摘要:
A control unit for a ventilator is arranged to receive, from each of a number of electrode pairs on an esophageal catheter a bioelectric signal having an ECG component. The control unit has a calculating unit that determines the ECG component of each of the bioelectric signals and a position unit that determines the position of the catheter in relation to the patient's diaphragm based on a comparison the amplitudes of ECG components of the bioelectric signals.
摘要:
A control unit for a ventilator is arranged to receive, from each of a number of electrode pairs on an esophageal catheter a bioelectric signal having an ECG component. The control unit has a calculating unit that determines the ECG component of each of the bioelectric signals and a position unit that determines the position of the catheter in relation to the patient's diaphragm based on a comparison the amplitudes of ECG components of the bioelectric signals.
摘要:
In a method and device for positioning a linear array of electrodes mounted on a distal end section of an elongated flexible member in a patient's respiratory airways at the level of the patient's diaphragm, a length of the elongated flexible member pre-determined to position the linear array of electrodes at the level of the patient's diaphragm is inserted through the patient's respiratory airways. Signals representative of an electrical activity of the patient's diaphragm (EAdi) are detected through the electrodes of the linear array, a presence or absence of ECG signal components is detected in the EAdi signals, and the position of the linear array of electrodes in the patient's respiratory airways is detected in response to the presence or absence of the ECG signal components in the EAdi signals. Also, lower esophageal sphincter activity may be detected in the EAdi signals, and the position of the linear array of electrodes in the patient's respiratory airways determined in response to the detected lower esophageal sphincter. Finally, an end-expiratory occlusion of the patient's respiratory airways may be performed to verify that the electrical activity of the diaphragm coincides with a negative deflection of the patient's respiratory airways pressure again in view of determining adequate positioning of the linear array of electrodes.
摘要:
In a method and device for positioning a linear array of electrodes mounted on a distal end section of an elongated flexible member in a patient's respiratory airways at the level of the patient's diaphragm, a length of the elongated flexible member pre-determined to position the linear array of electrodes at the level of the patient's diaphragm is inserted through the patient's respiratory airways. Signals representative of an electrical activity of the patient's diaphragm (EAdi) are detected through the electrodes of the linear array, a presence or absence of ECG signal components is detected in the EAdi signals, and the position of the linear array of electrodes in the patient's respiratory airways is detected in response to the presence or absence of the ECG signal components in the EAdi signals. Also, lower esophageal sphincter activity may be detected in the EAdi signals, and the position of the linear array of electrodes in the patient's respiratory airways determined in response to the detected lower esophageal sphincter. Finally, an end-expiratory occlusion of the patient's respiratory airways may be performed to verify that the electrical activity of the diaphragm coincides with a negative deflection of the patient's respiratory airways pressure again in view of determining adequate positioning of the linear array of electrodes.
摘要:
A ventilator intended to be connected to a patient for breathing therapy has a control unit having an input for receiving EMG signals from an EMG detector and an output for an EMG based control signal and a pneumatic unit for generating breathing gas flows dependent on the EMG based control signal is described. The ventilator has a detector for determining a parameter related to breathing dynamics for the patient, this detector being connected to the control unit and control unit controlling the pneumatic unit dependent on the parameter related to breathing dynamics in the case of loss of EMG signals at the input.
摘要:
A ventilator intended to be connected to a patient for breathing therapy has a control unit having an input for receiving EMG signals from an EMG detector and an output for an EMG based control signal and a pneumatic unit for generating breathing gas flows dependent on the EMG based control signal is described. The ventilator has a detector for determining a parameter related to breathing dynamics for the patient, this detector being connected to the control unit and control unit controlling the pneumatic unit dependent on the parameter related to breathing dynamics in the case of loss of EMG signals at the input.
摘要:
In a method for controlling an expiratory valve in a ventilator during expiration, the expiratory valve is opened substantially fully for a first interval. Fully opening the expiratory valve has the advantage of minimizing the expiratory resistance a patient needs to overcome. Keeping the expiratory valve open as long as possible during expiration, without losing control of positive end expiratory pressure (PEEP), is therefore advantageous. An optimal system is achieved. In a method wherein pressure in the expiratory section of the ventilator is measured during a second interval, the expiratory valve is regulated so a predetermined end pressure is obtained in the expiratory section, and at least one parameter, directly or indirectly related to control of the expiratory valve, is determined, and a determination is made from that parameter as to whether the next first interval for the next expiration should be longer than, shorter than or as long as the first interval.
摘要:
A method of obtaining an indication of the position of an esophageal catheter inserted into a patient includes the steps of obtaining an electrical signal from the esophageal catheter, determining an ECG component of the electrical signal, determining the widths and/or rate of a number of periods in which the ECG component exceeds a threshold value, using the rate or widths of the periods to determine the presence of a P-wave in the ECG component, and concluding that the catheter is in a good position for obtaining a correct EMG signal if a P-wave is determined to be present. If not, the position may be corrected. The method may be performed by a control unit in a ventilator or a monitoring device.
摘要:
A method and apparatus for filtering an electromyogram (EMG) signal from a raw signal which includes a contribution from an electrocardiogram (EKG) signal is disclosed. The method includes the steps of estimating an attribute (such as a Fourier transform) of both the EMG contribution to the raw signal and the EKG contribution to the raw signal and, dependent on both frequency spectrums, determining an EMG window in a frequency range and obtaining the EMG signal by passing it through a filter defined by the frequency range. The method is particularly used when monitoring a multi-channel electrical recording from a plurality of electrodes attached to a patient's diaphragm.
摘要:
A valve assembly HAS an element movable in a mechanical journal arrangement relative to a valve opening to establish an opening position of a valve, and A control unit for controlling the application of an oscillatory electromagnetic force to the element (8) having an known peak amplitude to cause the element to execute a sympathetic oscillatory motion as a friction reducing maneuver. The control unit is adapted to control the peak amplitude of the oscillatory electromagnetic force to sequentially apply a number of different peak amplitudes, each during a different measurement period. A monitor detects changes in the opening position of the valve during each of the measurement periods and provides a measure thereof. A processor is connected to the control unit and to the monitor to determine a working amplitude of the oscillatory electromagnetic force at which the detected changes will be minimized and to supply the determined working amplitude to the control unit.