Monitoring total circulating blood volume and cardiac output

The method for determining hemodynamic parameter of a cardiovascular system wherein blood within a bloodstream is circulated to peripheral regions of the body, comprising the steps of.

• (a) providing a source of analyte-containing fluid biocompatible with and metabolizable within said body and having a predetermined analyte concentration;
• (b) providing fluid flow control apparatus having an input coupled in fluid flow communication with said source of analyte-containing fluid and actuable to provide a flow of said analyte-containing fluid at a mass flow rate at an outlet for an infusion interval;
• (c) providing an analyte concentration sensor having a distal analyte responsive portion and a communication channel extending therefrom to a proximal region, and being controllable from said proximal region to provide sensor outputs corresponding with the sensed concentration of said analyte;
• (d) providing a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow and an output positionable within said bloodstream through which said analyte containing fluid is expressible at said mass flow rate;
• (e) providing a controller operatively responsive with said fluid flow control apparatus and coupled in controlling relationship with said analyte concentration sensor, and actuable to record the time of delivery of said analyte-containing fluid at the commencement of said infusion interval, responsive thereafter to control said analyte concentration sensor to effect provision of timed sequence of said sensor outputs and derive a corresponding sequence of time associated analyte concentration values, said time associated sequence of analyte concentration values rising in value toward a peak value and decreasing in value therefrom, responsive to correlate said time associated sequence of analyte concentration values, said mass flow rate and said time of delivery to derive an output signal representing a value corresponding with a select hemodynamic parameter;
• (f) positioning said analyte concentration sensor distal analyte responsive portion and said delivery assembly output within said bloodstream at a said peripheral region:
• (g) actuating said controller to derive said output signal;
• and
• (h) providing a readout responsive to said output signal and having a perceptible output identifying the value of the hemodynamic parameter corresponding therewith.

The method for determining the total circulating blood volume of a cardiovascular system circulating blood within a bloodstream extending to a peripheral region of a body and exhibiting a pH value, comprising the steps of:

• (a) providing a source of analyte-containing fluid biocompatible with and metabolizable within said body and having a predetermined analyte concentration;
• (b) providing an analyte concentration sensor having a distal analyte responsive portion configured for positioning within said bloodstream and responsive to the presence of said analyte to provide sensor outputs corresponding with the sensed concentration of analyte;
• (c) providing a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said source of analyte containing fluid and an output configured for positioning within said bloodstream;
• (d) positioning said analyte concentration sensor distal analyte responsive portion and said delivery assembly output within said bloodstream;
• (e) delivering said analyte-containing fluid from said source into said delivery channel at a time of delivery, and at a dose value defining mass flow rate, at said predetermined analyte concentration, and over an infusion interval;
• (f) deriving a sequence of time associated analyte concentration values from said sensor outputs;
• (g) monitoring said sequence of time associated concentration values and identifying a sequence thereof descending in value from a peak-defining inflection value;
• and
• (h) deriving a value for total circulating blood volume by correlating said time of delivery, said dose value and identified sequence of time associated concentration values descending in value.

The method for determining hemodynamic parameters of a cardiovascular system wherein blood within a bloodstream is circulated to peripheral regions of the body and exhibits a pH value, comprising the steps of:

