Cardiac output and right ventricular ejection fraction system

• US 5,383,468 A
• Filed: 10/29/1991
• Issued: 01/24/1995
• Est. Priority Date: 10/31/1990
• Status: Expired due to Fees

• Current Assignee: Nihon Kohden Corporation
• Original Assignee: Nihon Kohden Corporation
• Inventors: Imai, Takasuke, Shioya, Shiniti, Sato, Yoji, Yamamori, Shinji, Nakayama, Tadashi, Ono, Kohei, Hosaka, Hidehiro
• Primary Examiner(s): Sykes, Angela D.
• Application Number:
  US07/783,930
• Time in Patent Office: 1,183 Days
• Field of Search: 128/691.4, 128/713, 128/736
• US Class Current: 600/526
• CPC Class Codes: A61B 5/028 by thermo-dilution

Abstract

A cardiac output and right ventricular ejection fraction computer comprises a catheter, having an indicator injection port which is located at the right ventricular, inserted into an intravascular of a patient and retained therein; thermal detector device, mounted on a distal portion of the catheter, for detecting the temperature of blood ejected from the right ventricle; signal processor device for calculating the right ventricular ejection fraction from a thermodilution curve obtained by detecting variation of the blood temperature measured by the thermal detector device when a indicator is injected into the right ventricular through the catheter; data input device for inputting data to the signal processor device.

Claims

1. A cardiac output and right ventricular ejection fraction system comprising:

a catheter, having an indicator injection portion which is located at the right ventricle, adapted to be inserted intravascularly into a patient and retained therein;

thermal detector means, mounted on a distal portion of said catheter, for detecting the temperature of blood ejected from said right ventricle;

signal processor means for calculating said right ventricular ejection fraction from a thermodilution curve obtained by detecting variation of said blood temperature measured by said thermal detector means when an indicator is inserted into the right ventricle through said catheter; and

data input means for inputting data to said signal processor means;

wherein said data includes an insert length of said catheter.

2. A cardiac output and right ventricular ejection fraction system comprising:

a catheter, having an indicator insection port which is located at the right ventricle, adapted to be inserted intravascularly into a patient and retained therein;

thermal detector means, mounted on a distal portion of said catheter, for detecting the temperature of blood ejected from said right ventricle,

signal processor means for calculating said right ventricular ejection fraction from a thermodilution curve obtained by detecting variation of said blood temperature measured by said thermal detector means when an indicator is inserted into the right ventricle through said catheter;

data input means for inputting data to said signal processor means;

wherein said data includes an insert length of said catheter; and

wherein said signal processor means calculates said right ventricular ejection fraction by correcting a measurement error attributable to said insert length of said catheter.

3. A cardiac output and right ventricular ejection fraction system as claimed in claim 2, wherein said indicator injection port injects an indicator which is substantially 0°

C. cold water including one of physiological saline and 5% dextran.