Patholophysiology Chp 8 Fluid and Electrolyte Imbalances
When examining laboratory results, the nurse notices that a patient's serum albumin level is low. The nurse recognizes the significance of decreased albumin because it can result in a decrease in which mechanism of fluid balance? pressure Osmolarity Colloid osmotic pressure Capillary permeability
Colloid osmotic pressure Colloid osmotic pressure decreases as a result of a decrease in plasma proteins, specifically albumin. This leads to an accumulation of fluid in interstitial spaces, which is edema. Increased capillary hydrostatic pressure is an increase in pressure within the capillaries and is another cause of edema. Increased capillary permeability leads to an accumulation of protein and fluids, resulting in localized edema. Osmolarity is the concentration of solutes in a kilogram of fluid.
The nurse is discussing the osmolarity of an intravenous fluid with a colleague. Which description of osmolarity by the nurse is accurate? Amount of edema in extremities Urine output in a 24-hour period Concentration of solutes in body fluids Volume of circulating fluids
Concentration of solutes in body fluids Osmolarity is the combined solute concentration in water. Osmolarity is determined by the total solute concentration within a fluid compartment and is measured as parts of solute per kilogram of water. Volume of circulating fluid is the fluid volume, not the osmolarity. Amount of edema in extremities refers to the retention of fluid in the interstitial spaces, and is measured through depth of swelling. Urine output in a 24-hour period is a determinant of fluid balance but is not the osmolarity.
Which electrolyte imbalance is most likely to result in potentially lethal arrhythmias? Hypernatremia Hyperkalemia Hypokalemia Hyponatremia
Hyperkalemia Potassium is the primary electrolyte involved in cardiac function. An elevated level of potassium can result in loss of resting potential of cardiac cells and arrhythmias. This is seen on an ECG as a high, peaked T wave, or S-T segment changes. Hypokalemia can be cardiotoxic as well, but is not usually associated with the lethal arrhythmias. Hypernatremia can lead to hypertension and central nervous system symptoms. Hyponatremia often occurs as a result of fluid and electrolyte loss—symptoms are most often nervous-system related.
A patient has been diagnosed with mild hyponatremia and asks the nurse how this can be prevented from reoccurring. Which is the nurse's correct response? "Increase fluid intake." "Add salt to food when cooking." "Increase citric acid intake." "Increase dairy intake."
"Add salt to food when cooking." Adding table salt to cooking and to prepared food will help manage mild hyponatremia. This should be done cautiously, especially in older adult patients who may have a risk for fluid volume excess. Increasing fluid intake may result in a further decrease in sodium. Increasing citric acid intake may have some health benefits, such as increased potassium, but is not associated with increased sodium. Increasing dairy intake may increase potassium but has minimal benefit to those with hyponatremia.
Due to medication, a patient is at risk for hyperkalemia. Which dietary recommendation should the nurse make to reduce this risk? "Increase dairy consumption. "Limit bananas, citrus, and milk." "Restrict fluids to 1 liter per day." "Add table salt to food."
"Limit bananas, citrus, and milk." Limiting foods that are high in potassium can help minimize the risk of developing hyperkalemia. Foods such as bananas, citrus fruits, milk, and whole grains contain potassium, and should be avoided by those with a tendency to develop hyperkalemia. Increasing dairy consumption will likely increase potassium. Adding table salt will increase sodium, but not potassium, and restricting fluids is generally appropriate for those who develop fluid volume excess and heart failure.
A patient with hypocalcemia has been placed on vitamin D and intravenous calcium salts. The patient asks, "Why am I taking vitamin D?" Which response by the nurse is accurate? "Vitamin D enhances absorption of calcium in the GI tract." "Vitamin D directly decreases calcium levels." "Low calcium levels result in vitamin D deficiency." "Decreased vitamin D levels result in increased calcium levels."
"Vitamin D enhances absorption of calcium in the GI tract." Vitamin D enhances calcium absorption in the GI tract. Dietary supplementation with vitamin D may be necessary in hypocalcemia. Vitamin D does not have an inverse effect on calcium but rather works to optimize calcium in the body.
