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Fractional Sodium Excretion
The fractional excretion of sodium (FENa) is the percentage of the sodium filtered by the kidney which is excreted in the urine. It is measured in terms of plasma and urine sodium, rather than by the interpretation of urinary sodium concentration alone, as urinary sodium concentrations can vary with water reabsorption. Therefore, the urinary and plasma concentrations of sodium must be compared to get an accurate picture of kidney clearance. In clinical use, the fractional excretion of sodium can be calculated as part of the evaluation of acute kidney failure in order to determine if hypovolemia or decreased effective circulating plasma volume is a contributor to the kidney failure. Calculation FENa is calculated in two parts—figuring out how much sodium is excreted in the urine, and then finding its ratio to the total amount of sodium that passed through (aka "filtered by") the kidney. First, the actual amount of sodium excreted is calculated by multiplying the urine sodium con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute Kidney Failure
Acute kidney injury (AKI), previously called acute renal failure (ARF), is a sudden decrease in kidney function that develops within 7 days, as shown by an increase in serum creatinine or a decrease in urine output, or both. Causes of AKI are classified as either prerenal (due to decreased blood flow to the kidney), intrinsic renal (due to damage to the kidney itself), or postrenal (due to blockage of urine flow). Prerenal causes of AKI include sepsis, dehydration, excessive blood loss, cardiogenic shock, heart failure, cirrhosis, and certain medications like ACE inhibitors or NSAIDs. Intrinsic renal causes of AKI include glomerulonephritis, lupus nephritis, acute tubular necrosis, certain antibiotics, and chemotherapeutic agents. Postrenal causes of AKI include kidney stones, bladder cancer, neurogenic bladder, enlargement of the prostate, narrowing of the urethra, and certain medications like anticholinergics. The diagnosis of AKI is made based on a person's signs and symp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urinary Flow Rate
Urine flow rate or urinary flow rate is the volumetric flow rate of urine during urination. It is a measure of the quantity of urine excreted in a specified period of time (per second or per minute). It is measured with uroflowmetry, a type of flow measurement. The letters "V" (for volume) and "Q" (a conventional symbol for flow rate) are both used as a symbol for urine flow rate. The V often has a dot (overdot), that is, V̇ ("V-dot"). Qmax indicates the maximum flow rate. Qmax is used as an indicator for the diagnosis of enlarged prostate. A lower Qmax may indicate that the enlarged prostate puts pressure on the urethra, partially occluding it. Uroflowmetry is performed by urinating into a special urinal, toilet, or disposable device that has a measuring device built in. The average rate changes with age. Clinical usage Changes in the urine flow rate can be indicative of kidney, prostate or other renal disorders. Similarly, by measuring urine flow rate, it is possible to calcu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glomerular Filtration Rate
Renal functions include maintaining an acid–base balance; regulating fluid balance; regulating sodium, potassium, and other electrolytes; clearing toxins; absorption of glucose, amino acids, and other small molecules; regulation of blood pressure; production of various hormones, such as erythropoietin; and activation of vitamin D. One of the measures of kidney function is the glomerular filtration rate (GFR). Glomerular filtration rate describes the flow rate of filtered fluid through the kidney. Creatinine clearance rate (CCr or CrCl) is the volume of blood plasma that is cleared of creatinine per unit time and is a useful measure for approximating the GFR. Creatinine clearance exceeds GFR due to creatinine secretion, which can be blocked by cimetidine. Both GFR and CCr may be accurately calculated by comparative measurements of substances in the blood and urine, or estimated by formulas using just a blood test result (eGFR and eCCr) The results of these tests are used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is 23Na. The free metal does not occur in nature, and must be prepared from compounds. Sodium is the sixth most abundant element in the Earth's crust and exists in numerous minerals such as feldspars, sodalite, and halite (NaCl). Many salts of sodium are highly water-soluble: sodium ions have been leached by the action of water from the Earth's minerals over eons, and thus sodium and chlorine are the most common dissolved elements by weight in the oceans. Sodium was first isolated by Humphry Davy in 1807 by the electrolysis of sodium hydroxide. Among many other useful sodium compounds, sodium hydroxide (lye) is used in soap manufacture, and sodium chloride (edible salt) is a de-icing agent and a nutrient for animals including h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Creatinine
Creatinine (; ) is a breakdown product of creatine phosphate from muscle and protein metabolism. It is released at a constant rate by the body (depending on muscle mass). Biological relevance Serum creatinine (a blood measurement) is an important indicator of kidney health, because it is an easily measured byproduct of muscle metabolism that is excreted unchanged by the kidneys. Creatinine itself is produced via a biological system involving creatine, phosphocreatine (also known as creatine phosphate), and adenosine triphosphate (ATP, the body's immediate energy supply). Creatine is synthesized primarily in the liver from the methylation of glycocyamine (guanidino acetate, synthesized in the kidney from the amino acids arginine and glycine) by S-Adenosyl methionine. It is then transported through blood to the other organs, muscle, and brain, where, through phosphorylation, it becomes the high-energy compound phosphocreatine. Creatine conversion to phosphocreatine is catalyzed b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oliguria
