Electrolytes Flashcards
Conditions that lead to hyponatremia
SIADH is a condition that can lead to hyponatremia. In SIADH, there is too much ADH. ADH causes water retention, and therefore too much water is retained. Due to the volume, so much water is retained in the vascular space that the amount of sodium present is relatively less than before. This is relative hyponatremia.
Addison’s disease can lead to hyponatremia. In Addison’s disease, there is decreased aldosterone secretion. Aldosterone functions to facilitate sodium reabsorption in the collecting ducts of the kidney. So, with less aldosterone, there is less sodium reabsorption, leading to less sodium (hyponatremia)
Psychogenic polydipsia is a condition that can lead to hyponatremia. In this condition, the client cannot stop drinking water. They drink so much water that they dilute their blood volume with free water. This large increase in free water causes relative hyponatremia.
causes of SIADH
surgery
Intracranial infection, injury or CVA
Alveola cancer/pus
Drugs such as opiates, anti epileptics, cytotoxins, antipsychotics
Hormonal causes such as hypothyroidism/low corticosteroid level
hyponatremia
Hyponatremia refers to a sodium level lower than 135 mEq/L. Hyponatremia may be secondary to several causes; however, it is possible to get clues regarding the cause of hyponatremia by determining the type of hyponatremia. Sodium and water go together. Sodium tends to draw and keep water with it—the decrease in sodium relative to free water results in hyponatremia.
A key nursing priority for the management of hyponatremia is assessing and monitoring the client’s neuromuscular status as they are at risk for orthostatic hypotension and seizures.
hyponatremia causes
medications such as diuretics, oral gastric tube suctioning, burns, SIADH, and failure of the heart, liver, or kidney.
Addison’s Disease Symptoms
hair loss, hyperpigmentation, postural hypotension, weakness, weight loss, GI disturbances, fatigue, hypoglycemias
Adrenal Crisis symptoms
extreme fatigue, dehydration, fever, hypotension, renal shut down, hyperkalemia, hyponatremia
Which diseases can cause hypervolemia?
Heart failure can cause hypervolemia. When the heart is not pumping effectively, there is decreased cardiac output. This means less perfusion to all of the body’s organs, including the kidneys. When the kidneys don’t get enough blood, the urinary output will decrease; instead of the body getting rid of fluid in the urine, the volume will stay in circulation and cause hypervolemia (Choice A). Renal failure can cause hypervolemia. If the kidneys are failing, they are not effectively making urine. If the body is not excreting fluid in the urine, that fluid is staying in the vascular space and causes hypervolemia (Choice B). Hormonal imbalances, such as those caused by excessive production of cortisol or aldosterone, can lead to an increase in fluid retention and hypervolemia.
ome contributing factors in the development of hypervolemia can be the following:
✓Heart failure: When the heart is unable to pump blood effectively, fluid can build up in the lungs and other parts of the body.
✓Kidney disease: The kidneys are responsible for removing excess fluid from the body. When they are not functioning properly, fluid can accumulate.
✓Liver disease: Liver disease can lead to a decrease in albumin production, which can result in fluid accumulation.
✓Excessive fluid intake: Receiving excessive IV fluids can lead to hypervolemia.
✓Hormonal imbalances: Hormones such as aldosterone can affect fluid balance in the body.
✓Medications: Certain medications, such as corticosteroids and nonsteroidal anti-inflammatory drugs (NSAIDs), can lead to fluid retention.
Hypotonic IV fluids
✓ Hypotonic IV fluids have a lower concentration of solutes than the body’s own fluids.
✓They are typically used to treat conditions where there is an excess of sodium in the body or to rehydrate patients with cellular dehydration.
D2.5 W is a hypotonic solution. 0.33% NS is a hypotonic solution
Selevamer
Sevelamer is a phosphate binder indicated in the treatment of hyperphosphatemia associated with chronic kidney disease. This medication is purported to decrease serum phosphorus levels by binding to food. Thus, this medication is given with meals. Combined with a low phosphorus diet, the goal of this medication is to decrease serum phosphate levels.
he goal of this medication is to decrease serum phosphorus, thereby raising serum calcium (calcium and phosphorus have a reciprocal relationship). Hyperphosphatemia is a common problem associated with chronic kidney disease and end-stage renal disease, and medications such as sevelamer are used in its management. These medications are not indicated for raising hemoglobin or decreasing serum potassium.
Hyperphosphatemia is a common problem associated with chronic kidney disease and end-stage renal disease, and medications such as sevelamer are used in its management.
➢ Management is with restricting dietary phosphorus combined with oral phosphate binders.
➢ Food sources with high levels of phosphorus include beans, fish, and nuts.
➢ These phosphate binders may be calcium-containing (calcium carbonate) and noncalcium-containing (sevelamer).
