This disclosure describes systems and methods for controlling pressure and/or flow during exhalation. The disclosure describes novel exhalation modes for ventilating a patient.

A system selectively delivers either breath-synchronized, flow-targeted ventilation (BSFTV) or closed-system positive pressure ventilation (CSPPV) to augment respiration of a patient with a standard tracheal tube. A removable adaptor has a cap that can be removably attached to the proximal connector of the tracheal tube in BSFTV mode, and an inner cannula that extends within the tracheal tube to effectively divide it into two lumens. The adaptor includes a ventilator connector for removably engaging a ventilator hose to deliver air/oxygen through the adaptor and one lumen of the tracheal tube with a flow rate varying over each respiratory cycle in a predetermined waveform synchronized with the patient's respiratory cycle to augment the patient's spontaneous respiration. The adaptor also includes a port allowing the spontaneously-breathing patient to freely inhale and exhale in open exchange with the atmosphere through the other lumen.

A system selectively delivers either breath-synchronized, flow-targeted ventilation (BSFTV) or closed-system positive pressure ventilation (CSPPV) to augment respiration of a patient with a standard tracheal tube. A removable adaptor has a cap that can be removably attached to the proximal connector of the tracheal tube in BSFTV mode, and an inner cannula that extends within the tracheal tube to effectively divide it into two lumens. The adaptor includes a ventilator connector for removably engaging a ventilator hose to deliver air/oxygen through the adaptor and one lumen of the tracheal tube with a flow rate varying over each respiratory cycle in a predetermined waveform synchronized with the patient's respiratory cycle to augment the patient's spontaneous respiration. The adaptor also includes a port allowing the spontaneously-breathing patient to freely inhale and exhale in open exchange with the atmosphere through the other lumen.

Liquid ventilator and methods integrating the concept of total liquid ventilation (TLV) using liquid volumes below functional residual capacity (FRC) of mammal's lungs are disclosed. Beyond the automatization of the whole process, the technology has been up-scaled to confirm that TLV at residual volumes below FRC can provide a safe procedure while enabling the full potential of TLV in a mammal such as humans or adult-sized animals. Such tidal liquid ventilation strongly differs from the previously known TLV approach, opening promising perspectives for a safer clinical translation. Also disclosed are apparatus and method for safe and fast induction of hypothermia during liquid ventilation of a mammal.

An apparatus and method for assessing vascular compliance in subjects with multiple sclerosis using sequential gas delivery is provided. The apparatus includes a gas delivery device and a processor. The processor controls the gas delivery device to deliver a first and second gas during a single inspiration. The first gas contains a mixture of oxygen and carbon dioxide necessary to target an end-tidal concentration of the two gases. The second gas includes a concentration of carbon dioxide equal to the target end-tidal concentration of carbon dioxide.

An apparatus and method for assessing vascular compliance in subjects with multiple sclerosis using sequential gas delivery is provided. The apparatus includes a gas delivery device and a processor. The processor controls the gas delivery device to deliver a first and second gas during a single inspiration. The first gas contains a mixture of oxygen and carbon dioxide necessary to target an end-tidal concentration of the two gases. The second gas includes a concentration of carbon dioxide equal to the target end-tidal concentration of carbon dioxide.

To provide a prediction display system and the like that utilize information obtained before an operation and during the operation, and predict an onset risk of a postoperative complication such as an acute kidney injury which has become a particularly great clinical problem. A prediction display system is configured such that an onset risk of a complication occurring after an operation is predicted using at least one of pH (hydrogen ion exponent), pO2 (oxygen partial pressure), Ht (hematocrit value), Hb (hemoglobin), DO2 (transportation amount of oxygen), and pCO2 (arterial blood carbon dioxide partial pressure) as parameters of blood gas taken before the operation and during the operation, and the onset risk of the complication occurring after the operation is displayed.

A gas humidifier can have a gas channel comprising an inlet and an outlet. A portion of the gas channel can have a region having a reduction in cross-sectional area relative to the portions of the gas channel outside of the region. A water conduit can extend from the region to a water reservoir. A heating element can heat water entering the region from the water conduit. Water vaporized using the heating element can join the flow of gases passing through the gas channel in use.

A breath analyzer for detecting breathing events of a person ventilated with a respiratory gas, comprising an electronic computing and storage unit configured to receive a signal corresponding to a ventilation pressure and/or a respiratory flow and/or a tidal volume of the respiratory gas delivered to the person and, during a predetermined analysis duration, to detect a curve of the signal by a curve analyzer. A ventilator for ventilating a person with a respiratory gas, which ventilator comprises the breath analyzer and a method for detecting breathing events of a person ventilated with a respiratory gas is also described.

An automatic ventilator adjusting system has a three-way inline adapter coupled to 1) a breath sample line, 2) a ventilator (either invasive or non-invasive), and 3) a patient. The breath sample line is coupled to a Gas Exchange Monitor (GEM) and preferably has a female Luer lock end. Ventilator settings can be automatically set and/or adjusted using 1) an algorithm preferably having a feedback loop and 2) inputs including one or more of: gPaO.sub.2 (calculated arterial partial pressure of O.sub.2 by GEM), oxygen deficit, gPaCO.sub.2 (calculated arterial partial pressure of CO.sub.2), gPaCO.sub.2/gPaO.sub.2, PiO.sub.2-PETO.sub.2, TLC (Total Lung Capacity), FRC (Functional Residual Capacity), and Vd/Vt (deadspace ratio). Preferably, one or more of the inputs (e.g., gPaO.sub.2 gPaCO.sub.2, and oxygen deficit) are obtained non-invasively from a patient's normal breathing gas samples as calculated by MediPines Gas Exchange Monitor (GEM).