Blood electrolyte

Miniaturized catheter-type ISE sensors, such as the implantable probe shown in Figure 5-20 represent the preferred approach for routine clinical in-vivo monitoring of blood electrolytes. For these intravascular measurements the reference electrode is placed outside die artery (in die external arm of die catheter), tints obviating biocompatability and drift problems associated with its direct contact with the blood. 

FIGURE 5-20 Miniaturized ISE catheter sensor for continuous monitoring of blood electrolytes. (Reproduced with permission from reference 58.)... 

FIGURE 6-21 A silicon-based sensor array for monitoring various blood electrolytes, gases, and metabolites. (Courtesy of i-STAT Co.)... 

Background current, 21, 65 Background subtraction, 40, 106 Bacteria electrode, 182 Band microelectrodes, 130, 135 Beryllium, 82 Bienzyme electrodes, 175 Biocatalytic devices, 172 Biological recognition, 171 Biosensors, 50, 171 Bipotentiostat, 106 Blood electrolyte, 165 Boltzmann equation, 19 Brain analysis, 40, 116 Butler-Volmer equation, 14... 

The relative simplicity of the sensor setup allows them to be implemented into portable automated devices or bed-side analyzers (Fig. 4.2), which are easily installed at patient beds, eliminating the time-consuming laboratory analyses. On the other hand, modem high throughput clinical analyzers may process more than 1000 samples per hour and simultaneously determine dozens of analytes, using a handful of analytical methods. Blood electrolyte analysis, however, remains one of the most important in... 

R.W. Burnett, A.K. Covington, N. Fogh-Andersen, W.R. Kulpmann, A. Lewenstam, A.H.J. Maas, O. Muller-Plathe, A.L. Vankessel, and W.G. Zijlstra, Use of ion-selective electrodes for blood-electrolyte analysis. Recommendations for nomenclature, definitions and conventions. Clin. Chem. Lab. Med. 38, 363-370 (2000). 

The properties of a pH electrode are characterized by parameters like linear response slope, response time, sensitivity, selectivity, reproducibility/accuracy, stability and biocompatibility. Most of these properties are related to each other, and an optimization process of sensor properties often leads to a compromised result. For the development of pH sensors for in-vivo measurements or implantable applications, both reproducibility and biocompatibility are crucial. Recommendations about using ion-selective electrodes for blood electrolyte analysis have been made by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) [37], IUPAC working party on pH has published IUPAC s recommendations on the definition, standards, and procedures... 

Redox-inactive cations attract a particular interest for analytical chemists because of their importance in environmental control, industry, and medicine. For instance, in clinical diagnostics, tests for blood electrolytes (Na+, K+) are routine, because deviation of cation content from their normal values indicates a number of pathologies. 

E 67. A 76-year-old male with a combined history of bronchiogenic carcinoma and CHF is maintained on a diuretic to control pulmonary and peripheral edema. Recent measurement of blood electrolytes reveals an elevated serum Ca2. ... 

Mandatory studies Complete blood count Blood electrolytes Liver enzymes Urinalysis Vitamin B,2 level Folate level Syphilis (RPR/VDRL) Thyroid-stimulating hormone (TSH) Brain scan (CT or MRI) Electrocardiograph (EKG)... 

The tenn corticosteroids refers to steroid hormones secreted by the adrenal cortex. Corticosteroids are involved in a wide range of physiologic systems such as stress response, immune response, and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte levels, and behavior. 

Punte ec al.3 exposed volunteers to aerosol particles of 0.5-1.0 um. The windspeed was 5 mph. Figure 4-3 shows the variability in response times, especially at low concentrations. These experiments were continued with exposures at various temperatures, with exercise, and with repeated exposures and long low-concentration exposures to develop tolerance. High temperatures and humidity reduce the response time, as does exercise. After tolerance was developed, men given simple problems required more time to complete them, but accuracy was not impaired. Airway resistance did not increase during exposure to CS. One group exposed 10 times over 2 wk at up to 13 mg/m3 had normal blood electrolytes. Only minor adverse effects were observed in 75 men exposed in these experiments. 

No effect on blood electrolytes was observed in Sprague-Dawley rats receiving up to 12 mg/kg/day for 98 weeks (Kirchner et al. 1991). 

Today the determination of blood gases (p02, pC02) is performed using electrochemical GSSs, while major blood electrolytes (Na+, K+, Cl as well as Ca2+, Mg2+, Li+ as a therapeutic ion and pH) and main urine electrolytes (Na+, K+) are predominantly determined by electrochemical ISSs or ISEs. Some important metabolites (glucose, lactate, urea, creatinine) are often determined with electrochemical biosensors. 

However, in contrast to a direct measurement, where the analyte activity in the native sample is measured, in the indirect measurement (after dilution) this possibility is lost. In the latter case, only total concentration in a sample can be back-calculated . Additionally, because water plasma in a patient sample is not measured, the indirect method of measuring blood electrolytes in hyperlipemic/hyperproteinemic samples (i.e., in the cases of low plasma water vs. plasma volume) results in a negative bias compared to direct measurement (the bias is bigger with lower water content), while for samples with a high electrolyte content (i.e., high plasma water ionic strength) the indirect measurements will result in a positive bias. 

Measurement of ionized Mg + in human blood by ion-selective electrode in automatic blood electrolyte analyzer... 

The performance of the Mg-ISE in fully automated blood electrolyte analyzer was and may be evaluated according to the protocol presented above. 

The fact that 1 is fronting a host of molecular lumophore-spacer-receptor PET signaling systems appealed to Tusa, Leiner, and their collaborators at AVL Biosense Corporation, Atlanta, and Graz, Austria. Related sensory molecules now lie at the heart of blood electrolyte measurement in critical care units in hospitals [52], This is perhaps the clearest endorsement to date of the device capability of luminescent PET signaling systems. 

Potentiometric microelectrodes are very suitable for in vivo real-time clinical monitoring of blood electrolytes, intracellular studies, in situ environmental surveillance, or industrial process control. For example, Simon s group... 

Apart from specific antidotes (if they exist), the treatment of poisonings also calls for symptomatic measures (control of blood pressure and blood electrolytes monitoring of cardiac and respiratory function prevention of toxin absorption by activated charcoal). An important step is early emptying of the stomach by gastric lavage and, if necessary, administration of an osmotic laxative. Use of emetics (saturated NaCl solution, ipecac syrup, apomorphine s.c.) is inadvisable. 

From the symptoms and examination of blood and urine, a diagnosis of chronic renal failure is made. Unfortunately, considerable kidney damage can occur, often over a period of years, before the patient notices the symptoms associated with chronic renal failure. As the amount of functioning kidney tissue decreases, blood electrolytes begin to change. At the same time, the ability of the kidney to excrete nitrogenous waste decreases and urea concentration in the blood rises (uraemia). The patient may remain symptom-free until the concentration of urea rises sufficiently to cause the nausea and vomiting Kevin has recently experienced. 

Clement, J.G., Lee, M.J. (1980). Soman-induced convulsions significance of changes in levels of blood electrolytes, gases, glucose and insulin. Toxicol. Appl. Pharmacol. 55 203-4. 

Abnormal levels of blood electrolytes such as sodium and potassium can also cause neuromuscular disturbances. When potassium is too high or too low, the muscles of the trunk, arms, and legs can be very weak, even to the point of paralysis. If the blood calcium is low (as in vitamin D deficiency or inadequate function of the parathyroid gland), twitching may occur. When blood calcium is too high, there may be profound weakness. Normal magnesium levels are also important for proper neuromuscular functioning. 

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