Abstract: A system, and apparatus for detecting and quantifying circulatory anomalies, including right-to-left cardiac shunts. The apparatus implements a sensor system useful in connection with a circulatory indicator delivery system. The sensor apparatus is preferably configured with a series of emitter/detector pairs to optimize the sensitivity of detection of the circulating indicator. Sensing of the indicator concentration takes place at an arterial vasculature, for example, the pinna of the human ear. A monitor/controller calculates and displays a indicator/dye dilution curve to assess for the presence of a cardiac shunt. The monitor/controller further corrects the indicator/dilution curve displayed for any recirculation phenomena and can quantify any right-to-left shunt calculated conductance associated with detected shunts.

Abstract: Methods, apparatus and systems for precisely controlling a Valsalva maneuver and the timing thereof in conjunction with testing a patient for a cardiac shunt, and for ensuring that a patient performing a Valsalva maneuver creates a required pressure using their diaphragm. Embodiments of a Valsalva maneuver mouthpiece assembly are also disclosed for use with the invention methods, apparatus and systems. The mouthpiece assembly is adapted to selectively operate between a state that produces resistance to the exhalation pressure of a patient into the mouthpiece and a state wherein the pressure resistance is rapidly removed so as to cause an involuntary exhalation of the air in the patient's lungs at a time of desired Valsalva maneuver release.

Abstract: Systems and methods for detecting circulatory anomalies such as, for example, right-to-left cardiac and pulmonary shunts. A fluorescing indicator is injected into the bloodstream of a subject. An optical sensor is used to transcutaneously excite the indicator into fluorescence and to transcutaneously detect the fluorescence, and a relative concentration of the indicator is determined as a function of time. An indicator dilution curve is generated from the relative concentration readings, the curve shape is analyzed for the indication of a shunt and, if a shunt is detected, a ratiometric area under the curve analysis is performed and combined with a calculated cardiac output value to provide a shunt conductance value. A Valsalva maneuver may be performed as a part of the method. System embodiments may include a controller/monitor that monitors, times, cues and/or analyzes various steps of a shunt detection test.

Abstract: A system, method and apparatus are disclosed for using a transcutaneous detection system to measure the quantity of a circulating organ activity detection analyte in the blood, and thereby assay the activity of an organ. A preferred organ for assay is the human liver and a preferred indicator is indocyanine green (ICG) dye The procedure is under the control of a monitor/controller having a visual display and capable of providing cues to the operator. A sensor array apparatus for use in conjunction with the system monitor/controller is configured for increased sensitivity of assaying organ function.

Abstract: The preferred indicator is an injection of indocyanine green dye which is detected and quantified by causing it to fluoresce at a sensor location, for example, at the human ear. Quantification is carried out by using cardiac output procedures and where called for, the Valsalva Maneuver is monitored at a monitor/controller giving visual cues to the patient and operator as to the quality of the necessary exhalation pressure maintenance.

Abstract: A system and method for measuring total circulating blood volume and cardiac output employing an analyte diffusion approach. The analyte sensor as well as the analyte-containing fluid infusion procedure may be carried out with instruments which are inserted in the bloodstream at peripheral locations of the body spaced from the heart. A controller is provided to automatically carry out these measurements as well as to provide threshold comparisons for alerting the practitioner to excursion in the parameters. The preferred analyte containing fluid is an ammoniacal fluid and the preferred sensed components is ammonia gas.

Abstract: Total ammoniacal concentration (TAC) in blood is measured and displayed on a repetitive basis by a controller driven sensor arrangement which may be utilized either with a catheter structure or with a bypass system. The catheter based sensors may be employed with a peripheral region of the vascular system of the body. Repetitive measurements are carried out and these measurements are subjected to a moving average filtering procedure, whereupon the filtered TAC values are displayed numerically and graphically. The controller functions to compute the rate-of-rise of TAC and compares that value with a threshold rate-of-rise valuation which is inputted by the practitioner. Threshold values for TAC also may be inputted and the system not only provides alarm warnings for threshold excursions in TAC above threshold or excursions in rate-of-rise of TAC above threshold but also provides a visual cuing as a warning that TAC is elevating from one filtered measurement to the next.

Abstract: Cardiac output is measured utilizing a catheter in conjunction with the indicator dilution technique. Non-thermal analyte-containing fluid is used as the injectate. This fluid is biocompatible with and metabolizable within the body of the patient. An analyte concentration sensor is mounted upon the catheter and located downstream within the bloodstream from the port from which the analyte-containing fluid is expressed. Because of the matching of rapid concentration sensor response with an analyte-containing fluid which is metabolizable, the measurement of cardiac output may be carried out as often as about one to three minutes in conjunction with an infusion interval substantially less than the measurement frequency interval. The analyte-containing fluids are selected from a group consisting of ammoniacal fluid, heparin, ethanol, a carbon dioxide releasing fluid, glucose, and anesthesia agent.