Capnometer

• US 5,738,106 A
• Filed: 02/23/1996
• Issued: 04/14/1998
• Est. Priority Date: 02/23/1995
• Status: Expired due to Term

• Current Assignee: Nihon Kohden Corporation
• Original Assignee: Nihon Kohden Corporation
• Inventors: Ito, Masami, Inoue, Masayuki, Sugiura, Masaki, Yamamori, Shinji, Ono, Kohei, Kasuya, Hiromitsu
• Primary Examiner(s): Bahr, Jennifer
• Assistant Examiner(s): YARNELL, BRYAN KEITH
• Application Number:
  US08/605,928
• Time in Patent Office: 781 Days
• Field of Search: 128/716, 128/718, 128/719, 128/204.22, 128/204.23, 128/633, 128/664, 73/23.3
• US Class Current: 600/532
• CPC Class Codes: A61B 5/0836 Measuring rate of CO2 production
• CPC Class Codes: A61B 5/7415 Sound rendering of measured values, e.g. by pitch or volume variation A61B5/741 takes precedence

Abstract

The capnometer of the invention is an equipment which detects a signal which time-varies in accordance with a carbon dioxide concentration from a respiration gas, thereby calculating the carbon dioxide concentration. The capnometer has: carbon dioxide concentration calculating device for detecting the maximum value for each expiration from a concentration signal corresponding to the calculated carbon dioxide concentration, for comparing the maximum value with concentration signals respectively corresponding to a plurality of predetermined concentration ranges, and for outputting one of different control signals for the concentration ranges; and reporting device for outputting a sound corresponding to the carbon dioxide concentration, in accordance with the control signal.

Claims

1. A capnometer comprising:

carbon dioxide concentration calculating means for detecting a concentration signal corresponding to a carbon dioxide concentration for each expiration, for comparing said concentration signal with concentrations respectively corresponding to a plurality of predetermined concentration ranges, and for outputting a control signal, from among different control signals respectively corresponding to said predetermined concentration ranges, corresponding to a detected carbon dioxide concentration; and

beeper means for outputting a sound corresponding to the detected carbon dioxide concentration in accordance with said control signal;

wherein said beeper means outputs an intermittent sound for each respiration in response to said control signal, said intermittent sound having a predetermined number of delay intervals, each of said concentration ranges having an associated intermittent sound with a predetermined number of delay intervals.

2. The capnometer according to claim 1, wherein said beeper means comprises means for converting a level of said concentration signal into a frequency corresponding to the level, said beeper means outputting a sound for each respiration in response to said control signal, said sound having a predetermined frequency, each of said concentration ranges having an associated predetermined frequency.

3. The capnometer according to claim 1, wherein said beeper means includes means for converting a level of said concentration signal into a frequency corresponding to the level, and outputs a sound for each expiration, said sound corresponding to the change of the detected carbon dioxide concentration.

4. The capnometer according to claim 1, wherein said carbon dioxide concentration calculating means includes an infrared rays detector.

5. The capnometer according to claim 4, wherein said infrared rays detector includes a thermopile.

6. A method for calculating the carbon dioxide concentration from a respiration gas, comprising the steps of:

detecting a concentration signal corresponding to a detected carbon dioxide concentration for each expiration;

comparing said concentration signal with concentrations respectively corresponding to a plurality of predetermined concentration ranges;

outputting a control signal, from among different control signals respectively corresponding to said predetermined concentration ranges, corresponding to said detected carbon dioxide concentration; and

outputting a sound corresponding to the detected carbon dioxide concentration, in accordance with said control signal;

wherein said step of outputting a sound comprises the step of outputting said sound which includes an intermittent sound for each respiration in response to said control signal, said intermittent sound having a predetermined number of delay intervals, each of said concentration ranges having an associated intermittent sound with a predetermined number of delay intervals.

7. The method according to claim 6, further comprising the steps of:

converting a level of said concentration signal into a frequency corresponding to the level;

wherein said sound for each expiration is in response to said control signal, and said sound has a predetermined frequency, each of said concentration ranges having an associated predetermined frequency.

8. The method according to claim 6, further comprising the steps of:

converting a level of said concentration signal into a frequency corresponding to the level; and

outputting a sound for each expiration, said sound corresponding to the change of the detected carbon dioxide concentration.