초록 ▼

In a method and breathing apparatus for providing support ventilation to a spontaneously breathing patient a pressure and/or a flow is monitored based on pressure and/or flow measurements, and efforts to inhale or exhale by the patient are detected based on changes in the monitored pressure and/or f

In a method and breathing apparatus for providing support ventilation to a spontaneously breathing patient a pressure and/or a flow is monitored based on pressure and/or flow measurements, and efforts to inhale or exhale by the patient are detected based on changes in the monitored pressure and/or flow. When a change in the monitored pressure and/or flow indicating an effort to inhale or exhale is detected, the rate of that change is determined and used to calculate a suitable rate of change of pressure applied to the airways of the patient. By changing the applied pressure in accordance with the so determined suitable rate of change, the pressure rise time during inspiration and/or the pressure fall time during expiration can be adjusted to the needs of the patient to ensure efficient and comfortable ventilation.

대표청구항 ▼

1. A breathing apparatus for providing support ventilation to a spontaneously breathing patient, comprising: a pressure regulator that regulates a pressure applied to airways of the patient;at least one pressure and/or flow sensor for obtaining pressure and/or flow measurements that are dependent on

1. A breathing apparatus for providing support ventilation to a spontaneously breathing patient, comprising: a pressure regulator that regulates a pressure applied to airways of the patient;at least one pressure and/or flow sensor for obtaining pressure and/or flow measurements that are dependent on pressure or flow in the airways of the patient;a control computer configured to monitor a pressure and/or flow based on said pressure and/or flow measurements;the control computer being configured to detect a transition that occurs at a trigger point time between inhalation and exhalation by the patient or between exhalation and inhalation by the patient, based on a change in the monitored pressure and/or flow that occurs before said trigger point time;the control computer being further configured to:determine a suitable rate of change in the pressure applied to the patient based on the rate of the change in the monitored pressure and/or flow; andcontrol the pressure regulator to change the applied pressure at or following said trigger point time in accordance with said suitable rate of change in response to said transition. 2. Breathing apparatus according to claim 1, wherein the control unit is configured to determine the suitable rate of change in applied pressure and to control the pressure regulator to change the applied pressure in accordance with said suitable rate of change on a breath-by breath basis. 3. Breathing apparatus according to claim 1, wherein the control unit is configured to change the applied pressure in accordance with the suitable rate of change upon detection of a trigger point, and to determine the suitable rate of change in applied pressure before detection of said trigger point. 4. Breathing apparatus according to claim 1, wherein the control unit is configured to determine the suitable rate of change in applied pressure also based on a change in the rate of change in the monitored pressure and/or flow. 5. Breathing apparatus according to claim 1, wherein the control unit is configured to control the pressure regulator to apply a substantially constant expiratory target pressure level at a end of an expiratory phase and a substantially constant inspiratory target pressure level at a end of an inspiratory phase, and to change the applied pressure between the expiratory target pressure level and the inspiratory target pressure level in accordance with said suitable rate of change. 6. Breathing apparatus according to claim 5, wherein the control unit is configured to determine a suitable rate of change in applied pressure which varies in time and accelerates during a first time period of an initial phase of the inspiratory or expiratory phase and decelerates during a second time period of the initial phase of the inspiratory or expiratory phase. 7. Breathing apparatus according to claim 1, wherein the control unit is configured to determine a basic value for the suitable rate of change in the applied pressure, fit a pressure curve to a straight line having a slope corresponding to said basic value, and change the applied pressure in accordance with said pressure curve. 8. A method for providing support ventilation to a spontaneously breathing patient, comprising: placing airways of a patient in communication with a pressure regulator, operating the pressure regulator so as to regulate a pressure applied to the airways of the patient;in a control computer, monitoring a pressure and/or flow based on pressure and/or flow measurements that are dependent on pressure or flow in the airways of the patient;in said control computer, detecting a transition that occurs at a trigger point time between inhalation and exhalation by the patient or between exhalation and inhalation by the patient, based on a change in the monitored pressure and/or flow that occurs before said trigger point time;in said control computer, determining a rate of change in a pressure applied to the patient based on the rate of the change in the monitored pressure and/or flow; andin said control computer generating control signals, and emitting control signals to said pressure regulator, in order to operate the pressure regulator so as to change the applied pressure at or following said trigger point time in accordance with said suitable rate of change in response to said effort to inhale or exhale. 9. Method according to claim 8, wherein said method is performed on a breath-by breath basis. 10. Method according to claim 8, comprising detecting a trigger point indicating that the patient has made an effort to inhale or exhale and changing the applied pressure upon detection of said trigger point, the determination of the suitable rate of change in applied pressure being made prior to detection of said trigger point. 11. Method according to claim 8 comprising making the determination of the suitable rate of change in applied pressure also based on a change in the rate of change in the monitored pressure and/or flow. 12. Method according to claim 8 comprising: applying a substantially constant expiratory target pressure level at the end of an expiratory phase;applying a substantially constant inspiratory target pressure level at the end of an inspiratory phase; andchanging the applied pressure between the expiratory target pressure level and the inspiratory target pressure level in accordance with said suitable rate of change. 13. Method according to claim 12, comprising changing the applied pressure such that the rate of change accelerates during a first time period of an initial phase of the inspiratory or expiratory phase and decelerates during a second time period of the initial phase of the inspiratory or expiratory phase. 14. Method according to claim 8, further comprising: determining a basic value for the suitable rate of change in the applied pressure;fitting a pressure curve (IPC, EPC) to a straight line having a slope corresponding to said basic value; andchanging the applied pressure in accordance with said pressure curve (IPC, EPC). 15. A non-transitory, computer-readable data storage medium encoded with programming instructions, said storage medium being loaded into a computerized processor of a breathing apparatus that provides support ventilation to a spontaneously breathing patient, said breathing apparatus also comprising a pressure regulator that is in communication with airways of the patient, and at least one pressure and/or flow sensor, said programming instructions causing said computerized control unit to: operate the pressure regulator to regulate a pressure applied to the airways of the patient;monitor a pressure and/or flow based on pressure and/or flow measurements made by said sensor that are dependent on pressure or flow in the airways of the patient;detect a transition that occurs at a trigger point time between inhalation and exhalation by the patient or between exhalation and inhalation b the patient, based on a change in the monitored pressure and/or flow that occurs before said trigger point time;determine a rate of change in a pressure applied to the patient based on the rate of the change in the monitored pressure and/or flow; andoperate the pressure regulator to change the applied pressure at or following said trigger point time in accordance with said suitable rate of change in response to said effort to inhale or exhale.