Systems and methods for wireless feedback during ventilation

• US 10,137,265 B2
• Filed: 05/16/2012
• Issued: 11/27/2018
• Est. Priority Date: 05/23/2011
• Status: Active Grant

• Current Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Original Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Inventors: Freeman, Gary A., Silver, Annemarie, Herken, Ulrich, Cloutier, Jon P.
• Primary Examiner(s): Jang, Christian
• Assistant Examiner(s): Alter, Mitchell E
• Application Number:
  US13/473,002
• Publication Number:
  US 20120302910A1
• Time in Patent Office: 2,386 Days
• Field of Search: 600538, 12820513
• CPC Class Codes: A61H 2201/5071 Pressure sensors
• CPC Class Codes: A61H 2201/5084 Acceleration sensors
• CPC Class Codes: A61H 2230/205 partial CO2-value
• CPC Class Codes: A61H 2230/207 partial O2-value
• CPC Class Codes: A61H 2230/42 Rate
• CPC Class Codes: A61H 2230/80 Weight
• CPC Class Codes: A61H 31/00 Artificial respiration or heart stimulation, e.g. heart massage artificial respiration by treatment with gas or air, e.g. mouth-to-mouth respiration A61M16/00; applying electric currents by contact electrodes for stimulation, e.g. heart pace-makers A61N1/36 ; teaching or training models, demonstration models for medical purposes G09B23/288
• CPC Class Codes: A61H 31/005 with feedback for the user
• CPC Class Codes: A61M 16/0003 Accessories therefor, e.g. sensors, vibrators, negative pressure
• CPC Class Codes: A61M 16/0069 the speed thereof being controlled by respiratory parameters, e.g. by inhalation
• CPC Class Codes: A61M 16/0078 Breathing bags
• CPC Class Codes: A61M 16/0084 self-reinflatable by elasticity, e.g. resuscitation squeeze bags
• CPC Class Codes: A61M 16/021 operated by electrical means A61M16/202 – A61M16/205 take precedence
• CPC Class Codes: A61M 16/0858 Pressure sampling ports
• CPC Class Codes: A61M 2016/0024 with an on-off output signal, e.g. from a switch
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/003 with a flowmeter
• CPC Class Codes: A61M 2016/0036 in the breathing tube and used in both inspiratory and expiratory phase
• CPC Class Codes: A61M 2205/054 with electrotherapy
• CPC Class Codes: A61M 2205/15 Detection of leaks
• CPC Class Codes: A61M 2205/332 : Force measuring means
• CPC Class Codes: A61M 2205/3569 : sublocal, e.g. between console and disposable
• CPC Class Codes: A61M 2205/3592 : using telemetric means, e.g. radio or optical transmission
• CPC Class Codes: A61M 2205/505 : Touch-screens; Virtual keyboard or keypads; Virtual buttons; Soft keys; Mouse touches
• CPC Class Codes: A61M 2205/581 : by audible feedback
• CPC Class Codes: A61M 2205/583 : by visual feedback
• CPC Class Codes: A61M 2205/587 : Lighting arrangements
• CPC Class Codes: A61M 2230/432 : partial CO2 pressure (P-CO2)
• CPC Class Codes: A61M 2230/46 : Resistance or compliance of the lungs
• CPC Class Codes: A61N 1/3987 : characterised by the timing or triggering of the shock
• CPC Class Codes: G16H 20/40 : relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture

Abstract

Systems and methods regarding ventilation of a patient, such as a victim at the scene of an emergency are described herein.

