Abstract: A first respiratory volume of the patient is determined during at least a part of the under-assisted breath. A second respiratory volume of the patient is determined during at least a part of the assisted breath, for a duration matching the part of the under-assisted breath. The first and second respiratory volumes may be measured for a same value of a neural respiratory drive of the patient. A volume assistance correction is calculated based on the first and second respiratory volumes. A pressure is measured at the mechanical ventilator or at an airway of the patient. A load of the respiratory system of the patient is calculated based on the volume assistance correction and on the measured pressure. The mechanical ventilator is controlled according to the load of the respiratory system of the patient and may implement a prediction for back-up use when the patient is not spontaneous breathing.

Abstract: A mechanical ventilation system comprises a plurality of ventilation therapy sub-systems. Each of the ventilation therapy sub-systems is adapted to assist a respiratory function of the patient. The system also comprises a detector of the respiratory drive of the patient, an operator interface receiving one or more control parameters, and a main controller. The main controller assigns a therapeutic contribution to each of the ventilation therapy sub-systems based on the respiratory drive of the patient and on the control parameters. The controller modulates the respiratory drive of a patient by controlling each of the plurality of the ventilation therapy sub-systems according to its assigned therapeutic contribution. Distinct ventilation therapy sub-systems may apply negative pressure on the abdomen of the patient, deliver a non-pressurizing inspiratory flow to the patient, or induce a positive pressure in the airways of the patient.

Abstract: A device for providing ventilatory assist to a patient has a manifold having an inspiratory port to receive an inspiratory flow from an inspiratory supply line, an interface port connectable to an external end of an endotracheal tube inserted in a patient's trachea and an expiratory port configured to receive an expiratory flow from the endotracheal tube via the interface port. An inspiratory lumen has a distal end insertable in the endotracheal tube. A cross-section of the inspiratory lumen is smaller than that of the endotracheal tube to allow gas flowing in the endotracheal tube. The inspiratory flow is directed to the inspiratory lumen, or to the endotracheal tube, or at once to the inspiratory lumen and to the endotracheal tube.

Abstract: A device and method for controlling a level of ventilatory assist applied to a patient by a mechanical ventilator measures, during patient's assisted breath, an inspiratory volume Vassist produced by both the patient and the mechanical ventilator, an inspiratory volume Vvent contributed by the mechanical ventilator, and an inspiratory assist pressure Pvent produced by the mechanical ventilator. A first relation between pressure Pvent and volume Vassist and a second relation between pressure Pvent and volume Vvent are calculated. Using the first and second relations, a ratio is determined between pressure Pvent at volume Vvent and pressure Pvent at volume Vassist, with volume Vvent equal to volume Vassist, for a plurality of volumes Vvent and Vassist. Values of Pvent are multiplied by the corresponding calculated ratios to calculate a third relation between a predicted inspiratory pressure Ppred and volume Vassist.

Abstract: The present disclosure relates to a method and a mechanical ventilation system for adjusting a level of ventilatory assist to a patient. A neuro-mechanical efficiency of the patient is determined. A control value is received at the mechanical ventilation system. The level of ventilatory assist to the patient is determined on the basis of the neuro-mechanical efficiency and of the control value. The mechanical ventilation system may be adjusted automatically based on the determined level of ventilatory assist to the patient. Alternatively, the determined level of ventilatory assist to the patient may be displayed for the benefit of an operator and a manual command may be received for adjusting the mechanical ventilation system.

Abstract: The present disclosure relates to a method and a system for validating inspiratory muscle activity of a patient. Left and right electrical activity signals respectively representing activity of a left muscle and of a right muscle synchronized with an inspiratory effort of the patient are acquired from non-invasive sensors. A cardiac activity signal is extracted from the left and right electrical activity signals. A synchrony, a symmetry or a proportionality of the left and right electrical activity signals from which the cardiac activity signal is extracted is verified. A mechanical ventilation system incorporating the system for validating inspiratory muscle activity of the patient is also disclosed.

