摘要:
An ultrasound meter (2) comprising a transmitter (10), a receiver (14) and a control unit (12)for the transmitter (10) is disclosed. In order to improve measurements a feed-back connection (18) is disposed between the control unit (12) and the receiver (14) for a signal from the receiver (14) to the control unit (12) and the control unit (12) is adapted to regulate energy to the transmitter (10) in dependence of the signal fed back from the receiver (14) so that a constant output signal is obtained from the receiver (14).
摘要:
A high frequency oscillator (HFO) ventilator comprises an oscillator unit (2) for alternately supplying to and removing from a proximal end of a gas conduit (6,10,14,16) a volume of gas ("oscillator volume") at a predetermined high frequency; a gas conduit (6,10,14,16) having a proximal end (4) connectable to the oscillator unit (2) and a distal end (18) connectable with the patient's airways; and located between the proximal end (4) and the distal end (18), an inlet (24) for receiving a continuous flow of a bias gas from a supply (26) and an outlet (20) characterised in that the ventilator further comprises a flow controller (38,40) adapted to apportion between the distal end (18) of the conduit (6,10,14,16) and the outlet (20) the volume of gas supplied by the oscillator unit (2) to establish a predetermined inspiration tidal volume for delivery to the patient's airways independent of the oscillator volume.
摘要:
A high frequency oscillator (HFO) ventilator (2) comprises a gas conduit (26,6) having an opening (30) for gas connection with a patient's airways and a bias gas flow inlet (34) and outlet (10) disposed to define therebetween a bias gas flow-path within the conduit (26,6). An oscillator (16) is operable to induce pressure oscillations in gas within the conduit (26,6) to move a volume of gas ("tidal volume") along a respiration flow-path, intersecting the bias gas flow-path, alternately in to and out of the opening (30) at a predetermined high frequency to provide respectively an inspiration phase and an expiration phase of a breathing cycle. The HFO ventilator (2) further comprises an extraction device (38,44) operable during the breathing cycle, and preferably in timed relation with the operation of the oscillator (16), to withdraw an additional amount of gas from the respiration flow-path.
摘要:
A method for controlling an expiratory valve in a ventilator during expiration (E). An optimum system is using method steps comprising a method stage in which the expiratory valve is opened almost completely for a first interval (t1) and measurement during the first interval (t1) of flow or pressure in the expiratory part of the ventilator, determining when the flow or pressure in the expiratory part meets a condition, starting a second interval (t2) when the flow in the expiratory part meets the condition and regulating the expiratory valve during the second interval (t2) in order to attain a pre-set end pressure (PEEP) in the expiratory section.
摘要:
A temporally isolated portion of a digital representation of a time-domain electrical signal originating from the atria of a patient is frequency analysed by analyser (14) to provide a corresponding frequency spectrum. A comparator (16) is arranged to compare the obtained frequency spectrum with a template frequency spectrum, selectively adapted (18) dependent on previously obtained frequency spectra from different temporally isolated portions, to determine a frequency shift value and an amplitude value optimising a correlation between the two spectra. An output representing the two determined values is used by an event classification means (22,24), preferably together with parameters describing the template frequency spectrum, to classify an atrial arrhythmia manifest in the digital representation.
摘要:
A patient ventilator system (19) comprises a high frequency oscillation ventilator (1,4,5,6) connectable to a patient circuit (2,3) and operable to induce oscillations within gas in the circuit (2,3) at a predetermined high frequency and a gas supply (7) connectable to the patient circuit (2,3) for supplying breathing gas thereto; A detection device (14,15,16) is also included within the ventilator system (19) and is adapted to monitor during the operation of the high frequency oscillator ventilator (1,4,5,6) one or both gas pressure and gas flow to detect a variation therein not derived from the induced high frequency oscillations and to output a trigger signal (13) dependent on the detected variation indicating a spontaneous breathing effort; and in that gas supply (7) is operable on receipt of the trigger signal (13) to supply breathing gas into the circuit (2,3) at a level to assist the spontaneous breathing effort.