Apparatus for the monitored metering of no into patients' respiratory air

• US 5,531,218 A
• Filed: 04/12/1994
• Issued: 07/02/1996
• Est. Priority Date: 04/17/1993
• Status: Expired due to Fees

• Current Assignee: INO Therapeutics GmbH
• Original Assignee: Messer Griesheim GmbH
• Inventors: Krebs, Christian
• Primary Examiner(s): Lewis, Aaron J.
• Application Number:
  US08/226,550
• Time in Patent Office: 812 Days
• Field of Search: 128/200.14, 128/200.23, 128/203.12, 128/202.22, 128/203.25
• US Class Current: 128/203.12
• CPC Class Codes: A61M 16/10 Preparation of respiratory gases or vapours
• CPC Class Codes: A61M 16/12 by mixing different gases
• CPC Class Codes: A61M 2016/102 Measuring a parameter of the content of the delivered gas
• CPC Class Codes: A61M 2202/0275 Nitric oxide [NO]
• CPC Class Codes: A61M 2205/70 with testing or calibration facilities
• CPC Class Codes: G01N 33/0037 for NOx
• CPC Class Codes: G01N 33/497 of gaseous biological material, e.g. breath
• CPC Class Codes: G05D 11/138 by sensing the concentration of the mixture, e.g. measuring pH value
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

Abstract

Apparatus for the monitored metering of NO into patients'"'"' respiratory air

An apparatus for the monitored metering of NO into the respiratory air of patients with ARDS or similar disorders essentially comprises a respirator (1), an NO metering container (3), a metering unit (4), an analyzer (2) for determining the concentration of NO in the patient'"'"'s respiratory air and a control unit (6a) which acts on the metering unit. In order for the apparatus to operate fault-free on continuous operation and quickly respond to changes in the NO concentration, a dehumidifier (23) and a measurement gas pump (20) are located in the connecting line between analyzer and respirator. An NO limit monitoring unit (18) which acts on the metering unit and is connected to the analyzer is preferably provided. It is furthermore advantageous for a monitoring and automatic control unit (6b) to be responsible for adjusting the NO to be metered by determining the volumetric flows of respiratory gas and NO on the basis of the analyzed value of NO. FIG. 1.

Claims

1. An apparatus for the monitored metering of NO (nitric oxide) into patients'"'"' respiratory air, comprising

a) a respirator communicating with passageway means for leading to a patient,

b) an NO metering container which is connected to said passageway means for supplying NO to the respiratory air supplied to a patient,

c) a-metering unit arranged between the respirator and the NO metering container,

d) an analyzer connected to said passageway means leading from the respirator to a patient for determining the concentration of NO in a patient'"'"'s respiratory air,

e) a control unit which is connected to the analyzer and acts on the metering unit to control the amount of flow of NO from the NO container to a patient,

f) a dehumidifier located in a connecting line between the respirator and the analyzer, and

g) a measurement gas pump located in the connecting line between the analyzer and the dehumidifier.

2. An apparatus as claimed in claim 1 wherein the NO metering container is connected to the respiratory arm of the respirator.

3. An apparatus as claimed in claim 2, wherein the dehumidifier is a measurement gas condenser.

4. An apparatus as claimed in claim 3, wherein the analyzer is designed as an apparatus operating on the principle of the measurement of infrared absorption or with electrochemical sensors.

5. An apparatus as claimed in claim 3, wherein the analyzer is designed as a chemiluminescence detector.

6. An apparatus as claimed claim 5, which has an NO limit monitoring unit which is connected to the analyzer and acts on the control unit.

7. An apparatus as claimed in claim 6, which has devices for measuring the inspiration volumetric flow of respiratory air and oxygen, the NO volumetric flow, and a monitoring and automatic control unit in which the measured NO volumetric flow and the analyzed value is fed back as controlled variable for adjusting the amount of NO metered in.

8. An apparatus as claimed in claim 1, wherein the dehumidifier is a measurement gas condenser.

9. An apparatus as claimed in claim 8, wherein the analyzer is designed as an apparatus operating on the principle of the measurement of infrared absorption or with electrochemical sensors.

10. An apparatus as claimed in claim 8, wherein the analyzer is designed as a chemiluminescence detector.

11. An apparatus as claimed in claim 8, which has an NO limit monitoring unit which is connected to the analyzer and acts on the control unit.

12. An apparatus as claimed in claim 8, which has devices for measuring the inspiration volumetric flow of respiratory air and oxygen, the NO volumetric flow, and a monitoring and automatic control unit in which the measured NO volumetric flow and the analyzed value is fed back as controlled variable for adjusting the amount of NO metered in.

13. An apparatus as claimed in claim 1, wherein the analyzer is designed as an apparatus operating on the principle of the measurement of infrared absorption or with electrochemical sensors.

14. An apparatus as claimed in claim 13, which has an NO limit monitoring unit which is connected to the analyzer and acts on the control unit.

15. An apparatus as claimed in claim 13, which has devices for measuring the inspiration volumetric flow of respiratory air and oxygen, the NO volumetric flow, and a monitoring and automatic control unit in which the measured NO volumetric flow and the analyzed value is fed back as controlled variable for adjusting the amount of NO metered in.

16. An apparatus as claimed in claim 1, wherein the analyzer is designed as a chemiluminescence detector.

17. An apparatus as claimed in claim 16, which has an NO limit monitoring unit which is connected to the analyzer and acts on the control unit.

18. An apparatus as claimed in claim 16, which has devices for measuring the inspiration volumetric flow of respiratory air and oxygen, the NO volumetric flow, and a monitoring and automatic control unit in which the measured NO volumetric flow and the analyzed value is fed back as controlled variable for adjusting the amount of NO metered in.

19. An apparatus as claimed in claim 1, which has an NO limit monitoring unit which is connected to the analyzer and acts on the control unit.

20. An apparatus as claimed in claim 1, which has devices for measuring the inspiration volumetric flow of respiratory air and oxygen, the NO volumetric flow, and a monitoring and automatic control unit in which the measured NO volumetric flow and the analyzed value is fed back as controlled variable for adjusting the amount of NO metered in.

21. An apparatus as claimed in claim 1, wherein the analyzer analyzes the amount of NO being exhaled by a patient.

22. An apparatus as claimed in claim 21, wherein the analyzer also analyzes the amount of NO being inhaled by a patient.

23. An apparatus as claimed in claim 22, wherein the analyzer analyzes the amount of NO₂ (nitrogen dioxide) being exhaled by a patient.

24. An apparatus as claimed in claim 23, wherein the metering unit stops the flow of NO to the respirator when the amount of NO in the respiratory gas exceeds a predetermined level.

25. An apparatus as claimed in claim 21, wherein the analyzer analyzes the amount of NO₂ (nitrogen dioxide) being exhaled by a patient.

26. An apparatus as claimed in claim 1, wherein the metering unit stops the flow of NO to the respirator when the amount of NO in the respiratory gas exceeds a predetermined level.