Which clinical manifestations are indications of hyperphosphatemia? Tingling, spasms, muscle tetany, convulsions Nausea, vomiting, diarrhea Arrhythmias, chest pain, shortness of breath Confusion, fatigue, seizures
Tingling, spasms, muscle tetany, convulsions The clinical manifestations of hyperphosphatemia are the same as the signs and symptoms of hypocalcemia, since the two are inversely related. An elevated phosphate level accompanies or contributes to a decrease in calcium levels. The manifestations of low calcium include muscle spasm, tetany, and convulsions. Confusion and lethargy are more likely associated with low sodium levels. Arrhythmias and shortness of breath are more often associated with alterations in potassium levels. Nausea, vomiting, and diarrhea are more likely to be contributing factors for electrolyte imbalances.
A patient consumes canned vegetables rather than fresh vegetables on a routine basis and complains of being very thirsty. Which serum sodium level would be consistent with this behavior? 122 mEq/L 152 mEq/L 135 mEq/L 112 mEq/L
152 mEq/L A serum sodium level higher than 145 mEq/L indicates hypernatremia. This can occur as a result of the ingestion of high amounts of salt. One of the earliest manifestations is thirst, because intracellular fluid is drawn into extracellular spaces, resulting in shrinkage of cells and dry skin and membranes.
A patient with a chloride level of 70 mEq/L is presenting with confusion, sweating, and shallow respirations. Which cause should the nurse suspect for the patient's clinical manifestations? Increased fluid volume Inadequate intake of calcium A loss of gastrointestinal secretions Constipation
A loss of gastrointestinal secretions Hypochloremia is a condition of a chloride level that is less than 97 mEq/L. Loss of gastrointestinal secretions from vomiting, diarrhea, or nasogastric suction is the primary cause of hypochloremia. This volume depletion causes a loss of chloride ions. In response, the kidneys will attempt to retain more sodium in response to the volume depletion causing fluid volume to increase. It is important to remember that administration of diuretics may result in hypochloremia. Constipation or increased fluid volume is not usually associated with hypochloremia. Inadequate intake of calcium is not associated with hypochloremia.
The nurse has assessed the swelling in the lower extremities of a patient over the past few days as edema. Which statement describes the etiology of edema? Localized inflammation in extremities Increase in plasma volume Expansion of intracellular fluid Accumulation of interstitial fluid
Accumulation of interstitial fluid Edema is caused by an increase in interstitial fluid, which is the result of increased capillary pressure, membrane permeability, decreased colloid osmotic pressure, or lymphatic obstruction. There can also be an increase in sodium with accompanying water retention in the body resulting in excess interstitial fluid. Expansion of intracellular fluid can cause cells to burst and tissue destruction but does not cause edema. Increased overall plasma volume is not a direct cause of edema. Edema is not the result of localized inflammation. .
The nurse is caring for a patient who is being treated for severe hyponatremia. Which action should the nurse implement? Limit use of salt on foods Encourage patient to drink extra fluid each day Discourage use of sodium bicarbonate products Monitor patient's weight
Monitor patient's weight For severe hyponatremia, the healthcare provider may elect to utilize hypertonic fluids (2-23% sodium chloride), which will rapidly replenish the serum sodium. However, this course of treatment raises many safety concerns, owing to the risk of causing hypernatremia. To prevent overcorrection, constant monitoring is required in using hypertonic fluids. For this reason, the nurse should monitor the patient's weight carefully to assess the patient's fluid volume status. Mild hyponatremia may be treated with dietary sodium, pharmacological sodium bicarbonate, or fluid restriction. Moderate hyponatremia may be treated with lactated Ringer's solution. The use of sodium bicarbonate or limiting fluids to 1-2 liters/day are treatment solutions for mild hyponatremia. The use of hypertonic (2-23% sodium chloride) fluids is utilized when treating patients with severe hyponatremia.
A patient with diabetes has neglected to take her insulin. She presents with a blood sugar greater than 600 mg/dL and lethargy. Which electrolyte should the nurse suspect to also be elevated? Chloride Sodium Calcium Potassium
Potassium Potassium is a positively charged ion and is the primary intracellular ion. When glucose levels elevate, positively charged glucose will push potassium out of the intracellular spaces into the circulating fluid. Therefore, most patients with a very elevated blood glucose will also likely have an elevated potassium level. Sodium is an extracellular ion; calcium and chloride are not as affected by increased glucose.