Claims

1. A system for providing feedback on delivery of cardiopulmonary resuscitation (CPR), the system comprising:

a manual patient ventilation unit defining an airflow path, the unit arranged so that when the unit is applied to a patient, the airflow path is in fluid communication with the patients airway, the patient ventilation unit comprising;

a ventilation bag configured to enable manual ventilation of the patient by a rescuer;

at least one first sensor in the airflow path positioned to sense the presence of ventilation airflow and measure a gas flow rate in the airflow path; and

at least one second sensor in the airflow path positioned to sense gas pressure in the airflow path;

at least one chest compression sensor configured to detect and measure compression information based on chest compressions applied to the patient; and

a feedback unit separate from the manual patient ventilation unit comprising a processor arranged to;

wirelessly receive data generated by the at least one first sensor and the at least one second sensor;

determine one or more ventilation quality parameters based at least in part on a gas flow volume calculated based on the sensed gas flow rate and gas pressures;

receive compression data generated by the at least one chest compression sensor;

determine one or more chest compression parameters based at least in part on the measured compression information; and

provide both ventilation feedback and chest compression feedback to a rescuer, the ventilation feedback comprising the one or more ventilation quality parameters and instructions for performing ventilations based upon a comparison of the ventilation quality parameters with a ventilation protocol comprising ranges of predetermined acceptable values for administering ventilations to the patient and the chest compression feedback comprising the one or more chest compression parameters and instructions for performing chest compressions based upon a comparison of the chest compression parameters with a chest compression protocol comprising ranges of predetermined acceptable values for administering chest compressions to the patient,

wherein the ventilation quality parameters comprise one or more of tidal volume, minute volume, end-inspiratory pressure, and maximum ventilation pressure.

2. The system of claim 1, further comprising circuitry configured for delivery of electromagnetic stimulation to the patient.

3. The system of claim 1, wherein the ventilation bag comprises a flexible reservoir containing ventilatory gases configured to enable manual ventilation of the patient by a rescuer squeezing the flexible reservoir.

4. The system of claim 1, wherein the ventilation bag is configured to enable manual ventilation of the patient by a rescuer pressing a switch of an electromechanically-controlled ventilator.

5. The system of claim 1, wherein the one or more ventilation quality parameters include an indicator indicative of a ventilation being delivered during a compression cycle.

6. The system of claim 1, further comprising a capnometer in the airflow path positioned to sense the concentration of CO₂ in the airflow path.

7. The system of claim 1, further comprising an oxygen sensor in the airflow path positioned to sense the concentration of O₂ in the airflow path.

8. The system of claim 1, wherein:

the processor is configured to compute end-tidal CO₂ values; and

the feedback unit is configured to provide an indication to increase ventilation if the end-tidal CO₂ value is outside of a first range and to decrease ventilation if the end-tidal CO₂ value is outside of a second range.

9. The system of claim 1, wherein:

the processor is further configured to compute volumetric CO₂ values; and

the feedback unit is configured to provide an indication to increase ventilation if the volumetric CO₂ value is outside of a first range and to decrease ventilation if the volumetric CO₂ value is outside of a second range.

10. The system of claim 1, wherein the processor is further configured to compute lung compliance.

11. The system of claim 10, wherein the processor is further configured to detect at least one of the following conditions based, at least in part, on the lung compliance measurements:

barotrauma, hemothorax, pneumothorax, intubation in the mainstem, flail chest, or pediatric lung distension.

12. The system of claim 10 wherein the feedback unit is configured to provide feedback related to tidal volume.

13. The system of claim 1, wherein:

the processor is configured to compute a difference in in-flow volume and out-flow volume; and

the feedback unit is configured to provide feedback related one or more of ventilation release and ventilation seal.

14. The system of claim 1, wherein:

the processor is configured to identify conditions when a negative pressure occurs during in-flow of air; and

the feedback unit is configured to provide feedback regarding the existence of a spontaneous breath when a negative pressure occurs during in-flow of air.

15. The system of claim 1, wherein the feedback comprises feedback that communicates to the rescuer an appropriate volume for providing ventilation to the patient.

16. The system of claim 1, wherein the feedback unit comprises a visual feedback mechanism for providing information to a rescuer regarding delivery of ventilation comprising a plurality of lights arranged to indicate, based on which lights of the plurality of lights are activated, whether excessive ventilation, too little ventilation, or an appropriate amount of ventilation is being provided to the victim.

17. The device of claim 1, wherein the feedback unit is configured to provide an instruction pertaining to varying the delivered tidal volume.

