responsive to an input by a user.

20. The system of claim 1, in which

the processor is further configured to monitor an impedance signal of the patient, and to further detect return of spontaneous circulation by applying a signal-averaging filter to the impedance signal.