Electrolytes clinical significance

Side effects from crystalloids primarily involve fluid overload and electrolyte disturbances of sodium, potassium, and chloride.23 Dilution of coagulation factors can also occur resulting in a dilutional coagulopathy.24 Two clinically significant reasons LR is different from NS is that LR contains potassium and has a lower sodium content (130 versus 154 mEq/L or mmol/L). Thus, LR has a greater potential than NS to cause... 

Most of the clinically significant cephalosporin antibiotics possess a sulfenyl group at the C-3 position. The electrolytic ene-type chlorination products 2 are potent intermediates for the synthesis of 3 -substituted cephalosporins 6 (Scheme 2-2)8). 

GRAPEFRUIT JUICE IMATINIB Likely interaction, t imatinib levels with t risk of toxicity (e.g. abdominal pain, constipation, dyspnoea) and of neurotoxicity (e.g. taste disturbances, dizziness, headache, paraesthesia, peripheral neuropathy) Due to inhibition of CYP3A4-mediated metabolism of imatinib. Clinical significance is not yet known as the interaction has not been scientifically tested Monitor for clinical efficacy and for the signs of toxicity listed, along with convulsions, confusion and signs of oedema (including pulmonary oedema). Monitor electrolytes, liver function and for cardiotoxicity... 

GAB-88 is an infusion solution containing amino acids (3%), dextrose (7.5%), and electrolytes in a dual-chamber plastic bag. It has been evaluated in 39 non-operative patients who were unable to tolerate oral feeding or to take adequate amounts by mouth (1). When it was given in a daily dose of 1.0-2.5 liters for 7-19 days, there was an improvement in nutritional status without obvious adverse effects. There was mild vascular pain in four patients, but no phlebitis. There were no other clinically significant adverse reactions. 

Medications in this class include delavirdine, efa-virenz, and nevirapine. Similar to the NRTls, these agents bind to viral reverse transcriptase and block DNA polymerase activity. A key difference is that NNRTIs do not require intracellular phosphorylation and are not incorporated into viral DNA. Clinically significant kidney toxicities or specific fluid-electrolyte complications have not been reported with this class of agents. In the rat model, efavirenz was associated wifh a species specific dependent kidney toxicity which occurred secondary to the development of a unique glutathione conjugate produced as a metabolite of efavirenz associated with renal tubular epifhelial cell necrosis [125-126]. This toxicity has not been observed in humans. One patient was recently reported to have reversible nephrotic-range proteinuria attributed to efavirenz use, in which a kidney biopsy showed diffuse podocyte foot process effacement [127]. Another report noted the development of rhabdomyolysis and acute tubular necrosis as a result of a drug interaction between delavirdine and atorvastatin [128]. Kidney toxicity due to nevirapine has not been reported. 

In addition to vasodilatory responses, PGs have a number of other effects in the kidney. For example, PGs stimulate adenylate cyclase in juxtaglomerular cells, resulting in an increase in cAMP production this, in turn, increases renin release. Renin stimulates the release of aldosterone, which increases renal tubular secretion of potassium (Stillman Schlesinger 1990). PGs also enhance tubular excretion of sodium and water (Patrono Dunn 1987). By causing these effects in the kidneys, PGs can alter electrolyte homeostasis. Therefore, other renal side-effects of NSAID therapy can include hyperkalemia, hypernatremia and edema. Often these metabolic changes are not observed in individuals with normal renal function, but in the presence of pre-existing disease they can become clinically significant. 

Alterations of HCOj and CO2 dissolved in plasma are characteristic of acid-base imbalance. Its value has most significance in the context of other electrolyte values and with blood gases and pH values. The full clinical significance of the determination of total CO2 wiU become apparent in the following discussion of acid-base physiology. 

The concentration of serum electrolytes may also be altered secondary to the development of respiratory alkalosis. The serum chloride concentration is usually slightly increased, and serum potassium concentration may be slightly decreased. Clinically significant hypokalemia can be a consequence of extreme respiratory alkalosis, although the effect is usually very small or negligible. Serum phosphorus concentration may decrease by as much as 1.5 to 2.0 mg/dL because of the shift of inorganic phosphate into cells. Reductions in the blood ionized calcium concentration may be partially responsible for symptoms such as muscle cramps and tetany. Approximately 50% of calcium is bound to albumin, and an increase in pH results in an increase in binding." ... 