Abstract: The present disclosure relates to a method and a system for quantifying timing discrepancies between inspiratory effort and ventilatory assist. A trigger error is determined by comparing a start time of neural inspiration with a start time of the ventilatory assist. A cycling-off error is determined by comparing an end time of the neural inspiration with an end time of the ventilatory assist. The ventilatory assist is synchronized when the trigger error is lower than a first threshold and the cycling-off error is lower than a second threshold. The ventilatory assist may also be characterized in terms of early or late trigger and of early or late cycling-off. A trigger of a ventilator may be adjusted according to the trigger error and a cycling-off of a ventilator may be adjusted according to the cycling-off error.

Abstract: A device and method for controlling a level of ventilatory assist applied to a patient by a mechanical ventilator measures, during patient's assisted breath, an inspiratory volume Vassist produced by both the patient and the mechanical ventilator, an inspiratory volume Vvent contributed by the mechanical ventilator, and an inspiratory assist pressure Pvent produced by the mechanical ventilator. A first relation between pressure Pvent and volume Vassist and a second relation between pressure Pvent and volume Vvent are calculated. Using the first and second relations, a ratio is determined between pressure Pvent at volume Vvent and pressure Pvent at volume Vassist, with volume Vvent equal to volume Vassist, for a plurality of volumes Vvent and Vassist. Values of Pvent are multiplied by the corresponding calculated ratios to calculate a third relation between a predicted inspiratory pressure Ppred and volume Vassist.

Abstract: A ventilatory assist system and method are disclosed. The system comprises a tube for connection to a patient's airway, inspiratory and expiratory tube lumens connected to the tube, an inspiratory air source connected to the inspiration tube lumen, and a controller of air pressure in the expiratory tube lumen. The pressure controller is responsive to a physiological breathing signal representative of patient's inspiratory effort to allow air flow through the expiratory tube lumen during a patient's expiration phase, partially restricting the air flow through the expiratory tube lumen to a so minimum air flow during a patient's inspiration phase. During both respiratory phases, a unidirectional air flow is produced through the inspiratory and expiratory tube lumens to prevent air expired by the patient from being breathed again. The physiological breathing signal allows synchronization of the ventilatory assist with breathing efforts of the patient.

Abstract: The present disclosure relates to a method and a mechanical ventilation system for adjusting a level of ventilatory assist to a patient. A neuro-mechanical efficiency of the patient is determined. A control value is received at the mechanical ventilation system. The level of ventilatory assist to the patient is determined on the basis of the neuro-mechanical efficiency and of the control value. The mechanical ventilation system may be adjusted automatically based on the determined level of ventilatory assist to the patient. Alternatively, the determined level of ventilatory assist to the patient may be displayed for the benefit of an operator and a manual command may be received for adjusting the mechanical ventilation system.

Abstract: A negative pressure ventilation device comprises an inflatable tubular enclosure for surrounding a patient's torso and for defining, when inflated, a space between the tubular enclosure and the patient's torso. A sealing arrangement for the space between the tubular enclosure and the patient's torso is configured for positioning between the tubular enclosure and the patient's torso. A port is mounted to the inflatable tubular enclosure for accessing the space between the enclosure and the patient's torso to produce a negative pressure in the space. A method for negative pressure ventilation using the foregoing negative pressure ventilation device and a negative pressure ventilation system comprising the negative pressure ventilation device are also disclosed.

Abstract: The present disclosure relates to a method and a system for validating inspiratory muscle activity of a patient. Left and right electrical activity signals respectively representing activity of a left muscle and of a right muscle synchronized with an inspiratory effort of the patient are acquired from non-invasive sensors. A cardiac activity signal is extracted from the left and right electrical activity signals. A synchrony, a symmetry or a proportionality of the left and right electrical activity signals from which the cardiac activity signal is extracted is verified. A mechanical ventilation system incorporating the system for validating inspiratory muscle activity of the patient is also disclosed.

Abstract: In a method for positioning linear array of electrodes (LAE) mounted on distal end section of elongated flexible member in patient's respiratory airways (PRA) at level of diaphragm, a length of the member pre-determined to position LEA at the level of the diaphragm is inserted through PRA. Signals representative of an electrical activity of the diaphragm (EAdi) are detected through LAE, presence/absence of ECG signal components is detected in EAdi signals, and position of LAE in PRA is detected in response to presence/absence of ECG signal components in EAdi signals. Lower esophageal sphincter activity may be detected in EAdi signals, and position of LAE in PRA determined in response to the detected lower esophageal sphincter. End-expiratory occlusion of PRA may be performed to verify that the electrical activity of the diaphragm coincides with a negative deflection of PRA pressure again in view of determining adequate positioning of LAE.

