Measuring and testing – Sampler – sample handling – etc. – Capture device
Patent
1992-01-29
1994-05-10
Raevis, Robert
Measuring and testing
Sampler, sample handling, etc.
Capture device
G01N 3506
Patent
active
053097750
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to apparatus for carrying out analysis of fluids, usually physiological fluids, including gases and, usually, liquids such as blood, which comprises an analyser and a vessel for storing a reagent liquid used in the measurement.
In many instances it is very important to obtain reliable information about certain data about a blood sample from a patient as soon as possible in order to avoid an unnecessary delay in treating the patient in the most appropriate manner. The data desired may comprise any of the following:
Partial pressure of carbon dioxide in the blood sample--in the following referred to as pCO.sub.2,
partial pressure of oxygen in the blood sample--in the following referred to as pO.sub.2,
the pH-value of the blood sample, and
the hemoglobin concentration of the blood sample, e.g. in percentage by weight--in the following referred to as Hb %.
When a correlated set of values for pCO.sub.2, pO.sub.2, pH, and Hb % is known, it is possible to determine a number of other parameters indicating the acid-base status of the blood sample, such as "buffer base", "base excess", "standard bicarbonate", "actual bicarbonate", "total CO.sub.2 ". These terms are well known in the art. Their calculation is described in U.S. Pat. No. 3,654,445 and in Ole Siggaard-Andersen, The Acid-Base Status of the Blood, 4th edition, Munksgaard, Copenhagen 1976.
The parameters of the fluid which are measured are generally measured by electrochemical measuring devices, often including electrodes, for instance including a pH electrode, a pCO.sub.2 electrode, and a pO.sub.2 electrode, and may also comprise photometric sensing devices, for instance which are useful to determine the Hb level. These measurements invariably involve the transmission of electrical signals by the analyser, those electrical signals often being the direct results of the measuring process. It is necessary to take precautions to ensure that there is as little interference to those electrical signals as possible.
The measurements of the various parameters are carried out in a measurement section of the analyser. This section may comprise separate measurement chambers within which each measurement is carried out, for instance each of which contains a single electrode, or the measurements may be carried out in one or more chambers of which at least one contains two or more of the measuring devices or all of the measurements may be carried out in a single measuring chamber.
It is clearly important in such apparatus to ensure that after measurement of the parameters of a sample have been made, the sample inlet section and the measuring section of the analyser are rendered completely free of all traces of that sample, before the next sample is introduced for measurement. This is achieved by flushing a rinsing solution through the conduits of the analyser including the sample inlet section and the measuring section. The solution for carrying out the rinsing is generally supplied to the analyser from a separate vessel containing a store of the solution.
As well as rinsing the conduits of the analyser between samples, it is also necessary periodically to calibrate the apparatus to ensure accuracy of the readings being obtained. The calibration is carried out by introducing into the measurement section standard calibrating solutions having known values for the respective parameter or parameters. As for the rinsing solution, it is convenient for a store of the calibrating solutions to be carried in storage vessels co-operating with the conduits of the analyser.
Where the analyser includes a pH electrode, as is normal, this is usually associated with a reference, calomel electrode. A salt bridge is formed between the reference electrode and the glass electrode of the pH measuring system. This salt bridge usually comprises potassium chloride solution. It is usual to maintain a store of potassium chloride solution associated with the analyser.
Apparatus of this type also includes a waste outlet through which all of the waste liquid is disposed
REFERENCES:
patent: D325257 (1992-04-01), Andersen et al.
patent: D325258 (1992-04-01), Andersen et al.
patent: D325259 (1992-04-01), Andersen et al.
patent: 3290920 (1966-12-01), Novak
patent: 3690833 (1972-09-01), Ferrari
patent: 4338280 (1982-07-01), Ambers et al.
patent: 4604263 (1986-08-01), Smernoff
patent: 4711851 (1987-12-01), McNamara et al.
patent: 4844871 (1989-07-01), Polaschegg
patent: 4889255 (1989-12-01), Schiemann
patent: 4928860 (1990-05-01), Knight
patent: 5185263 (1993-02-01), Kroneis et al.
Andersen Joergen
Hvidtfeldt Kristian J.
Sinnerup Ib O.
Radiometer A/S
Raevis Robert
LandOfFree
Apparatus for analysis of samples of fluids does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus for analysis of samples of fluids, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for analysis of samples of fluids will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2408236