Fluid and Electrolyte Questions to Study

Isotonic Solutions:

-0.9% NS (crystalloid) -Lactated Ringers (crystalloid)

Hypotonic Solutions (<0.9% NS)

-5% Dextrose in water (crystalloid, starts as hypotonic, becomes iso) -0.45% NS (crystalloid)

A client diagnosed with hypernatremia needs fluid volume replacement. What intravenous solution would be the safest for the nurse to administer?

0.45% sodium chloride A hypotonic solution (half-strength saline) is the solution of choice and considered safer than 5% dextrose in water because it allows a gradual reduction in the serum sodium level, thereby decreasing the risk of cerebral edema. An isotonic solution (0.9%) is not desirable as a supplement because it provides Na and CL.

Hypertonic Solutions (>0.9%)

3% Saline 5% Saline 5% Dextrose in 0.45% Saline 5% Dextrose in 0.9% Saline 5% Dextrose in Lactated Ringers 10% Dextrose in water

serum calcium level

8.5-10

Hypocalcemia causes what sign

Trousseau's sign in the hands and Chvostek sign in the face

Which findings indicate that a client has developed water intoxication secondary to treatment for diabetes insipidus?

Correct response: Confusion and seizures Explanation: Classic signs of water intoxication include confusion and seizures, both of which are caused by cerebral edema. Weight gain will also occur. Sunken eyeballs, thirst, and increased BUN levels indicate fluid volume deficit. Spasticity, flaccidity, and tetany are unrelated to water intoxication.

A physician orders an isotonic I.V. solution for a client. Which solution should the nurse plan to administer?

Correct response: Lactated Ringer's solution Lactated Ringer's solution, with an osmolality of approximately 273 mOsm/L, is isotonic. The nurse shouldn't give half-normal saline solution because it's hypotonic, with an osmolality of 154 mOsm/L. Giving 5% dextrose and normal saline solution (with an osmolality of 559 mOsm/L) or 10% dextrose in water (with an osmolality of 505 mOsm/L) also would be incorrect because these solutions are hypertonic.

A client with hypervolemia asks the nurse what mechanism in the sodium potassium pump will move the excess body fluid. What is the nurse's best answer?

Correct response: active transport Explanation: Active transport is the physiologic pump that moves fluid from an area of lower concentration to one of higher concentration. Active transport requires adenosine triphosphate for energy. Passive osmosis does not require energy for transport. Free flow is transport of water naturally. Passive elimination is a filter process carried out in the kidneys.