➢ These medications are only effective when taken with meals.
➢ Major side effects of these medications include constipation which may lead to paralytic ileus.
➢ Other side effects include vitamin deficiencies which is why a renal vitamin may be prescribed.
➢ Calcium and phosphorus levels should be monitored closely during the treatment.
Magnesium
Clients taking magnesium sulfate are expected to become sleepy during the daytime as well as experience hot flashes and lethargy.
Magnesium prevents or controls convulsions by blocking neuromuscular transmission and decreasing the amount of acetylcholine liberated at the endplate by the motor nerve impulse. Magnesium sulfate does not affect urine production.
The absence of deep tendon reflexes indicates elevated magnesium levels. As plasma magnesium rises above 4 mEq/liter, the deep tendon reflexes are decreased.
decreased respirations indicates magnesium toxicity. As the plasma level approaches 10 mEq/liter, respiratory paralysis may occur. A decrease in respiratory rate initially manifests this.
symptoms of hypernatremia
Sodium plays a vital role in the brain, so imbalances in the serum sodium level can cause significant neurological changes. The client who is hypernatremic, or has a sodium level greater than 145 mEq/L, is at risk for changes in their level of consciousness ranging from restlessness and agitation to lethargy (Choice A), stupor, and coma. A client with a high sodium level often has dry mucous membranes. Hypovolemic hypernatremia is the most common form of hypernatremia. Other causes include renal losses of free water (osmotic diuresis, post obstructive diuresis) or extrarenal losses (diarrhea, sweating, increased insensible losses). Therefore, the client is often dehydrated, and this fluid volume deficit is manifested by dry mucous membranes (Choice B) and excessive thirst (Choice E). Dry mucosa may also be secondary to the relationship sodium has with water. Water follows sodium, so where there is an increased sodium level in the extracellular space, water leaves the cells and follows the sodium into the extracellular space. This causes dry mouth and mucous membranes.
IV potassium Considerations
When replacing potassium intravenously:
✓ Ensure that the client is connected to continuous cardiac monitoring.
✓ IV potassium should be administered via a controlled device such as a pump.
✓ The IV site must be patent and assessed for patency before administration.
✓ Potassium should be administered at a maximum of 10 mEq/L/hr peripherally; 40 mEq/L/hr in a central line.
IV potassium Considerations
When replacing potassium intravenously:
✓ Ensure that the client is connected to continuous cardiac monitoring.
✓ IV potassium should be administered via a controlled device such as a pump.
✓ The IV site must be patent and assessed for patency before administration.
✓ Potassium should be administered at a maximum of 10 mEq/L/hr peripherally; 40 mEq/L/hr in a central line.
Based on a client’s laboratory data showing hyponatremia, hemodilution, and increased urine specific gravity (concentration), which condition should we suspect?
Based on the client’s laboratory data showing hyponatremia, hemodilution, and increased urine specific gravity (concentration), SIADH is highly likely. SIADH causes increased water retention thus leading to hemodilution and dilutional hyponatremia. The low urine output is also a feature (oliguria) and if urine is produced, it has a high specific gravity.
The normal serum sodium is 135-145 mEq/L; The normal hematocrit is 42-52% for males and 37-47% for females; The normal USG is 1.005 - 1.030
Peritoneal Dialysis
Osmosis is an essential principle upon which peritoneal dialysis functions. Osmosis is the passive movement of solvents, such as water, across a permeable membrane. The peritoneum is a permeable membrane. (Choice A). Diffusion is an essential principle upon which peritoneal dialysis functions. Distribution is the passive movement of solutes across a membrane. Solutes diffuse from an area of higher concentration to an area of lower concentration, across the peritoneum, until there is an equal amount of each on both sides of the membrane (Choice B). Peritoneal dialysis also allows for ultrafiltration, or the removal of excess fluid from the body. This occurs as the dialysis fluid dwells in the peritoneal cavity, causing a shift of fluid from the bloodstream into the peritoneal cavity.(Choice E)
✓ Peritoneal dialysis is a form of dialysis used to remove excess waste and fluid from the body when the kidneys can no longer perform this function. It involves placing a soft, flexible tube called a catheter into the peritoneal cavity, which is the space surrounding the abdominal organs.
✓ Peritoneal dialysis also allows for ultrafiltration, or the removal of excess fluid from the body. This occurs as the dialysis fluid dwells in the peritoneal cavity, causing a shift of fluid from the bloodstream into the peritoneal cavity.
✓ Unlike hemodialysis, which requires a patient to visit a dialysis center several times a week, peritoneal dialysis can be done at home, providing more flexibility and convenience for patients. It can also be a good option for patients with limited vascular access or who cannot tolerate hemodialysis.
