NON-INVASIVE METHOD AND APPARATUS FOR DETERMINING LUNG TISSUE THERMAL PROPERTIES AND FOR EXTRA VASCULAR LUNG WATER MEASUREMENT

• US 20160213330A1
• Filed: 01/22/2015
• Published: 07/28/2016
• Est. Priority Date: 01/22/2015
• Status: Active Grant

• Current Assignee: Alexander Gelfand, Konstantin Goulitski
• Original Assignee: Alexander Gelfand, Konstantin Goulitski
• Inventors: Gelfand, Alexander, Goulitski, Konstantin
• Granted Patent: US 9,907,487 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/08 Detecting, measuring or recording devices for evaluating the respiratory organs A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/4878 Evaluating oedema

Abstract

The subject matter discloses a noninvasive method and device for detection, measurement and monitoring of Pulmonary Interstitial fluid—Extravascular Lung Water—volumes in inpatient settings: Intensive Care Units, Emergency Rooms, Internal Hospital Departments, and daily monitoring of chronic patient in outpatient settings: outpatient departments, rehab centers and Home monitoring. The disclosed method is based on the analysis of lung tissue thermodynamic properties, and their deviation from normal value. The device measures the rate of temperature change of a lung tissue by measuring the exhaled gas temperature changing rate during cooling/heating of lung tissue. The cooling/heating of lung tissue may be achieved by prompt changing one of the inhaled gas parameters temperature, and/or humidity, and/or rate of breathing, and/or tidal volume, and/or type of gas and etc. The change is performed at the beginning of measurement, and is kept during entire measurement time.

Claims

1. A non-invasive method for determining lung tissue thermal properties and for measuring extra vascular lung water. The method comprising:

measuring first temperatures or first flow of gas inhaled by a patient;

wherein properties of said inhales gas being changed while said measuring;

measuring second temperature or second flow of gas exhaled by said patient;

calculating rate of change of said second temperature or said second flow of said exhaled gas;

said rate of change being relative to change of said first temperature or said first flow; and

determining extravascular lung water volume in accordance with said calculated rate of change.

2. The method of claim 1 further comprises changing properties of said inhaled gas.

3. The method of claim 1, further comprising calculating the amount of said extra vascular lung water in accordance with a correlation function.

4. The method of claim 1, wherein said properties being one member of a group consisting of temperature, humidity, rate of breathing tidal volume and type of gas.

5. The method of claim 1, wherein said measuring said first temperature or said first flow of gas or said second temperature or said second flow of gas being for up to ten breathing cycles of said patient.

6. A non-invasive apparatus for determining lung tissue thermal properties and for measuring extra vascular lung water volume, the apparatus comprises:

a sensor [2] adapted for measuring first temperatures of gas inhaled by a patient or a sensor (3) adapted for measuring first flow of gas inhaled by said patient;

wherein properties of said inhales gas being changed while said measuring; and

a processing unit [7] being configured for calculating rate of change of second temperature or said second gas flow;

wherein said rate of change being relative to change of said first temperature or said first flow;

wherein said processing unit [7] being farther configured for determining extravascular lung water in accordance with said calculated rate.

7. The apparatus of claim 6 farther comprising a humidifier [22] being adapted for controlling said properties of said inhaled gas.

8. The apparatus of claim 6, wherein said patient being ventilated or non-ventilated.

9. The apparatus of claim 6, wherein said apparatus being configured for measuring up to ten breathing cycles of said patient.