There is provided a system for monitoring transpulmonary pressure of a mechanically ventilated individual, comprising: a feeding tube, at least one esophageal body, a pressure sensor, and a memory having stored thereon code for: computing an estimate of esophageal wall pressure according to pressure in the esophageal body when inflated and contacting the inner wall of the esophagus, computing the transpulmonary pressure of the mechanically ventilated target individual according to the esophageal wall pressure, periodically inflating and deflating the esophageal body for periodic monitoring of the transpulmonary pressure of the mechanically ventilated target patient while the feeding tube is in use, and computing instructions for adjustment of parameter(s) of a mechanical ventilator that automatically ventilates the target individual according to the computed transpulmonary pressure, wherein the instructions for adjustment of parameter(s) of the mechanical ventilator are computed while the feeding tube is in place without removal of the feeding tube.

There is provided a system for monitoring transpulmonary pressure of a mechanically ventilated individual, comprising: a feeding tube, at least one esophageal body, a pressure sensor, and a memory having stored thereon code for: computing an estimate of esophageal wall pressure according to pressure in the esophageal body when inflated and contacting the inner wall of the esophagus, computing the transpulmonary pressure of the mechanically ventilated target individual according to the esophageal wall pressure, periodically inflating and deflating the esophageal body for periodic monitoring of the transpulmonary pressure of the mechanically ventilated target patient while the feeding tube is in use, and computing instructions for adjustment of parameter(s) of a mechanical ventilator that automatically ventilates the target individual according to the computed transpulmonary pressure, wherein the instructions for adjustment of parameter(s) of the mechanical ventilator are computed while the feeding tube is in place without removal of the feeding tube.

The invention relates to methods and systems for determining the intention of a subject to perform a voluntary action based on the analysis of the subject's respiratory phases and neuroelectrical signals.

In a respiratory apparatus for treatment of sleep apnea and other disorders associated with an obstruction of a patient's airway and which uses an airflow signal, an obstruction index is generated which detects the flattening of the inspiratory portion of the airflow. The obstruction index is used to differentiate normal and obstructed breathing. The obstruction index is based upon different weighting factors applied to sections of the airflow signal thereby improving sensitivity to various types of respiration obstructions.

In a respiratory apparatus for treatment of sleep apnea and other disorders associated with an obstruction of a patient's airway and which uses an airflow signal, an obstruction index is generated which detects the flattening of the inspiratory portion of the airflow. The obstruction index is used to differentiate normal and obstructed breathing. The obstruction index is based upon different weighting factors applied to sections of the airflow signal thereby improving sensitivity to various types of respiration obstructions.

A medical ventilator (10) performs a method including: receiving measurements of pressure of air inspired by or expired from a ventilated patient (12) operatively connected with the medical ventilator; receiving measurements of air flow into or out of the ventilated patient operatively connected with the medical ventilator; dividing a breath time interval into a plurality of fitting regions (60); and simultaneously estimating respiratory system's resistance and compliance or elastance, and respiratory muscle pressure in each fitting region by fitting to a time series of pressure and air flow samples in that fitting region. In one approach, the fitting includes parameterizing the respiratory muscle pressure by a continuous differentiable function, such as a polynomial function, over the fitting region. In another approach, the fitting is to an equation of motion of the lungs in each fitting region, while monotonicity constraints and inequalities bounding at least the respiratory muscle pressure P.sub.mus(t) and respiratory system's resistence R and compliance C are applied to the respiratory muscle pressure in each region.

A medical ventilator (10) performs a method including: receiving measurements of pressure of air inspired by or expired from a ventilated patient (12) operatively connected with the medical ventilator; receiving measurements of air flow into or out of the ventilated patient operatively connected with the medical ventilator; dividing a breath time interval into a plurality of fitting regions (60); and simultaneously estimating respiratory system's resistance and compliance or elastance, and respiratory muscle pressure in each fitting region by fitting to a time series of pressure and air flow samples in that fitting region. In one approach, the fitting includes parameterizing the respiratory muscle pressure by a continuous differentiable function, such as a polynomial function, over the fitting region. In another approach, the fitting is to an equation of motion of the lungs in each fitting region, while monotonicity constraints and inequalities bounding at least the respiratory muscle pressure P.sub.mus(t) and respiratory system's resistence R and compliance C are applied to the respiratory muscle pressure in each region.

The invention relates to providing novel functions to the coaxial breathing circuits which at present do not comprise water traps, by adding a closed system water trap designed to have an inkwell shape and a lung pressure measurement port to said circuits wherein the fluid collected in the bottle section can be discharged without having to open the bottle by means of a drainage luer port located at the base of the bottle and a needleless apparatus that has been inserted into the port, and an injector.

A measurement unit for measuring a bio-impedance of a body, the measurement unit comprising a current generator circuit, a readout circuit, and a baseline cancellation current circuit, wherein the current generator circuit is configured to amplify a reference current to form a measurement current to be driven through a body to generate a measurement voltage representing the bio-impedance; wherein the readout circuit comprises a Instrumentation amplifier (IA) which has a transconductance stage and a transimpedance stage, wherein the IA is configured to: produce a first current in the transconductance stage, the first current being proportional to the measurement voltage, receive a second current from the baseline cancellation current circuit, produce an output voltage in the transimpedance stage, the output voltage being proportional to a difference between the first current and the second current and representative of the measured bio-impedance; wherein the baseline cancellation current circuit is configured to amplify the reference current by a factor to form the second current and deliver it to the IA, wherein the factor is such that that the absolute value of the difference between the first and the second current is below a threshold such that a baseline of the first current is cancelled by the second current.

In one aspect, a computer-implemented method includes receiving a signal corresponding to impedance across a patient's chest cavity; filtering the signal using one or more filters that reduce noise and center the signal around a zero baseline; adjusting an amplitude of the filtered signal based on a threshold value; separating the amplitude-adjusted signal into component signals, where each of the component signals represents a frequency-limited band; detecting a fractional phase transition of a component signal of the component signals; selecting a dominant component signal from the component signals based on amplitudes of the component signals at a time corresponding to the detected fractional phase transition; determining a frequency of the dominant component signal at the time corresponding to the detected fractional phase transition; and determining a respiratory rate of the patient based on the determined frequency.