Fluids and Electrolytes

total body water accounts for __% or more of body weight

water is contained primarily in

interstitial water accounts for __% of extracellular water

intravascular water or plasma water, constitutes __% of extracellular water volume or 4-7% of body weight

in the intracellular compartment __ is the dominant cation

in the interstitial and intravascular compartments __ is the dominant cation

electrical neutrality is maintained by a balanced amount of

to maintain electrical neutrality, the negative charge on plasma albumin requires an increase in

the redistribution of ions across the semipermeable membrane is called the

refers to the number of particles dissolved in a solution

is calculated by considering only the concentration of impermeable solutes in solution

___ is an enzyme released by the juxtaglomerular cells of the afferent arteriole in response to a decrease in arterial blood pressure, hypovolemia, hyponatremia, and increased beta-adrenergic activity

Renin converts angiotensinogen to angiotensin I which is then converted to angiotensin II in the pulmonary circulation by

Angiotensin releases ___ from the renal cortex

Aldosterone acts on the distal tubules and collecting ducts to

angiotensin increases

normally and adult ingests __L of water per day

___ mL/day is the minimal volume required to allow solute excretion

chronic volume depletion is manifested by

Acute volume losses are manifested by

normal dietary salt intake is __g/day

hypernatremia is defined as a serum sodium concentration that exceeds __ mEq/L

hypernatremia is always accompanied by

any net gain in sodium will increase the

hypernatremia may be due to

ordinarily the hyperosmolar state of hypernatremia will drive thirst and

in surgical patients, hypernatremia may result from the administration of __ which lead to free water depletion

neurologic symptoms of hypernatremia

rapid sodium increases will lead to

therapy for hypernatremia is directed first at

once intravascular volume is restored in hypernatremia, it is further corrected by administration of

hyponatremia is defined as a serum sodium concentration that is less than __mEq/L

hyponatremia may be caused by

symptoms of hyponatremia are

cellular swelling in hyponatremia is induced by

in hyponatremia cerebral swelling causes

patients in this group often have edema

causes include renal failure, CHF, COPD, severe liver disease

the most common cause of normovolemic hyponatremia is

SIADH is seen in patients with

patients with hypovolemic hyponatremia have

in hypervolemic hyponatremic patients the treatment includes

patients with SIADH usually respond to

in hypovolemic hyponatremic patients treatment includes

in asymptomatic patients, hyponatremia should be treated

with symptomatic hyponatremia, current recommendations are to increase the serum sodium concentration no faster than __mEq/L/hr

in patients with stupor, coma, or other severe neurologic symptoms from hyponatremia __ is used

most of the bodies potassium is found in

the normal plasma potassium concentration is __ mEq/L

the usually dietary intake of potassium is __ mEq/kg

hyperkalemia is defined as a serum potassium concentration greater than __ mEq/L

hyperkalemia can result from

the most common cause of metabolic alkalosis in surgical patients is

the peritoneal surfaces represent __% fo body surface area

during laparotomy, the expected evaporative fluid loss from exposed peritoneum is __ mL/kg/hr

hyperphosphatemia may result from

the stress response to surgery results in the release of

hyperkalemia occurs with __ due to transcellular exchange of K+ and H+

extrarenal causes of hyperkalemia

iatrogenic causes of hyperkalemia

the earliest EKG abnormality of hyperkalemia is

as plasma potassium increases

further increases in K+ concentration are associated with

the final effect of hyperkalemia on the heart is

extracardiac symptoms of hyperkalemia

to reverse cardiac toxicity in hyperkalemia __ should be administered

in hyperkalemia the response to calcium salt therapy occurs in

in hyperkalemia concurrent treatment with __ moves K+ into cells

potassium can be removed by treatment with the cation-exchange resin

the most effective method of removing potassium is

when using ___ to treat hyperkalemia, the onset of action is slow, and the effects last 4-6 hours

hypokalemia is defined as a serum potassium concentration that is less than __mEq/L