Which is the most prevalent intracellular ion? Sodium Calcium Chloride Potassium
Potassium Potassium is the primary intracellular fluid ion. It is important because it determines the osmolality of intracellular fluid and facilitates a cell's resting potential. Sodium is the primary extracellular fluid ion. Calcium facilitates the exchange of sodium and potassium when a cell is polarized. Chloride ions are not a primary intra- or extracellular ion.
The nurse should recognize that which process regulates the excretion of water from the kidneys? Increased sodium levels Increase in aldosterone Release of antidiuretic hormone (ADH) Release of angiotensin
Release of antidiuretic hormone (ADH) Antidiuretic hormone (ADH) is released from the posterior pituitary in response to the circulating volume of water. This regulates the excretion of water from the body. Increased sodium levels may trigger thirst in response, but this is due to the action of ADH. Angiotensin I and Angiotensin 2 are secreted in response to decreased blood pressure, which may be caused by decreased fluid volume or other factors. Aldosterone increases sodium absorption, which increases fluid volume, but this is not the primary regulator of water excretion.
The nurse caring for a patient at risk for isotonic fluid volume excess should monitor the patient for which clinical manifestation? A decrease in energy level Excessive thirst Sudden weight gain Muscle spasms and tension
Sudden weight gain Isotonic fluid volume excess has an early symptom of weight gain of 3 to 5 lbs over one to two days due to fluid volume overload. A decrease in energy may be associated, but may be the result of other electrolyte imbalances. Excessive thirst is more likely associated with fluid volume deficit or increased glucose levels, and muscle spasms and tension are more likely associated with calcium alterations.
A patient who is at risk for developing osteoporosis asks which foods she should consume to increase calcium. Which recommendation should the nurse make? "Increase dairy products and green, leafy vegetables." "Increase fluid intake." "Any foods that are low in vitamin D." "Increase intake of citrus fruits."
Increase dairy products and green, leafy vegetables Dairy products, as well as green, leafy vegetables, are high in calcium, along with salmon, sardines, and oysters. Increasing intake of citrus fruit may have other health benefits, and may increase potassium, but will not affect calcium. Increasing fluid intake may have health benefits, but not directly related to calcium levels. Calcium and phosphate have an inverse relationship, so increasing calcium will decrease phosphate, and increasing phosphate will decrease calcium. Foods high in vitamin D are recommended because vitamin D enhances the absorption of calcium from the gastrointestinal tract.
A teenager has eaten a bag of very salty potato chips and reports being very thirsty. Which physiological response will occur? Sodium levels in extracellular fluid decrease Suppression of secretion of antidiuretic hormone (ADH) Extracellular fluid volume decreases Increased secretion of antidiuretic hormone (ADH)
Increased secretion of antidiuretic hormone (ADH) Antidiuretic hormone (ADH) secretion increases in an attempt to retain fluid to dilute the sodium in the body. As a result, urine output decreases and thirst promotes further consumption of water. As a result, extracellular fluid volume increases, and sodium levels in extracellular fluid increase. Thirst and water consumption will promote the return of fluid to intracellular spaces.
An increased production of antidiuretic hormone (ADH) will most likely result in which clinical manifestation? Third spacing Increased serum osmolality Increased urine output Decreased urine output
Increased urine output Antidiuretic hormone (ADH) is the hormone responsible for regulation of fluid excretion from the kidneys. An increased level of this hormone will likely result in large amounts of dilute urine being produced, with an increase in urinary output. Increased serum osmolality is the result of decreased fluids. This can occur as a result of increased urine output, but not as a direct result of increased ADH. Third spacing is an accumulation of fluid in an area of the body that does not normally contain fluid.
A patient is exhibiting clinical manifestations of third spacing. The nurse recognizes that this condition is caused by an accumulation of fluid in which area? Interstitial space Intracellular Extracellular Plasma
Interstitial space Third spacing involves the accumulation of fluid in areas (typically the intestinal space) that normally have no fluid or a minimal amount of fluid. Fluid lost from the intravascular space into the nonfunctional spaces can occur through several mechanisms, such as the loss of colloid osmotic pressure. This loss of the colloid osmotic pressure stems from deficits caused by either decreased intake or malproduction of proteins such as albumin. The loss of the concentration of protein in the intravascular fluid results in the loss of the water-pulling forces of colloid osmotic pressure.