18. The system of claim 1, wherein the feedback unit comprises a visual feedback mechanism for providing information to a rescuer regarding delivery of ventilation comprising a ventilation timer providing information about respiratory rate.

19. The system of claim 1, wherein the feedback unit comprises a visual feedback mechanism for providing information to a rescuer regarding delivery of ventilation comprising a ventilation timer providing information about elapsed time between ventilation events.

20. The system of claim 1, wherein the feedback unit comprises a device configured to form audible prompts and the feedback comprises audible prompts.

21. The system of claim 1, wherein the feedback unit comprises a device configured to form audible prompts and the feedback comprises verbal instructions.

22. The system of claim 1, wherein the feedback unit comprises a device configured to form audible prompts and the feedback comprises one or more tones.

23. The system of claim 1, wherein the feedback unit comprises a graphical display and the feedback comprises visual feedback for the one or more ventilation parameters and the one or more chest compression parameters provided on the graphical display.

24. The system of claim 1, wherein the feedback unit comprises a graphical display and the feedback comprises a visual representation of a shape with demarcations indicating specific tidal volume values, wherein the volume fills during the ventilation.

25. The system of claim 24, wherein the visual representation further comprises a visual marker indicative of a target tidal volume.

26. The system of claim 1, wherein the processor is further configured to determine compliance features and determine a patient state based on the compliance features.

27. The system of claim 26, wherein the patient state comprises a state selected from the group consisting of barotraumas, hemothorax, pneumothorax, intubation in mainstem, flail chest, and pediatric lung overdistension.

28. The system of claim 1, wherein the processor is further configured to detect a mask leak.

29. The system of claim 1, wherein the processor is further configured to compare pressure data from the at least one second sensor and flow data from the at least one first sensor at multiple points in time to compute an estimate of lung compliance.

30. The system of claim 29, wherein the processor is further configured to detect overdistension of lungs during pediatric ventilation based on the estimate of compliance and the feedback unit is further configured to provide information related to for appropriate lung ventilation volume for a pediatric patient.

31. The system of claim 1, wherein the processor is configured to detect a spontaneous breath based on information related to a negative pressure combined with inspiratory flow.

32. The system of claim 31, wherein the feedback unit is configured to provide a message indicating potential return of spontaneous circulation (ROSC) based on the detection of a spontaneous breath.

33. The system of claim 1, wherein the processor is further configured to:

generate an estimate of lung volume;

generate an estimate of a thoracic state impedance based on the estimate of lung volume;

provide the estimate of thoracic state impedance to an adaptive filter; and

filter ventilation-induced artifacts in the transthoracic impedance signal to generate an estimate of the impedance changes induced by cardiac output.

34. The system of claim 1, wherein the feedback unit is configured to provide a simultaneous display of flow rate and volume.

35. The system of claim 1, wherein the feedback comprises a graphical plot.

36. The system of claim 1, wherein the feedback comprises side-by-side numerics, the numerics comprising at least one numeric representative of the one or more ventilation parameters and a second numeric representative of the one or more chest compression parameters.

37. The system of claim 1, wherein the feedback comprises spirometery data for one or more of oxygen, carbon dioxide, overall gas volume and rate.

38. The system of claim 1, wherein the feedback comprises a value indicative of a measure of the squareness of a spirometry curve.

39. The system of claim 1, wherein the processor is further configured to:

receive information related to two or more of a patient'"'"'s height, girth, weight and gender; and

calculate an estimate thoracic volume based on the two or more of the patient'"'"'s height, girth, weight and gender.

40. The system of claim 39, wherein the processor is further configured to receive the information related to two or more of the patient'"'"'s height, girth, weight and gender from a tablet PC.

41. The system of claim 39, wherein the processor is further configured to receive the information related to two or more of the patient'"'"'s height, girth, weight and gender from an accelerometer.

42. The system of claim 39, wherein the processor is further configured to receive the information related to two or more of the patient'"'"'s height, girth, weight and gender from an automatic defibrillation and compression device configured to obtain a measure of patient circumference.