hypokalemia is a common problem in surgical patients and is usually caused by

___ often coexists with hypokalemia

metabolic acidosis decreases

EKG may show ___ in hypokalemia

in patients taking digoxin __ can provoke life threatening arrhythmias

potassium should be given __ unless the hypokalemia is severe (<2.5 mEq/L)

the serum ionized calcium concentration is maintained within a narrow range of ___ mg/dL

a reduction in serum calcium stimulates a release of

parathyroid hormone increases

PTH enhances

PTH stimulates

hypercalcemia is defined as ionized calcium concentration that exceeds __ mg/dL

although hypercalcemia is most frequently associated with hyperparathyroidism in surgical patients, it is also commonly associated with

other causes of enhanced bone reabsorption

cardiovascular manifestations of hypercalcemia include

GI effects of hypercalcemia

the most common renal defect associated with hypercalcemia is

if hyperparathyroidism is the cause of hypercalcemia the best treatment is

initial supportive therapy for hypercalcemia includes

__ reduces bone reabsorption and has an immediate effect

___ are highly effective inhibitors of osteoclast activity but have a delayed onset of 2-3 days

hypocalcemia is defined as an ionized calcium concentration of less than __ mg/dL

hypocalcemia is seen in

neuromuscular findings in hypocalcemia include

cardiovascular symptoms of hypocalcemia include

EKG findings with hypocalcemia

in patients with symptomatic or severe hypocalcemia ___ is indicated

fixed acids

___ are the main buffers in the body

in body fluids CO2 combines with water to form

kidneys can compensate for the buffer lost during CO2 excretion by the lungs with

metabolic acidosis is present when pH is less than 7.35 and plasma bicarbonate is less than __ mEq/L

in spontaneously breathing patients the increase in hydrogen ion concentration should stimulate __ thereby decreasing PCO2

the presence or absence of an ___ helps to categorized metabolic acidoses

the anion gap is calculated as the difference between the concentrations of

the causes of anion gap acidosis can be remembered by the mnemonic

Dr. Maples stands for

in trauma patients metabolic acidosis must be assumed to be due to

non-anion gap metabolic acidosis is characterized by loss of

common causes of non-anion gap metabolic acidosis

therapy with ___ is reserved for those in severe metabolic acidosis (<7.2), and in those with life threatening ventricular arrhythmias, hemodynamic instability, inadequate compensatory response

explained by the inability of the kidney to excrete excess bicarbonate or to retain hydrogen ion

metabolic alkalosis is usually accompanied by

respiratory acidosis is present when the pH is low and the PCO2 is

respiratory acidosis is due to

treatment of respiratory acidosis may require

respiratory alkalosis is present when the pH is high and the PCO2 is

caused by alveolar hyperventilation

in the surgical patient respiratory alkalosis may be caused by

in acute respiratory alkalosis renal compensation is

in chronic respiratory alkalosis renal compensation is by

most patients with respiratory alkalosis are

hyperventilation is particularly dangerous in patients with subarachnoid hemorrhage because it exacerbates

Water constitutes __% of total body weight in humans

Total body water is inversely proportional to the amount of __

__ are the major cations of the intracellular space

__ are the major anions of the intracellular space

__ are the major anions of the extracellular space

__ is the major cation of the extracellular space

__ determines the movement of fluid across the cell membrane

Except for transient changes, the intracellular and extracellular fluid compartments are in __

The transfer of fluid between the vascular and interstitial compartments occurs across the capillary wall and is governed by the balance between ___

Hemodynamic alterations to a perceived volume reduction

__ promotes salt and water retention in the kidneys

__ is released from the atrial myocytes in response to atrial stretch associated with volume expansion

__ increases GFR and inhibits sodium reabsorption in the collecting ducts

__% of total body blood is in the atrial compartment

True volume depletion

When volume depletion occurs from renal losses the urine is inappropriately __

Mild volume depletion may be associated with __

Patients with severe volume depletion may exhibit __

vasoconstrictor hormones released in response to hypovolemia

if doubt exists about the state of hydration, measurement of the pulmonary __ permits assessment of the intravascular volume status

nearly all of the volume of solution containing __ are retained in the extrarenal space

