Methods And Systems For Respiratory Monitoring With Photoplethysmography

Abstract

The present invention relates to optimized gas supply utilizing photoplethysmography. Flow rate, pressure or amount of gas is adjusted as a function of blood oxygen saturation data, photoplethysmography signals, or both, obtained from the pulse oximeter probe.

1 . A method of monitoring respiration in an individual, comprising isolating a DC component of a plethysmograph; and monitoring with a computer changes in an envelope of the isolated DC component of the plethysmograph to monitor respiration. 
     
     
         2 . The method of  claim 1 , further comprising quantifying the changes in the envelope of the isolated DC component to determine respiratory rate. 
     
     
         3 . The method of  claim 1 , wherein the plethysmograph is obtained from a plethysmography probe secured at a central source site. 
     
     
         4 . The method of  claim 3 , wherein the central source site is the nasal alar. 
     
     
         5 . The method of  claim 1 , wherein the plethysmograph is obtained from a spontaneously breathing individual. 
     
     
         6 . The method of  claim 1 , wherein changes in the envelope of the isolated DC component are used to determine the optimal level of positive end expiratory pressure (PEEP). 
     
     
         7 . The method of  claim 6 , wherein in the method further comprises adjusting the level of PEEP in response to the changes in the envelope of the plethysmograph. 
     
     
         8 . The method of  claim 1 , further comprising monitoring respiration with a separate monitoring sensor. 
     
     
         9 . The method of  claim 8 , wherein the separate monitoring sensor detects nasal air pressure, nasal air flow, or both. 
     
     
         10 . The method of  claim 8 , wherein the separate monitoring sensor comprises a capnography sensor. 
     
     
         11 . A system for monitoring respiration in an individual comprising: a computer configured to isolate a DC component from a plethysmograph, and to evaluate changes in an envelope of the isolated DC component to determine a breathing cycle of the individual. 
     
     
         12 . The system of  claim 11 , wherein the computer is further configured to determine respiration rate from the changes in the envelope of the isolated DC component. 
     
     
         13 . The system of  claim 11 , further comprising a pulse oximetry probe configured to secure to the nose of the individual. 
     
     
         14 . The system of  claim 13 , wherein the pulse oximetry probe is configured to secure to the nasal alar of the individual. 
     
     
         15 . The system of  claim 11 , wherein the system is further configured to increase or decrease a supply of oxygen to the individual in response to the changes in the envelope of the isolated DC component.