Blood potassium

Potassium-sparing by diuretic agents, particularly spironolactone, enhances the effectiveness of other diuretics because the secondary hyperaldosteronism is blocked. This class of diuretics decreases magnesium excretion, eg, amiloride can decrease renal excretion of potassium up to 80%. The most important and dangerous adverse effect of all potassium-sparing diuretics is hyperkalemia, which can be potentially fatal the incidence is about 0.5% (50). Therefore, blood potassium concentrations should be monitored carehiUy. 

Electrolyte imbalances that may be seen during therapy with a diuretic include hyponatremia (low blood sodium) and hypokalemia (low blood potassium), although other imbalances may also be seen. See Chapter 58 and Display 58-2 for the signs and symptoms of electrolyte imbalances. The primary care provider is notified if any signs or symptoms of an electrolyte imbalance occur. 

The most common imbalances are a loss of potassium and water. Other electrolytes, namely magnesium, sodium, and chlorides, are also lost. When too much potassium is lost, hypokalemia (low blood potassium) occurs (see Home Care Checklist Preventing Potassium Imbalances). In certain patients, such as those also receiving a digitalis glycoside or those who currently have a cardiac arrhythmia, hypokalemia has the potential to create a mo re serious arrhythmia Hypokalemia is... 

Analysers for clinical purposes have been designed [129-131] and even a bedside analyser for monitoring Na, K, Cs and jJ-D-glucose in patients blood [127] or a blood potassium analyser for use during open-heart surgery [109]. A computer-controlled interference correction has been proposed [44], in which the standards are mixed to match the electrode potential obtained in the test solution. A simple caUbration in flow systems [61] involves dilution of the standard solution and monitoring of the ISE potential as a function of the diluent volume and dilution time. 

Do not take with diuretics or if you have low blood potassium or magnesium levels... 

Alpha blockers also produce certain metabolic effects such as inhibitory action of adrenaline on insulin secretion is blocked and adrenaline induced rise in blood potassium level is also blocked. 

Hyposecretion of hormones from the adrenal cortex leads to development of Addison s disease which is characterized by loss of appetite, muscular weakness, loss of weight due to loss of water, hypoglycemia, subnormal body temperature, decreased basal metabolic rate, increased blood potassium, decreased blood sodium and inability to maintain the normal protein deposition in the muscles. 

Ethylenediamine tetraacetic acid (EDTA) [60-00-4] (Sequestrene), an anticoagulent at 1 mg of the disodium salt per mT. blood, complexes with and removes calcium, Ca2+, from the blood. Oxalate, citrate, and fluoride ions form insoluble salts with Ca2+ and chelate calcium from the blood. Salts containing these anticoagulants include lithium oxalate [553-91-3] LyC204, 1 mg/mL blood sodium oxalate [62-76-0] Na2C204, 2 mg/mL blood potassium oxalate monohydrate [6487-48-5] H20, 2 mg/mL blood sodium fluoride [7681-49-4] NaF, 2 mg/mL blood trisodium citrate... 

Hematological Effects. No reliable studies were available regarding hematological effects in humans or animals following inhalation or dermal exposure to barium. There is suggestive evidence from case reports that acute inhalation, oral, and dermal exposure of humans is associated with lowered blood potassium levels (Diengott et al. 1964 Gould et al. 1973 Lewi and Bar- Khayim 1964 Phelan... 

CARBONIC ANHYDRASE INHIBITORS BRONCHODILATORS -BETA-2 AGONISTS, THEOPHYLLINE Risk of hypokalaemia Additive effects Monitor blood potassium levels prior to concomitant administration and during therapy. Administer potassium supplements to prevent hypokalaemia... 

THEOPHYLLINE CORTICOSTEROIDS Risk of hypokalaemia Additive effect. The CSM notes that this effect occurs with beta-2 agonists, theophyllines and corticosteroids, all of which may be given during severe asthma hypoxia exacerbates this effect Monitor blood potassium levels prior to concomitant administration and during therapy (monitor 1—2-hourly during parenteral administration). Administer potassium supplements to prevent hypokalaemia, which may also be worsened by hypoxia during severe attacks of asthma... 

Hyperkalemia is an infrequent problem associated with the massive transfusion of old blood. Potassium intoxication threatens only patients with raised potassium concentrations before transfusion, for example in the crush syndrome, renal insufficiency, and extensive bums. 

Blood concentration - increased (hemoconcentration) Blood potassium - decreased Stool oocytes - positive... 

Blood creatine phosphokinase (CPK) - increased Blood creatinine - increased Blood phosphate - decreased Blood potassium - decreased Blood urea nitrogen - increased... 

Interpret only in the context of other factors, esp low blood potassium and hypoxia, which increase sensitivity to digitalis... 

Izquierdo, J. M., Ferrero, J., Romeo, D., Badia, J. L. S., and Vigil, E. R., Capillary blood potassium chloride, sodium, calcium, phosphorus and alkaline phosphatase in the newborn. Clin. Chim. Acta 30, 343-346 (1970). 

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