• (a) providing a source of analyte-containing fluid biocompatible with and metabolizable within said body and having a predetermined analyte concentration;
• (b) providing an analyte concentration sensor having a distal analyte responsive portion configured for positioning within said bloodstream and responsive to the presence of analyte to provide sensor outputs corresponding with the sensed concentration of analyte;
• (c) providing a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said source of analyte-containing fluid and an output configured for positioning within the bloodstream;
• (d) positioning said analyte concentration sensor distal analyte responsive portion and said delivery assembly output within said bloodstream;
• (e) delivering said analyte-containing fluid from said source into said delivery channel at a time of delivery, a mass flow rate and over an infusion interval;
• (f) deriving a sequence of time associated analyte concentration values from said sensor outputs;
• (g) monitoring said sequence of time associated analyte concentration values and identifying a sequence thereof rising in value to a peak defining inflection value and descending in value therefrom;
• and
• (h) deriving a value for a select one of said hemodynamic parameters by correlating said sequence of time associated concentration values, said mass flow rate, said infusion interval and said predetermined analyte concentration.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• a blood by-passing assembly including:
• a blood transport conduit extending from a proximal end to a distal tip, said distal tip being positionable in blood exchange relationship within said bloodstream
• a blood sampling chamber coupled in blood exchange communication with said blood transport conduit proximal end, and
• a pump coupled with said sampling chamber and controllable to urge the transport of blood from said bloodstream into said sampling chamber;
• an analyte concentration sensor positioned within said blood sampling chamber, responsive to analyte within said blood and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• and
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said pump and analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• and
• a readout responsive to said output signal for providing a perceptible output corresponding therewith.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• said controller is responsive to control said analyte concentration sensor prior to said provision of said flow of analyte-containing fluid to provide said sensor outputs and derive a corresponding baseline value for concentration of said analyte, and is responsive to correlate said baseline value for concentration of said analyte with said time associated concentration values, said predetermined mass flow-rate, said predetermined analyte concentration and said infusion interval to derive said output signal;
• said select hemodynamic parameter is cardiac output;
• said controller is responsive to correlate said baseline value for concentration of said analyte, said predetermined mass flow rate said predetermined analyte concentration and said peak value of said time associated concentration values to derive said output signal as corresponding with cardiac output;
• and
• a readout responsive to said output signal for providing a perceptible output corresponding therewith.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• said controller is responsive to control said analyte concentration sensor prior to said provision of said flow of analyte-containing fluid to provide said sensor outputs and derive a corresponding baseline value for concentration of said analyte, and is responsive to correlate said baseline value for concentration of said analyte with said time associated concentration values, said predetermined mass flow-rate said predetermined analyte concentration and said infusion interval to derive said output signal;
• said select hemodynamic parameter is cardiac output;
• said controller is responsive to correlate said baseline value for concentration of said analyte, said predetermined mass flow rate, said predetermined analyte concentration, said infusion interval, and an integrated value of said time associated concentration values to derive said output signal as corresponding with cardiac output;
• and
• a readout responsive to said output signal for providing a perceptible output corresponding therewith.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• said select hemodynamic parameter is total circulating blood volume;
• said controller is responsive to correlate said predetermined analyte concentration, said predetermined mass flow rate and said infusion interval to derive a dose value, and is responsive to derive a maximum increase value for said analyte within said bloodstream by correlating said time associated concentration values descending in value with said time of delivery, and is responsive to said dose value and to said maximum increase value to derive said output signal as corresponding with total circulating blood volume;
• and
• a readout responsive to said output signal for providing a perceptible output corresponding therewith.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• a readout responsive to said output signal for providing a perceptible output corresponding therewith;
• said select hemodynamic parameter is total circulating blood volume;
• said controller includes an inputting assembly manually controllable to provide a total circulating blood volume threshold value;
• said controller is responsive to said total circulating blood volume threshold value to retain it in memory;
• said controller is responsive in the presence of a given output signal corresponding with a given value for total circulating blood volume and to said memory retained total circulating blood volume threshold value to derive an alarm signal when said given value for total circulating blood volume is greater than or equal to said total circulating blood volume threshold value;
• and
• said readout is responsive to said alarm signal to provide a perceptible alarm output.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• a readout responsive to said output signal for providing a perceptible output corresponding therewith;
• said select hemodynamic parameter is total circulating blood volume;
• said controller includes an inputting assembly manually controllable to provide a total circulating blood volume threshold value;
• said controller is responsive in the presence of a given output signal corresponding with a given value for total circulating blood volume and for said memory retained total circulating blood volume threshold value to derive an alarm signal when said given value for total circulating blood volume is less than or equal to said total circulating blood volume threshold value;
• and
• said readout is responsive to said alarm signal to provide a perceptible alarm output.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• a readout responsive to said output signal for providing a perceptible output corresponding therewith;
• said select hemodynamic parameter is total circulating blood volume;
• said controller includes an inputting assembly manually controllable to provide a rate of change of total circulating blood volume threshold value;
• said controller is responsive to said rate of change of total circulating blood volume threshold value to retain it in memory;
• said controller is responsive in the presence of a given output signal corresponding with a given value for total circulating blood volume and to a previous such value for total circulating blood volume to derive a current total circulating blood volume rate of change value, and is responsive to said rate of change of total circulating blood value threshold value and to said current total circulating blood volume rate of change value to derive an alarm signal when said current total circulating blood volume rate of change value is greater than or equal to said rate of change of total circulating blood volume threshold value;
• and;
• said readout is responsive to said alarm signal to provide a perceptible alarm output.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• a readout responsive to said output signal for providing a perceptible output corresponding therewith;
• said select hemodynamic parameter is total circulating blood volume;
• said controller includes an inputting assembly manually controllable to provide a rate change of total circulating blood volume threshold value;
• said controller is responsive to said rate of change of total circulating blood volume threshold value to retain it in memory;
• said controller is responsive in the presence of a given output signal corresponding with a given value for total circulating blood volume and to a previous such value for total circulating blood volume to derive a current total circulating blood volume rate of change value, and is responsive to said rate of change of total circulating blood value threshold value and to said current total circulating blood volume rate of change value to derive an alarm signal when said current total circulating blood volume rate of change value is greater than or equal to said rate of change of total circulating blood volume threshold value;
• and;
• said readout is responsive to said alarm signal to provide a perceptible alarm output.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• a readout responsive to said output signal for providing a perceptible output corresponding therewith;
• said select hemodynamic parameter is total circulating blood volume;
• said controller is responsive in the presence of a current output signal corresponding with a current value for total circulating blood volume and is responsive to a previous value for total circulating blood volume corresponding with a previous output signal to derive a warning signal when said previous value is greater than said current value;
• and
• said readout is responsive to said alarm signal to provide a perceptible alarm output.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analytic concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• a readout responsive to said output signal for providing a perceptible output corresponding therewith;
• said select hemodynamic parameter is total circulating blood volume;
• said controller is responsive in the presence of a current output signal corresponding with a current value for total circulating blood volume and is responsive to a previous value for total circulating blood volume corresponding with a previous output signal to derive a warning signal when said previous value is less than said current value;
• and
• said readout is responsive to said alarm signal to provide a perceptible alarm output.