Drugs in this class include delavirdine, efavirenz, and nevirapine. These drugs bind to viral reverse transcriptase and block DNA polymerase activity. Unlike the NRTIs, these drugs do not require intracellular phosphorylation and are not incorporated into viral DNA. None of these drugs has been associated with any clinically significant renal toxicities or specific fluid-electrolyte complications, and they do not appear to affect mitochondrial DNA polymerases. There is a... 

In this chapter, we discuss specifically the practical aspects of clinical analyses. The clinically significant constituents of blood and urine are described, including major electrolytes, proteins, and organic substances. Some of the commonly used analytical procedures for important clinical determinations, that is, the normal physiological ranges of the constituents and the conditions under which they may fall outside this range, are given. Also, the sensitive technique of immunoassay is described. 

In a study in 73 healthy subjects, celecoxib 400 mg was given daily for 2 weeks, then selenium enriched baker s yeast (Saccharomyces cerevi-siae) 200 micrograms daily or matched placebo were added for 30 days. Following blood chemistry analysis (urea and electrolytes, full blood count etc), there were no clinically significant changes from baseline, nor were there any changes in celecoxib steady-state plasma levels. ... 

Meloxicam 15 mg daily for 3 days had no significant effect on the pharmacokinetics of furosemide 40 mg in 12 healthy subjects. The furosem-ide-induced diuresis was unchanged, and although the cumulative urinary electrolyte excretion was somewhat lower, but this was not considered to be clinically significant.A similar study in patients with heart failure taking an ACE inhibitor also found no clinically significant pharmacokinetic or pharmacodynamic interaction between furosemide and meloxicam. 

CLINICAL SIGNIFICANCE OF ELECTROLYTES 5.1. Water and Electrolyte Balance... 

Electrolyte balance Electrotyte disturbances are weU-recognized comphcations of all bowel preparations. Rarely, they can be of clinical significance, as in one case of seizures secondary to hyponatremia [86 ]. 

Reviews - Current views on the concepts of diuretic therapy, the pharmacology of the established diuretic drugs, the regulation of renal water metabolism, and the effects and clinical significance of electrolyte disturbances on renal function were discussed in informative summaries published in 1967. 

Clinical Applications Perhaps the area in which ion-selective electrodes receive the widest use is in clinical analysis, where their selectivity for the analyte in a complex matrix provides a significant advantage over many other analytical methods. The most common analytes are electrolytes, such as Na+, K+, Ca +, H+, and Ch, and dissolved gases, such as CO2. For extracellular fluids, such as blood and urine, the analysis can be made in vitro with conventional electrodes, provided that sufficient sample is available. Some clinical analyzers place a series of ion-selective electrodes in a flow... 

Sodium phosphate is available as a nonprescription liquid formulation and by prescription as a tablet formulation. When taking these agents, it is very important that patients maintain adequate hydration by taking increased oral liquids to compensate for fecal fluid loss. Sodium phosphate frequently causes hyperphosphatemia, hypocalcemia, hypernatremia, and hypokalemia. Although these electrolyte abnormalities are clinically insignificant in most patients, they may lead to cardiac arrhythmias or acute renal failure due to tubular deposition of calcium phosphate (nephrocalcinosis). Sodium phosphate preparations should not be used in patients who are frail or elderly, have renal insufficiency, have significant cardiac disease, or are unable to maintain adequate hydration during bowel preparation. 

The major important organic electrolytes and nonelectrolytes transported by epithelial cells include sugars, amino acids, nucleosides, organic cations, and organic anions. Transport systems have significant implications for the absorption, distribution, elimination, and pharmacokinetic properties of many clinically important drugs. The major epithelial tissues... 

Since chronic renal insufficiency is frequently complicated by rises in serum potassium, phosphate, and magnesium, parenteral nutrition solutions used to treat malnourished patients with chronic renal insufficiency are usually prepared with little supplementation of these cations. Four patients with chronic renal insufficiency developed significant hypophosphatemia 3-5 days after starting parenteral nutrition. Other electrolyte abnormalities included hypomagnesaemia (n = 1) and hypokalemia (n — 3) (50). Hypophosphatemia may be the most significant of the electroljde risks in this clinical setting, and the electrolytes of such patients should be monitored closely when nutritional support is begun. 

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