Monitoring physiological parameters based on variations in a photoplethysmographic baseline signal
First Claim
1. A method for use in noninvasively monitoring a physiological parameter of a patient, comprising the steps of:
- obtaining a photoplethysmographic (“
pleth”
) signal that is modulated based on interaction of a transmitted optical signal with blood of said patient, wherein said pleth signal includes at least a first respiratory component and a second Mayer wave component associated with the patient'"'"'s autonomic nervous system;
processing said pleth signal relative to said first and second components to distinguish effects associated with said first respiratory component from effects associated with said second Mayer wave component; and
monitoring a respiration rate of said patient'"'"'s breathing using at least one said distinguished effect.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and apparatus are disclosed for using photoplethysmography to obtain physiological parameter information related to respiration or the autonomic nervous system. In one implementation, the process involves obtaining (602) a pleth, filtering (604) the pleth to remove unwanted components, identifying (606) a signal component of interest based on the filtered signal, monitoring (608) blood pressure changes, monitoring (610) heart rate, and performing (612) an analysis of the blood pressure signal to the heart rate signal to identify a phase relationship associated with the component of interest. Based on this phase relationship, the component of interest may be identified (614) as relating to the respiration or Mayer Wave. If it is related to the respiration wave (616), a respiratory parameter such as breathing rate may be determined (620). Otherwise, a Mayer Wave analysis (618) may be performed to obtain parameter information related to the autonomic nervous system.
-
Citations
39 Claims
-
1. A method for use in noninvasively monitoring a physiological parameter of a patient, comprising the steps of:
-
obtaining a photoplethysmographic (“
pleth”
) signal that is modulated based on interaction of a transmitted optical signal with blood of said patient, wherein said pleth signal includes at least a first respiratory component and a second Mayer wave component associated with the patient'"'"'s autonomic nervous system;
processing said pleth signal relative to said first and second components to distinguish effects associated with said first respiratory component from effects associated with said second Mayer wave component; and
monitoring a respiration rate of said patient'"'"'s breathing using at least one said distinguished effect. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method for use in monitoring a patient'"'"'s breathing comprising the steps of:
-
transmitting an optical signal relative to said patient such that said signal interacts with blood of said patient;
operating a detector system to detect said transmitted optical signal and provide a photoplethysmographic (“
pleth”
) signal reflective of said detected optical signal, where said pleth signal includes at least a first respiratory component and a second Mayer wave component associated with the patient'"'"'s autonomic nervous system;
first processing said pleth signal to isolate a pulsatile pleth signal and a baseline pleth signal;
second processing said baseline pleth signal to distinguish effects associated with the said first respiratory component from effects associated with said second Mayer wave component; and
using said distinguished effects to monitor said patient'"'"'s breathing. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20)
-
-
21. An apparatus for use in monitoring a patient'"'"'s breathing, comprising:
-
a port for receiving a photoplethysmographic (“
pleth”
) signal that is modulated based on interaction of a transmitted optical signal with blood of said patient, wherein said pleth signal includes at least a first component associated with the operation of the patient'"'"'s respiratory system and a second component associated with the patient'"'"'s autonomic nervous system; and
a processor operated for processing the pleth signal to distinguish an effect associated with one of said first and second components from an effect associated with the other of said components, wherein said processor is operative for distinguishing said effect by determining first information related to a first signal defined by variations in blood pressure over time, determining second information related to a second signal defined by variations in heart rate over time, and using said first information and said second information to obtain third information related to a waveform difference between said first signal and said second signal and for using said distinguished effect to monitor said physiological parameter. - View Dependent Claims (22, 23, 24, 25, 26, 27, 28, 29, 30)
-
-
31. A method for use in noninvasively monitoring a physiological parameter of a patient, comprising the steps of:
-
obtaining a photoplethysmographic (“
pleth”
) signal that is modulated based on interaction of a transmitted optical signal with blood of said patient, wherein said pleth signal includes at least a first component associated with the operation of the patient'"'"'s respiratory system and a second component associated with the patient'"'"'s autonomic nervous system;
processing said pleth signal relative to said first and second components;
distinguishing an effect associated with one of said first and second components from an effect associated with the other of said components, wherein said distinguishing comprises determining first information related to a first signal defined by variations in blood pressure over time, determining second information related to a second signal defined by variations in heart rate over time, and using said first information and said second information to obtain third information related to a waveform difference between said first signal and said second signal; and
using said distinguished effect to monitor said physiological parameter. - View Dependent Claims (32, 33, 34, 35, 36, 37, 38, 39)
-
Specification