A system for determining hemodynamic parameters of a cardiovascular system said cardiovascular system circulating blood within a bloodstream extending to peripheral regions of a body comprising:

• a source of analyte-containing fluid biocompatible with and metabolizable within said body and said fluid having a predetermined analyte concentration;
• fluid flow control apparatus coupled with said source of analyte containing fluid and controllable to provide a flow of said analyte containing fluid at a predetermined mass flow rate at an outlet for an infusion interval having a time of delivery;
• a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said fluid flow control apparatus and an output positioned to express said flow of analyte-containing fluid within said bloodstream for dilutional movement therewith;
• an analyte concentration sensor positioned within said bloodstream, responsive to analyte within said bloodstream and controllable to provide sensor outputs corresponding with the sensed concentration of said analyte;
• a controller coupled in controlling relationship with said fluid flow control apparatus and said analyte concentration sensor, responsive to control said analyte concentration sensor to provide said sensor outputs and to derive corresponding analyte concentration values, responsive to control said fluid flow control apparatus to effect provision of said flow of said analyte-containing fluid at said outlet for said infusion interval, responsive to a sequence of said analyte concentration values, as time associated analyte concentration values, said sequence exhibiting time associated concentration values rising in value toward a peak value and descending in value, therefrom, responsive to correlate said time associated concentration values, said predetermined mass flow rate, said predetermined analyte concentration and said infusion interval to derive an output signal representing a value corresponding with a select said hemodynamic parameter;
• a readout responsive to said output signal for providing a perceptible output corresponding therewith;
• said system including:
• a blood by-passing assembly including:
• a blood transport conduit extending from a proximal end to a distal tip, said distal tip being positionable in blood exchange relationship within said bloodstream;
• a blood sampling chamber coupled in blood exchange communication with said blood transport conduit proximal end,
• a pump coupled with said sampling chamber and actuable to urge the transport of blood from said bloodstream into said sampling chamber;
• and
• said analyte concentration sensor is positioned within said bloodstream at said blood sampling chamber and is responsive to analyte within said chamber.