Which fluid makes up the largest proportion of body weight? Plasma Intracellular fluid Extracellular fluid Interstitial fluid
Intracellular fluid Fluids make up 60% of the overall body weight. Of this, intracellular fluid makes up 40% of the weight of the body. Extracellular fluid, interstitial fluid, and plasma combine to make up an additional body weight. Fluids make up 60% of the body weight. Organs and tissue make up 40%. The fluid in the body, by weight, is as follows: 40% intracellular fluid 20% extracellular fluid 15% interstitial fluid 5% plasma
A patient presents with a serum sodium level of 159 mEq/L and reports increased thirst. The nurse understands which mechanism is causing the patient's thirst? Decreased blood pressure Extracellular fluid dehydration Increased glucose levels Intracellular fluid dehydration
Intracellular fluid dehydration Intracellular fluid dehydration causes cells to shrink and become dry, which is the mechanism that causes thirst. When sodium is elevated (hypernatremia), fluid is drawn into the extracellular spaces. Blood pressure may decrease with hypernatremia, especially in fluid volume deficit, but this is not the mechanism that causes thirst. Increased glucose levels can result in extreme thirst, but this is not associated with hypernatremia
A patient is admitted to an intensive care unit with severe burns over 75% of his body. He is receiving intravenous (IV) hydration for fluid volume deficit. His serum sodium is normal, hematocrit is elevated, and urine output is decreased. Which type of fluid volume deficit is the patient most likely experiencing? Hypotonic Hyperkalemic Hyponatremic Isotonic
Isotonic Isotonic fluid volume deficit occurs when fluid and electrolytes are lost from intracellular space in a symmetrical fashion—fluids and electrolytes are lost together. The serum sodium levels are normal and the hematocrit increases because cells shrink and blood becomes more concentrated. Hyponatremic fluid volume deficit results in a loss of sodium. Hyperkalemic refers to elevated potassium level. Hypotonic refers to a lower serum osmolality than body fluids.
Which is one of the most common cause of hyponatremia? Hypertension Intracellular dehydration Hypoglycemia Loss of body fluids
Loss of body fluids Hyponatremia is usually associated with fluid volume loss that can occur with diarrhea, vomiting, or other gastrointestinal-associated mechanisms. When fluid loss occurs, sodium is excreted as well. Intracellular dehydration is most commonly associated with hypernatremia, which results in shrinkage of cells and thirst. Hypoglycemia is not associated with decreased sodium levels. Hypertension is more likely to occur in hypernatremia, because fluid may be retained to dilute the sodium levels.
Which is the primary trigger of the renin-angiotensin-aldosterone system (RAAS)? Low blood pressure Increased pressure in the renal tubules Decreased serum osmolality Increase in serum sodium
Low blood pressure Low blood pressure is the trigger for the renin-angiotensin-aldosterone system (RAAS). In response to hypovolemia, serum sodium is increased, which in turn causes fluid retention resulting in an increase in circulating fluid volume and blood pressure. An increase in serum sodium will result in an increase in blood pressure, which does not trigger the renin-angiotensin-aldosterone system (RAAS). Decreased serum osmolality does not have an effect on the renin-angiotensin-aldosterone system (RAAS). Increased pressure in renal tubules usually occurs as a result of increased blood pressure, which does not trigger the renin-angiotensin-aldosterone system (RAAS).
A patient presents in the emergency department bleeding profusely from several stab wounds. His blood pressure is critically low at 56/30 mmHg and his serum sodium level is 112 mEq/L. How will the kidneys respond? The low sodium will likely stimulate an increase in potassium, which could cause cardiac arrhythmias. Kidney function will slow down to allow fluid to build up, increasing the blood pressure. Kidneys will begin to excrete urine in large amounts. The low blood pressure will stimulate the renin-angiotensin-aldosterone system (RAAS) to retain sodium and fluid.
The low blood pressure will stimulate the renin-angiotensin-aldosterone system (RAAS) to retain sodium and fluid. The low blood pressure is the stimulus for the renin-angiotensin-aldosterone system (RAAS), resulting in sodium and fluid retention that leads to an increase in blood pressure. The kidneys will not increase filtration or secretion, and kidney function will not be immediately affected—this is a later stage manifestation. Potassium may decrease, but this is not a function of the kidneys. Cardiac arrhythmias may result from decreased oxygenation and perfusion to cardiac tissue.
