Methods for measurement of hemodynamics

• US 20030093000A1
• Filed: 07/01/2002
• Published: 05/15/2003
• Est. Priority Date: 07/02/2001
• Status: Active Grant

• Current Assignee: Ryosuke Nishio
• Original Assignee: Kansai Technology Licensing Organization Co., Ltd., Medical Microtechnology, Inc.
• Inventors: Matsumori, Akira, Nishio, Ryosuke
• Granted Patent: US 6,695,788 B2
• Time in Patent Office: Days
• US Class Current: 600/486
• 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 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• CPC Class Codes: A61B 5/0535 Impedance plethysmography for measuring blood flow A61B5/0295
• CPC Class Codes: A61B 5/0538 invasively, e.g. using a catheter

Abstract

A method for measuring hemodynamics of an experimental animal enabling repeated measurements, the method comprising the following steps:

(i) ligating at least two parts of an artery, between which a part to be incised is located, of the experimental animal, the parts comprising at least one proximal ligated part and at least one distal ligated part, and then incising a part between the ligated parts;

(ii) inserting through the incised part a blood pressure-volume simultaneously measuring catheter provided with multiple conductance electrodes and at least one pressure sensor;

(iii) loosening the distal ligated part so as to allow an insertion of the catheter and not to cause bleeding in the opened part;

(iv) further inserting the catheter so as to introduce the multiple conductance electrodes and the pressure sensor(s) into the heart ventricle; and

(v) simultaneously measuring pressure and volume of the heart.

Claims

1. A method for measuring hemodynamics of an experimental animal enabling repeated measurements, the method comprising the following steps:

(i) ligating at least two parts of an artery, between which a part to be incised is located, of the experimental animal, the parts comprising at least one proximal ligated part and at least one distal ligated part, and then incising a part between the ligated parts;

(ii) inserting through the incised part a blood pressure-volume simultaneously measuring catheter provided with multiple conductance electrodes and at least one pressure sensor;

(iii) loosening the distal ligated part so as to allow an insertion of the catheter and not to cause bleeding in the opened part;

(iv) further inserting the catheter so as to introduce the multiple conductance electrodes and the pressure sensor(s) into the heart ventricle; and

(v) simultaneously measuring pressure and volume of the heart.

2. The method according to claim 1, further comprising the following steps:

(vi) pulling the catheter until a tip of the catheter is positioned between the proximal ligated part and the incised part;

(vii) ligating the proximal ligated part to such an extent as to prevent bleeding in the opened part after the catheter is completely pulled out;

(viii) pulling out the catheter and suturing the opened part; and

(ix) untying the proximal ligated part and the distal ligated part.

3. The method according to claim 1, wherein the artery of the experimental animal is cranial to the heart.

4. The method according to claim 3, wherein the artery cranial to the heart is a carotid artery.

5. The method according to claim 1, further comprising a step of investigating time-course of hemodynamics by repeatedly measuring hemodynamics in a single individual animal.

6. The method according to claim 1, wherein in the step (i), ligating three parts of the artery, among which a part to be incised is located, the three parts being two proximal ligated parts and a distal ligated part, and in the step (iii), loosening the two proximal ligated parts.

7. The method according to claim 1, wherein the experimental animal is a mouse.