Abstract: An apparatus and a method for determining the volume amount of a physiological volume (EVLW) from the system response to two successive system disturbances, taking into account that an intrinsic physical property of the physiological volume is influenced by the first (or previous, respectively) system disturbance, is described. By introducing a cold bolus to the central venous blood stream, a flowed-by volume, such as extravascular lung water, is cooled down. The driving temperature gradient for heat transfer is reduced when a second cold bolus is introduced. From the difference of the system response to the first bolus injection and the second bolus injection EVLW can be determined.

Abstract: The apparatus comprises a pressure sensor providing readings of a blood pressure of the patient and storage means for storing the readings as a pressure curve over time. Blood pressure is measured. The frequency difference between heart rate and breathing rate is used to separate the respiratory effect from the heart activity. In particular, the Fourier transform of the blood pressure and the spectral density are used to determine the contribution of each frequency. The respiratory and cardiac power spectra are determined. The ratio between both powers is calculated as the quotient of the integrals over the cardiac power spectrum and the respiratory power spectrum. A parameter usable to characterize volume responsiveness is determined using above ratio and a correction factor.

Abstract: A relation is formed between an n-tuple having n components and formed at a first point in time and at least one other n-tuple having n components formed at at least one corresponding later point in time, wherein n is a natural number equal to or greater than 1, and the components comprise at least one derived parameter and/or one read-in data value. If this relationship satisfies a predetermined calibration criterion, a calibration signal is triggered and is displayed, and/or automatically triggers a recalibration of the haemodynamic monitoring device. For example, the pulse contour cardiac output PCCO is derived from the arterial pressure curve as the constituent component of a 1-tuple. As long as this differs from the reference cardiac output CORef by less than a predefined threshold value, for example 101 or 15% of the reference cardiac output, parameter determination continues without initiating a new calibration.

Abstract: A device for the continuous measurement of the flow rate of a liquid, in particular the urine of a living being, comprising at least two receiving containers (2, 3) for receiving the liquid, a tubular or hose-like connection part (4) at the lower end of the first receiving container (2), which connection part connects the first receiving container (2) to the second receiving container (3), a first seal (6a/6b) between the first receiving container (2) and the second receiving container (3) at the tubular or hose-like connection part (4), a second seal (7) at the lower end of the second receiving container (3), and a rising pipe (8) which is connected to the second receiving container (3), wherein a measuring device (10) arranged in the region of the upper end of the rising pipe (8).

Abstract: The invention relates to a catheter device with an integrated fiber optic, in particular for use in thermodilution measurement and pulse contour analysis. The device comprises an arterial catheter (2) with a suitable intravascular part and a suitable extravascular part and an optical sensor unit for combined pressure and temperature measurement at a measurement location at the distal end of the suitable intravascular part or proximate to the distal end of the proper intravascular part of the catheter (2). The optical sensor unit comprises a fiber optic conductor (11) that runs from the measurement location to a proximal port.

Abstract: The central venous sensor assembly comprises a catheter body with several proximal ports. The catheter portion placed in the vena cava superior is equipped with a proximal flux measurement unit, and the catheter portion placed in the vena cava inferior is equipped with a distal flux measurement unit. A first input channel supplies a measurement signal indicative of a flux vp to the evaluation unit from which the latter calculates a blood flow in the vena cava superior. Likewise, a second input channel supplies a measurement signal indicative of a flux vd to the evaluation unit from which the latter calculates a blood flow rate in the vena cava inferior. Due to continuity, the sum of the flow rates in the upper and lower central veins corresponds to the flow rate through the right heart and in the pulmonary artery and thus to cardiac output.