The nurse notices that a patient is having increased swelling in the abdomen and edema in all extremities. The patient reports shortness of breath and constipation. How should the nurse describe this patient's condition? Lymphatic obstruction Third spacing Increased osmolality Decreased antidiuretic hormone (ADH)
Third spacing Third spacing is a type of edema in which fluid is retained in areas of the body that do not normally have fluid, typically the intestinal space. The fluid in this space is nonfunctional and can compress vascular areas, inhibiting circulation and perfusion. Increased osmolality refers to the concentration of solutes in a kilogram of solution of fluids. Decreased antidiuretic hormone (ADH) is a decrease in the production of a hormone that regulations excretion of water. A lymphatic obstruction blocks circulation of fluids in a certain area, causing edema.
The nurse is caring for a patient with dehydration. The nurse should expect the patient to have which clinical manifestations? Fever, nausea, vomiting Thirst, headache, dizziness, confusion Light-colored urine, hunger, muscle cramping Chest pain, edema, lethargy
Thirst, headache, dizziness, confusion Dehydration occurs when there is a deficit in the circulating fluid volume. Symptoms of dehydration include headache, thirst, poor skin turgor, decreased urine output, dry skin, and dry mucous membranes.
Which condition places a pediatric patient at highest risk for developing hypokalemia? Muscle soreness Vomiting and diarrhea Headache and fatigue Weakness and confusion
Vomiting and diarrhea The highest risk for hypokalemia in pediatric patients is the result of fluid loss due to vomiting and diarrhea. Weakness and confusion are likely associated with low levels of calcium. Headache and fatigue are likely associated with low sodium, as is muscle soreness.
A patient has a sodium level of 150 mEq/L, indicating hypernatremia. Which clinical manifestation should the nurse expect to observe in this patient? Weight gain Poor skin turgor Weight loss Dry mucous membranes
Weight gain An increase in extracellular sodium levels leads to fluid volume overload. The elevated sodium levels lead to an excess of fluid retention to attempt to neutralize the sodium excess. The fluid volume excess leads to edema and weight gain. Poor skin turgor and dry mucous membranes are more likely a result of fluid volume deficit that accompanies dehydration.
A patient has lost a large amount of blood and fluid due to surgery and states he is thirsty. The nurse should recognize which process is a cause for his thirst? Inability to drink prior to surgery Loss of potassium Slow functioning of kidneys Fluids moving from inside the cells into the ECF
Fluids moving from inside the cells into the ECF Thirst is an early manifestation of decreased fluid volume. This occurs because intracellular fluid is pulled into extracellular spaces in order to dilute the amount of sodium. Urine output is decreased, and hypotension and tachycardia may occur.
A pediatric patient with isotonic fluid deficit is being treated aggressively with both fluid volume and electrolytes. For which reason should the nurse recognize that this type of fluid volume deficit is potentially more dangerous in children? Children retain fluids more easily than adults. Children are more likely to suffer more severe injuries. Children are less compliant with treatment. Fluid is a higher percentage of total body weight in children.
Fluid is a higher percentage of total body weight in children. A higher percentage of total body weight in children is fluid, so isotonic fluid loss is potentially far more dangerous in children. For this reason, children should be monitored closely for manifestations of fluid loss. Compliance with treatment is not associated with severity of isotonic fluid volume deficit. Children do not retain fluids more effectively than adults. There is no greater likelihood that children will experience greater injuries than adults. When caring for pediatric patients with isotonic fluid volume deficit: Electrolytes should be corrected along with fluids. Hemodynamic monitoring should be done while correcting a fluid deficit. The amount of fluid and electrolyte replacement is dependent on the degree of fluid deficit.
A patient has been prescribed a 0.45% saline intravenous solution for isotonic fluid volume deficit. Which type of solution will the patient receive? Plasma Hypotonic Isotonic Hypertonic
Hypotonic Hypotonic solutions have a lower osmolality than body fluids. An example of a hypotonic solution is 0.45% sodium chloride. Isotonic solutions have the same osmolality as body fluids. Normal saline (0.9% sodium chloride) is an isotonic solution. Hypotonic solutions have a lower osmolality than body fluids. An example of a hypotonic solution is 0.45% sodium chloride. An equivalent osmolality is one in which solute concentrations in fluid match those in cells. A higher or lower sodium or fluid concentration results in alterations.