Oliguria or hypouresis is the low output of urine specifically more than 80 ml/day but less than 400ml/day.Boon et al, Davidson's Principles & Practice of Medicine (20th Ed), p475 The decreased output of urine may be a sign of dehydration, kidney failure, hypovolemic shock, hyperosmolar hyperglycemic nonketotic syndrome (HHNS), multiple organ dysfunction syndrome, urinary obstruction/urinary retention, diabetic ketoacidosis (DKA), pre-eclampsia, and urinary tract infections, among other conditions. Beyond oliguria is anuria, which represents an absence of urine, clinically classified as below 80 or 100 ml/day. The term oliguria is derived from ''oligo''-meaning "small, little," + -''uria'', from the Greek word ''ouron,'' meaning ''"''urine". Definition Oliguria is defined as a urine output that is less than 1 mL/kg/h in infants,Free Full T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute Tubular Necrosis
Acute tubular necrosis (ATN) is a medical condition involving the death of tubular epithelial cells that form the renal tubules of the kidneys. Because necrosis is often not present, the term acute tubular injury (ATI) is preferred by pathologists over the older name acute tubular necrosis (ATN). ATN presents with acute kidney injury (AKI) and is one of the most common causes of AKI. Common causes of ATN include low blood pressure and use of nephrotoxic drugs. The presence of "muddy brown casts" of epithelial cells found in the urine during urinalysis is pathognomonic for ATN. Management relies on aggressive treatment of the factors that precipitated ATN (e.g. hydration and cessation of the offending drug). Because the tubular cells continually replace themselves, the overall prognosis for ATN is quite good if the underlying cause is corrected, and recovery is likely within 7 to 21 days. Classification ATN may be classified as either ''toxic'' or ''ischemic''. Toxic ATN occurs whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diuretic
A diuretic () is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. A diuretic tablet is sometimes colloquially called a water tablet. There are several categories of diuretics. All diuretics increase the excretion of water from the body, through the kidneys. There exist several classes of diuretic, and each works in a distinct way. Alternatively, an antidiuretic, such as vasopressin ( antidiuretic hormone), is an agent or drug which reduces the excretion of water in urine. Medical uses In medicine, diuretics are used to treat heart failure, liver cirrhosis, hypertension, influenza, water poisoning, and certain kidney diseases. Some diuretics, such as acetazolamide, help to make the urine more alkaline, and are helpful in increasing excretion of substances such as aspirin in cases of overdose or poisoning. Diuretics are sometimes abused by people with an eating disorder, especially people with bulimia nervosa, with the goa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prerenal Disease
Acute kidney injury (AKI), previously called acute renal failure (ARF), is a sudden decrease in kidney function that develops within 7 days, as shown by an increase in serum creatinine or a decrease in urine output, or both. Causes of AKI are classified as either prerenal (due to decreased blood flow to the kidney), intrinsic renal (due to damage to the kidney itself), or postrenal (due to blockage of urine flow). Prerenal causes of AKI include sepsis, dehydration, excessive blood loss, cardiogenic shock, heart failure, cirrhosis, and certain medications like ACE inhibitors or NSAIDs. Intrinsic renal causes of AKI include glomerulonephritis, lupus nephritis, acute tubular necrosis, certain antibiotics, and chemotherapeutic agents. Postrenal causes of AKI include kidney stones, bladder cancer, neurogenic bladder, enlargement of the prostate, narrowing of the urethra, and certain medications like anticholinergics. The diagnosis of AKI is made based on a person's signs and symptom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azotemia
Azotemia (''azot'', "nitrogen" + '' -emia'', "blood condition") is a medical condition characterized by abnormally high levels of nitrogen-containing compounds (such as urea, creatinine, various body waste compounds, and other nitrogen-rich compounds) in the blood. It is largely related to insufficient or dysfunctional filtering of blood by the kidneys. It can lead to uremia and acute kidney injury (kidney failure) if not controlled. Types Azotemia has three classifications, depending on its causative origin: prerenal azotemia, renal azotemia, and postrenal azotemia. Measurements of urea and creatinine (Cr) in the blood are used to assess renal function. For historical reasons, the lab test measuring urea is known as "blood urea nitrogen" (BUN). The BUN:Cr ratio is a useful measure in determining the type of azotemia and will be discussed in each section below. A normal BUN:Cr is equal to 15. Prerenal azotemia Prerenal azotemia is caused by a decrease in blood flow (hypoperfusion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urinary Index
The urinary indices are the fractional sodium excretion (FENa) index and the renal failure index (RFI). The renal failure index = Urine Sodium * Plasma Creatinine / Urine Creatinine Creatinine (; ) is a breakdown product of creatine phosphate from muscle and protein metabolism. It is released at a constant rate by the body (depending on muscle mass). Biological relevance Serum creatinine (a blood measurement) is an import .... References Urine tests {{med-diagnostic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cornell University
Cornell University is a private statutory land-grant research university based in Ithaca, New York. It is a member of the Ivy League. Founded in 1865 by Ezra Cornell and Andrew Dickson White, Cornell was founded with the intention to teach and make contributions in all fields of knowledge—from the classics to the sciences, and from the theoretical to the applied. These ideals, unconventional for the time, are captured in Cornell's founding principle, a popular 1868 quotation from founder Ezra Cornell: "I would found an institution where any person can find instruction in any study." Cornell is ranked among the top global universities. The university is organized into seven undergraduate colleges and seven graduate divisions at its main Ithaca campus, with each college and division defining its specific admission standards and academic programs in near autonomy. The university also administers three satellite campuses, two in New York City and one in Education City, Qatar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
