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When serum potassium is less than 3.5, the condition hypokalemia is suggested. There can be many causes of hypokalemia, and it is important to find out why potassium levels are low, not assuming it is merely a low potassium intake.
Causes
Nutritional: Poor potassium intake, IV fluids low in potassium (if hospitalized), anorexia, a high carbohydrate diet.
GI Loss: Diarrhea, vomiting, malabsorbtion, intestinal fistula, ureterosigmoidostomy, laxative/enema use.
Renal Loss: Renal tubular acidosis, chronic renal disease, Fanconi's syndrome, Barter's Syndrome, Liddle's Syndrome, Gentamicin, Amphotericin, Carbenicillin or diuretic use.
Endocrine: Insulin therapy, glucose therapy, diabetic ketoacidosis, GI drainage, hyperaldosteronism, congenital adrenal hyperplasia, hypokalemic periodic paralysis, exogenous mineralocorticoids, Adrenal adenomas, Leukemia (pseudohypokalemia).
Alkalosis is associated with low potassium also. Potassium is necessary for proper nerve conduction, and cardiac arrhythmia is the most serious consequence of this condition.
The clinical signs of hypokalemia include weakness, silent distention of the abdomen, dyspnea, cardiac arrhythmia, and EKG changes. Serum potassium levels are usually low, but may be normal in spite of intracellular depletion (as is common in diabetic ketoacidosis). Many of the causes are renal; these may be divided into those associated with hypertension (secondary to hyperaldosteronism and hyperreninism) versus normotensive causes which affect tubular function. Symptoms start to appear when serum potassium drops below 3.0. These symptoms include: hyperglycemia, carbohydrate intolerance, sodium retention and edema, hyposthenia causing polyuria and polydipsia, and neuromuscular signs such as weakness, paralysis, intestinal ileus, autonomic insufficiency with orthostatic hypotension, lethargy and confusion. Cardiac arrhythmias may also develop.
Conventional treatment
If the potassium is less than 3, or symptoms are present, the patient should be placed on a cardiac monitor during treatment. Urine output should be measured to make sure that urine is produced, and that potassium will not accumulate to toxic levels. Unlike treatment of hyponatremia, potassium replacement is not a matter of calculating a correction based on serum potassium levels, since these are a poor reflection of the overwhelming proportion of potassium that is intracellular. Except for emergency management, potassium replacement should proceed slowly to allow equilibration. Large intravenous loads of potassium should be avoided. Potassium can be given by mouth, using 3 mEq/kg/day in addition to maintenance requirements. The citrate salt is more palatable than the chloride salt.
The approximate total body potassium is 55 meq/kg. When serum potassium (K+) is decreased by 1 meq/dl: there is an approximate 350 meq K+ deficit. When serum potassium is less than 2 meq/dl: there is an approximate 1000 meq K+ deficit.
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GLOSSARY
Anorexia Nervosa: An eating disorder characterized by excess control - a morbid fear of obesity leads the sufferer to try and limit or reduce their weight by excessive dieting, exercising, vomiting, purging and use of diuretics. Sufferers are typically more than 15% below the average weight for their height/sex/age and typically have amenorrhea (if female) or low libido (if male). 1-2% of female teenagers are anorexic.
Arrhythmia: A condition caused by variation in the regular rhythm of the heartbeat. Arrhythmias may cause serious conditions such as shock and congestive heart failure, or even death.
Carbohydrates: The sugars and starches in food. Sugars are called simple carbohydrates and found in such foods as fruit and table sugar. Complex carbohydrates are composed of large numbers of sugar molecules joined together, and are found in grains, legumes, and vegetables like potatoes, squash, and corn.
Cardiac: Pertaining to the heart, also, pertaining to the stomach area adjacent to the esophagus.
Chronic: Usually Chronic illness: Illness extending over a long period of time.
Copper: An essential mineral that is a component of several important enzymes in the body and is essential to good health. Copper is found in all body tissues. Copper deficiency leads to a variety of abnormalities, including anemia, skeletal defects, degeneration of the nervous system, reproductive failure, pronounced cardiovascular lesions, elevated blood cholesterol, impaired immunity and defects in the pigmentation and structure of hair. Copper is involved in iron incorporation into hemoglobin. It is also involved with vitamin C in the formation of collagen and the proper functioning in central nervous system. More than a dozen enzymes have been found to contain copper. The best studied are superoxide dismutase (SOD), cytochrome C oxidase, catalase, dopamine hydroxylase, uricase, tryptophan dioxygenase, lecithinase and other monoamine and diamine oxidases.
Diabetes Mellitus: A disease with increased blood glucose levels due to lack or ineffectiveness of insulin. Diabetes is found in two forms; insulin-dependent diabetes (juvenile-onset) and non-insulin-dependent (adult-onset). Symptoms include increased thirst; increased urination; weight loss in spite of increased appetite; fatigue; nausea; vomiting; frequent infections including bladder, vaginal, and skin; blurred vision; impotence in men; bad breath; cessation of menses; diminished skin fullness. Other symptoms include bleeding gums; ear noise/buzzing; diarrhea; depression; confusion.
