Methods and Devices for Central Photoplethysmographic Monitoring Methods

• US 20100192952A1
• Filed: 08/15/2006
• Published: 08/05/2010
• Est. Priority Date: 08/15/2006
• Status: Active Grant

• Current Assignee: Beta Biomed Services, Inc., Convergent Engineering, Inc., University of Florida Research Foundation, Incorporated (State University System of Florida)
• Original Assignee: University of Florida Research Foundation, Incorporated (State University System of Florida)
• Inventors: Melker, Richard J., Euliano, Neil R.
• Granted Patent: US 8,641,635 B2
• Time in Patent Office: Days
• US Class Current: 128/204.23
• CPC Class Codes: A61B 5/02 Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/6803 Head-worn items, e.g. helmets, masks, headphones or goggles
• CPC Class Codes: A61B 5/6815 Ear
• CPC Class Codes: A61B 5/6817 Ear canal
• CPC Class Codes: A61B 5/6819 Nose
• CPC Class Codes: A61B 5/6838 Clamps or clips
• CPC Class Codes: A61M 16/0051 with alarm devices
• CPC Class Codes: A61M 16/06 Respiratory or anaesthetic masks
• CPC Class Codes: A61M 16/0627 with sealing means on a part of the body other than the face, e.g. helmets, hoods or domes
• CPC Class Codes: A61M 16/0683 Holding devices therefor
• CPC Class Codes: A61M 2230/205 partial oxygen pressure (P-O2)
• CPC Class Codes: A61M 2230/432 partial CO2 pressure (P-CO2)

Abstract

Disclosed herein are methods and devices for delivering gas to a subject and obtaining plethysmograph readings from a subject. Specifically disclosed herein are masks and helmets which comprise one or more pulse oximeter probes associated therewith. The masks and helmets may be used in particular contexts, including, but not limited to, emergency responder personnel, pilots or subjects of medical attention.

Claims

1. A method of monitoring blood flow status to the head of an individual, said method comprising:

securing a pulse oximeter probe to a central source site of said individual wherein said probe is configured to generate signals indicative of blood flow at said central source site;

monitoring blood flow at said central source site; and

effecting a predetermined reaction responsive to said blood flow falling below a predefined value.

2. The method of claim 1 wherein said reaction comprises generating an alarm.

3. The method of claim 2 wherein said alarm is a visual, tactile or audible warning.

4. The method of claim 1 wherein said reaction comprises directing the flight control systems of said aircraft to undertake a corrective flight maneuver.

5. The method of claim 1 wherein said probe generates plethysmography signals.

6. The method of claim 5 wherein said monitoring blood flow comprises establishing a baseline value of plethysmography signals and comparing subsequently obtained plethysmography signals to said baseline value.

7. The method of claim 6, wherein said plethysmography signals comprise an AC component and a DC component, and wherein said AC component is isolated from the said plethysmography signals by identifying the peaks and troughs of said plethysmography signals;

identifying the midpoints or minimum values between said peaks and troughs, wherein the interpolated line connecting said midpoints or minimum values represents said DC component;

extracting said DC component from said plethysmography signals; and

obtaining said AC component.

8. A mask for delivering gas to a subject, said mask comprising

a compartment configured to cover the nose and mouth of said subject and an airhose attached to said compartment,

a pulse oximeter probe configured to secure to a central source site of said subject, said pulse oximeter probe connected to a wire for carrying signals produced by said pulse oximeter probe, wherein said wire is fixed to said mask.

9. The mask of claim 8, wherein said pulse oximeter probe is designed for use on said subject'"'"'s nasal alar comprising:

an elongated base configured for positioning along said subject'"'"'s nasal ridge, said elongated base comprising a proximal end and a distal end;

a bridge attached to or integral with said proximal end of said elongated base, said bridge having a right end portion and a left end portion;

a right flap extending from said right end portion of said bridge;

a left flap extending from said left end portion of said bridge;

at least one LED disposed in either said right flap or said left flap, or both; and

at least one wing fold extending down from either said right flap or said left flap, or both, said at least one wing fold comprising at least one photodetector disposed thereon and designed for insertion into said user'"'"'s right or left nostril such that said at least one photodetector is aligned across from said at least one LED.

10. The pulse oximeter probe of claim 9 comprising a first wing fold extending down from either said right flap or said left flap, said first wing fold comprising at least one photodetector disposed thereon and designed for insertion into said subject'"'"'s right or left nostril;

and a second wing fold extending down from either said right flap or said left flap, whichever said first flap is not extending down from, and designed for insertion into said user'"'"'s right or left nostril, wherein said first wing fold and said second wing fold are sufficiently rigid so as to hold their shape upon insertion into said user'"'"'s nostrils.