43. The system of claim 39, wherein the processor is further configured to calculate the estimate thoracic volume based on a measured ventilation tidal volume and an instantaneous lung volume.

44. The system of claim 1, wherein the patient ventilation unit comprises a handheld breathing tube.

45. The system of claim 1, wherein the patient ventilation unit comprises a mouthguard configured to fit between the patient'"'"'s lips and teeth and to provide a seal between the ventilation unit and the patient.

46. The system of claim 1, wherein the patient ventilation unit comprises a mask that seals to and fits over a lower portion of the patient'"'"'s face.

47. The system of claim 1, wherein the at least one first sensor comprises a differential pressure sensor.

55. The system of claim 1, wherein the chest compression feedback further comprises information about an effectiveness of chest compressions based on both the one or more ventilation quality parameters and the one or more chest compression parameters.

57. The system of claim 1, wherein at least one first sensor comprises an airflow sensor positioned in the airflow path and the at least one second sensor comprises a pressure sensor positioned in the airflow path.

48. A system for providing feedback on delivery of cardiopulmonary resuscitation (CPR), the system comprising:

a manual patient ventilation unit defining an airflow path, the unit arranged so that when the unit is applied to a patient, the airflow path is in fluid communication with the patient'"'"'s airway, the patient ventilation unit comprising;

a ventilation bag configured to enable manual ventilation of the patient by a rescuer;

at least one first sensor in the airflow path positioned to sense the presence of ventilation airflow and measure a gas flow rate in the airflow path; and

at least one second sensor in the airflow path positioned to sense gas pressure in the airflow path;

at least one chest compression sensor configured to detect and measure compression information based on chest compressions applied to the patient; and

a feedback unit separate from the manual patient ventilation unit comprising a processor arranged to;

wirelessly receive data generated by the at least one first sensor and the at least one second;

determine an instantaneous lung compliance measurement based at least in part on a gas flow volume calculated based on the sensed gas flow rate and gas pressures;

receive compression data generated by the at least one chest compression sensor;

determine one or more chest compression parameters based at least in part on the measured compression information; and

provide both ventilation feedback and chest compression feedback to a rescuer by the feedback unit, the ventilation feedback comprising the instantaneous lung compliance measurement and instructions for performing ventilations based upon a comparison of the instantaneous lung compliance measurement with a ventilation protocol comprising a range of predetermined acceptable instantaneous lung compliance values for administering ventilations to the patient and the chest compression feedback comprising the one or more chest compression parameters and instructions for performing chest compressions based upon a comparison of the chest compression parameters with a chest compression protocol comprising ranges of predetermined acceptable values for administering chest compressions to the patient.

49. The system of claim 48, wherein the processor is further configured to detect at least one of the following conditions based, at least in part, on the instantaneous lung compliance measurements:

barotrauma, hemothorax, pneumothorax, intubation in the mainstem, flail chest, or pediatric lung distension.

50. The system of claim 48, wherein the processor is further configured to detect overdistension of lungs during pediatric ventilation based on the estimate of instantaneous lung compliance and the feedback unit is further configured to provide information related to for appropriate lung ventilation volume for a pediatric patient.

51. The system of claim 48, wherein the processor is further configured to determine a patient state based on the instantaneous lung compliance measurement.

52. The system of claim 51, wherein the patient state comprises a state selected from the group consisting of barotraumas, hemothorax, pneumothorax, intubation in mainstem, flail chest, and pediatric lung overdistension.

53. The system of claim 48, wherein the feedback comprises spirometery data for one or more of oxygen, carbon dioxide, overall gas volume and rate.

54. The system of claim 48, wherein the feedback comprises a value indicative of a measure of the squareness of a spirometry curve.

56. The system of claim 48, wherein the chest compression feedback further comprises information about an effectiveness of the chest compressions based on the instantaneous lung compliance measurement and the one or more chest compression parameters.

58. The system of claim 48, wherein at least one first sensor comprises an airflow sensor positioned in the airflow path and the at least one second sensor comprises a pressure sensor positioned in the airflow path.