Fluid & Electrolyte imbalances

What are 5 of the most vital electrolytes that are measured with a CMP?

Sodium

Potassium

Calcium

Chloride

Magnesium

Elevated ammonia levels are defined as:

Encephalopathy

What is the effect of Vasopressin on blood vessels and the kidneys? How does this affect arterial pressure?

Blood vessels: Vasoconstriction

Kidneys: Fluid reabsorption

Increases arterial pressure

What is the primary function of ADH?

Water conservation

By what means does vasopressin increase arterial pressure?

Vasoconstriction (Inc vascular resistance)

Fluid reabsorption (Inc blood volume)

What is the makeup and tonicity of D5W solution?

5g dextrose/L of water

Goes from Isotonic to hypotonic by metabolization

What is the makeup and tonicity of D5.45 solution?

5% dextrose in 0.45% NaCl

Goes from hypertonic to hypotonic by metabolization

A patient who needs both hydration and a modest source of calories might require infusion of what type of solution?

D5W

Normal serum sodium levels

135-145 mEq/L

A sodium level below 120 mEq/L is considered

Severe hyponatremia

How can high blood glucose cause hyponatremia?

Blood glucose above the renal threshold of 180 mg/dL results in osmotic diuresis; kidneys excrete more sodium than water

Causes of hyponatremia typically include

Diuretics

Wound drainage (Especially GI)

Hyperglycemia

List some neurological, neuromuscular, intestinal, and cardiovascular manifestations of hyponatremia

Neuro: Irritable, disoriented, confused

Neuromusc: Muscle weakness, spasms

Intestinal: Abdominal cramping, diarrhea

CV changes: Bradycardia, thready/weak pulse

What medication can be administered in the event of hyponatremia to reduce diuretic effects?

Tolvaptan (Samsca); Vasopressin ADH antagonist

What type of solution should be administered in the event of severe hyponatremia?

Hypertonic (3% saline)

Causes of hypernatremia typically include

Renal failure

Corticosteroids

Excess Na intake

The imbalance in which too little total body water exists relative tot he amount of total body sodium is known as

Hypernatremia

List some of the neurological, neuromuscular, and CV manifestations of hypernatremia?

Neuro: Lethargy, drowsiness

Neuromusc: Muscle twitches, spasms

CV: Altered BP, possible cardiac arrhytmias

Nursing interventions for hypernatremia

NS infusion for dilution of Na

Diuretics (Lasix or Bumex)

Hemodialysis

What are the primary functions of potassium in the body?

Regulates heart contraction

Nerve impulse conduction

Muscle contraction

Controls intracellular osmolality

Diuretics, vomiting/diarrhea, wound drainage (Esp. GI), copious NG suction/output, or excessive diaphoresis are potential causes of what electrolyte imbalance?

Hypokalemia (<3.5 mEq/L)

List the main respiratory, cardiac, neurological and intestinal manifestations of hypokalemia

Resp: Shallow respirations

CV: Weak/thready pulse, arrhytmia

Neuro: Irritability, anxiety

Intestinal: Decreased peristalsis

Your patient is taking Lasix for hypertension, and their latest labs revealed a potassium level of 2.8 mEq/L. Does the patient's medication regimen need to be continued, changed, or stopped? Why?

Hypokalemia; Physician can switch the order to a potassium-sparing diuretic, such as Spironolactone (Aldactone)

Spinach, soybeans, halibut, bananas, cantaloupe, and papaya are excellent sources of what essential electrolyte?

Potassium

Over-supplementation, whole blood or packed RBC transfusion, renal failure, and dehydration are all potential causes of what electrolyte imbalance?

Hyperkalemia (>5 mEq/L)

How do blood transfusions or dehydration contribute as causes of hyperkalemia?

Cause hemoconcentration and decreased blood flow to the kidney; potassium is not effectively excreted in the urine.

List some CV, neuromuscular, and intestinal changes associated with hyperkalemia

CV: Bradycardia, prolonged PR interval, heart block

Neuromusc: Muscle weakness, paresthesia

Intestinal: GI motility increase/diarrhea

Nursing interventions for hyperkalemia include

Replace or d/c potassium-sparing diuretics

Exchange resins (Kayexalate)

Hemodialysis

50% Dextrose & Regular insulin

Cardiac monitoring

What is the mechanisms of exchange resins such as kayexalate?

Medication which decreases K+ by exchanging sodium for potassium in the gut

The normal range for calcium in the body is

8.5-10.5 mg/dL

Causes of hypocalcemia

MOST COMMON: Low serum albumin (Common in cirrhosis)

Poor calcium absorption (i.e. women in menopause)

Severe burns/infection

Twitching, tremors, anxiety/confusion, decreased CO, arrhythmias, and decreased myocardial contractility are manifestations of what electrolyte imbalance?

Hypocalcemia

How is hyperparathyroidism linked to hypercalcemia?

Excessive PTH pulls calcium from bones into the bloodstream, resulting in increased absorption of calcium by the kidneys and intestines.

What are 3 common causes of hypercalcemia?

Hyperparathyroidism

Thiazide diuretics

Cancer

List CV, neuromuscular, neurological, and intestinal manifestations of hypercalcemia

CV: Tachycardia, hypertension

Neuromusc: Muscle weakness, decrease in deep tendon reflexes

Neurol: Confusion, lethargy

Intestinal: Decreased gastric motility, increased abdominal girth

What are appropriate nursing interventions for treatment of hypercaclemia?

Rehydration (to increase Ca excretion)

NS infusion (inhibits reabsorption of calcium)

Loop diuretics (Lasix)

Hemodialysis