11. The pulse oximeter probe of claim 16 comprising a connector attached to or integrated at the proximal end of the elongated base, said connector configured for attachment and electrical communication with a corresponding receptacle.

12. The mask of claim 8, where said mask further comprises a strap for holding said mask to said subject'"'"'s face and a reflectance probe associated with said strap, said reflectance probe located along said strap so as to facilitate obtaining readings from said subject'"'"'s pre-auricular region or post-auricular region.

13. The mask of claim 12, wherein said probe comprises

a probe base structure attached to or integrated with said strap;

at least one LED disposed on said probe base structure; and

at least one photodetector disposed on said probe base structure and spaced proximally up from said at least one LED disposed on said probe base structure.

14. The reflectance probe of claim 13 further comprising a connector attached to or integrated with the proximal end of said wiring harness.

15. The reflectance probe of claim 12, wherein said at least one LED is positioned distal to said at least one photodetector at a spacing in the range of about 5 mm to about 30 mm.

16. The reflectance probe of claim 12, wherein said at least one LED is positioned distal to said at least one photodetector at a spacing in the range of about 8 mm to about 20 mm.

17. The reflectance probe of claim 12, wherein said at least one LED is positioned distal to said photodetector at a spacing in the range of about 10 mm to about 12 mm.

18. A mask for delivering gas to a subject, said mask comprising

a compartment configured to cover the nose and/or mouth of said subject and an airhose attached to said compartment, and

a pulse oximeter probe configured to secure to a central source site of said subject and monitor signals indicative of blood flow from said subject, said pulse oximeter probe associated with said mask.

19. The mask of claim 18, wherein said probe is communicatingly connected to a wireless transmitter.

20. The mask of claim 18, wherein said probe comprises a battery.

21. A system for monitoring signals indicative of blood flow at least one central source site of at least one subject, said system comprising

a mask for delivering gas to said subject;

at least one pulse oximeter probe configured to secure to a central source site of said subject and monitor signals indicative of blood flow from said subject, said pulse oximeter probe associated with said mask; and

a remote monitoring computer communicating connected with said at least one pulse oximeter probe, said remote monitoring computer configured to process signals from said at least one pulse oximeter probe.

22. The system of claim 21, wherein said at least one subject is an emergency responder and said at least one pulse oximeter probe comprises a wireless transmitter.

23. The system of claim 21, wherein said at least one subject is a patient in a medical facility.

24. The system of claim 21, wherein said remote monitoring computer is configured to determine plethysmography signals and/or oxygen saturation.

25. The system of claim 21, wherein said mask further comprises a CO2 sensor associated therewith, said capnography sensor being communicatingly connected to said remote monitoring computer.

26. The system of claim 21, wherein said mask further comprises a sampling apparatus to obtain exhaled gases for determination of carbon dioxide content associated with said mask and communicatingly connected to a capnography analyzer.

27. The system of claim 26, wherein said remote monitoring computer is communicatingly connected to said capnography analyzer and configured to process signals from said capnography analyzer.

28. A mask for delivering gas to a subject, said mask comprising

a nasal delivery portion;

at least one projection associated with said nasal delivery portion configured for insertion to at least nasal passage;

an airhose associated with said nasal delivery portion; and

a pulse oximeter probe configured to secure to a central source site of said subject, said pulse oximeter probe associated with said mask.

29. The mask of claim 28, further comprising a strap for holding said mask to said subject'"'"'s face and a reflectance probe associated with said strap, said reflectance probe located along said strap so as to facilitate obtaining readings from said subject'"'"'s pre-auricular region or post-auricular region.

30. The mask of claim 28, wherein said mask further comprises a wire connected to said probe, a battery connected to said wire and a wireless transmitter communicatingly connected to said probe.

31. A protective helmet comprising

a head covering portion defining a cavity into which an apex region of a user'"'"'s head is superimposed;

and

a pulse oximeter probe configured to secure to a central source site of said subject, said pulse oximeter probe associated with said helmet.

32. The protective helmet of claim 31, further comprising a tail portion extending from said head covering portion.

33. The protective helmet of claim 31, further comprising a strap and/or padding portion associated with said head covering portion, wherein said pulse oximeter probe is associated with said strap or padding portion.

34. The protective helmet of claim 31, wherein said head covering portion is made of a rigid material.

35. A helmet and mask system for use by an emergency responder, said helmet and mask system comprising

a head covering portion defining a cavity into which an apex region of a user'"'"'s head is superimposed;

a mask for delivering gas to a subject, said mask comprising a compartment configured to cover the nose and mouth of said subject and an airhose attached to said compartment; and

a pulse oximeter probe configured to secure to a central source site of said subject, said pulse oximeter probe associated with said helmet or mask.