Systems, methods, and/or apparatuses for non-invasive monitoring of respiratory parameters in sleep disordered breathing
In certain example embodiments, an air delivery system includes a controllable flow generator operable to generate a supply of pressurized breathable gas to be provided to a patient for treatment and a pulse oximeter. In certain example embodiments, the pulse oximeter is configured to determine, for example, a measure of patient effort during a treatment period and provide a patient effort signal for input to control operation of the flow generator. Oximeter plethysmogram data may be used, for example, to determine estimated breath phase; sleep structure information; autonomic improvement in response to therapy; information relating to relative breathing effort, breathing frequency, and/or breathing phase; vasoconstrictive response, etc. Such data may be useful in diagnostic systems.
1. An air delivery system for clinical management and/or prediction of a patient's respiratory exacerbations, comprising:
a controllable flow generator operable to generate a supply of pressurized breathable gas to be provided to the patient for treatment;
a pulse oximeter configured to generate a signal indicative of the patient's relative breathing effort, breathing frequency, and/or breathing phase; and
a controller configured to:
determine the patient's relative breathing effort and breathing phase based on the signal generated by the pulse oximeter;
compare the determined respiratory effort to the determined breathing phase;
determine an amount of gas leaking from the supply of pressurized breathable gas provided to the patient; and
discriminate between a central apnea and a mixed apnea.
2. The air delivery system of claim 1 , wherein the patient's breathing phase includes inspiratory and/or expiratory timing.
3. The air delivery system of claim 1 , wherein the controller is configured to derive a representation of the patient's respiratory efficiency from inherent arterial oxygenation information provided by the pulse oximeter and the patient's relative breathing effort.
4. The air delivery system of claim 1 , wherein the discrimination between a central apnea and a mixed apnea is based on whether breathing effort precedes oxygen desaturation.
5. The air delivery system of claim 1 , wherein the discrimination between a central apnea and a mixed apnea is based on a pattern recognition and/or classifier techniques.
6. The air delivery system of claim 1 , wherein the pulse oximeter is a finger pulse oximeter.
7. The air delivery system of claim 1 , wherein the pulse oximeter is configured to be located at the patient's ear.
8. The air delivery system of claim 1 ,
wherein the air delivery system includes a provision for assessment of a patient's endothelial dysfunction,
wherein the pulse oximeter is further configured to measure the patient's vasoconstrictive response to the treatment, and
wherein the controller is further configured to trend the patient's vasoconstrictive response over a given time period to indicate a change in the patient's endothelial function.
9. The air delivery system of claim 8 , wherein the pulse oximeter is configured to measure spontaneous respiratory-related arousals and/or periodic respiratory-related arousals.
10. The air delivery system of claim 9 , wherein the spontaneous respiratory-related arousals and/or periodic respiratory-related arousals include changes in the patient's vascular compliance.
11. The air delivery system of claim 8 , wherein the controller is configured to restore a pressure of the breathable gas to a previous level when venous congestion worsens.
12. The air delivery system of claim 8 , wherein the time period is one of days, weeks, or months.
13. The air delivery system of claim 1 , wherein the controller is configured to determine the patient's breathing frequency based on the signal generated by the pulse oximeter.