__ are the preferred parenteral solutions for the treatment of hypovolemia

only 1/3 of infused __ remains in the extracellular compartment

__ occurs when salt and water intake exceeds renal and extrarenal losses

sever hypoalbuminemia associated with liver disease, nephrotic syndrome, or severe malnutrition may lead to __

the mainstay in treating volume excess is ___

Diuretics enhance

most patients with nephrotic syndrome have increased effective circulating volume resulting from

___ inhibit sodium, chloride and potassium cotransporter of the thick ascending loop of Henle

loop diuretics __ calcium excretion

thiazide diuretics __ calcium excretion

__inhibit the sodium and chloride cotransporter of the distal tubule

__ are useful in managing hypercalcemia

__ are useful in managing calcium stone formation

potassium sparing diuretics

decreases sodium reabsorption in the cortical collecting duct

because __ is the major cation in ght ECF, disorders of osmolality are generally reflected by and abnormal __ concentration

__ causes renal water conservation by increasing water permeability and water reabsorption in the collecting ducts

baroreceptors in the venous and arterial circulation stimulate __ release through neuronal pathways when the EDF volume is reduced by about 10%

Hyperglycemia and the use of mannitol may result in __ because of a water shift from the intracellular to extracellular space

most hyponatremic disorders are associated with

failure to suppress ADH secretion in response to hypotonicity

in most instances hypernatremia is caused by __ rather than by sodium gain

__ is a powerful stimulus for thirst

patients unable to sense thirst or with a lack of available water may develop

a disorder in which the collecting tubule is impermeable to water

hypernatremia that is associated with hypovolemia implies __ in addition to the water deficit

hypernatremia that is associated with hypovolemia requires __

administration of fluids that are __ relative to the urine corrects hypernatremia

the ascending limb of the loop of Henle is __ to water

the ascending limb of the loop of Henle is __ to NaCl

the descending limb of the loop of Henle is __ to water

if the blood is hypo-osmolar then ADH will be turned __

if the blood is hyperosmolar then ADH will be turned __

if the blood is hypo-osmolar and ADH is turned on this is called __

function of ADH

__ is a powerful vasoconstrictor and increases cardiac output

__ initiates the active transport of Na from the distal tubules and collecting ducts into the bloodstream. this promotes the reabsorption of water

major stimulus for angiotensin II

major site of action of angiotensin II

major stimulation of aldosterone

major site of action of aldosterone

major stimulus for atrial natriuretic factor

major site of action for atrial natriuretic factor

__% of body water is in the ICF

__% of body water is in the ECF

__% of ECF is intravascular

__% of ECF is interstitial

effective circulating volume is the same as

hyperosmolar is the same thing as

hypo-osmolar is the same thing as

effective plasma osmolality is calculated by

normal saline is given for

D5W is given for

__ is a true vascular volume expander

if the serum is hyperosmotic the urine should be __

if the serum is hypoosmotic the urine should be __

if the kidneys are unable to to concentrate urine this is called

in SIADH if the serum osmolality is low the urine osmolality will be

in DI or low ADH if the serum osmolality is high then the urine osmolality will be

if the patient is hyponatremic, hypovolemic treat with

if the patient is hyponatremic and euvolemic treat with

if the patient is hyponatremic and hypervolemic treat with

when a patient is in DKA you give them __ until the anion gap normalizes then you give them insulin

in hyponatremia always correct sodium to __

in hyponatremia correct the sodium at __ mEq/L/hr

if you correct hyponatremia too fast you can cause

hypernatremia and hypovolemia treat with

hypernatremia and euvolemia treat with

hypernatremia and hypervolemia treat with

don't use __ when treating diabetes insipidus

major complication of rapid correction of chronic hypernatremia is __

safe initial correction of hypernatremia is at the rate of __mEq/L/hr

hypernatremia with severe hypovolemia treat with

with a patient that is hypernatremic bring the Na to