Pulse transmit time measurement device and method

• US 10,085,653 B2
• Filed: 09/09/2015
• Issued: 10/02/2018
• Est. Priority Date: 09/09/2014
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Kahlert, Joachim, Aelen, Paul, Aarts, Ronaldus Maria
• Primary Examiner(s): Natnithithadha, Navin
• Application Number:
  US14/848,432
• Publication Number:
  US 20160066801A1
• Time in Patent Office: 1,119 Days
• Field of Search: 600481, 600483, 600485, 600500-503, 600509, 600513, 600538
• CPC Class Codes: A61B 5/0053 by applying pressure, e.g. compression, indentation, palpation, grasping, gauging
• 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 5/02125 of pulse wave propagation time
• CPC Class Codes: A61B 5/02133 by using induced vibration of the blood vessel
• CPC Class Codes: A61B 5/038 Measuring oral pressure
• CPC Class Codes: A61B 5/085 Measuring impedance of respiratory organs or lung elasticity
• CPC Class Codes: A61B 5/087 Measuring breath flow
• CPC Class Codes: A61B 5/1107 Measuring contraction of parts of the body, e.g. organ, muscle apparatus for measuring work or force in general G01L
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/352 Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
• CPC Class Codes: A61B 5/682 Mouth, e.g., oral cavity; tongue; Lips; Teeth
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 7/04 Electric stethoscopes microphones, acoustic transducers therefor H04R

Abstract

Proposed is a Pulse Transit Time, PTT, measurement concept wherein a forced oscillation technique, FOT, is used to determine a pulse arrival time at alveoli of the lungs of a patient.

Claims

1. A method comprising the steps of:

determining a pulse start time;

using a forced oscillation technique to determine a pulse arrival time at alveoli of lungs of a patient, the determination of the pulse arrival time based on determining a change in impedance at the alveoli, the change in impedance based on a blood pressure wave arriving at the alveoli;

determining a pulse transit time based on the pulse start time and the pulse arrival time; and

transmitting the pulse transit time to an output interface for monitoring of a cardiovascular function for the patient.

2. The method of claim 1, wherein the step of determining a pulse start time comprises:

using a phonocardiograph to determine a point in time when a heart pulmonary valve of the patient opens.

3. The method of claim 1, wherein the step of determining a pulse start time comprises:

using an electrocardiogram to determine a point in time when a right ventricle of a heart of the patient contracts.

4. The method of claim 1, wherein using a forced oscillation technique comprises:

applying pressure oscillations into airways of the patient at a higher frequency than a natural breathing frequency of the patient.

5. The method of claim 1, further comprising measuring blood pressure based on the pulse transit time.

17. The method of claim 1, wherein transmitting comprises transmitting the pulse transit time on a beat-by-beat basis.

6. A pulse transit time measurement device, comprising:

a pulse detection unit adapted to determine a pulse start time;

a forced oscillation technique unit adapted to perform a forced oscillation technique to determine a pulse arrival time at alveoli of the lungs of a patient, the determination of the pulse arrival time based on determining a change in impedance at the alveoli, the change in impedance based on a blood pressure wave arriving at the alveoli; and

a processing unit adapted to determine the pulse transit time based on the pulse start time and the pulse arrival time and transmit the pulse transit time to an output interface for monitoring of a cardiovascular function for the patient.

7. The pulse transit time measurement device of claim 6, wherein the pulse detection unit comprises:

a phonocardiograph apparatus adapted to determine a point in time when a heart pulmonary valve of the patient opens.

8. The pulse transit time measurement device of claim 6, wherein the pulse detection unit comprises:

an electrocardiogram apparatus adapted to determine a point in time when a right ventricle of a heart of the patient contracts.

9. The pulse transit time measurement device of claim 6, wherein the forced oscillation technique unit comprises an apparatus adapted to apply pressure oscillations into airways of the patient at a higher frequency than a natural breathing frequency of the patient.

18. The pulse transit time measurement device of claim 6, wherein the pulse transit time is transmitted to the output interface on a beat-by-beat basis.

10. A system, comprising:

a pulse detection unit adapted to determine a pulse start time;

a forced oscillation technique unit adapted to perform a forced oscillation technique to determine a pulse arrival time at alveoli of the lungs of a patient, the determination of the pulse arrival time based on determining a change in impedance at the alveoli, the change in impedance based on a blood pressure wave arriving at the alveoli; and

a processing unit adapted to determine the pulse transit time based on the pulse start time and the pulse arrival time and transmit the pulse transit time to an output interface for monitoring of a cardiovascular function for the patient.

11. The system of claim 10, wherein the pulse detection unit comprises:

a phonocardiograph apparatus adapted to determine a point in time when a heart pulmonary valve of the patient opens.

12. The system of claim 10, wherein the pulse detection unit comprises:

an electrocardiogram apparatus adapted to determine a point in time when a right ventricle of a heart of the patient contracts.

13. The system of claim 10, wherein the forced oscillation technique-unit comprises an apparatus adapted to apply pressure oscillations into airways of the patient at a higher frequency than a natural breathing frequency of the patient.

14. The system of claim 10, wherein the system comprises a blood pressure measurement device comprising the pulse detection unit, the forced oscillation technique unit, and the processing unit.

15. The system of claim 10, wherein the system comprises a cardiac monitoring system comprising the pulse detection unit, the forced oscillation technique unit, and the processing unit.

16. The system of claim 10, wherein the system comprises a spirometer comprising the pulse detection unit, the forced oscillation technique unit, and the processing unit.

19. The system of claim 10, wherein the pulse transit time is transmitted to the output interface on a beat-by-beat basis.