Abstract: From the global end-diastolic volume GEDV and the global ejection fraction GEF the patient monitor (4) determines a corrected global end-diastolic volume cGEDV according to cGEDV=GEDV/ƒ(GEF) which is used as a novel parameter for volume responsiveness of the patient (3). In the above formula, f(GEF) is a correction function depending on global ejection fraction GEF. Further, from the right ventricular end-diastolic volume RVEDV and the right ventricular ejection fraction RVEF the patient monitor (4) determines a corrected right ventricular end-diastolic volume cRVEDV according to cRVEDV=RVEDV1f(RVEF) which is used as another novel parameter for volume responsiveness of the patient (3). In the above formula, f(RVEF) is a correction function depending on right ventricular ejection fraction RVEF.

Abstract: An apparatus for determining physiologic parameters of a patient (6) comprises a pressure sensor adapted to provide readings of a blood pressure of the patient (6), which are stored as at least one pressure curve over time or a derivative thereof with respect to time, and evaluation means (4) adapted to determine, from the pressure curve or the derivative, at least one cardiac activity state variable representing cardiac activity over time and/or variation of cardiac activity over time, and to determine at least one cardiac preload state variable representing cardiac preload over time and/or variation of cardiac preload over time. The evaluation means (4) are further adapted to determine the physiologic parameter as a sum of a plurality of sum terms, at least one of which is a monotonous function of a cardiac activity state variable and at least another one of which is a monotonous function of a cardiac preload state variable.

Abstract: An apparatus for determining a physiological parameter of a patient, such as cardiac output, comprises a sensor device providing readings of a blood variable, memory means storing the readings as a curve over time, evaluation means determining a mean value from the curve and determining the physiological parameter using the mean value is provided. The evaluation means determine a spectral density of the curve and/or a variance. The evaluation means also determine at least one model parameter representing an effective value of a heart beat using the mean value and the spectral density and/or variance. The effective value is selected from an effective amplitude of the heart beat, an effective duration of the heart beat and an effective area under the heart beat. The physiological parameter is determined using at least one of the model parameters.

Abstract: The central venous sensor assembly comprises a catheter body with several proximal ports. The catheter portion placed in the vena cava superior is equipped with a proximal flux measurement unit, and the catheter portion placed in the vena cava inferior is equipped with a distal flux measurement unit. A first input channel supplies a measurement signal indicative of a flux vp to the evaluation unit from which the latter calculates a blood flow in the vena cava superior. Likewise, a second input channel supplies a measurement signal indicative of a flux vd to the evaluation unit from which the latter calculates a blood flow rate in the vena cava inferior. Due to continuity, the sum of the flow rates in the upper and lower central veins corresponds to the flow rate through the right heart and in the pulmonary artery and thus to cardiac output.

Abstract: The apparatus comprises a pressure sensor providing readings of a blood pressure of the patient and storage means for storing the readings as a pressure curve over time. Blood pressure is measured. The frequency difference between heart rate and breathing rate is used to separate the respiratory effect from the heart activity. In particular, the Fourier transform of the blood pressure and the spectral density are used to determine the contribution of each frequency. The respiratory and cardiac power spectra are determined. The ratio between both powers is calculated as the quotient of the integrals over the cardiac power spectrum and the respiratory power spectrum. A parameter usable to characterize volume responsiveness is determined using above ratio and a correction factor.

Abstract: A device for individual in-vivo determination of the compliance function C(p)=dV/dp of the vascular system downstream of a ventricle and/or systemic blood flow of a living being from the blood pressure p(t) and a reference cardiac output COref.

Abstract: The present invention relates to a process and devices for determining the instant of injection and the duration of injection in thermodilution measurements in which an injectate fluid at a temperature deviating from the temperature of the blood of a patient is injected at a specific injection site into a blood vessel of the patient and the temperature of the blood is measured at a measuring site downstream of the injection site, the injectate fluid being used at approximately room temperature and, before entry into the blood vessel, passed via a temperature sensor which, before the measurement, has a temperature deviating from room temperature, the temperature determined by the temperature sensor being sensed continuously, the instant of the beginning of injection being determined from a change occurring in the sensed temperature and the instant of the end of injection being determined from a subsequently occurring change in direction of the temperature profile.