Major Fluid and Electrolyte Imbalances
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Imbalance
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Contributing Factors
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Signs and Symptoms / Laboratory
Findings
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Potassium deficit
(hypokalemia)
Serum potassium
< 3.5 mEq/L
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· Diarrhea, vomiting
· Gastric suction
· Corticosteroid administration
· Diuretics
· Hyperaldosteronism
· Alkalosis
· Carbenicillin, Amphotericin B
· Bulimia, starvation
· Osmotic diuresis
· Digoxin toxicity
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Fatigue,
anorexia, nausea and vomiting, muscle weakness, polyuria, decreased bowel
motility, ventricular asystole or fibrillation, parethesias, leg cramps, â BP, ileus, abdominal distention, hypoactive reflexes
ECG:
Flattened
T waves, prominent U waves, ST depression, prolonged PR interval
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Potassium
excess
(hyperkalemia)
Serum
potassium
> 5.0 mEq/L
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· Pseudohyperkalemia
· Oliguric renal failure
· Use of potassium-conserving
diuretics in pts. with renal insufficiency
· Metabolic acidosis
· Addison’s dse
· Crush injury
· Burns
· Stored bank blood transfusions
· Rapid IV administration of
potassium
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Vague
muscular weakness, tachycardia à bradycardia, dysrhythmias, flaccid
paralysis, paresthesias, intestinal colic, cramps, irritability, anxiety
ECG:
Tall
tented T waves, prolonged PR interval and QRS duration, absent P waves, ST
depression
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Major Fluid and Electrolyte Imbalances
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Imbalance
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Contributing Factors
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Signs and Symptoms / Laboratory
Findings
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Calcium deficit
(hypocalcemia)
Serum calcium
< 8.5 mg/dL
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· Hypoparathyroidism (may follow
thyroid surgery or radical neck dissection)
· Malabsorption
· Pancreatitis
· Alkalosis
· Vitamin D deficiency
· Massive SQ infection
· Generalized peritonitis
· Massive transfusion of citrated
blood
· Chronic diarrhea
· Diuretic phase of renal failure
· Decreased PTH, á PO4
· Fistulas, Burns
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Numbness,
tingling of fingers, toes, and circumoral region; positive Trousseau’s sign
and Chvostek’s sign; seizures, carpopedal spasms, hyperactive deep tendon
reflexes, irritability, bronchospasms, anxiety, impaired clotting time, â prothrombin
ECG:
Prolonged
QT interval and lengthened ST
Lab findings:
â Mg++
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Calcium
excess
(hypercalcemia)
Serum
calcium
> 10.5 mg/dL
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· Hyperparathyroidism
· Malignant neoplastic dse
· Prolonged immobilization
· Overuse of calcium supplements
· Vitamin D excess
· Oliguric phase of renal failure
· Acidosis
· Corticosteroid therapy
· Thiazide diuretic use
· Increased PTH
· Digoxin toxicity
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Muscular
weakness, constipation, anorexia, nausea and vomiting, polyuria, polydipsia,
dehydration, hypoactive deep tendon reflexes, lethargy, deep bone pain,
pathologic fractures, flank pain, and calcium stones
ECG:
Shortened
ST segment and QT interval, bradycardia, heart blocks
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Major Fluid and Electrolyte Imbalances
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Imbalance
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Contributing Factors
|
Signs and Symptoms / Laboratory
Findings
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Magnesium deficit
(hypomagnesemia)
Serum magnesium
< 1.8 mg/dL
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· Chronic alcoholism
· Hyperparathyroidism
· Hyperaldosteronism
· Diuretic phase of renal failure
· Malabsorptive disorders
· Diabetic ketoacidosis
· Refeeding after starvation
· Parenteral nutrition
· Chronic laxative use
· Diarrhea
· Acute MI, heart failure
· Decreased serum K+ and Ca++
· Certain pharmacologic agents
(gentamicin, cisplatin, cyclosporine)
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Neuromuscular
irritability, positive Trousseau’s and Chvostek’s signs, insomnia, mood
changes, anorexia, vomiting, increased tendon reflexes, á BP
ECG:
PVCs, flat
or inverted T waves, depressed ST segment, prolonged PR interval and widened
QRS
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Magnesium
excess
(hypermagnesemia)
Serum
magnesium
> 2.7 mg/dL
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· Oliguric phase of renal failure
(particularly when magnesium-containing medications are administered)
· Adrenal insufficiency
· Excessive IV magnesium
administration
· DKA
· hypothyroidism
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Flushing,
hypotension, drowsiness, hypoactive reflexes, depressed respirations, cardiac
arrest and coma, diaphoresis
ECG:
Tachycardia
à bradycardia,
prolonged PR interval and QRS
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Major Fluid and Electrolyte Imbalances
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Imbalance
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Contributing Factors
|
Signs and Symptoms / Laboratory
Findings
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Chlorine deficit
(hypochloremia)
Serum chloride < 96 mEq/L
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· Addison’s disease
· Reduced chloride intake or
absorption
· Untreated diabetic ketoacidosis
· Chronic respiratory acidosis
· Excessive sweating
· Vomiting, diarrhea
· Gastric suction
· Sodium and potassium deficiency
· Metabolic alkalosis
· Loop, osmotic, or thiazide diuretic
use
· Overuse of bicarbonate
· Rapid removal of ascitic fluid w/
high Na content
· IVF that lack chloride (dextrose
and water)
· Draining fistulas and ileostomies
· Heart failure
· Cystic fibrosis
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Agitation,
irritability, tremors, muscle cramps, hyperactive deep tendon reflexes,
hypertonicity, tetany, slow shallow respirations, seizures, dysrhytmias, coma
Lab findings:
â serum chloride, â serum sodium, á pH,
á serum bicarbonate, á total carbon dioxide content, â urine chloride level, â serum potassium
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Chloride
excess
(hyperchloremia)
Serum
chloride
> 108 mEq/L
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· Excessive sodium chloride infusions
with water loss
· Head injury (sodium retention)
· Hypernatremia
· Renal failure
· Corticosteroid use
· Dehydration
· Sever diarrhea (loss of
bicarbonate)
· Respiratory and metabolic alkalosis
· Administration of diuretics
· Overdose of salicylates (Kayexalate, Acetazolamide, phenylbutazone
and ammonium chloride)
· Hyperparathyroidism
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Tachypnea,
lethargy, weakness, deep rapid respirations, decline in cognitive status,
decreased CO, dyspnea, tachycardia, pitting edema, dysrhythmias, coma
Labs indicate:
á serum chloride, á serum potassium and sodium, â serum pH, â serum bicarbonate,
á urinary chloride level
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