Abstract: A device for providing ventilatory assist to a patient is disclosed. The device comprises a manifold having an inspiratory port to receive an inspiratory flow from an inspiratory supply line, an interface port connectable to an external end of an endotracheal tube inserted in a patient's trachea and an expiratory port configured to receive an expiratory flow from the endotracheal tube via the interface port. An inspiratory lumen has a distal end insertable in the endotracheal tube. A cross-section of the inspiratory lumen is smaller than that of the endotracheal tube to allow gas flowing in the endotracheal tube. The inspiratory flow is directed to the inspiratory lumen, or to the endotracheal tube, or at once to the inspiratory lumen and to the endotracheal tube. A ventilatory assist system and method using the device are also disclosed.

Abstract: A method and device for determining dynamic hyperinflation during mechanical ventilation of a spontaneously breathing patient, wherein mechanical ventilation is removed during one breath of the patient, inspiratory and expiratory volumes of the patient are measured during the one breath, and a difference between the inspiratory and expiratory volumes measured during the one breath is calculated. Dynamic hyperinflation of the patient's lungs is indicated in relation to the calculated difference.

Abstract: A method and system for measuring changes in inspiratory load of a patient's respiratory system during mechanical ventilation. The method and system calculate a first relation between a measured inspiratory airway pressure and a measured electrical activity of respiratory muscle, and a second relation between a measured inspiratory volume and the measured electrical activity. A load index is calculated from the first and second relations. Changes in inspiratory load are determined based on the load index.

Abstract: A method and device determine a level of mechanical ventilatory assist to be delivered to a patient. A patient's neural respiratory drive is measured and multiplied by an existing amplification factor to obtain an existing predicted ventilatory pressure. A mechanical ventilator is controlled accordingly. An existing resulting pressure is measured. The patient's neural respiratory drive is multiplied by a modified amplification factor to obtain a new predicted pressure. The existing and new predicted pressures are compared to determine an anticipated change in pressure. The mechanical ventilator is now controlled according to the new predicted pressure. A new resulting pressure is measured. The existing and new resulting pressures are compared to determine an actual change in pressure. The anticipated and actual changes in pressure are compared. The amplification factor is increased, maintained or decreased in response to the comparison between the anticipated and actual changes in pressure.

Abstract: A ventilatory assist system and method are disclosed. The system comprises a tube for connection to a patient's airway, inspiratory and expiratory tube lumens connected to the tube, an inspiratory air source connected to the inspiration tube lumen, and a controller of air pressure in the expiratory tube lumen. The pressure controller is responsive to a physiological breathing signal representative of patient's inspiratory effort to allow air flow through the expiratory tube lumen during a patient's expiration phase, partially restricting the air flow through the expiratory tube lumen to a so minimum air flow during a patient's inspiration phase. During both respiratory phases, a unidirectional air flow is produced through the inspiratory and expiratory tube lumens to prevent air expired by the patient from being breathed again. The physiological breathing signal allows synchronization of the ventilatory assist with breathing efforts of the patient.

Abstract: The present disclosure relates to a method and a system for quantifying timing discrepancies between inspiratory effort and ventilatory assist. A trigger error is determined by comparing a start time of neural inspiration with a start time of the ventilatory assist. A cycling-off error is determined by comparing an end time of the neural inspiration with an end time of the ventilatory assist. The ventilatory assist is synchronized when the trigger error is lower than a first threshold and the cycling-off error is lower than a second threshold. The ventilatory assist may also be characterized in terms of early or late trigger and of early or late cycling-off. A trigger of a ventilator may be adjusted according to the trigger error and a cycling-off of a ventilator may be adjusted according to the cycling-off error.

Abstract: The present invention relates to a system and method for determining a patient-ventilator breath contribution index in a spontaneously breathing, mechanically ventilated patient. A patient's efficiency to generate an inspiratory volume without mechanical ventilatory assist and a patient's efficiency to generate an inspiratory volume with mechanical ventilatory assist are calculated and used to determine the patient-ventilator breath contribution index.