Diarrhea: Excessive discharge of contents of bowel.
Diuretic: An agent increasing urine flow, causing the kidneys to excrete more than the usual amount of sodium, potassium and water.
Dyspnea: Difficult breathing.
Edema: Abnormal accumulation of fluids within tissues resulting in swelling.
Electrocardiogram: A test that shows a tracing of the electrical conduction of the heart.
Enzymes: Specific protein catalysts produced by the cells that are crucial in chemical reactions and in building up or synthesizing most compounds in the body. Each enzyme performs a specific function without itself being consumed. For example, the digestive enzyme amylase acts on carbohydrates in foods to break them down.
Fistula: An abnormal passageway, allowing movement between organs.
Gastrointestinal: Pertaining to the stomach, small and large intestines, colon, rectum, liver, pancreas, and gallbladder.
Gestational Diabetes: Gestational diabetes is defined as any degree of glucose intolerance with the onset or first recognition occurring during pregnancy. Many pregnant women do not notice any symptoms of diabetes, but urine and blood tests may show that they have it. Symptoms of diabetes may include thirst, weight loss, eating too much, urinating in large quantities and unexplained fatigue.
Glucose: A sugar that is the simplest form of carbohydrate. It is commonly referred to as blood sugar. The body breaks down carbohydrates in foods into glucose, which serves as the primary fuel for the muscles and the brain.
Hemorrhage: Profuse blood flow.
Hypertension: High blood pressure. Hypertension increases the risk of heart attack, stroke, and kidney failure because it adds to the workload of the heart, causing it to enlarge and, over time, to weaken; in addition, it may damage the walls of the arteries.
Hypokalemia: Abnormally low blood potassium.
Hypotension: Low blood pressure.
Ileus: Bowel obstruction.
Insulin: A hormone secreted by the pancreas in response to elevated blood glucose levels. Insulin stimulates the liver, muscles, and fat cells to remove glucose from the blood for use or storage.
Intravenous Infusion: (IV): A small needle placed in the vein to assist in fluid replacement or the giving of medication.
Kilogram: 1000 grams, 2.2lbs.
Laxative: A substance (food, herb, chemical) that stimulates evacuation of the bowels. Examples include cascara sagrada, senna, castor oil, aloe vera, bisacodyl, phenolphthalein and many others.
Leukemia: Cancer of the lymph glands and bone marrow resulting in overproduction of white blood cells (related to Hodgkin's disease).
Metabolism: The chemical processes of living cells in which energy is produced in order to replace and repair tissues and maintain a healthy body. Responsible for the production of energy, biosynthesis of important substances, and degradation of various compounds.
Polydipsia: Chronic excessive thirst.
Potassium: A mineral that serves as an electrolyte and is involved in the balance of fluid within the body. Our bodies contain more than twice as much potassium as sodium (typically 9oz versus 4oz). About 98% of total body potassium is inside our cells. Potassium is the principal cation (positive ion) of the fluid within cells and is important in controlling the activity of the heart, muscles, nervous system and just about every cell in the body. Potassium regulates the water balance and acid-base balance in the blood and tissues. Evidence is showing that potassium is also involved in bone calcification. Potassium is a cofactor in many reactions, especially those involving energy production and muscle building.
Serum: The cell-free fluid of the bloodstream. It appears in a test tube after the blood clots and is often used in expressions relating to the levels of certain compounds in the blood stream.
Sodium: An essential mineral that our bodies regulate and conserve. Excess sodium retention increases the fluid volume (edema) and low sodium leads to less fluid and relative dehydration. The adult body averages a total content of over 100 grams of sodium, of which a surprising one-third is in bone. A small amount of sodium does get into cell interiors, but this represents only about ten percent of the body content. The remaining 57 percent or so of the body sodium content is in the fluid immediately surrounding the cells, where it is the major cation (positive ion). The role of sodium in the extracellular fluid is maintaining osmotic equilibrium (the proper difference in ions dissolved in the fluids inside and outside the cell) and extracellular fluid volume. Sodium is also involved in nerve impulse transmission, muscle tone and nutrient transport. All of these functions are interrelated with potassium.
Stroke: A sudden loss of brain function caused by a blockage or rupture of a blood vessel that supplies the brain, characterized by loss of muscular control, complete or partial loss of sensation or consciousness, dizziness, slurred speech, or other symptoms that vary with the extent and severity of the damage to the brain. The most common manifestation is some degree of paralysis, but small strokes may occur without symptoms. Usually caused by arteriosclerosis, it often results in brain damage.
Signs, symptoms & indicators of Hypokalemia / Potassium Need:
