Respiratory ventilation apparatus

• US 5,150,291 A
• Filed: 10/01/1990
• Issued: 09/22/1992
• Est. Priority Date: 03/31/1986
• Status: Expired due to Term

• Current Assignee: Puritan Bennett Corp. (Medtronic Plc)
• Original Assignee: Puritan Bennett Corp. (Medtronic Plc)
• Inventors: Prince, Robert I., Cummings, Charles C.
• Primary Examiner(s): Hayes, Gail O.
• Application Number:
  US07/593,324
• Time in Patent Office: 722 Days
• Field of Search: 324/413.02, 324/413.03, 137/908, 128/204.23, 128/204.24, 128/205.24, 128/205.24, 128/205.19
• US Class Current: 128/204.23
• CPC Class Codes: A61M 16/00 Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes stimulating the respiratory movement by mechanical, pneumatic or electrical means, iron lungs combined with gas breathing means A61H31/00
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 2230/005 Parameter used as control input for the apparatus
• CPC Class Codes: A61M 2230/04 Heartbeat characteristics, e.g. ECG, blood pressure modulation

Abstract

A gating system is provided for controlling a ventilator means, which, in turn, generates a positive pressure breath. The systems including a sensing means for sensing sequential heart beats of a patient, together with a computing means, which is connected to the sensing means, for computing a period between the sequential heart beats. In addition to the above, a valve means is connected electrically to the computing means and pneumatically to the ventilator means for controlling the ventilator means, with the valve means being positioned to cease positive pressure breaths in response to the computer period.

Claims

1. In a respiratory ventilation apparatus having a ventilator and a primary means for producing a pressure or volume supported breath cycle alternatingly providing a patient breathing pathway with a relatively high positive ventilation pressure and a relatively low positive ventilation pressure, the improvement comprising:

means for detecting heart beats in a plurality of cardiac cycles of said patient;

secondary means for producing said relatively low positive ventilation pressure in said patient breathing pathway commencing at a variable moment following a detected heart beat for a variable time interval during selected cardiac cycles; and

means for determining said variable moment including means for determining a period of time between selected sequential heart beats of said patient, and means for multiplying a preselected multiplier value by said period of time between said selected sequential heart beats, said preselected multiplier value approximately corresponding to a computed fraction of said period of time between heart beats.

2. The apparatus of claim 1, wherein said secondary means for producing said relatively low positive pressure comprises control means for generating a control signal for a predetermined period of time commencing at said variable moment during selected cardiac cycles of said patient, a control valve means connected to said patient breathing pathway having an open position in which said control valve means induces said relatively low pressure in said breathing pathway, and means operatively connected to said control means responsive to said control signal for opening said control valve means.

3. The apparatus of claim 2, wherein said control means comprises microprocessor means.

4. The apparatus of claim 3, further including means for storing said preselected multiplier value.

5. The apparatus of claim 2, wherein said means for opening said control valve means comprises a pneumatic control valve.

6. The apparatus of claim 2, wherein said means for opening said control valve means comprises an electronic valve control.

7. The apparatus of claim 5, wherein said pnenumatical control valve includes an inlet connected to a source of vacuum, an outlet in communication with said control valve means, switch means electrically connected to said control means and operative to communicate vacuum from said vacuum source to thereby open said control valve means in response to said control signal.

8. The apparatus of claim 6, wherein said electronic control valve includes a connection to said control means operative to communicate an electrical signal from said control means to said electronic valve in response to said control signal.

9. The apparatus of claim 1, wherein said means for detecting heat beats comprises means for generating an electrical heart bet signal in response to said heart beat.

10. The apparatus of claim 9, further including means for amplifying said electrical heart beat signal.

11. The apparatus of claim 9, wherein said means for generating an electrical heart beat signal comprises an electrocardiograph.

12. The apparatus of claim 9, wherein said means for generating an electrical heart beat signal comprises means for generating a light signal in response to said heart beat, and photodetector means for detecting said light signal operative to generate said electrical heart beat signal responsive to said light signal.

13. A respiratory ventilation apparatus, comprising:

a ventilator having means for producing a pressure or volume supported breath cycle alternatingly providing a patient breathing pathway with a relatively high positive ventilation pressure and a relatively low positive ventilation pressure;

means for detecting heart beats of said patient;

control means for generating a control signal for a predetermined period of time commencing at a variable moment following selected patient heart beats, said control means including means for determining said variable moment including means for determining a period of time between sequential heart beats of said patient, and means for multiplying a computed multiplier value by said period of time between sequential heart beats to thereby generated a value representing said variable moment;

control value means connected to said patient breathing pathway having an open position in which said control valve induces said relatively low pressure in said breathing pathway; and

means for opening said control valve means connected to said control means and responsive to said control signal.

14. The apparatus of claim 13, wherein said control means comprises microprocessor means.

15. The apparatus of claim 14, further including means for operator entry and storage of said preselected multiplier value.

16. In a respiratory ventilation apparatus having a ventilator and a primary means for producing a pressure or volume supported breath cycle alternatingly providing a patient breathing pathway with a relatively high positive ventilation pressure and a relatively low positive ventilation pressure, the improvement comprising:

means for detecting heart beats in a plurality of cardiac cycles of said patient, including means for generating an electrical heart beat signal in response to said heart beat, and amplifying means for squaring said electrical heart beat signal;

secondary means for producing said relatively low positive ventilation pressure in said patient breathing pathway commencing at a variable moment following a detected heart beat for a variable time interval during selected cardiac cycles; and

means for determining said variable moment.

17. The apparatus of claim 16, wherein said secondary means for producing said relatively low positive pressure comprises control means for generating a control signal for a predetermined period of time commencing at said variable moment during selected cardiac cycles of said patient, a control valve means connected to said patient breathing pathway having an open position in which said control valve means induces said relatively low pressure in said breathing pathway, and means operatively connected to said control means responsive to said control signal for opening said control valve means.

18. The apparatus of claim 17, wherein said means for opening said control valve means comprises a pneumatic control valve.

19. The apparatus of claim 18, wherein said pneumatic control valve includes an inlet connected to a source of vacuum, an outlet in communication with said control valve means, switch means electrically connected to said control means and operative to communicate vacuum from said vacuum source to thereby open said control valve means in response to said control signal.

20. The apparatus of claim 17, wherein said means for opening said control valve means comprises an electronic valve control.

21. The apparatus of claim 20, wherein said electronic control valve includes a connection to said control means operative to communicate an electrical signal from said control means to said electronic valve in response to said control signal.

22. The apparatus of claim 16, wherein said means for determining said variable moment comprises means for determining a period of time between selected sequential heart beats of said patient, and means for multiplying a preselected multiplier value by said period of time between said selected sequential heart betas, said preselected multiplier value approximately corresponding to a computed fraction of said period of time between heart beats.

23. The apparatus of claim 17, wherein said control means comprises microprocessor means.

24. The apparatus of claim 22, further including means for storing said preselected multiplier value.

25. The apparatus of claim 16, wherein said means for generating an electrical heart beat signal comprises an electrocardiograph.

26. The apparatus of claim 16, wherein said means for generating an electrical heart beat signal comprises means for generating a light signal in response to said heart beat, and photodetector means for detecting said light signal operative to generate said electrical heart beat signal responsive to said light signal.