Method for controlling the respirating phase in a ventilating apparatus

• US 5,797,393 A
• Filed: 05/03/1996
• Issued: 08/25/1998
• Est. Priority Date: 05/05/1995
• Status: Expired due to Term

• Current Assignee: Dragerwerk AG & Company KGaA (FPS Vermögensverwaltung GmbH)
• Original Assignee: Dragerwerk AG
• Inventors: Kohl, Hans-Joachim
• Primary Examiner(s): Yu, Mickey
• Assistant Examiner(s): SRIVASTAVA, VIRENDRA KUMAR
• Application Number:
  US08/642,761
• Time in Patent Office: 844 Days
• Field of Search: 128/204.21, 128/204.22, 128/205.11, 128/204.18, 128/204.23
• US Class Current: 128/204.23
• CPC Class Codes: A61M 16/00 Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes stimulating the respiratory movement by mechanical, pneumatic or electrical means, iron lungs combined with gas breathing means A61H31/00
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 16/204 used for inhalation control
• CPC Class Codes: A61M 16/205 used for exhalation control
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/0042 in the expiratory circuit
• CPC Class Codes: A61M 2016/102 Measuring a parameter of the content of the delivered gas
• CPC Class Codes: A61M 2230/43 Composition of exhalation

Abstract

The invention is directed to a method for adjusting the respirating pressure during respirating phases in a ventilating apparatus. The method is improved by providing for a volume-controlled ventilation under the conditions of pressure-controlled ventilation as well as allowing for self-respiratory activity. The method includes the steps of: fixing a respirating volume desired value V_TS and an inhalation pressure desired value P_IS ; actuating the inhalation valve during inhalation in a first inhalation stroke to adjust the inhalation pressure P_I to the inhalation pressure desired value P_IS ; comparing the respiratory volume V_T to the respirating volume desired value V_TS and, if the respirating volume V_T is less than the respirating volume desired value V_TS, then, during the next inhalation stroke following the first inhalation stroke, incrementally increasing the inhalation pressure desired value P_IS by a pressure increment ΔP until the respirating volume V_T is greater than or equal to the respirating volume desired value V_TS ; and, during each inhalation, comparing the inhalation pressure P_I to the inhalation pressure desired value P_IS and, if the inhalation pressure P_I increases to a value greater than P_IS because of an intended exhalation, then, opening the exhalation valve to an extent so that the inhalation pressure desired value P_IS is reestablished as the inhalation pressure P_I.

Claims

1. A method for adjusting the respiratory pressure during respirating phases in a ventilating apparatus including:

an inhalation line;

an exhalation line;

a respiratory flow sensor for measuring the respirating volume V_T ;

an inhalation pressure sensor for measuring the inhalation pressure P_I ;

an inhalation valve for adjusting the respirating gas flow;

an exhalation valve for adjusting a preselected exhalation pressure P_ES in said exhalation line; and

, a central control unit; and

, the method comprising the steps of;

fixing a respirating volume desired value V_TS ;

fixing an inhalation pressure desired value P_IS for a first inhalation stroke as a start value;

actuating said inhalation valve during said first inhalation stroke to adjust said inhalation pressure P_I to said inhalation pressure desired value P_IS ;

comparing said respiratory volume V_T at the end of said first inhalation stroke to said respirating volume desired value V_TS and, if said respirating volume V_T is less than said respirating volume desired value V_TS, then,

during the subsequent inhalation strokes following said first inhalation stroke, incrementally increasing, in a stepwise manner, said inhalation pressure desired value P_IS by a pressure increment Δ

P in each of said subsequent inhalation strokes until said respirating volume V_T is greater than or equal to said respirating volume desired value V_TS ; and

,

during each inhalation stroke, comparing continuously said inhalation pressure P_I to said inhalation pressure desired value P_IS and, if said inhalation pressure P_I increases to a value greater than P_IS because of an intended exhalation, then,

opening said exhalation valve to an extent so that said inhalation pressure desired value P_IS is reestablished as said inhalation pressure P_I.

2. A method for adjusting the respiratory pressure during respirating phases in a ventilating apparatus including:

an inhalation line;

an exhalation line;

a respiratory flow sensor for measuring the respirating volume V_T ;

an exhalation pressure sensor for measuring the exhalation pressure P_E ;

an exhalation valve for adjusting a preselected exhalation pressure P_ES in said exhalation line; and

, a central control unit; and

, the method comprising the steps of;

fixing a respirating volume desired value V_TS ;

fixing an inhalation pressure desired value P_IS for a first inhalation stroke as a start value;

actuating said inhalation valve during said first inhalation stroke to adjust said inhalation pressure P_I to said inhalation pressure desired value P_IS ;

comparing said respiratory volume V_T at the end of said first inhalation stroke to said respirating volume desired value V_TS and, if said respirating volume V_T is less than said respirating volume desired value V_TS, then,

during the subsequent inhalation strokes following said first inhalation stroke, incrementally increasing said inhalation pressure desired value P_IS in a stepwise manner by a pressure increment Δ

P in each of said subsequent inhalation strokes until said respirating volume V_T is greater than or equal to said respirating volume desired value V_TS ;

during each inhalation stroke, comparing continuously said inhalation pressure P_I to said inhalation pressure desired value P_IS and, if said inhalation pressure P_I increases to a value greater than P_IS because of an intended exhalation, then,

opening said exhalation valve to an extent so that said inhalation pressure desired value P_IS, is reestablished as said inhalation pressure P_I ; and

,

during an exhalation, comparing the exhalation pressure P_E to the preselected exhalation pressure P_ES and, if said exhaled pressure P_E assumes a value less than said preselected exhalation pressure P_ES because of an intended inhalation, then;

increasing the respirating gas flow with said inhalation valve so as to cause said exhalation pressure P_E to again at least reach said preselected exhalation pressure P_ES.

3. A method for adjusting the respiratory pressure during respirating phases in a ventilating apparatus including:

an inhalation line;

an exhalation line;

a respiratory flow sensor for measuring the respirating volume V_T ;

an exhalation pressure sensor for measuring the exhalation pressure P_E ;

an inhalation valve for adjusting the respirating gas flow;

an exhalation valve for adjusting a preselected exhalation pressure P_ES in said exhalation line; and

, a central control unit; and

, the method comprising the steps of;

fixing a respirating volume desired value V_TS and an inhalation pressure desired value P_IS ;

during an inhalation, adjusting the inhalation pressure P_I to said inhalation pressure desired value P_IS by actuating said inhalation valve; and

,

during an exhalation, determining said respirating volume V_T and comparing said respirating volume V_T to said respirating volume desired value V_TS and, if said respirating volume V_T is less than said respirating volume desired value V_TS, then,

during a subsequent exhalation, reducing said preselected exhalation pressure P_ES by predetermined pressure increments Δ

P with each exhalation until said respiratory volume desired value V_TS is reached.