SYSTEM AND METHOD FOR ASSESSING TREATMENT EFFECTS ON OBSTRUCTIVE SLEEP APNEA

• US 20150223699A1
• Filed: 08/03/2014
• Published: 08/13/2015
• Est. Priority Date: 02/11/2014
• Status: Active Grant

• Current Assignee: Seoul National University Bundang Hospital (Seoul National University)
• Original Assignee: Seoul National University Bundang Hospital (Seoul National University)
• Inventors: CHANG, Jae Seung, YOON, In-Young, HA, Kyooseob
• Granted Patent: US 10,149,621 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/4818 Sleep apnoea
• CPC Class Codes: A61B 5/4848 Monitoring or testing the effects of treatment, e.g. of medication
• CPC Class Codes: A61M 16/04 Tracheal tubes catheters in general A61M25/00
• CPC Class Codes: A61M 16/0488 Mouthpieces; Means for guiding, securing or introducing the tubes guiding or introducing with laryngoscopes A61B1/267; holding devices on the body A61M25/02
• CPC Class Codes: A61M 16/14 by mixing different fluids, one of them being in a liquid phase
• CPC Class Codes: A61M 2016/0033 electrical
• CPC Class Codes: A61M 2202/0208 Oxygen
• CPC Class Codes: A61M 2202/0468 non-physiological
• CPC Class Codes: A61M 2205/581 by audible feedback
• CPC Class Codes: A61M 2205/584 having a color code
• CPC Class Codes: A61M 2205/8206 battery-operated

Abstract

A system and method for assessing treatment effects on obstructive sleep apnea are provided. The apparatus includes a bio-signal measurement unit, a combined index calculation unit, and a treatment response assessment unit. The bio-signal measurement unit measures each of the electrocardiogram and respiratory rhythm of a patient. The combined index calculation unit calculates a combined cardiac and respiratory index by combining the heart rate variability and respiratory rhythm signals measured by the bio-signal measurement unit. The treatment response assessment unit assesses a response of the patient to the treatment of obstructive sleep apnea.

Claims

1. A system for assessing treatment effects on obstructive sleep apnea, the system comprising:

a bio-signal measurement unit configured to measure each of an electrocardiogram and respiratory rhythm of a patient;

a combined index calculation unit configured to calculate a combined cardiac and respiratory index by combining the heart rate variability and respiratory rhythm signals measured by the bio-signal measurement unit; and

a treatment response assessment unit configured to assess response of the patient to treatment of obstructive sleep apnea.

2. The system of claim 1, wherein the combined index calculation unit comprises:

a heart rate variability entropy calculation unit configured to calculate a non-linear sample entropy index that is used to assess time series regularity of heart rate variability;

a respiratory rhythm entropy calculation unit configured to calculate a non-linear sample entropy index that is used to assess time series regularity of respiratory rhythm; and

a cross-sample entropy calculation unit configured to calculate the combined cardiac and respiratory index by combining a heart rate variability entropy index with a respiratory rhythm entropy index.

3. The system of claim 2, wherein the heart rate variability sample entropy and the respiratory rhythm sample entropy are calculated using the following equation 4:

SampEn(m,r,N)=−

In(c_(m+1)(r)/c_m(r)) 

 

(4)

4. The system of claim 1, wherein the treatment response assessment unit is configured to:

assess the treatment effects on obstructive sleep apnea based on a change in the combined cardiac and respiratory index or a difference of the combined cardiac and respiratory index from that of a normal control; and

determine that the coordination between heart rate and respiratory rhythm is low if a value of the combined cardiac and respiratory index is higher than an upper limit of a normal range, and determine that the coordination between heart rate and respiratory rhythm is high if the value of the combined cardiac and respiratory index is lower than a lower limit of the normal range.

5. The system of claim 4, wherein the normal range of the combined cardiac and respiratory index is a range from 0.46 to 0.58.

6. The system of claim 4, further comprising a customized management unit connected with the treatment response assessment unit, and configured to establish a treatment method and a plan for the patient based on treatment effects on obstructive sleep apnea.

7. The system of claim 1, further comprising a treatment/assessment information unit connected with the treatment response assessment unit, and configured to store and manage information about the combined cardiac and respiratory index of a normal control and information about a history of treatment of obstructive sleep apnea of the patient.

8. The system of claim 1, wherein the bio-signal measurement unit is implemented in a portable form that can be carried by the patient, and is attached to or worn on a wrist and chest of the patient and measures the electrocardiogram and respiratory rhythm of the patient;

and further comprises a separate data communication unit, and transmits the measured electrocardiogram and respiratory rhythm to an external location.

9. A method of assessing treatment effects on obstructive sleep apnea, the method comprising the steps of:

(a) measuring each of an electrocardiogram and respiratory rhythm of a patient using a bio-signal measurement unit;

(b) calculating a combined cardiac and respiratory index by combining the heart rate variability and respiratory rhythm signals, measured at step (a), using a combined index calculation unit;

(c) comparing the calculated combined cardiac and respiratory index with that of a normal control group using a treatment response assessment unit; and

(d) assessing a level of post-treatment recovery on based on results of the comparison.

10. The method of claim 9, wherein step (b) comprises the steps of:

(b-1) calculating heart rate sample entropy (SampEn_RR) and respiratory rhythm sample entropy (SampEn_rep) using a heart rate entropy calculation unit and a respiratory rhythm entropy calculation unit, respectively; and

(b-2) calculating the combined cardiac and respiratory index (Cross-SampEn) by combining the heart rate sample entropy with the respiratory rhythm sample entropy using a cross-sample entropy calculation unit.

11. The method of claim 10, wherein the heart rate variability sample entropy index and the respiratory rhythm sample entropy index at step (b) are calculated using the following equation 4:

SampEn(m,r,N)=−

In(c_(m+1)(r)/c_m(r)) 

 

(4)

12. The method of claim 10, wherein a normal range of the combined cardiac and respiratory index (Cross-SampEn) at step (b-2) is a range from 0.46 to 0.58.

13. The method of claim 9, further comprising, after step (d), step (e) of establishing a treatment method and a plan for the patient based on treatment effects on obstructive sleep apnea using a customized management unit.

14. The method of claim 13, further comprising, after step (e), step (f) of storing information about the combined cardiac and respiratory index of a normal control and information about a history of treatment of obstructive sleep apnea of the patient using a treatment/assessment information unit.