System and method for assessing treatment effects on obstructive sleep apnea

• US 10,149,621 B2
• Filed: 08/03/2014
• Issued: 12/11/2018
• 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: Yoon, In-Young, Ha, Kyooseob, Chang, Jae Seung
• Primary Examiner(s): Mallari, Patricia
• Assistant Examiner(s): PORTILLO, JAIRO H
• Application Number:
  US14/450,244
• Publication Number:
  US 20150223699A1
• Time in Patent Office: 1,591 Days
• Field of Search: None
• 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 method of assessing treatment effects on obstructive sleep apnea, the method comprising:

(a) measuring each of an electrocardiogram and respiratory rhythm of a patient using a bio-signal measurement unit comprised of an electrocardiogram measurement unit measuring the electrocardiogram and a respiratory rhythm measurement unit which is different from the electrocardiogram measurement unit and measures the respiratory rhythm;

(b) obtaining, with a combined index calculation unit comprised of a heart rate variability entropy calculation unit, a respiratory rhythm entropy calculation unit, and a cross-sample entropy calculation unit, a combined cardiac and respiratory index by combining heart rate variability and respiratory rhythm signals, measured at the step (a), the obtaining comprises;

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

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

(c) assessing, with a treatment response assessment unit, a response of the patient to treatment of obstructive sleep apnea by using the combined cardiac and respiratory index,

wherein an abnormality in central autonomic regulation is quantified and a response of a patient to continuous positive airway pressure (CPAP) is quantified based on the combined cardiac and respiratory index,

wherein the step (c) comprises;

assessing 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

determining 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 determining 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,

wherein the heart rate variability sample entropy and the respiratory rhythm sample entropy at the step (b) are calculated using density correlation functions C_i,m(r) C_i,(m+1)(r);

2. The method of claim 1, wherein the normal range of the combined cardiac and respiratory index is a range from 0.46 to 0.58.

3. The method of claim 1, further comprising, after the step (c), establishing a treatment method and a plan for the patient based on treatment effects on obstructive sleep apnea using a customized management unit.

4. The method of claim 3, further comprising, after the step (c), storing and managing information about the combined cardiac and respiratory index of the normal control and information about a history of treatment of obstructive sleep apnea of the patient using a treatment/assessment information unit.

5. The method 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.

6. The method of claim 5, wherein the bio-signal measurement unit and the separate data communication unit are included in a smartphone.

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

(a) measuring an electrocardiogram of a patient by using an electrocardiogram measurement unit worn on a wrist of the patient and measuring respiratory rhythm of the patient by using a respiratory rhythm measurement unit which is worn on a chest of the patient, wherein an electrocardiogram measurement unit and the respiratory rhythm measurement unit area each in a portable form;

(b) obtaining, with a combined index calculation unit comprised of a heart rate variability entropy calculation unit, a respiratory rhythm entropy calculation unit, and a cross-sample entropy calculation unit, a combined cardiac and respiratory index by combining heart rate variability and respiratory rhythm signals, measured at the step (a), the obtaining comprises;

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

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

(c) assessing, with a treatment response assessment unit, a response of the patient to treatment of obstructive sleep apnea by using the combined cardiac and respiratory index,

wherein an abnormality in central autonomic regulation is quantified and a response of a patient to continuous positive airway pressure (CPAP) is quantified based on the combined cardiac and respiratory index,

wherein the step (c) comprises;

assessing 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

determining 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 determining 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,

wherein the heart rate variability sample entropy and the respiratory rhythm sample entropy at the step (b) are calculated using density correlation functions C_i,m(r) and C_i,(m+1)(r);