276 results about "Airway pressures" patented technology

A method for controlling breathing gas flow of a ventilator for assisted or controlled ventilation of a patient as a function of a tracheobronchial airway pressure of the patient. A ventilator tube, such as a tracheal tube or tracheostomy tube, can be introduced into a trachea of the patient and subjected to the breathing gas, and has an inflatable cuff and at least one lumen that is continuous from a distal end of the tube to a proximal end of the tube. An apparatus detects an airway pressure, in which the tracheobronchial airway pressure is ascertained by continuous or intermittent detection and evaluation of an intra-cuff pressure prevailing in the cuff of the tube inserted into the trachea. The breathing gas flow of the ventilator is controlled as a function of the intra-cuff pressure detected.

The present disclosure relates, in some embodiments, to devices, systems, and/or methods for collecting, processing, and/or displaying stroke volume and/or cardiac output data. For example, a device for assessing changes in cardiac output and/or stroke volume of a subject receiving airway support may comprise a processor; an airway sensor in communication with the processor, wherein the airway sensor is configured and arranged to sense pressure in the subject's airway, lungs, and/or intrapleural space over time; a blood volume sensor in communication with the processor, wherein the blood volume sensor is configured and arranged to sense pulsatile volume of blood in a tissue of the subject over time; and a display configured and arranged to display a representative of an airway pressure, a pulsatile blood volume, a photoplethysmogram, a photoplethysmogram ratio, the determined cardiac output and/or stroke volume, or combinations thereof. A method of assessing changes in cardiac output or stroke volume of a subject receiving airway support from a breathing assistance system may comprise sensing pressure in the subject's airway as a function of time, sensing pulsatile volume of blood in a tissue of the subject as a function of time, producing a photoplethysmogram from the sensed pulsatile volume, determining the ratio of the amplitude of the photoplethysmogram during inhalation to the amplitude of the photoplethysmogram during exhalation, and determining the change in cardiac output or stroke volume of the subject using the determined ratio.

A method and system of individually controlling positive airway pressure of a patient's nares. Some exemplary embodiments may be a method comprising applying therapeutic gas pressure within a first naris of a patient during respiration, and applying therapeutic gas pressure within a second naris of the patient during the respiration. The therapeutic gas pressures applied to each naris are different.

Method and apparatus for non-invasively determining the time onset (Tonset) and end (Tend) of patient inspiratory efforts. A composite pressure signal is generated comprising the sum of an airway pressure signal, a gas flow pressure signal obtained by applying a gain factor (Kf) to a signal representing gas flow rate and a gas volume pressure signal obtained by applying a gain factor (Kv) to a signal representing volume of gas flow. Kf and Kv values are adjusted to result in a desired linear trajectory of composite pressure signal baseline in the latter part of the exhalation phase. The current composite pressure signal is compared with (i) selected earlier composite pressure signal values and/or (ii) value expected at current time based on extrapolation of composite pressure signal trajectory at specified earlier times and/or (iii) the current rate of change in the composite pressure signal with a selected earlier rates of change. The differences obtained by the comparison are compared with selected threshold values. Tonset is identified when at least one of the differences exceeds the threshold values.

Improved methodology and apparatus for the clinical study and treatment of sleep apnea which incorporates one or more of the following features: (1) application of mono-level, alternating high and low level, or variable positive airway pressure generally within the airway of the patient with the mono-level, high and low level, or variable airway pressure generally being coordinated with and/or responsive to the spontaneous respiration of the patient, (2) usage of adjustably programmable pressure ramp circuitry capable of producing multiple pressure ramp cycles of predetermined duration and pattern whereby the ramp cycles may be customized to accommodate the specific needs of an individual sleep apnea patient so as to ease the patient's transition from wakefulness to sleep, (3) remote control or patient-sensed operation of the apparatus, (4) employment of safety circuitry, reset circuitry and minimum system leak assurance circuitry, controls and methods, and (5) utilization of clinical control circuitry whereby sleep disorder data may be compiled and appropriate therapy implemented during a one-night sleep study.

A gas administering method for administering gas to an airway of a patient having a nasal vestibule and for use with a gas administering apparatus comprises a primary gas source that is operable to provide gas and a nasal vestibular portion arranged so as to receive the gas from the primary gas source. Further, the nasal vestibular portion is capable of releasing the primary gas into the nasal vestibule. The method comprises inserting the nasal vestibular portion into the nasal vestibule, forming a seal between the nasal vestibular portion and an inner surface of the nasal vestibule, administering an amount of a gas from the primary gas source at a constant flow rate into the nasal vestibule via the nasal vestibular portion, and administering an anesthetic to the patient. The anesthetic induces depression of a portion of the nervous system of the patient. Furthermore, the seal promotes airway pressure buildup that is sufficient to prevent obstruction of the airway during depression of at least a portion of the nervous system and prevents escape of the gas from between the nasal vestibule and the nasal vestibular portion.

Systems and methods may include a gas source, a gas delivery circuit, and a nasal interface allowing breathing ambient air through the nasal interface. A gas flow path through the nasal interface may have a distal gas flow path opening. A nozzle may be associated with a proximal end of the nasal interface a distance from the distal end gas flow path opening. At least a portion of an entrainment port may be between the nozzle and the distal end gas flow opening. The nozzle may deliver gas into the nasal interface to create a negative pressure area in the gas flow path at the entrainment port. The nasal interface and the nozzle may create a positive pressure area between the entrainment port and the distal end gas flow path opening. Gas from the gas delivery source and air entrained through the entrainment port may increase airway pressure or lung pressure or provide ventilatory support.