The method for determining hemodynamic parameters of a cardiovascular system wherein blood within a bloodstream is circulated to peripheral regions of the body and exhibits a pH value, comprising the steps of:

• (a) providing a source of analyte-containing fluid biocompatible with and metabolizable within said body and having a predetermined analyte concentration;
• (b) providing an analyte concentration sensor having a distal analyte responsive portion configured for positioning within said bloodstream and responsive to the presence of analyte to provide sensor outputs corresponding with the sensed concentration of analyte;
• (c) providing a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said source of analyte-containing fluid and an output configured for positioning within the bloodstream;
• (d) positioning said analyte concentration sensor distal analyte responsive portion and said delivery assembly output within said bloodstream;
• (e) delivering said analyte-containing fluid from said source into said delivery channel at a time of delivery, a mass flow rate and over an infusion interval;
• (f) deriving a sequence of time associated analyte concentration values from said sensor outputs;
• (g) monitoring said sequence of time associated analyte concentration values and identifying a sequence thereof rising in value to a peak defining inflection value and descending in value therefrom;
• (h) deriving a value for a select one of said hemodynamic parameters by correlating said sequence of time associated concentration values, said mass flow rate, said infusion interval and said predetermined analyte concentration;
• and
• wherein said step (h) derives a value for total circulating blood volume as said select one of said hemodynamic parameters by correlating said time of delivery, said predetermined analyte concentration, said infusion interval and identified sequence of time associated concentration values descending in value from said peak defining inflection value.

The method for determining hemodynamic parameters of a cardiovascular system wherein blood within a bloodstream is circulated to peripheral regions of the body and exhibits a pH value, comprising the steps of:

• (a) providing a source of analyte-containing fluid biocompatible with and metabolizable within said body and having a predetermined analyte concentration;
• (b) providing an analyte concentration sensor having a distal analyte responsive portion configured for positioning within said bloodstream and responsive to the presence of analyte to provide sensor outputs corresponding with the sensed concentration of analyte;
• (c) providing a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said source of analyte-containing fluid and an output configured for positioning within the bloodstream;
• (d) positioning said analyte concentration sensor distal analyte responsive portion and said delivery assembly output within said bloodstream;
• (e) delivering said analyte-containing fluid from said source into said delivery channel at a time of delivery, a mass flow rate and over an infusion interval;
• (f) deriving a sequence of time associated analyte concentration values from said sensor outputs;
• (g) monitoring said sequence of time associated analyte concentration values and identifying a sequence thereof rising in value to a peak defining inflection value and descending in value therefrom;
• (h) deriving a value for a select one of said hemodynamic parameters by correlating said sequence of time associated concentration values, said mass flow rate, said infusion interval and said predetermined analyte concentration;
• and
• wherein:
• said step (d) includes the step of:
• (d1) prior to said step (e) deriving from said analyte concentration sensor outputs a baseline value corresponding with the concentration of said analyte in said bloodstream;
• said step (h) further correlates said baseline value to derive a said select one of said hemodynamic parameters;
• and
• said step (h) derives a value for cardiac output as said select one of said hemodynamic parameters by correlating said baseline value for concentration of said analyte, said mass flow rate, said predetermined analyte concentration and said identified peak-defining inflection value.

The method for determining hemodynamic parameters of a cardiovascular system wherein blood within a bloodstream is circulated to peripheral regions of the body and exhibits a pH value, comprising the steps of:

