A system for estimating maximum heart rate and maximal oxygen uptake from submaximal exercise intensities can include an exercise intensity monitor, a cardiopulmonary monitor, and one or more computers. The computers can be configured, by virtue of appropriate programming, to receive submaximal exercise intensity data from the exercise intensity monitor and submaximal cardiopulmonary data from the cardiopulmonary monitor while a user, who coupled to the exercise intensity monitor and the cardiopulmonary monitor, is performing an exercise at a submaximal exercise intensity. The one or more computers then determine a heuristic estimate of a maximal cardiopulmonary state of the user based on the submaximal exercise intensity data and the submaximal cardiopulmonary data.

Systems and methods for evaluating patients are provided. An example includes receiving first cardiopulmonary exercise test data for the patient and plotting a first vector based on the first cardiopulmonary exercise test data, the first vector including a first point based on a rest value and a second point based on an exercise value. A first coordinate value of the first point and a first coordinate value of the second point may be based on mixed expired CO.sub.2 (PECO.sub.2) and a second coordinate value of the first point and a second coordinate value of the second point may be based on end tidal CO.sub.2 (PetCO.sub.2). The example may also include plotting a midpoint of the first vector and triggering display of the plotted vector and plotted midpoint. The plotted vector and plotted midpoint may be displayed over a coordinate grid having multiple physiological condition zones.

Systems and methods for evaluating patients are provided. An example includes receiving first cardiopulmonary exercise test data for the patient and plotting a first vector based on the first cardiopulmonary exercise test data, the first vector including a first point based on a rest value and a second point based on an exercise value. A first coordinate value of the first point and a first coordinate value of the second point may be based on mixed expired CO.sub.2 (PECO.sub.2) and a second coordinate value of the first point and a second coordinate value of the second point may be based on end tidal CO.sub.2 (PetCO.sub.2). The example may also include plotting a midpoint of the first vector and triggering display of the plotted vector and plotted midpoint. The plotted vector and plotted midpoint may be displayed over a coordinate grid having multiple physiological condition zones.

Active auscultation may be used to determine organ (e.g., lung or heart) characteristics of users. An acoustic or piezo-electric signal (e.g., a pulse, a tone, and/or a broadband pulse) may be projected into an animal (typically human) body or thorax. The signal interacts with the body, or lungs, and in some cases may induce resonance within the body/lungs. A resultant signal may be emitted from the body which may be analyzed to determine, for example, a lung's resonant frequency or frequencies and/or how the sound is otherwise absorbed, reflected, or modified by the body. This information may be indicative of lung characteristics such as lung capacity, a volume of air trapped in the lungs, and/or the presence of COPD.

Active auscultation may be used to determine organ (e.g., lung or heart) characteristics of users. An acoustic or piezo-electric signal (e.g., a pulse, a tone, and/or a broadband pulse) may be projected into an animal (typically human) body or thorax. The signal interacts with the body, or lungs, and in some cases may induce resonance within the body/lungs. A resultant signal may be emitted from the body which may be analyzed to determine, for example, a lung's resonant frequency or frequencies and/or how the sound is otherwise absorbed, reflected, or modified by the body. This information may be indicative of lung characteristics such as lung capacity, a volume of air trapped in the lungs, and/or the presence of COPD.

Described is an apparatus for oxygenation and/or CO2 clearance of a patient, comprising: a flow source or a connection for a flow source for providing a gas flow, a gas flow modulator, a controller to control the gas flow, wherein the controller is operable to: receive input relating to heart activity and/or trachea gas flow of the patient, and control the gas flow modulator to provide a varying gas flow with one or more oscillating components with a frequency or frequencies based on the heart activity and/or trachea flow of the patient.

Described is an apparatus for oxygenation and/or CO2 clearance of a patient, comprising: a flow source or a connection for a flow source for providing a gas flow, a gas flow modulator, a controller to control the gas flow, wherein the controller is operable to: receive input relating to heart activity and/or trachea gas flow of the patient, and control the gas flow modulator to provide a varying gas flow with one or more oscillating components with a frequency or frequencies based on the heart activity and/or trachea flow of the patient.

Systems and methods for detecting worsening cardiac conditions such as worsening heart failure events are described. A system may include sensor circuits to sense physiological signals and signal processors to generate from the physiological signals first and second signal metrics. The system may include a risk stratifier circuit to produce a cardiac risk indication. The system may use at least the first signal metric to generate a primary detection indication, and use at least the second signal metric and the risk indication to generate a secondary detection indication. The risk indication may be used to modulate the second signal metric. A detector circuit may detect the worsening cardiac event using the primary and secondary detection indications.

Systems and methods for detecting worsening cardiac conditions such as worsening heart failure events are described. A system may include sensor circuits to sense physiological signals and signal processors to generate from the physiological signals first and second signal metrics. The system may include a risk stratifier circuit to produce a cardiac risk indication. The system may use at least the first signal metric to generate a primary detection indication, and use at least the second signal metric and the risk indication to generate a secondary detection indication. The risk indication may be used to modulate the second signal metric. A detector circuit may detect the worsening cardiac event using the primary and secondary detection indications.

A pulmonary neuromuscular metrics device that allows the measurement of pulmonary neuromuscular metrics, that is, breathing power, force, and work (that is, energy expended), in patients with neuromuscular conditions. The device may be used in the medical office or remotely at a patient's house, thereby allowing the patient to be followed medically without the need for more frequent and repeated office visits.