An out flow resistance switching ventilator and its methodology for providing mechanical ventilation support to the respiratory failure patient are claimed. Based on the continuous out flow impounding ventilation mechanism, the apparatus provides ventilation by switching flow resistance between two different levels at a continuous gas flow system outlet valve controlled by patient's spontaneous breathing or preset mandatory parameters, resulting in airway pressure levels switching, and therefore creating lung volume switching, which is totally different from either volume ventilation or pressure ventilation mechanism utilized in the current conventional ventilators.

The invention provides an improved ventilation method and method for controlling a ventilator apparatus in accordance with same. More specifically, the present invention relates to a method of controlling a ventilator apparatus comprising the steps of placing a ventilator in a mode capable of adjusting airway pressure (P) and time (T), monitoring expiratory gas flow, analyzing the expiratory gas flow over time (T) to establish an expiratory gas flow pattern, and setting and/or adjusting a low time (T2) based on the expiratory gas flow pattern. Alternatively, the present invention relates to a method of controlling a ventilator apparatus comprising the steps of placing a ventilator in a mode capable of adjusting airway pressure (P) and time (T), and setting a low airway pressure (P2) of substantially zero cmH₂O.

A method of automatically controlling a respiration system for proportional assist ventilation with a control device and with a ventilator. An electrical signal is recorded by electromyography with electrodes on the chest in order to obtain a signal u_emg(t) representing the breathing activity. The respiratory muscle pressure p_mus(t) is determined by calculating it in the control unit from measured values for the airway pressure and the volume flow Flow(t) as well as the patient's lung mechanical parameters. The breathing activity signal u_emg(t) is transformed by means of a preset transformation rule into a pressure signal p_emg(u_emg)(t)) such that the mean deviation of the resulting transformed pressure signal p_emg(t) from the respiratory muscle pressure p_mus(t) is minimized. The respiratory effort pressure p_pat(t) is determined as a weighted mean according to p_pat(t)=a·p_mus(t)+(1−a)·p_emg(t), where a is a parameter selected under the boundary condition 0≦a≦1. The airway pressure p_aw(t) to be delivered is calculated as a function of preselected degrees of assist VA (Volume Assist) and FA (Flow Assist) by sliding adaptation as

wherein t_i is a current point in time and t_i−j, wherein j=1, . . . , n, are previous points in time of a periodical time-discrete sampling, and k_j and h_j, wherein j=1, . . . , n are parameters dependent on resistance (R), elastance (E), positive end-expiratory pressure (PEEP), intrinsic PEEP (iPEEP), Volume Assist (VA) and Flow Assist (FA) and the sampling time Δt, and the ventilator is set by the control unit so as to provide this airway pressure p_aw(t_i)

A non-invasive ventilation system may include an interface. The interface may include at least one gas delivery jet nozzle adapted to be positioned in free space and aligned to directly deliver ventilation gas into an entrance of a nose. The at least one gas delivery jet nozzle may be connected to a pressurized gas supply. The ventilation gas may entrain ambient air to elevate lung pressure, elevate lung volume, decrease the work of breathing or increase airway pressure, and wherein the ventilation gas is delivered in synchrony with phases of breathing. A support for the at least one gas delivery jet nozzle may be provided. A breath sensor may be in close proximity to the entrance of the nose. A patient may spontaneous breathe ambient air through the nose without being impeded by the interface.

Respiratory support and/or controlled mechanical ventilation of a patient are provided. A ventilation apparatus may include a ventilator, a transtracheal prosthesis, and a respiratory relief device. The transtracheal prostheses and ventilation catheter may be arranged such that the patient can breathe freely through the upper airway and/or the tracheal prostheses. Respiratory sensors may measure a breathing rate, lung pressure, airway pressure, or a combination thereof. Pulses of gas may be provided to the patient through the ventilation catheter during inspiration. The pulses may have a first volume while the patient breathes normal and a second volume when the sensors detect a cessation of breathing or reduction in breathing volume. The second volume may be provided at 1-5 times the normal breathing rate, with a volume 25-500% times the first volume, or both.

A system and a method for circuit compliance compensated pressure control in a patient respiratory ventilation system, having a pressure regulated feedback servo control loop, a pressure-regulated volume controller, and a patient volume observer. The patient volume observer is operative to estimate a patient volume, that is, the volume actually delivered to the patient by accounting for volume deviation or loss caused by patient circuit leakage and valve dynamics. Based on the difference between the estimated patient volume and a set tidal volume, the pressure-regulated volume controller is operative to generate and update a circuit compliance pressure compensation factor. The pressure regulated feedback servo control loop is operative to modulate the peak airway pressure based on the circuit compliance pressure compensation factor, so as to achieve the set tidal volume while maintaining a constant inspiratory time and a constant I:E ratio.

A method of creating a non-invasive predictor of both physiologic and imposed patient effort from airway pressure and flow sensors attached to the patient using an adaptive mathematical model. The patient effort is commonly measured via work of breathing, power of breathing, or pressure-time product of esophageal pressure and is important for properly adjusting ventilatory support for spontaneously breathing patients. The method of calculating this non-invasive predictor is based on linear or non-linear calculations using multiple parameters derived from the above-mentioned sensors.