Term
| Amount of water (% body weight) |
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Definition
| 70-80% in infants; 50-60% in adults; 45-55% in older adults |
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Term
| Prevalent cation in the ICF |
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Definition
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Term
| Prevalent anion in the ICF |
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Definition
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Term
| Prevalent cation in the ECF |
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Definition
|
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Term
| Prevalent anion in the ECF |
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Definition
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Term
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Definition
| Amount of pressure required to stop osmotic flow of water; Determined by the concentration of solutes in the solution. |
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Term
|
Definition
| Force within the fluid compartment; force that pushes water out of the vascular system. |
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Term
|
Definition
| Osmotic pressure exerted by colloids in solution (such as protein). |
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Term
| Causes of plasma-to-interstitial fluid shift. |
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Definition
(1) Elevation of hydrostatic pressure.
(2) Decrease in plasma oncotic pressure.
(3) Elevation of interstitial oncotic pressure. |
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Term
| Causes of interstitial-to-plasma fluid shift. |
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Definition
| Increased plasma osmotic or oncotic pressure. |
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Term
|
Definition
| Normal distribution of fluid in ICF and ECF |
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Term
|
Definition
| Abnormal accumulation of interstitial fluid (edema). |
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Term
|
Definition
| Fluid accumulation in part of body where it is not easily exchanged with ECF. |
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Term
| Hypothalamic regulation of water balance. |
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Definition
| Osmoreceptors in hypothalamus sense fluid deficit; stimulate thirst and ADH release; result in increased free water and decreased plasma osmolarity. |
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Term
| Pituitary regulation of water balance. |
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Definition
| Posterior pituitary releases ADH; also induced by stress nausea, nicotine, and morphine. |
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Term
| Adrenal cortical regulation of water balance. |
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Definition
| Releases glucocorticoids (cortisol) and mineralocorticoids (aldosterone) when stimulated by ACTH or Ang II, respectively. |
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Term
| Renal regulation of fluid balance. |
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Definition
| Selective reabsorption of water/electrolytes; site of ADH and aldosterone action. |
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Term
| Cardiac regulation of fluid balance. |
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Definition
| Natriuretic peptides (ANP) produced by cardiomyocytes in response to increased atrial pressure. ANP antagonizes the RAAS pathway by suppressing secretion of aldosterone, renin, and ADH. |
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Term
| GI regulation of fluid balance. |
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Definition
| Elimination of small amounts of water by GI tract; diarrhea and vomiting can lead to significant losses. |
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Term
|
Definition
| Invisible vaporization from lungs and skin; about 600-900mL/day. |
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Term
| Gerontological considerations for fluid balance. |
|
Definition
(1) Decreased ability to conserve water by kidneys.
(2) Decreased ADH and ANP.
(3) Loss of subcutaneous tissue and moisture.
(4) Reduced thirst mechanisms. |
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Term
| S/S of fluid volume excess |
|
Definition
(1) headache, confusion, lethargy
(2) peripheral edema, JVD, bounding pulse, inc BP
(3) dyspnea, crackles, pulmonary edema
(4) polyuria
(5) seizures, coma |
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|
Term
| Causes of fluid retention leading to fluid volume excess |
|
Definition
| heart failure, renal failure, SIADH, Cushings, etc. |
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Term
| Treatment for fluid volume excess |
|
Definition
(1) diuretics
(2) fluid restriction
(3) sodium restriction
(4) paracentisis (extreme) |
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|
Term
| Causes of fluid volume deficit |
|
Definition
(1) abnormal loss of body fluids (e.g. diarrhea, vomiting, hemorrhage, etc)
(2) inadequate fluid intake
(3) plasma-to-interstitial fluid shift ("3rd spacing") |
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|
Term
| S/S of fluid volume deficit |
|
Definition
(1) restless, drowsy, lethargic, confused
(2) thirst, dry mouth
(3) decreased skin turgor
(4) decreased capillary refill
(5) postural hypotension, inc pulse, dec CVP
(6) dec UOP, inc urine concentration
(7) inc respiratory rate
(8) weight loss
(9) seizure, coma |
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|
Term
| Interventions for fluid volume deficit |
|
Definition
| - replace fluids and electrolytes with isotonic IV solution (e.g. LR, NS, blood, etc.) |
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|
Term
|
Definition
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|
Term
|
Definition
(1) water deficit
(2) inc sodium intake
(3) dec sodium excretion (aldosterone mechanism) |
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|
Term
| Treatment for hypernatremia |
|
Definition
(1) prevent continued water loss by replacing fluids
(2) dilute sodium with hypotonic saline (0.45%NaCl) or D5W
(3) promote excretion of excess sodium w/diuretics |
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|
Term
|
Definition
(1) restless, agitated, twitching
(2) thirst
(3) flushed skin
(4) also may be symptoms of fluid excess or deficit |
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|
Term
|
Definition
(1) loss of sodium-containing fluids (GI, sweat, urine)
(2) water excess (sodium dilution) |
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|
Term
|
Definition
| - first manifested in the CNS; similar to those of hypernatremia |
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|
Term
| Interventions for hyponatremia |
|
Definition
(1) fluid restriction
(2) hypertonic saline solution IV (3% NaCl) |
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|
Term
| Potassium: Normal Lab Value |
|
Definition
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Term
|
Definition
(1) inc intake (e.g. potassium-containing salt substitute)
(2) impaired renal excretion of K+ (most common)
(3) shift of K+ from ICF to ECF (e.g. w/ burn or crush injury; inc tissue catabolism; also metabolic acidosis) |
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|
Term
|
Definition
(1) irritable, anxious
(2) weakness, paresthesias
(3) abdominal cramping, diarrhea
(4) irregular pulse, cardiac arrest
(5) ECG changes associated with increased excitability (Vfib, wide QRS, long PR, ST depression) |
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Term
| Interventions for hyperkalemia |
|
Definition
(1) dec intake
(2) inc elimination of K+ (kayexalate, dialysis, fluid intake)
(3) IV insulin to force ECF-->ICF movement of K+ |
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|
Term
|
Definition
(1) abnormal K+ loss (diuresis, esp via aldosterone mech)
(2) shift of K+ from ECF to ICF (e.g. in metabolic acidosis or new cell formation)
(3) rarely, deficient dietary intake of K+ |
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|
Term
|
Definition
(1) associate with decreased excitability of nerve/muscle cells
(2) ECG changes: increased P, flattened T, brady, enhanced digoxin toxicity, ventricular arrhythmias
(3) fatigue, weakness, leg cramps
(4) nausea, vomiting, paralytic ileus
(5) paresthesias, decreased reflexes
(6) polyuria, hyperglycemia |
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|
Term
| Interventions for hypokalemia |
|
Definition
- administer KCl supplements (if UOP is >0.5mL/kg)
- IV fluid should be less than 10-20mEq/hr to prevent cardiac arrest |
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|
Term
| Calcium: Normal Lab Value |
|
Definition
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