RESPIRATORY FUNCTION MEASURING APPARATUS

• US 20100317932A1
• Filed: 12/15/2009
• Published: 12/16/2010
• Est. Priority Date: 12/22/2008
• Status: Abandoned Application

• Current Assignee: Nihon Kohden Corporation
• Original Assignee: Nihon Kohden Corporation
• Inventors: UKAWA, Teiji
• Application Number:
  US12/638,658
• Publication Number:
  US 20100317932A1
• Time in Patent Office: Days
• US Class Current: 600/301
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• 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 5/02108 from analysis of pulse wave characteristics
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/0535 Impedance plethysmography for measuring blood flow A61B5/0295
• CPC Class Codes: A61B 5/0809 by impedance pneumography
• CPC Class Codes: A61B 5/0836 Measuring rate of CO2 production
• CPC Class Codes: A61B 5/087 Measuring breath flow
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: G06F 2218/10 by analysing the shape of a waveform, e.g. extracting parameters relating to peaks

Abstract

A respiratory function measuring apparatus includes: a first sensor configured to detect an invasive blood pressure; a second sensor configured to measure frequency of at least one of a heart beat and a respiration; and a controller configured to extract a respiratory function signal from the invasive blood pressure detected by the first sensor, by using at least one of the frequency measured by the second sensor and a harmonic of the frequency.

Claims

1. A respiratory function measuring apparatus comprising:

a first sensor configured to detect an invasive blood pressure;

a second sensor configured to measure frequency of at least one of a heart beat and a respiration; and

a controller configured to extract a respiratory function signal from the invasive blood pressure detected by the first sensor, by using at least one of the frequency measured by the second sensor and a harmonic of the frequency.

2. The respiratory function measuring apparatus according to claim 1, wherein

the controller presumes the extracted respiratory function signal as an intrathoracic pressure.

3. The respiratory function measuring apparatus according to claim 1, wherein

when the second sensor measures the frequency of the heart beat, the controller selectively removes components corresponding to the frequency of the heart beat and a harmonic of the frequency from a signal corresponding to the invasive blood pressure.

4. The respiratory function measuring apparatus according to claim 1, wherein

when the second sensor measures the frequency of the heart beat, the controller extracts a component corresponding to a frequency which is lower than the frequency of the heart beat from a signal corresponding to the invasive blood pressure.

5. The respiratory function measuring apparatus according to claim 1, wherein

when the second sensor measures the frequency of the respiration, the controller extracts components corresponding to the frequency of the respiration and a harmonic of the frequency from a signal corresponding to the invasive blood pressure.

6. The respiratory function measuring apparatus according to claim 1, wherein

the frequency of the heart beat is measured from an electrocardiogram, a plethysmogram, or an arterial blood pressure.

7. The respiratory function measuring apparatus according to claim 1, wherein

the frequency of the respiration is measured from a capnometry, a respiratory flow, an airway pressure, a transthoracic electrical impedance, or a respiratory temperature.

8. The respiratory function measuring apparatus according to claim 1, wherein

the invasive blood pressure is a central venous pressure (CVP) or a peripheral venous pressure.

9. The respiratory function measuring apparatus according to claim 1, further comprising:

a respiration variation detector, wherein

when the second sensor measures the frequency of the respiration, the second sensor presumes an end-tidal, and

the respiration variation detector is configured to obtain a degree of a respiratory signal with respect to the end-tidal.

10. The respiratory function measuring apparatus according to claim 9, wherein

the end-tidal is obtained from a flat portion of the invasive blood pressure, a capnometry, a respiratory flow, an airway pressure, a transthoracic electrical impedance, or a respiratory temperature.

11. The respiratory function measuring apparatus according to claim 9, further comprising:

a respiration determiner configured to, based on a polarity of a degree of the respiratory signal, determine whether the respiration is spontaneous respiration or artificial respiration.

12. The respiratory function measuring apparatus according to claim 9, further comprising:

a secondary respiratory function calculator configured to, based on a level of the respiratory signal, obtain at least one of a PTP, an intrinsic PEEP, a work of breathing, and a P0.1.

13. The respiratory function measuring apparatus according to claim 9, wherein

the respiratory signal is displayed as a painted-out portion based on a timing of the end-tidal.

14. The respiratory function measuring apparatus according to claim 9, wherein

a mark indicative of a timing of the end-tidal is displayed with a waveform.

15. The respiratory function measuring apparatus according to claim 9, wherein

a waveform display is performed with plotting the respiratory signal as an abscissa, and a respiratory volume which is obtained by integrating a respiratory flow, as an ordinate.