System and method for estimation and control of compliance and pressure/volume variations within a body cavity

A bio-liquid replacement system for controlled infusion, effusion, and/or perfusion of a biological liquid or a biocompatible liquid to and from a body cavity of a subject, comprising:

• at least one sensor for continuously measuring at least one parameter associated with the body cavity,
• a pump unit for infusing the biological liquid or the biocompatible liquid into the body cavity and aspirating the biological liquid or the biocompatible liquid out of the body cavity,
• a processing unit configured for continuously 1) calculating at least one physiological parameter based on the at least one measured parameter, and 2) defining at least one target parameter, such that the at least one target parameter is slightly offset from the at least one physiological parameter in a time varying manner, and
• a flow controller configured for controlling said pump unit based on said at least one target parameter such that continuous compensatory changes are induced in a liquid volume in the body cavity,
• wherein the processing unit is configured for continuously estimating a compliance within the body cavity based on said at least one physiological parameter;
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• wherein the estimation of the compliance is filtered in accordance with
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A method for estimating compliance within a body cavity of a subject based on controlled infusion, effusion, and/or perfusion of a biological liquid or a biocompatible liquid to and from the body cavity, the method comprising the steps of:

• continuously obtaining at least one physiological parameter associated with the body cavity,
• continuously defining at least one target parameter associated with the body cavity, such that the at least one target parameter is slightly offset from the at least one physiological parameter, in a time varying manner, such that continuous compensatory changes are induced in a liquid volume in the body cavity, and
• continuously estimating the compliance within the body cavity based on said at least one physiological parameter;
• wherein the compliance is estimated as
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• where Δ{dot over (v)}(k)={dot over (v)}infusion(k)−{dot over (v)}aspiration(k) is a net perfusion flow rate at time k in a time interval [t, ts(t)], ƒp(t) is a value of a function, ƒ, of a measured pressure, p, at time t, ƒp(ts(t)) is a value of the function, ƒ, of the measured pressure, p, at time ts(t).

A compliance estimator system for estimating compliance within a body cavity, comprising:

• a communication unit for receiving data corresponding to at least one measured parameter related to the body cavity and for communicating with a flow controller, and
• a processor configured for:
• a) calculating at least one physiological parameter based on the at least one measured parameter,
• b) defining at least one target parameter, such that the at least one target parameter is slightly offset from the at least one physiological parameter in a time varying manner, and
• c) forwarding a control signal, based on the at least one target parameter, to the flow controller, such that continuous compensatory changes are induced in a liquid volume in the body cavity,
• d) repeating steps a)-c)
• wherein the compliance within the body cavity is continuously estimated based on said at least one physiological parameter;
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• wherein the compliance is estimated as
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