• (a) providing a source of analyte-containing fluid biocompatible with and metabolizable within said body and having a predetermined analyte concentration;
• (b) providing an analyte concentration sensor having a distal analyte responsive portion configured for positioning within said bloodstream and responsive to the presence of analyte to provide sensor outputs corresponding with the sensed concentration of analyte;
• (c) providing a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said source of analyte-containing fluid and an output configured for positioning within the bloodstream;
• (d) positioning said analyte concentration sensor distal analyte responsive portion and said delivery assembly output within said bloodstream;
• (e) delivering said analyte-containing fluid from said source into said delivery channel at a time of delivery, a mass flow rate and over an infusion interval;
• (f) deriving a sequence of time associated analyte concentration values from said sensor outputs;
• (g) monitoring said sequence of time associated analyte concentration values and identifying a sequence thereof rising in value to a peak defining inflection value and descending in value therefrom;
• (h) deriving a value for a select one of said hemodynamic parameters by correlating said sequence of time associated concentration values, said mass flow rate, said infusion interval and said predetermined analyte concentration;
• and
• wherein:
• said step (d) includes the step of:
• (d1) prior to said step (e) deriving from said analyte concentration sensor outputs a baseline value corresponding with the concentration of said analyte in said bloodstream;
• said step (h) further correlates said baseline value to derive said select one of said hemodynamic parameters;
• and
• said step (h) derives a value for cardiac output as said select one of said hemodynamic parameters correlating said baseline value for concentration of said analyte, said mass flow rate, said predetermined analyte concentration, said infusion interval and an integrated value of said time associated concentration values.

The method for determining hemodynamic parameters of a cardiovascular system wherein blood within a bloodstream is circulated to peripheral regions of the body and exhibits a pH value, comprising the steps of:

• (a) providing a source of analyte-containing fluid biocompatible with and metabolizable within said body and having a predetermined analyte concentration;
• (b) providing an analyte concentration sensor having a distal analyte responsive portion configured for positioning within said bloodstream and responsive to the presence of analyte to provide sensor outputs corresponding with the sensed concentration of analyte;
• (c) providing a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said source of analyte-containing fluid and an output configured for positioning within the bloodstream;
• (d) positioning said analyte concentration sensor distal analytic responsive portion and said delivery assembly output within said bloodstream;
• (e) delivering said analyte-containing fluid from said source into said delivery channel at a time of delivery, a mass flow rate and over an infusion interval;
• (f) deriving a sequence of time associated analyte concentration values from said sensor outputs;
• (g) monitoring said sequence of time associated analyte concentration values and identifying a sequence thereof rising in value to a peak defining inflection value and descending in value therefrom;
• (h) deriving a value for a select one of said hemodynamic parameters by correlating said sequence of time associated concentration values, said mass flow rate, said infusion interval and said predetermined analyte concentration;
• and
• wherein:
• said step (d) is carried out by positioning said analyte concentration sensor distal analyte responsive portion and said delivery assembly output within said bloodstream at said peripheral region.

The method for determining hemodynamic parameters of a cardiovascular system wherein blood within a bloodstream is circulated to peripheral regions of the body and exhibits a pH value, comprising the steps of:

• (a) providing a source of analyte-containing fluid biocompatible with and metabolizable within said body and having a predetermined analyte concentration;
• (b) providing an analyte concentration sensor having a distal analyte responsive portion configured for positioning within said bloodstream and responsive to the presence of analyte to provide sensor outputs corresponding with the sensed concentration of analyte;
• (c) providing a delivery assembly having a delivery channel with an input coupled in fluid flow communication with said source of analyte-containing fluid and an output configured for positioning within the bloodstream;
• (d) positioning said analyte concentration sensor distal analyte responsive portion and said delivery assembly output within said bloodstream;
• (e) delivering said analyte-containing fluid from said source into said delivery channel at a time of delivery, a mass flow rate and over an infusion interval;
• (f) deriving a sequence of time associated analyte concentration values from said sensor outputs;
• (g) monitoring said sequence of time associated analyte concentration values and identifying a sequence thereof rising in value to a peak defining inflection value and descending in value therefrom;
• (h) deriving a value for a select one of said hemodynamic parameters by correlating said sequence of time associated concentration values, said mass flow rate, said infusion interval and said predetermined analyte concentration;
• and
• wherein:
• said select one of said hemodynamic parameters is total circulating blood volume;
• and
• said step (h) correlates said time of delivery and said time associated concentration values descending in value to derive a maximum increase value for said analyte within said bloodstream and correlates said maximum increase value with a dose value corresponding with said predetermined analyte concentration, said infusion interval and said mass flow rate to derive said total circulating blood volume.